# Welcome

## Welcome to Bituo Technik Documentation

**Empower the safe and efficient use of electricity.**

Welcome to the official documentation center for **Bituo Technik**. We are a forward-looking provider of electrical monitoring technologies, dedicated to enhancing safety and efficiency in electricity use for everyone through innovative installation products.

Here, you will find comprehensive guides, technical specifications, API references, and developer resources for all our product lines.

***

### 📚 Documentation Collections

Select a module below to start exploring our resources:

<i class="fa-book">:book:</i> [**Product Document**](/product-document/overview)**:** Access technical manuals, specifications, wiring diagrams, and ordering information for our electrical monitoring devices and electronic components & systems.

<i class="fa-signs-post">:signs-post:</i> **Application Guides:** System-level integration guides for real-world deployment scenarios - such as EV charger dynamic load balancing and solar inverter export limiting | *For: System Integrators · Software Engineers*

<i class="fa-gear-api">:gear-api:</i> [**Device API**](/device-api/spm-sdm-zigbee-cluster-reference)**:** Explore comprehensive API documentation for our supported open protocols (Zigbee, BLE, Modbus, MQTT, HTTP/REST, etc.) to enable seamless system integration. | *For: System Integrators · Platform Developers*

<i class="fa-hard-drive">:hard-drive:</i> **Hardware Integration:** Application notes and integration guides for our electronic components, including current transformers, BRCS sensors, and communication modules.| *For: Hardware Engineers*&#x20;

<i class="fa-laptop-code">:laptop-code:</i> [**Custom Firmware**](/custom-firmware/sdm01-combo-esp8685)**:** Flashing guides, pinout references, and register-level documentation for building custom firmware on our open hardware. Includes sample code and SDK references to accelerate your development. | *For: Embedded Developers · Makers & DIY Enthusiasts*

<i class="fa-question">:question:</i>[**FAQ**](/faq/overview)**:** Find quick answers to common questions covering product selection, installation, connectivity, third-party integrations, data measurement concepts, and more.

<i class="fa-bug">:bug:</i>[**Troubleshooting**](/troubleshooting/overview)**:** Get step-by-step troubleshooting guides and solutions for common issues, such as offline devices, wiring errors, abnormal data readings, and more.

<i class="fa-down-to-bracket">:down-to-bracket:</i> [**Downloads**](/download-center/electrical)**:** Download the latest product catalogues, technical datasheets, user guides, certification documents, and firmware updates for your devices.

<i class="fa-supportnow">:supportnow:</i> [**Service & Support**](broken://pages/DNNPxQWk4NA1wNulgtIP)**:** Learn about our warranty policies and after-sales service, or contact our expert team for professional technical assistance.

***

### 🌐 Connect With Us

* **Website:** [www.bituo-technik.com](https://www.bituo-technik.com)
* **Info:** <support@bituo-technik.com>
* **Core Values:** Integrity | Innovation | Openness | Humbleness | Braveness

*Simple and reliable electrical monitoring solutions for everyone.*


# Overview

## Product Overview

**Bituo Technik** is a forward-looking provider of electrical monitoring technologies, with a strong R\&D focus on electrical safety and energy efficiency.

We offer two major product categories:

<table data-header-hidden><thead><tr><th width="127"></th><th></th><th></th></tr></thead><tbody><tr><td></td><td><strong>Electrical Monitoring Devices</strong></td><td><strong>Electrical Measurement Components</strong></td></tr><tr><td><strong>Description</strong></td><td>Smart devices designed for fast, seamless integration into new or existing panels and boxes, ensuring safe, efficient, and connected operation.</td><td>Reliable electronic components and systems for residual current detection and power monitoring &#x26; metering, tailored for renewable energy and industrial applications.</td></tr><tr><td><strong>Products</strong></td><td><ul><li>SPM Series - Miniature Energy Meters</li><li>SDM Series - Compact DIN-Rail Energy Meters</li><li>SRS Series - Smart Relay Switches
</li></ul></td><td><ul><li>BRCS Series - AC/DC Residual Current Sensors for EV Charging</li><li>BSCT Series - Split-Core Current Transformers</li></ul></td></tr></tbody></table>

***

### Electrical Monitoring Devices

{% tabs %}
{% tab title="SPM Series" %}

#### SPM Series — Miniature Energy Meters

> The world's smallest real-time energy monitors with integrated communication, designed to install above or below circuit breakers with no extra DIN rail space required.

**Wireless Communication Variants**

<table><thead><tr><th width="181">Model</th><th>Applicaton</th><th width="143">Voltage</th><th width="107">Max Current</th><th>Connectivity</th></tr></thead><tbody><tr><td><a href="/product-document/spm-series/spm01-flex">SPM01 FLEX</a></td><td>Single-phase</td><td>220–240 VAC</td><td>63 A</td><td>Wi-Fi / Zigbee / BLE</td></tr><tr><td><a href="/product-document/spm-series/spm02-flex">SPM02 FLEX</a></td><td>Three-phase</td><td>220–240 / 380–415 VAC</td><td>63 A</td><td>Wi-Fi / Zigbee / BLE</td></tr><tr><td><a href="/product-document/spm-series/spm01-mcbm">SPM01 MCBM</a></td><td>Single-phase</td><td>220–240 VAC</td><td>63 A</td><td>Wi-Fi / Zigbee / BLE</td></tr><tr><td><a href="/product-document/spm-series/spm02-mcbm">SPM02 MCBM</a></td><td>Three-phase</td><td>220–240 / 380–415 VAC</td><td>63 A</td><td>Wi-Fi / Zigbee / BLE</td></tr></tbody></table>

**Wired Communication Variants**

<table><thead><tr><th width="181">Model</th><th>Applicaton</th><th width="143">Voltage</th><th width="108">Max Current</th><th>Connectivity</th></tr></thead><tbody><tr><td><a href="/product-document/spm-series/spm01r-flex">SPM01R FLEX</a></td><td>Single-phase</td><td>220–240 VAC</td><td>63 A</td><td>Modbus RTU</td></tr><tr><td><a href="/product-document/spm-series/spm02r-flex">SPM02R FLEX</a></td><td>Three-phase</td><td>220–240 / 380–415 VAC</td><td>63 A</td><td>Modbus RTU</td></tr><tr><td><a href="/product-document/spm-series/spm01r-mcbm">SPM01R MCBM</a></td><td>Single-phase</td><td>220–240 VAC</td><td>63 A</td><td>Modbus RTU</td></tr><tr><td><a href="/product-document/spm-series/spm02r-mcbm">SPM02R MCBM</a></td><td>Three-phase</td><td>220–240 / 380–415 VAC</td><td>63 A</td><td>Modbus RTU</td></tr></tbody></table>
{% endtab %}

{% tab title="SDM Series" %}

#### SDM Series — Compact DIN-Rail Energy Meters

> Smart energy meters with split-core clamp CTs. Engineered to meet IEC and UL standards for global markets.

<table><thead><tr><th width="163">Model</th><th>Application</th><th width="183">Voltage</th><th width="178">Max Current</th><th width="196">Connectivity</th></tr></thead><tbody><tr><td><a href="/product-document/sdm-series/sdm01-combo">SDM01 Combo</a></td><td>Three-phase</td><td>220–240 (L-N) / 380–415  (L-L)  VAC</td><td><p>120 A (Ø16 CT)</p><p>200 A (Ø20 CT)<br>300 A (Ø24 CT)<br>400 A (Ø36 CT)</p></td><td><ul><li>Wireless: Wi-Fi / Zigbee / BLE</li><li>Wired: RS485</li></ul></td></tr><tr><td><a href="/product-document/sdm-series/sdm02-sp">SDM02 SP</a></td><td>Split-phase </td><td>110-240 (L-N) / 208-240 (L<sub>1</sub>-L<sub>2</sub>) VAC</td><td><p>120 A (Ø16 CT)</p><p>200 A (Ø20 CT)<br>300 A (Ø24 CT)</p></td><td>Wi-Fi / Zigbee / BLE</td></tr><tr><td>SDM01G2 Combo</td><td>Three-phase</td><td>220–240 (L-N) / 380–415  (L-L)  VAC</td><td><p>50 A (Ø10 CT)<br>120 A (Ø16 CT)</p><p>200 A (Ø20 CT)<br>300 A (Ø24 CT)<br>400 A (Ø36 CT)</p></td><td><p></p><ul><li>Wireless: Wi-Fi / Zigbee / BLE</li><li>Wired: RS485</li></ul></td></tr><tr><td>SDM01G2X</td><td>Three-phase</td><td>220–240 (L-N) / 380–415  (L-L)  VAC</td><td><p>50 A (Ø10 CT)<br>120 A (Ø16 CT)</p><p>200 A (Ø20 CT)<br>300 A (Ø24 CT)<br>400 A (Ø36 CT)</p></td><td>Wi-Fi / Zigbee / BLE / LoRaWAN (External Antenna)</td></tr></tbody></table>
{% endtab %}

{% tab title="SRS Series" %}

#### SRS Series — Smart Relay Switches

> Compact smart relays with integrated power monitoring, designed for flush-mounted wall boxes and ceiling installations.

| Model                                               | Channels                | Max Current                                  | Metering      | Communication        |
| --------------------------------------------------- | ----------------------- | -------------------------------------------- | ------------- | -------------------- |
| [SRS01-1PM](/product-document/srs-series/srs01-1pm) | 1 × relay               | 16 A (Resistive)                             | V / I / P / E | Wi-Fi / Zigbee / BLE |
| [SRS01-2PM](/product-document/srs-series/srs01-2pm) | 2 × relay (independent) | 10 A per channel, max 16 A total (Resistive) | V / I / P / E | Wi-Fi / Zigbee / BLE |
| {% endtab %}                                        |                         |                                              |               |                      |
| {% endtabs %}                                       |                         |                                              |               |                      |

***

### Electrical Measurement Components

{% tabs %}
{% tab title="BRCS Series" %}

#### BRCS Series — AC/DC Residual Current Sensors

> Sensors for built-in RDC/RDC-DD at AC EV charging equipment. World's first TÜV-certified sensor for RDC-DD (2019), and 6+ year proven track records.

<table><thead><tr><th width="117">Model</th><th width="147">Mounting</th><th width="135">Supply</th><th>Residual Current Type</th></tr></thead><tbody><tr><td><a href="/product-document/brcs-series#model-list">BRCS01C</a></td><td>Cable / PCB / Enclosure</td><td>5 V / 12 V</td><td>Type-A 30mA (IEC60947-2-M / IEC61008-1) ; DC 6 mA(IEC 62955); AC 20mA (UL2231-2:CCID20)</td></tr><tr><td><a href="/product-document/brcs-series#model-list">BRCS03C</a></td><td>PCB (copper jumper)</td><td>5 V</td><td>Type-A 30mA (IEC60947-2-M / IEC61008-1) ; DC 6 mA(IEC 62955); AC 20mA (UL2231-2:CCID20)</td></tr><tr><td><a href="/product-document/brcs-series#model-list">BRCS03X</a></td><td>PCB (Horizontal Through-hole)</td><td>5 V</td><td>Type-A 30mA (IEC60947-2-M / IEC61008-1) ; DC 6 mA(IEC 62955); AC 20mA (UL2231-2:CCID20)</td></tr><tr><td><a href="/product-document/brcs-series#model-list">BRCS01V</a></td><td>PCB (Vertical Through-hole)</td><td>5 V</td><td>Type-A 30mA (IEC60947-2-M / IEC61008-1) ; DC 6 mA(IEC 62955); AC 20mA (UL2231-2:CCID20)</td></tr></tbody></table>

> 💡 IEC and UL versions share the same hardware but differ in pin assignments and output logic. Always select the correct version for your target market.
> {% endtab %}

{% tab title="BSCT Series" %}

#### BSCT Series — Split-Core Current Transformers

> High-accuracy split-core CTs with 100% factory accuracy testing. Originally developed for the SDM series, available as standalone components.

<table><thead><tr><th>Model</th><th width="132">Aperture</th><th>Rated Current</th><th>Shell Color</th></tr></thead><tbody><tr><td>BSCT-10A / 10C</td><td>10 mm</td><td>50A/16.6mA</td><td>White / Black</td></tr><tr><td>BSCT-16B / 16C</td><td>16 mm</td><td>120A/40mA</td><td>White / Black</td></tr><tr><td>BSCT-20A</td><td>20 mm</td><td>200A/66.6mA</td><td>White </td></tr><tr><td>BSCT-24C</td><td>24 mm</td><td>300A/50mA</td><td>Black</td></tr><tr><td>BSCT-36C</td><td>36 mm</td><td>400A/66.6mA</td><td>Black</td></tr></tbody></table>

> Custom specifications available upon request.
> {% endtab %}
> {% endtabs %}


# SPM Series

## SPM Series — Miniature Energy Meters

Ultra-compact miniature energy meters with built-in CTs, designed to install directly above or below circuit breakers in final distribution boards — **no DIN rail space required**.

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2F3zv6ocL9sK7phWO9JurZ%2Fimgi_25_F3-1.jpg?alt=media&amp;token=3fb5a8f0-2d00-47bd-92bc-215ae39f793b" alt=""><figcaption></figcaption></figure>

***

### Product Variants

SPM products are defined across **three dimensions**:

#### 1. Product Platform

<table><thead><tr><th width="141"></th><th>SPM01</th><th>SPM02</th></tr></thead><tbody><tr><td><strong>Phase</strong></td><td>Single-phase (1PN)</td><td>Three-phase (3PN)</td></tr><tr><td><strong>Rated Voltage</strong></td><td>220–240 VAC (L-N)</td><td>220–240 VAC (L-N) / 380–415 VAC (L-L)</td></tr><tr><td><strong>Max Current</strong></td><td>63 A</td><td>63 A</td></tr><tr><td><strong>Dimension</strong></td><td>46.8 × 17.8 × 21.3 mm (1MW)</td><td>46.4 × 53.0 × 21.3 mm (3MW)</td></tr><tr><td><strong>Accuracy</strong></td><td>±1% (active energy, resistive load)</td><td>±1% (active energy, resistive load)</td></tr></tbody></table>

#### 2. Installation Style

<table><thead><tr><th width="225"></th><th width="256">FLEX</th><th>MCBM</th></tr></thead><tbody><tr><td><strong>How it mounts</strong></td><td>Via voltage take-off wires — flexible positioning</td><td>Clips directly onto MCB body</td></tr><tr><td><strong>Breaker compatibility</strong></td><td>Universal — all circuit breakers</td><td>Verified with Siemens 5SY/5SL only</td></tr><tr><td><strong>Mounting direction</strong></td><td>N/A</td><td>Top-mounted (U1) or Bottom-mounted (D1) — to match your breaker's wiring direction</td></tr><tr><td><strong>Best for</strong></td><td>Retrofit projects, mixed or unknown breaker brands</td><td>New installations with Siemens 5SY/5SL</td></tr></tbody></table>

> 💡 If unsure about MCB compatibility, always choose **FLEX**.

#### 3. Connectivity

<table><thead><tr><th width="116">Variant</th><th width="137">Communication</th><th width="235">Architecture</th><th>API Style</th><th width="140">Typical Users</th></tr></thead><tbody><tr><td><strong>Tuya Wi-Fi</strong> (<code>*TW</code>)</td><td>Wi-Fi</td><td>BK7231N SoC (Tuya Firmware, Slave) + Metering MCU (Bituo Firmware, Master)</td><td>MQTT(Tuya Proprietary)</td><td>Tuya ecosystem, IoT beginners</td></tr><tr><td><strong>Tuya Zigbee</strong> (<code>*TZ</code>)</td><td>Zigbee</td><td>EFR32MG21 SoC (Tuya Firmware, Slave) + Metering MCU (Bituo Firmware, Master)</td><td>Tuya Proprietary Clusters</td><td>Tuya ecosystem with Zigbee hub</td></tr><tr><td><strong>Open Wi-Fi</strong> (<code>*EW</code>)</td><td>BLE + Wi-Fi</td><td>ESP8685 SoC (Bituo Firmware, Master) + Metering MCU (Bituo Firmware, Slave)</td><td>MQTT, HTTP, UDP, BLE</td><td>DIYers, System Integrators</td></tr><tr><td><strong>Std. Zigbee</strong> (<code>*TZ-U01</code>)</td><td>Zigbee 3.0</td><td>EFR32MG21 SoC (Bituo Firmware, Master) + Metering MCU (Bituo Firmware, Slave)</td><td>Standard Zigbee 3.0 Clusters</td><td>System Integrators, DIYers</td></tr></tbody></table>

***

### Sub Pages

<table><thead><tr><th width="223">Model</th><th>Description</th></tr></thead><tbody><tr><td><a data-mention href="/product-document/spm-series/spm01-flex">SPM01 FLEX</a></td><td>1PN 63A Wireless Communication— Flexible-Installation</td></tr><tr><td><a data-mention href="/product-document/spm-series/spm01-mcbm">SPM01 MCBM</a></td><td>1PN 63A Wireless Communication— MCB-Mounting </td></tr><tr><td><a data-mention href="/product-document/spm-series/spm02-flex">SPM02 FLEX</a></td><td>3PN 63A Wireless Communication— Flexible-Installation</td></tr><tr><td><a data-mention href="/product-document/spm-series/spm02-mcbm">SPM02 MCBM</a></td><td>3PN 63A Wireless Communication— MCB-Mounting</td></tr><tr><td><a data-mention href="/product-document/spm-series/spm01r-flex">SPM01R FLEX</a></td><td>1PN 63A Wired Communication— Flexible-Installation</td></tr><tr><td><a data-mention href="/product-document/spm-series/spm01r-mcbm">SPM01R MCBM</a></td><td>1PN 63A Wired Communication— MCB-Mounting </td></tr><tr><td><a data-mention href="/product-document/spm-series/spm02r-flex">SPM02R FLEX</a></td><td>3PN 63A Wired Communication— Flexible-Installation</td></tr><tr><td><a data-mention href="/product-document/spm-series/spm02r-mcbm">SPM02R MCBM</a></td><td>3PN 63A Wired Communication— MCB-Mounting</td></tr></tbody></table>

***

### Related

[SPM/SDM Zigbee Cluster Reference](/device-api/spm-sdm-zigbee-cluster-reference)

[Modbus TCP Map - ESP32-8685](/device-api/spm-sdm-open-wi-fi-api-overview/modbus-tcp-map-esp32-8685)


# SPM01 FLEX

{% hint style="info" %}
&#x20;**Applies to:** SPM01 FLEX | **Hardware Revision:** V1.0+ | **Last Updated:** 2026-10-03
{% endhint %}

### 1.  Introduction

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWEyojFdAh1qpNJYtQu21%2Fimage.png?alt=media&amp;token=410029b4-5814-491d-b3a9-64adbbe7b884" alt="" width="188"><figcaption></figcaption></figure></div>

The **SPM01 Miniature Energy Meter (Flexible Version)** is the perfect solution for retrofit projects and installations with space or compatibility constraints. Designed for easy installation where traditional MCB-mounting may not be compatible, this flexible energy meter fits seamlessly into existing power distribution boards without requiring DIN-rail space.

#### Product Highlights

* **Space saving**: Fits easily into new or existing power distribution boards without taking DIN-rail space
* **Real-time Monitoring**: Tracks voltage, current, power, and energy for efficient management
* **Large Aperture**: Supports cable sizes up to 16mm² with a 9.6mm aperture for maximal 63A measurement.
* **High-precision Measurement**: Delivers accurate active energy measurements with a tolerance of 1%, ensuring precise monitoring of energy consumption.
* **Seamless Connectivity**: Supports Wi-Fi, Zigbee, and BLE, offering a range of connectivity options for integration into home or industrial energy management systems.
* **Innovative Architecture**: Combines a communication SoC with a metering MCU for OEM/ODM firmware customization

#### Typical Applications

* Energy management systems (EMS) for home and small business&#x20;
* Energy management systems (EMS) for buildings, Infrastructure, and Industry
* Energy monitoring for HVAC system
* Energy monitoring for commercial lighting system

***

### 2. Part Description

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FvGymHfYBxu23bEYMjVwe%2Fimage.png?alt=media&amp;token=f8c3ac3e-4415-4502-851c-e0b0b9da82dd" alt=""><figcaption></figcaption></figure></div>

<table><thead><tr><th width="84.5555419921875">#</th><th width="279.3333740234375">Element</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>Cable for L connection</td><td>Connect to power supply from Line</td></tr><tr><td>2</td><td>Cable for Neutral (N) connection</td><td>Connect to power supply from Neutral</td></tr><tr><td>3</td><td>Through-hole for L wire</td><td>Through-hole for L wire: Ensure the wire(L) passes through the hole.</td></tr><tr><td>4</td><td>Reset button</td><td>Press the button above 5 seconds to enter the pairing mode</td></tr><tr><td>5</td><td>LED indicator</td><td>Shows device operation and network status through different flashing patterns.<sup>1)</sup></td></tr><tr><td>6</td><td>Current flow direction</td><td>Indicates forward / positive power flow for installation</td></tr><tr><td>7</td><td>Product model</td><td>Refer to the 'Ordering Information' section for product selection.</td></tr></tbody></table>

Remark:

1\) Refer to the user guide of your selected models for detailed LED status indicators.

***

### 3. Technical Data

| Parameter                                    | Specification            |
| -------------------------------------------- | ------------------------ |
| Rated operating voltage *U*<sub>n</sub>      | 220-240 VAC, 50/60Hz     |
| Max monitoring current *I*<sub>max</sub>     | 63 A                     |
| Over-voltage category                        | III                      |
| Rated insolating voltage *U*<sub>i</sub>     | 250V                     |
| Rated impulse withstand voltage *U*imp       | 4kV                      |
| Pollution degree                             | 3                        |
| Protection degree                            | IP20                     |
| Energy measurement accuracy                  | ±1%                      |
| Maximum Power consumption                    | ≤ 2VA                    |
| Rated operating temperature                  | -25°C to 70°C            |
| Size: Height x Width x Depth                 | 46.8mm x 17.8mm x 21.3mm |
| Integrated communication option<sup>1)</sup> | BLE; Wi-Fi; Zigbee;      |

**Remark:**\
1\) Four variants of main module available with different connectivity - Tuya WiFI (SPM01-\*TW), Tuya Zigbee (SPM01-\*TZ), Open WiFI (SPM01-\*EW), Standard Zigbee 3.0 (SPM01-\*EW-U01)

***

### 4. Mechanical Outline

**Dimension:** Unit in mm

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FBDqbg2R0QHjJ0Pf59rV3%2Fimage.png?alt=media&amp;token=f2fed826-991c-4aca-9879-602d3ebf1b27" alt=""><figcaption></figcaption></figure>

***

### 5. Electrical Installation&#x20;

#### Wiring Diagram

**⚠️ Safety Remarks:**

* The device must be associated with easily accessible upstream protective devices ‒ such as miniature circuit breakers (MCB).
* The device must be installed, operated, serviced, and maintained **ONLY** by qualified professionals.
* Please read the user guide carefully before installation for detailed wiring diagrams and safety precautions.

<p align="center"><strong>Wiring with 1PN Circuit Breaker</strong></p>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FYpadmXYW055uaZewNfph%2FSPM01-FLEX_DPN-Wiring-All_V2.0_202605.jpg?alt=media&amp;token=7f947654-351a-462a-8e96-0f647c7e8820" alt=""><figcaption></figcaption></figure>

<p align="center"><strong>Wiring with 1-Pole Circuit Breaker</strong></p>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fc1m6pCvQVh2boGNeIGlh%2FSPM01-FLEX_1-Poles-Wiring-All_V2.0_202605.jpg?alt=media&amp;token=bdaec68b-7c3c-4e6d-bbf0-2ac9321a7124" alt=""><figcaption></figcaption></figure>

*Forward Energy Calculation: The energy flowing in the same direction as the energy flow arrow printed on the sensor housing is counted as forward energy.*

#### Installation Video

{% embed url="<https://youtu.be/pwLCzQ5b2yU?si=AfV68zhESDTnFe2s>" %}

***

### 6. User Interface

#### Reset Button

Press and hold for 3–5 seconds to enter pairing mode.

#### LED Indicator

{% tabs %}
{% tab title="Tuya WiFi " %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Device connected - the device is online and functioning normally with cloud connectivity.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect using saved network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Network connected, cloud unreachable - the device is connected to Wi-Fi/Zigbee, but failed to reach the cloud.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr></tbody></table>
{% endtab %}

{% tab title="Tuya Zigbee" %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Device connected - the device is online and functioning normally with cloud connectivity.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect using saved network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Network connected, cloud unreachable - the device is connected to Wi-Fi/Zigbee, but failed to reach the cloud.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr></tbody></table>
{% endtab %}

{% tab title="Standard Zigbee 3.0" %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Zigbee connected, BLE disconnected – the device is connected to a Zigbee network while BLE is turned off or not connected.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect both BLE (if available) and Zigbee using saved settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>BLE connected(if available)  - the LED flashes at 1Hz whenever BLE is connected, regardless of Zigbee status.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr></tbody></table>
{% endtab %}

{% tab title="Open WiFi" %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Wi-Fi connected, BLE disconnected - the device is connected to Wi-Fi while BLE is disconnected.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect both BLE and Wi-Fi using saved settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>BLE connected - the LED flashes at 1Hz whenever BLE is connected, regardless of Wi-Fi status.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr></tbody></table>
{% endtab %}
{% endtabs %}

***

### 7. System Integration

Products equipped with different communication SoC firmwares connect to different systems and cloud platforms. Users can select the appropriate version based on their specific application requirements.

{% tabs %}
{% tab title="Tuya WiFi " %}
The Tuya WiFi version can only be integrated into the Tuya Cloud using Tuya's encrypted MQTT communication. It cannot be directly integrated with any third-party cloud platforms, ecosystems, or gateways. Third-party clouds or edge gateways need to be integrated via Tuya cloud APIs. For details, please refer to Tuya's developer documentation.

**Note:**

1. Tuya's strategy for adjusting the cloud data reporting frequency is not fully disclosed. Based on the latest updates as of April 2026, provided the daily data reporting traffic limit is not exceeded, the fastest expected reporting interval will be between 5 to 15 minutes.
2. Tuya's Smart Life App is user-friendly and straightforward, making it ideal for entry-level smart home users who prefer simplicity and basic energy consumption monitoring.
   {% endtab %}

{% tab title="Tuya Zigbee" %}
For standard operation, the Tuya Zigbee version must be integrated with a Tuya gateway, which then connects to the Tuya Cloud via Tuya's encrypted MQTT communication.

**Note:**

1. Tuya's strategy for adjusting the cloud data reporting frequency is not fully disclosed. Based on the latest updates as of April 2026, provided the daily data reporting traffic limit is not exceeded, the fastest expected reporting interval will be between 5 to 15 minutes.
2. There are unofficial methods available on the market to integrate Tuya Zigbee products with third-party gateways or hubs - such as Home Assistant integration via Zigbee2MQTT. However, please be aware of the following potential issues when using these unofficial integration methods:

* **⚠️Network Congestion:** Tuya's proprietary Zigbee data transmission strategy does not bundle data packets. Consequently, high-frequency reporting of the extensive electrical data types from several energy meters, which generate significantly more data than typical smart home Zigbee devices, can easily cause Zigbee network congestion.
* **⚠️Security Risks:** Integrating with third-party Zigbee gateways using the default global Trust Centre Link Key “*ZigbeeAlliance09*” poses potential information security risks. Therefore, using non-Tuya gateways in commercial projects is highly discouraged. For third-party gateway integration, the **Standard Zigbee 3.0** version with Install Code is strongly recommended.
  {% endtab %}

{% tab title="Standard Zigbee 3.0" %}
The Standard Zigbee 3.0 version can seamlessly connects to third-party gateways. Thanks to the standardized application-layer integration of Zigbee 3.0, it is highly convenient and widely applicable for both residential and commercial building projects.

Currently supported smart home ecosystems include:

* **Home Assistant:** Integration via Zigbee2MQTT ([SPM01](https://www.zigbee2mqtt.io/devices/SPM02-U01.html#bituo-technik-spm02-u01), [SPM02](https://www.zigbee2mqtt.io/devices/SPM02-U01.html#bituo-technik-spm02-u01), [SDM01](https://www.zigbee2mqtt.io/devices/SDM01W-U01.html#bituo-technik-sdm01w-u01), and [SDM02](https://www.zigbee2mqtt.io/devices/SDM02-U01.html#bituo-technik-sdm02-u01))
* **SmartThings:** Integration via the SmartThings Hub driver (officially approved).
* **Homey:** Integration via the [Bituo Technik App ](https://homey.app/en-us/app/com.bituotechnik.iot/BITUO-TECHNIK/)

**You can find information about the commonly used Zigbee Cluster Library on** [**this page**](https://bituo-technik.gitbook.io/hc/device-api/zigbee/spm-sdm-zigbee-profile)**.**
{% endtab %}

{% tab title="Open WiFi" %}
The Open Wi-Fi version of SDM01 provides the following open APIs (refer to the Device API document), enabling users to implement local automation and connect to custom cloud platforms.

1. **Zero-Configuration Discovery Mechanism (LAN Addressing)**
   * **mDNS / DNS-SD:** Supports automatic discovery of the energy meter by EV chargers and PV inverters on the Local Area Network (LAN) without the need for IP scanning.
2. **BLE Near-Field Communication Mode (Offline/Maintenance)**
   * **BLE GATT (Time-limited activation):** Requires PIN code + PAKE algorithm authentication for local high-privilege configuration and network resets. Wakes up on demand and closes upon timeout.
   * **BLE Broadcast (Always-on 24/7):** Unidirectional broadcast of AES-encrypted real-time power data, allowing nearby low-power devices to listen with zero latency and without requiring a connection.
3. **LAN Standard Mode (Ultra-low Latency Device Communication)** *Plaintext or lightweight encryption for local networks.*
   * **Modbus TCP:** Used for local linkage with EV chargers and PV inverters.
   * **Local MQTT:** Used for local integration with open-source smart home ecosystems.
   * **WebSocket (WS) / Raw UDP:** Ultra-high frequency real-time power streaming subscription (enables DLB completion within 1-2 seconds).
   * **HTTP / CoAP:** Suitable for low-frequency parameter configuration and status queries.
4. **Cloud Device Access Layer (Device-to-Cloud / Southbound API)**
   * **MQTTS (MQTT over TLS 1.2/1.3):** Core main communication link.
   * **HTTPS (OTA dedicated):** Exclusively used for downloading large Over-The-Air (OTA) firmware upgrade packages.
     {% endtab %}
     {% endtabs %}

***

### 8. Ordering Information

{% tabs %}
{% tab title="Tuya Wi-Fi" %}

<table><thead><tr><th width="75.7777099609375">#</th><th width="176.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SPM01-D2TW</td><td>SPM01 FLEX 63A/1PN Tuya Wi-Fi</td></tr></tbody></table>
{% endtab %}

{% tab title="Tuya Zigbee" %}

<table><thead><tr><th width="75.7777099609375">#</th><th width="176.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SPM01-D2TZ</td><td>SPM01 FLEX 63A/1PN  Tuya Zigbee</td></tr></tbody></table>
{% endtab %}

{% tab title="Standard Zigbee 3.0" %}

<table><thead><tr><th width="75.7777099609375">#</th><th width="176.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SPM01-D2TZ-U01</td><td>SPM01 FLEX 63A/1PN  Std. Zigbee (EFR32MG21)</td></tr></tbody></table>
{% endtab %}

{% tab title="Open WiFi " %}

<table><thead><tr><th width="75.7777099609375">#</th><th width="176.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SPM01-D2EW</td><td>SPM01 FLEX 63A/1PN Open Wi-Fi (ESP32-8685)</td></tr></tbody></table>
{% endtab %}
{% endtabs %}

***

### 9. FAQ&#x20;

{% content-ref url="/pages/149DFxm5iomFCS9alhv5" %}
[FAQ](/faq/overview)
{% endcontent-ref %}

***

### 10. Troubleshooting

{% content-ref url="/pages/td5Nnli4rm9AAhvTaYLk" %}
[Troubleshooting](/troubleshooting/overview)
{% endcontent-ref %}

***

### 11. Printed Document

<table data-full-width="false"><thead><tr><th width="588.5555419921875">Document</th><th>Download</th></tr></thead><tbody><tr><td>Datasheet</td><td><a href="https://downloads.bituo-technik.com/Datasheet/SPM01-FLEX-All_Datasheet_EN.pdf">⬇️ PDF</a></td></tr><tr><td>User Guide</td><td><a href="https://downloads.bituo-technik.com/User-Guide/SPM0102-TWTZEWUZ-All-in-One_User-Guide_EU6Languages.pdf">⬇️ PDF</a></td></tr></tbody></table>

***

### 12. Explore More


# SPM02 FLEX

{% hint style="info" %}
&#x20;**Applies to:** SPM02 FLEX| **Hardware Revision:** V3.0+ | **Last Updated:** 2026-05-20
{% endhint %}

### 1.  Introduction

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FbrFqFAZ2tKRbHRqTm6FP%2Fimage.png?alt=media&amp;token=234b7a1f-7eda-47d4-97cd-e512ebec6fc8" alt=""><figcaption></figcaption></figure></div>

The **SPM02 Miniature Energy Meter (Flexible version)** is an advanced electrical monitoring device designed for three-phase applications. With its compact size, it is ideal to installed above or below circuit breakers, requiring no space on Din-rails. The SPM02 offers precise, real-time data collection for energy consumption, ensuring seamless integration into energy management systems.

#### Product Highlights

* **Space saving**: Fits easily into new or existing power distribution boards without taking DIN-rail space
* **Real-time Monitoring**: Tracks voltage, current, power, and energy for efficient management&#x20;
* **Large Aperture**: Supports cable sizes up to 16mm² with a 9.6mm aperture for maximal 63A measurement.
* **Accurate Metering:** Delivers accurate active energy measurements with a tolerance of 1%, ensuring precise monitoring of energy consumption.
* **Seamless Connectivity**: Supports Wi-Fi, Zigbee, and BLE, offering a range of connectivity options for integration into home or industrial energy management systems.
* **Innovative Architecture**: Combines a communication SoC with a metering MCU for OEM/ODM firmware customization

#### Typical Applications

* Energy management systems (EMS) for home and small business&#x20;
* Energy management systems (EMS) for buildings, Infrastructure, and Industry
* Energy monitoring for HVAC system
* Energy monitoring for commercial lighting system

***

### 2. Part Description

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FjuxICiDhVYAyxzqG2NoU%2Fimage.png?alt=media&amp;token=ea38231f-a80f-4ee8-9a03-f8d01acc98f8" alt="" width="466"><figcaption></figcaption></figure>

<table><thead><tr><th width="84.5555419921875">#</th><th width="241.7333984375">Element</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>Cable for X connection</td><td>Connect to power supply from Line</td></tr><tr><td>2</td><td>Cable for Y connection</td><td>Connect to power supply from Line</td></tr><tr><td>3</td><td>Cable for Z connection</td><td>Connect to power supply from Line</td></tr><tr><td>4</td><td>Cable for N connection</td><td>Connect to power supply from Neutral (N)</td></tr><tr><td>5</td><td>Through-hole for X wire</td><td>Through-hole for X wire: Ensure the wire (X) passes through the hole.</td></tr><tr><td>6</td><td>Through-hole for Y wire</td><td>Through-hole for Y wire: Ensure the wire (Y) passes through the hole.</td></tr><tr><td>7</td><td>Through-hole for Z wire</td><td>Through-hole for Z wire: Ensure the wire (Z) passes through the hole.</td></tr><tr><td>8</td><td>Reset button</td><td>Press the button above 5 seconds to enter the pairing mode</td></tr><tr><td>9</td><td>LED indicator</td><td>Shows device operation and network status through different flashing patterns.<sup>1)</sup></td></tr><tr><td>10</td><td>Current flow direction</td><td>Indicates forward / positive power flow for installation</td></tr><tr><td>11</td><td>Product model</td><td>Refer to the 'Ordering Information' section for product selection.</td></tr></tbody></table>

Remark:

1\) Refer to the user guide of your selected models for detailed LED status indicators.

***

### 3. Technical Data

| Parameter                                    | Specification                                                      |
| -------------------------------------------- | ------------------------------------------------------------------ |
| Rated operating voltage *U*<sub>n</sub>      | <p>220-240 VAC (L-N), 50/60 Hz <br>380-415 VAC (L-L), 50/60 Hz</p> |
| Max monitoring current *I*<sub>max</sub>     | 63 A                                                               |
| Over-voltage category                        | III                                                                |
| Rated insolating voltage *U*<sub>i</sub>     | 440V                                                               |
| Rated impulse withstand voltage *U*imp       | 4kV                                                                |
| Pollution degree                             | 3                                                                  |
| Protection degree                            | IP20                                                               |
| Energy measurement accuracy                  | ±1%                                                                |
| Maximum Power consumption                    | ≤ 2VA                                                              |
| Rated operating temperature                  | -25°C to 55°C                                                      |
| Size: Height x Width x Depth                 | 46.4x53.0x21.3mm                                                   |
| Integrated communication option<sup>1)</sup> | Modbus RTU (RS485)                                                 |

***

### 4. Mechanical Outline

**Dimension:** Unit in mm

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FjC7iC50OuEyjOpqpAxYJ%2Fimage.png?alt=media&amp;token=b14235bf-f5c9-4d24-94c9-1be6a23a88d2" alt=""><figcaption></figcaption></figure>

***

### 5. Electrical Installation&#x20;

#### Wiring Diagram

**⚠️ Safety Remarks:**

* The device must be associated with easily accessible upstream protective devices ‒ such as miniature circuit breakers (MCB).
* The device must be installed, operated, serviced, and maintained **ONLY** by qualified professionals.
* Please read the user guide carefully before installation for detailed wiring diagrams and safety precautions.

<p align="center"><strong>Wiring with 3PN/4P Circuit Breaker (3P4W System)</strong></p>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fh0QhLYfTXzECfYs1T2Ln%2FSPM01-FLEX_4-Poles-Wiring-All_V1.0.jpg?alt=media&amp;token=36fed1c9-8700-4936-b3fc-34cf8959011b" alt=""><figcaption></figcaption></figure>

<p align="center"><strong>Wiring with 3-Pole Circuit Breaker  (3P4W System)</strong></p>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWEf2HR1OPccLQrK8cu44%2FSPM02-FLEX_3-Poles-Wiring-All_V1.0.jpg?alt=media&amp;token=4955178e-cdde-4f31-8d4e-23bbbf196201" alt=""><figcaption></figcaption></figure>

*Forward Energy Calculation: The energy flowing in the same direction as the energy flow arrow printed on the sensor housing is counted as forward energy.*

#### Installation Video

{% embed url="<https://youtu.be/kfV4ZGXp_dw?si=6BjhNAQ7omTvK8a8>" %}

***

### 6. User Interface

#### Reset Button

Press and hold for above 5 seconds to enter pairing mode.

#### LED Indicator

{% tabs %}
{% tab title="Tuya WiFi " %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Device connected - the device is online and functioning normally with cloud connectivity.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect using saved network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Network connected, cloud unreachable - the device is connected to Wi-Fi/Zigbee, but failed to reach the cloud.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Alarm reminder -<br>The device has detected a fault. Please check the wiring and power supply.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fgjz0xceslVOF4qKWMqa0%2FRed-Flashing-at-1Hz.jpg?alt=media&amp;token=202171d9-496d-4264-9b50-a7ab0d175d0c">Red-Flashing-at-1Hz.jpg</a></td></tr></tbody></table>
{% endtab %}

{% tab title="Tuya Zigbee" %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Device connected - the device is online and functioning normally with cloud connectivity.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect using saved network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Network connected, cloud unreachable - the device is connected to Wi-Fi/Zigbee, but failed to reach the cloud.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Alarm reminder -<br>The device has detected a fault. Please check the wiring and power supply.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fgjz0xceslVOF4qKWMqa0%2FRed-Flashing-at-1Hz.jpg?alt=media&amp;token=202171d9-496d-4264-9b50-a7ab0d175d0c">Red-Flashing-at-1Hz.jpg</a></td></tr></tbody></table>
{% endtab %}

{% tab title="Standard Zigbee 3.0" %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Zigbee connected, BLE disconnected – the device is connected to a Zigbee network while BLE is turned off or not connected.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect both BLE (if available) and Zigbee using saved settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>BLE connected(if available)  - the LED flashes at 1Hz whenever BLE is connected, regardless of Zigbee status.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>The device has detected a fault. Please check the wiring and power supply.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fgjz0xceslVOF4qKWMqa0%2FRed-Flashing-at-1Hz.jpg?alt=media&amp;token=202171d9-496d-4264-9b50-a7ab0d175d0c">Red-Flashing-at-1Hz.jpg</a></td></tr></tbody></table>
{% endtab %}

{% tab title="Open WiFi" %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Wi-Fi connected, BLE disconnected - the device is connected to Wi-Fi while BLE is disconnected.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect both BLE and Wi-Fi using saved settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>BLE connected - the LED flashes at 1Hz whenever BLE is connected, regardless of Wi-Fi status.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Alarm reminder -<br>The device has detected a fault. Please check the wiring and power supply.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fgjz0xceslVOF4qKWMqa0%2FRed-Flashing-at-1Hz.jpg?alt=media&amp;token=202171d9-496d-4264-9b50-a7ab0d175d0c">Red-Flashing-at-1Hz.jpg</a></td></tr></tbody></table>
{% endtab %}
{% endtabs %}

***

### 7. System Integration

Products equipped with different communication SoC firmwares connect to different systems and cloud platforms. Users can select the appropriate version based on their specific application requirements.

{% tabs %}
{% tab title="Tuya WiFi " %}
The Tuya WiFi version can only be integrated into the Tuya Cloud using Tuya's encrypted MQTT communication. It cannot be directly integrated with any third-party cloud platforms, ecosystems, or gateways. Third-party clouds or edge gateways need to be integrated via Tuya cloud APIs. For details, please refer to Tuya's developer documentation.

**Note:**

1. Tuya's strategy for adjusting the cloud data reporting frequency is not fully disclosed. Based on the latest updates as of April 2026, provided the daily data reporting traffic limit is not exceeded, the fastest expected reporting interval will be between 5 to 15 minutes.
2. Tuya's Smart Life App is user-friendly and straightforward, making it ideal for entry-level smart home users who prefer simplicity and basic energy consumption monitoring.
   {% endtab %}

{% tab title="Tuya Zigbee" %}
For standard operation, the Tuya Zigbee version must be integrated with a Tuya gateway, which then connects to the Tuya Cloud via Tuya's encrypted MQTT communication.

**Note:**

1. Tuya's strategy for adjusting the cloud data reporting frequency is not fully disclosed. Based on the latest updates as of April 2026, provided the daily data reporting traffic limit is not exceeded, the fastest expected reporting interval will be between 5 to 15 minutes.
2. There are unofficial methods available on the market to integrate Tuya Zigbee products with third-party gateways or hubs - such as Home Assistant integration via Zigbee2MQTT. However, please be aware of the following potential issues when using these unofficial integration methods:

* **⚠️Network Congestion:** Tuya's proprietary Zigbee data transmission strategy does not bundle data packets. Consequently, high-frequency reporting of the extensive electrical data types from several energy meters, which generate significantly more data than typical smart home Zigbee devices, can easily cause Zigbee network congestion.
* **⚠️Security Risks:** Integrating with third-party Zigbee gateways using the default global Trust Centre Link Key “*ZigbeeAlliance09*” poses potential information security risks. Therefore, using non-Tuya gateways in commercial projects is highly discouraged. For third-party gateway integration, the **Standard Zigbee 3.0** version with Install Code is strongly recommended.
  {% endtab %}

{% tab title="Standard Zigbee 3.0" %}
The Standard Zigbee 3.0 version can seamlessly connects to third-party gateways. Thanks to the standardized application-layer integration of Zigbee 3.0, it is highly convenient and widely applicable for both residential and commercial building projects.

Currently supported smart home ecosystems include:

* **Home Assistant:** Integration via Zigbee2MQTT ([SPM01](https://www.zigbee2mqtt.io/devices/SPM02-U01.html#bituo-technik-spm02-u01), [SPM02](https://www.zigbee2mqtt.io/devices/SPM02-U01.html#bituo-technik-spm02-u01), [SDM01](https://www.zigbee2mqtt.io/devices/SDM01W-U01.html#bituo-technik-sdm01w-u01), and [SDM02](https://www.zigbee2mqtt.io/devices/SDM02-U01.html#bituo-technik-sdm02-u01))
* **SmartThings:** Integration via the SmartThings Hub driver (officially approved).
* **Homey:** Integration via the [Bituo Technik App ](https://homey.app/en-us/app/com.bituotechnik.iot/BITUO-TECHNIK/)

**You can find information about the commonly used Zigbee Cluster Library on** [**this page**](https://bituo-technik.gitbook.io/hc/device-api/zigbee/spm-sdm-zigbee-profile)**.**
{% endtab %}

{% tab title="Open WiFi" %}
The Open Wi-Fi version of SDM01 provides the following open APIs (refer to the Device API document), enabling users to implement local automation and connect to custom cloud platforms.

1. **Zero-Configuration Discovery Mechanism (LAN Addressing)**
   * **mDNS / DNS-SD:** Supports automatic discovery of the energy meter by EV chargers and PV inverters on the Local Area Network (LAN) without the need for IP scanning.
2. **BLE Near-Field Communication Mode (Offline/Maintenance)**
   * **BLE GATT (Time-limited activation):** Requires PIN code + PAKE algorithm authentication for local high-privilege configuration and network resets. Wakes up on demand and closes upon timeout.
   * **BLE Broadcast (Always-on 24/7):** Unidirectional broadcast of AES-encrypted real-time power data, allowing nearby low-power devices to listen with zero latency and without requiring a connection.
3. **LAN Standard Mode (Ultra-low Latency Device Communication)** *Plaintext or lightweight encryption for local networks.*
   * **Modbus TCP:** Used for local linkage with EV chargers and PV inverters.
   * **Local MQTT:** Used for local integration with open-source smart home ecosystems.
   * **WebSocket (WS) / Raw UDP:** Ultra-high frequency real-time power streaming subscription (enables DLB completion within 1-2 seconds).
   * **HTTP / CoAP:** Suitable for low-frequency parameter configuration and status queries.
4. **Cloud Device Access Layer (Device-to-Cloud / Southbound API)**
   * **MQTTS (MQTT over TLS 1.2/1.3):** Core main communication link.
   * **HTTPS (OTA dedicated):** Exclusively used for downloading large Over-The-Air (OTA) firmware upgrade packages.
     {% endtab %}
     {% endtabs %}

***

### 8. Ordering Information

{% tabs %}
{% tab title="Tuya Wi-Fi" %}

<table><thead><tr><th width="75.7777099609375">#</th><th width="176.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SPM02-D2TW</td><td>SPM02 FLEX 63A/3PN Tuya Wi-Fi</td></tr></tbody></table>
{% endtab %}

{% tab title="Tuya Zigbee" %}

<table><thead><tr><th width="75.7777099609375">#</th><th width="176.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SPM02-D2TZ</td><td>SPM02 FLEX 63A/3PN Tuya Zigbee</td></tr></tbody></table>
{% endtab %}

{% tab title="Standard Zigbee 3.0" %}

<table><thead><tr><th width="75.7777099609375">#</th><th width="176.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SPM02-D2TZ-U01</td><td>SPM02 FLEX 63A/3PN Std. Zigbee (EFR32MG21)</td></tr></tbody></table>
{% endtab %}

{% tab title="Open WiFi " %}

<table><thead><tr><th width="75.7777099609375">#</th><th width="176.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SPM02-D2EW</td><td>SPM02 FLEX 63A/3PN Open Wi-Fi (ESP32-8685)</td></tr></tbody></table>
{% endtab %}
{% endtabs %}

***

### 9. FAQ&#x20;

{% content-ref url="/pages/149DFxm5iomFCS9alhv5" %}
[FAQ](/faq/overview)
{% endcontent-ref %}

***

### 10. Troubleshooting

{% content-ref url="/pages/td5Nnli4rm9AAhvTaYLk" %}
[Troubleshooting](/troubleshooting/overview)
{% endcontent-ref %}

### 11. Printed Document

<table data-full-width="false"><thead><tr><th width="588.5555419921875">Document</th><th>Download</th></tr></thead><tbody><tr><td>Datasheet</td><td><a href="https://downloads.bituo-technik.com/Datasheet/SPM02-FLEX-All_Datasheet_EN.pdf">⬇️ PDF</a></td></tr><tr><td>User Guide</td><td><a href="https://downloads.bituo-technik.com/User-Guide/SPM0102-TWTZEWUZ-All-in-One_User-Guide_EU6Languages.pdf">⬇️ PDF</a></td></tr></tbody></table>

### 12. Explore More

/<br>

<br>


# SPM01 MCBM

{% hint style="info" %}
&#x20;**Applies to:** SPM01 MCBM | **Hardware Revision:** V1.0+ | **Last Updated:** 2026-05-06
{% endhint %}

### 1.  Introduction

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fh9SWwGQctnfotpTZo2nF%2Fimage.png?alt=media&amp;token=5bc04893-0a57-4a2e-80b6-9c5db8301085" alt="" width="240"><figcaption></figcaption></figure></div>

The **SPM01 Miniature Energy Meter (MCB-mounting version)** is specifically designed for seamless integration with miniature circuit breakers (MCBs). It ensures easy and efficient energy monitoring within existing electrical systems, delivering real-time data and precise measurement.

#### Product Highlights

* **Space saving:** Installs easily into new or existing distribution boards without occupying DIN-rail space, perfect for crowded panels
* **Real-time Monitoring:** Measures Voltage, Current, Power and Power Factor in real-time to help users optimize energy usage.
* **Large Aperture:** Supports cables up to 16mm² with a 9.6mm aperture, enabling measurement up to 63A.
* **Precise Measurement:** Delivers accurate active energy measurements with a tolerance of 1%, ensuring precise monitoring of energy consumption.
* **Seamless Connectivity**: Supports Wi-Fi, Zigbee, and BLE, offering a range of connectivity options for integration into home or industrial energy management systems.

#### Typical Applications

* Energy management systems (EMS) for home and small business&#x20;
* Energy management systems (EMS) for buildings, Infrastructure, and Industry

### 2. Part Description

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FRCX3MzXHwFEqxPMsk55N%2Fimage.png?alt=media&amp;token=7feff8e7-e01f-4023-a50a-62b04c057acc" alt=""><figcaption></figcaption></figure></div>

<table><thead><tr><th width="84.5555419921875">#</th><th width="279.3333740234375">Element</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>Terminal plate for L connection</td><td>Insert to protective device terminal box for power supply from Line<sup>1)</sup></td></tr><tr><td>2</td><td>Cable for Neutral (N) connection</td><td>Connect to power supply from Neutral</td></tr><tr><td>3</td><td>Through-hole for L wire</td><td>Through-hole for L wire: Ensure the wire(L) passes through the hole.</td></tr><tr><td>4</td><td>Reset button</td><td>Press the button above 5 seconds to enter the pairing mode</td></tr><tr><td>5</td><td>LED indicator</td><td>Shows device operation and network status through different flashing patterns.<sup>2)</sup></td></tr><tr><td>6</td><td>Current flow direction</td><td>Indicates forward / positive power flow for installation</td></tr><tr><td>7</td><td>Product model</td><td>Refer to the 'Ordering Information' section for product selection.</td></tr></tbody></table>

Remark:

1\) The manufacturer has only verified the compatibility of SPM01 MCBM with Siemens 5SY/5SL series, including tests on wiring capacity, thermal performance, and mechanical fit etc. The flexible version is recommended if you are unsure about MCB-mounting compatibility with your circuit breakers.

2\) Refer to the user guide of your selected models for detailed LED status indicators.

### 3. Technical Data

| Parameter                                    | Specification            |
| -------------------------------------------- | ------------------------ |
| Rated operating voltage *U*<sub>n</sub>      | 220-240 VAC, 50/60Hz     |
| Max monitoring current *I*<sub>max</sub>     | 63 A                     |
| Over-voltage category                        | III                      |
| Rated insolating voltage *U*<sub>i</sub>     | 250V                     |
| Rated impulse withstand voltage *U*imp       | 4kV                      |
| Pollution degree                             | 3                        |
| Protection degree                            | IP20                     |
| Energy measurement accuracy                  | ±1%                      |
| Maximum power consumption                    | ≤ 2VA                    |
| Rated operating temperature                  | -25°C to 55°C            |
| Size: Height x Width x Depth                 | 46.8mm x 17.8mm x 21.3mm |
| Integrated communication option<sup>1)</sup> | BLE; WiFi; Zigbee        |

### 4. Mechanical Outline

**Dimension:** Unit in mm

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FTpRAHkzwTsYmrCi7DYEA%2FSPM01-MCBM_Dimensition_EN_V1.1_202605.jpg?alt=media&amp;token=7865e36e-2b88-43c7-b322-41feb7eef597" alt=""><figcaption></figcaption></figure>

### 5. Electrical Installation&#x20;

#### Wiring Diagram

**⚠️ Safety Remarks:**

* The device must be associated with easily accessible upstream protective devices ‒ such as miniature circuit breakers (MCB).
* The device must be installed, operated, serviced, and maintained **ONLY** by qualified professionals.
* Please read the user guide carefully before installation for detailed wiring diagrams and safety precautions.
* The manufacturer has only verified the compatibility of SPM01 MCBM with Siemens 5SY/5SL series, including tests on wiring capacity, thermal performance, and mechanical fit etc. The flexible version is recommended if you are unsure about MCB-mounting compatibility with your circuit breakers.

{% columns %}
{% column %}

<p align="center"><strong>Downstream Installation</strong></p>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2F4PuOwYwgkopcRLYWaGXF%2FSPM01-MCBM-D1_1-Poles-Wiring-All_V2.0_202605.jpg?alt=media&amp;token=61837473-2f32-4a88-a91b-922b133f24f0" alt=""><figcaption></figcaption></figure>
{% endcolumn %}

{% column %}

<p align="center"><strong>Upstream Installation</strong></p>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FRdXn2CtrwR0Pg0sOr7LZ%2FSPM01-MCBM-U1_1-Poles-Wiring-All_V2.0_202605.jpg?alt=media&amp;token=82372724-f6c6-42a6-bfe7-b6d9333e44c9" alt=""><figcaption></figcaption></figure>
{% endcolumn %}
{% endcolumns %}

Forward Energy Calculation: The energy flowing in the same direction as the energy flow arrow printed on the sensor housing is counted as forward energy.

#### Installation Video

*🚧Coming soon...*

### 6. User Interface

#### Reset Button

Press and hold for above 5 seconds to enter pairing mode.

#### LED Indicator

{% tabs %}
{% tab title="Tuya WiFi " %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Device connected - the device is online and functioning normally with cloud connectivity.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect using saved network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Network connected, cloud unreachable - the device is connected to Wi-Fi/Zigbee, but failed to reach the cloud.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr></tbody></table>
{% endtab %}

{% tab title="Tuya Zigbee" %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Device connected - the device is online and functioning normally with cloud connectivity.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect using saved network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Network connected, cloud unreachable - the device is connected to Wi-Fi/Zigbee, but failed to reach the cloud.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr></tbody></table>
{% endtab %}

{% tab title="Standard Zigbee 3.0" %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Zigbee connected, BLE disconnected – the device is connected to a Zigbee network while BLE is turned off or not connected.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect both BLE (if available) and Zigbee using saved settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>BLE connected(if available)  - the LED flashes at 1Hz whenever BLE is connected, regardless of Zigbee status.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr></tbody></table>
{% endtab %}

{% tab title="Open WiFi" %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Wi-Fi connected, BLE disconnected - the device is connected to Wi-Fi while BLE is disconnected.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect both BLE and Wi-Fi using saved settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>BLE connected - the LED flashes at 1Hz whenever BLE is connected, regardless of Wi-Fi status.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr></tbody></table>
{% endtab %}
{% endtabs %}

***

### 7. System Integration

Products equipped with different communication SoC firmwares connect to different systems and cloud platforms. Users can select the appropriate version based on their specific application requirements.

{% tabs %}
{% tab title="Tuya WiFi " %}
The Tuya WiFi version can only be integrated into the Tuya Cloud using Tuya's encrypted MQTT communication. It cannot be directly integrated with any third-party cloud platforms, ecosystems, or gateways. Third-party clouds or edge gateways need to be integrated via Tuya cloud APIs. For details, please refer to Tuya's developer documentation.

**Note:**

1. Tuya's strategy for adjusting the cloud data reporting frequency is not fully disclosed. Based on the latest updates as of April 2026, provided the daily data reporting traffic limit is not exceeded, the fastest expected reporting interval will be between 5 to 15 minutes.
2. Tuya's Smart Life App is user-friendly and straightforward, making it ideal for entry-level smart home users who prefer simplicity and basic energy consumption monitoring.
   {% endtab %}

{% tab title="Tuya Zigbee" %}
For standard operation, the Tuya Zigbee version must be integrated with a Tuya gateway, which then connects to the Tuya Cloud via Tuya's encrypted MQTT communication.

**Note:**

1. Tuya's strategy for adjusting the cloud data reporting frequency is not fully disclosed. Based on the latest updates as of April 2026, provided the daily data reporting traffic limit is not exceeded, the fastest expected reporting interval will be between 5 to 15 minutes.
2. There are unofficial methods available on the market to integrate Tuya Zigbee products with third-party gateways or hubs - such as Home Assistant integration via Zigbee2MQTT. However, please be aware of the following potential issues when using these unofficial integration methods:

* **⚠️Network Congestion:** Tuya's proprietary Zigbee data transmission strategy does not bundle data packets. Consequently, high-frequency reporting of the extensive electrical data types from several energy meters, which generate significantly more data than typical smart home Zigbee devices, can easily cause Zigbee network congestion.
* **⚠️Security Risks:** Integrating with third-party Zigbee gateways using the default global Trust Centre Link Key “*ZigbeeAlliance09*” poses potential information security risks. Therefore, using non-Tuya gateways in commercial projects is highly discouraged. For third-party gateway integration, the **Standard Zigbee 3.0** version with Install Code is strongly recommended.
  {% endtab %}

{% tab title="Standard Zigbee 3.0" %}
The Standard Zigbee 3.0 version can seamlessly connects to third-party gateways. Thanks to the standardized application-layer integration of Zigbee 3.0, it is highly convenient and widely applicable for both residential and commercial building projects.

Currently supported smart home ecosystems include:

* **Home Assistant:** Integration via Zigbee2MQTT ([SPM01](https://www.zigbee2mqtt.io/devices/SPM02-U01.html#bituo-technik-spm02-u01), [SPM02](https://www.zigbee2mqtt.io/devices/SPM02-U01.html#bituo-technik-spm02-u01), [SDM01](https://www.zigbee2mqtt.io/devices/SDM01W-U01.html#bituo-technik-sdm01w-u01), and [SDM02](https://www.zigbee2mqtt.io/devices/SDM02-U01.html#bituo-technik-sdm02-u01))
* **SmartThings:** Integration via the SmartThings Hub driver (officially approved).
* **Homey:** Integration via the [Bituo Technik App ](https://homey.app/en-us/app/com.bituotechnik.iot/BITUO-TECHNIK/)

**You can find information about the commonly used Zigbee Cluster Library on** [**this page**](https://bituo-technik.gitbook.io/hc/device-api/zigbee/spm-sdm-zigbee-profile)**.**
{% endtab %}

{% tab title="Open WiFi" %}
The Open Wi-Fi version of SDM01 provides the following open APIs (refer to the Device API document), enabling users to implement local automation and connect to custom cloud platforms.

1. **Zero-Configuration Discovery Mechanism (LAN Addressing)**
   * **mDNS / DNS-SD:** Supports automatic discovery of the energy meter by EV chargers and PV inverters on the Local Area Network (LAN) without the need for IP scanning.
2. **BLE Near-Field Communication Mode (Offline/Maintenance)**
   * **BLE GATT (Time-limited activation):** Requires PIN code + PAKE algorithm authentication for local high-privilege configuration and network resets. Wakes up on demand and closes upon timeout.
   * **BLE Broadcast (Always-on 24/7):** Unidirectional broadcast of AES-encrypted real-time power data, allowing nearby low-power devices to listen with zero latency and without requiring a connection.
3. **LAN Standard Mode (Ultra-low Latency Device Communication)** *Plaintext or lightweight encryption for local networks.*
   * **Modbus TCP:** Used for local linkage with EV chargers and PV inverters.
   * **Local MQTT:** Used for local integration with open-source smart home ecosystems.
   * **WebSocket (WS) / Raw UDP:** Ultra-high frequency real-time power streaming subscription (enables DLB completion within 1-2 seconds).
   * **HTTP / CoAP:** Suitable for low-frequency parameter configuration and status queries.
4. **Cloud Device Access Layer (Device-to-Cloud / Southbound API)**
   * **MQTTS (MQTT over TLS 1.2/1.3):** Core main communication link.
   * **HTTPS (OTA dedicated):** Exclusively used for downloading large Over-The-Air (OTA) firmware upgrade packages.
     {% endtab %}
     {% endtabs %}

### 8. Ordering Information

{% tabs %}
{% tab title="Tuya Wi-Fi" %}

<table><thead><tr><th width="75.7777099609375">#</th><th width="176.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SPM01-D1TW</td><td>SPM01 MCBM-DI 63A/1PN  Tuya Wi-Fi</td></tr><tr><td>2</td><td>SPM01-U1TW</td><td>SPM01 MCBM-UI 63A/1PN  Tuya Wi-Fi</td></tr></tbody></table>
{% endtab %}

{% tab title="Tuya Zigbee" %}

<table><thead><tr><th width="75.7777099609375">#</th><th width="176.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SPM01-D1TZ</td><td>SPM01 MCBM-DI 63A/1PN  Tuya Zigbee</td></tr><tr><td>2</td><td>SPM01-U1TZ</td><td>SPM01 MCBM-UI 63A/1PN  Tuya Zigbee</td></tr></tbody></table>
{% endtab %}

{% tab title="Standard Zigbee 3.0" %}

<table><thead><tr><th width="75.7777099609375">#</th><th width="176.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SPM01-D1TZ-U01</td><td>SPM01 MCBM-DI 63A/1PN Std. Zigbee (EFR32MG21)</td></tr><tr><td>2</td><td>SPM01-U1TZ-U01</td><td>SPM01 MCBM-UI 63A/1PN Std. Zigbee (EFR32MG21)</td></tr></tbody></table>
{% endtab %}

{% tab title="Open WiFi " %}

<table><thead><tr><th width="75.7777099609375">#</th><th width="176.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SPM01-D1EW</td><td>SPM01 MCBM-DI 63A/1PN  Open Wi-Fi (ESP32-8685)</td></tr><tr><td>2</td><td>SPM01-U1EW</td><td>SPM01 MCBM-UI 63A/1PN  Open Wi-Fi (ESP32-8685)</td></tr></tbody></table>
{% endtab %}
{% endtabs %}

***

### 9. FAQ&#x20;

{% content-ref url="/pages/149DFxm5iomFCS9alhv5" %}
[FAQ](/faq/overview)
{% endcontent-ref %}

***

### 10. Troubleshooting

{% content-ref url="/pages/td5Nnli4rm9AAhvTaYLk" %}
[Troubleshooting](/troubleshooting/overview)
{% endcontent-ref %}

### 11. Printed Document

<table data-full-width="false"><thead><tr><th width="588.5555419921875">Document</th><th>Download</th></tr></thead><tbody><tr><td>Datasheet</td><td><a href="https://downloads.bituo-technik.com/Datasheet/SPM01-MCBM-All_Datasheet_EN.pdf">⬇️ PDF</a></td></tr><tr><td>User Guide</td><td><a href="https://downloads.bituo-technik.com/User-Guide/SPM0102-TWTZEWUZ-All-in-One_User-Guide_EU6Languages.pdf">⬇️ PDF</a></td></tr></tbody></table>

### 12. Explore More

<br>


# SPM02 MCBM

{% hint style="info" %}
&#x20;**Applies to:** SPM02 MCBM | **Hardware Revision:** V3.0+ | **Last Updated:** 2026-05-20
{% endhint %}

### 1.  Introduction

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FMkFuOI7TQqCZTCc5fyxt%2Fimage.png?alt=media&amp;token=74972620-a8a6-4e63-bdf4-1ac3dbfd133d" alt="" width="240"><figcaption></figcaption></figure></div>

The SPM02 **Miniature Energy Meter (MCB-mounting Version)** is an advanced electrical monitoring device designed for three-phase applications, specifically designed for seamless integration with miniature circuit breakers (MCB).

#### Product Highlights

* **Ultra-Compact Installation:** Optimize your panel layout. It mounts directly alongside circuit breakers without consuming valuable DIN-rail space, ideal for high-density distribution boards.
* **Real-Time Power Tracking:** Gain instant visibility into your electrical network. It captures voltage, current, and power factor metrics instantly to help drive energy efficiency strategies.
* **Built for Heavy Loads:** Features a wide 9.6mm aperture that easily accepts up to 16mm² wiring, safely and reliably supporting measurements up to 63A.
* **Uncompromising Precision:** Delivers accurate active energy measurements with a tolerance of 1%, ensuring precise monitoring of energy consumption.
* **Standard Zigbee 3.0 Integration:** Powered by standard Zigbee 3.0. It ensures seamless, cloud-independent connectivity with major smart hubs and gateways for rapid deployment.

#### Typical Applications

* Energy management systems (EMS) for home and small business&#x20;
* Energy management systems (EMS) for buildings, Infrastructure, and Industry
* Energy monitoring for HVAC system
* Energy monitoring for commercial lighting system

### 2. Part Description

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FU8Yx0IjV5ONdkvxzZT0N%2Fimage.png?alt=media&amp;token=27189226-7518-4031-a376-d7c54eed775e" alt=""><figcaption></figcaption></figure>

<table><thead><tr><th width="84.5555419921875">#</th><th width="279.3333740234375">Element</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>Terminal plate for X connection</td><td>Insert to protective device terminal box for power supply from phase<sup>1)</sup></td></tr><tr><td>2</td><td>Terminal plate for Y connection</td><td>Insert to protective device terminal box for power supply from phase<sup>1)</sup></td></tr><tr><td>3</td><td>Terminal plate for Z connection</td><td>Insert to protective device terminal box for power supply from phase<sup>1)</sup></td></tr><tr><td>4</td><td>Cable for N connection</td><td>Connect to power supply from Neutral (N)</td></tr><tr><td>5</td><td>Through-hole for X wire</td><td>Through-hole for X wire: Ensure the wire (X) passes through the hole.</td></tr><tr><td>6</td><td>Through-hole for Y wire</td><td>Through-hole for Y wire: Ensure the wire (Y) passes through the hole.</td></tr><tr><td>7</td><td>Through-hole for Z wire</td><td>Through-hole for Z wire: Ensure the wire (Z) passes through the hole.</td></tr><tr><td>8</td><td>Reset button</td><td>Press the button above 5 seconds to enter the pairing mode</td></tr><tr><td>9</td><td>LED indicator</td><td>Shows device operation and network status through different flashing patterns.<sup>2)</sup></td></tr><tr><td>10</td><td>Power flow direction</td><td>Indicates forward / positive power flow for installation</td></tr><tr><td>11</td><td>Product model</td><td>Refer to the 'Ordering Information' section for product selection.</td></tr></tbody></table>

Remark:

1\) The manufacturer has only verified the compatibility of SPM02 MCBM with Siemens 5SY/5SL series, including tests on wiring capacity, thermal performance, and mechanical fit etc. The flexible version is recommended if you are unsure about MCB-mounting compatibility with your circuit breakers.

2\) Refer to the user guide of your selected models for detailed LED status indicators.

### 3. Technical Data

| Parameter                                    | Specification                                                      |
| -------------------------------------------- | ------------------------------------------------------------------ |
| Rated operating voltage *U*<sub>n</sub>      | <p>220-240 VAC (L-N), 50/60 Hz <br>380-415 VAC (L-L), 50/60 Hz</p> |
| Max monitoring current *I*<sub>max</sub>     | 63 A                                                               |
| Over-voltage category                        | III                                                                |
| Rated insolating voltage *U*<sub>i</sub>     | 440V                                                               |
| Rated impulse withstand voltage *U*imp       | 4kV                                                                |
| Pollution degree                             | 3                                                                  |
| Protection degree                            | IP20                                                               |
| Energy measurement accuracy                  | ±1%                                                                |
| Maximum Power consumption                    | ≤ 2VA                                                              |
| Rated operating temperature                  | -25°C to 70°C                                                      |
| Size: Height x Width x Depth                 | 46.4x53.0x21.3mm                                                   |
| Integrated communication option<sup>1)</sup> | BLE; WiFi; Zigbee                                                  |

### 4. Mechanical Outline

**Dimension:** Unit in mm

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOcCvmgjl2DtFmSQHLnmL%2Fimage.png?alt=media&amp;token=5daa84fa-cd9a-462a-8c7b-815598cef88e" alt="" width="563"><figcaption></figcaption></figure>

### 5. Electrical Installation&#x20;

#### Wiring Diagram

**⚠️ Safety Remarks:**

* The device must be associated with easily accessible upstream protective devices ‒ such as miniature circuit breakers (MCB).
* The device must be installed, operated, serviced, and maintained **ONLY** by qualified professionals.
* Please read the user guide carefully before installation for detailed wiring diagrams and safety precautions.
* The manufacturer has only verified the compatibility of SPM02 MCBM with Siemens 5SY/5SL series, including tests on wiring capacity, thermal performance, and mechanical fit etc. The flexible version is recommended if you are unsure about MCB-mounting compatibility with your circuit breakers.

{% columns %}
{% column width="50%" %}

<p align="center"><strong>Downstream Installation</strong></p>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FmSrEHEzenk2VsY2gRF5d%2FSPM02-MCBM-Downstream_EN_V1.0_202605.jpg?alt=media&amp;token=d4e65eb5-6235-4661-8aeb-cd41ac79d183" alt=""><figcaption></figcaption></figure>
{% endcolumn %}

{% column width="50%" %}

<p align="center"><strong>Upstream Installation</strong><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FFIDj2jKkY6ctTibJNoY6%2FSPM02-MCBM-Upstream_EN_V1.0_202605.jpg?alt=media&amp;token=be262f0d-87f1-4545-b89b-f096389ac7b7" alt=""></p>
{% endcolumn %}
{% endcolumns %}

*Forward Energy Calculation: The energy flowing in the same direction as the energy flow arrow printed on the sensor housing is counted as forward energy.*

#### Installation Video

*🚧Coming soon...*

### 6. User Interface

#### Reset Button

Press and hold for above 5 seconds to enter pairing mode.

#### LED Indicator

{% tabs %}
{% tab title="Tuya WiFi " %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Device connected - the device is online and functioning normally with cloud connectivity.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect using saved network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Network connected, cloud unreachable - the device is connected to Wi-Fi/Zigbee, but failed to reach the cloud.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Alarm reminder -<br>The device has detected a fault. Please check the wiring and power supply.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fgjz0xceslVOF4qKWMqa0%2FRed-Flashing-at-1Hz.jpg?alt=media&amp;token=202171d9-496d-4264-9b50-a7ab0d175d0c">Red-Flashing-at-1Hz.jpg</a></td></tr></tbody></table>
{% endtab %}

{% tab title="Tuya Zigbee" %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Device connected - the device is online and functioning normally with cloud connectivity.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect using saved network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Network connected, cloud unreachable - the device is connected to Wi-Fi/Zigbee, but failed to reach the cloud.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Alarm reminder -<br>The device has detected a fault. Please check the wiring and power supply.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fgjz0xceslVOF4qKWMqa0%2FRed-Flashing-at-1Hz.jpg?alt=media&amp;token=202171d9-496d-4264-9b50-a7ab0d175d0c">Red-Flashing-at-1Hz.jpg</a></td></tr></tbody></table>
{% endtab %}

{% tab title="Standard Zigbee 3.0" %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Zigbee connected, BLE disconnected – the device is connected to a Zigbee network while BLE is turned off or not connected.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect both BLE (if available) and Zigbee using saved settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>BLE connected(if available)  - the LED flashes at 1Hz whenever BLE is connected, regardless of Zigbee status.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>The device has detected a fault. Please check the wiring and power supply.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fgjz0xceslVOF4qKWMqa0%2FRed-Flashing-at-1Hz.jpg?alt=media&amp;token=202171d9-496d-4264-9b50-a7ab0d175d0c">Red-Flashing-at-1Hz.jpg</a></td></tr></tbody></table>
{% endtab %}

{% tab title="Open WiFi" %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Wi-Fi connected, BLE disconnected - the device is connected to Wi-Fi while BLE is disconnected.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect both BLE and Wi-Fi using saved settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>BLE connected - the LED flashes at 1Hz whenever BLE is connected, regardless of Wi-Fi status.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Alarm reminder -<br>The device has detected a fault. Please check the wiring and power supply.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fgjz0xceslVOF4qKWMqa0%2FRed-Flashing-at-1Hz.jpg?alt=media&amp;token=202171d9-496d-4264-9b50-a7ab0d175d0c">Red-Flashing-at-1Hz.jpg</a></td></tr></tbody></table>
{% endtab %}
{% endtabs %}

***

### 7. System Integration

Products equipped with different communication SoC firmwares connect to different systems and cloud platforms. Users can select the appropriate version based on their specific application requirements.

{% tabs %}
{% tab title="Tuya WiFi " %}
The Tuya WiFi version can only be integrated into the Tuya Cloud using Tuya's encrypted MQTT communication. It cannot be directly integrated with any third-party cloud platforms, ecosystems, or gateways. Third-party clouds or edge gateways need to be integrated via Tuya cloud APIs. For details, please refer to Tuya's developer documentation.

**Note:**

1. Tuya's strategy for adjusting the cloud data reporting frequency is not fully disclosed. Based on the latest updates as of April 2026, provided the daily data reporting traffic limit is not exceeded, the fastest expected reporting interval will be between 5 to 15 minutes.
2. Tuya's Smart Life App is user-friendly and straightforward, making it ideal for entry-level smart home users who prefer simplicity and basic energy consumption monitoring.
   {% endtab %}

{% tab title="Tuya Zigbee" %}
For standard operation, the Tuya Zigbee version must be integrated with a Tuya gateway, which then connects to the Tuya Cloud via Tuya's encrypted MQTT communication.

**Note:**

1. Tuya's strategy for adjusting the cloud data reporting frequency is not fully disclosed. Based on the latest updates as of April 2026, provided the daily data reporting traffic limit is not exceeded, the fastest expected reporting interval will be between 5 to 15 minutes.
2. There are unofficial methods available on the market to integrate Tuya Zigbee products with third-party gateways or hubs - such as Home Assistant integration via Zigbee2MQTT. However, please be aware of the following potential issues when using these unofficial integration methods:

* **⚠️Network Congestion:** Tuya's proprietary Zigbee data transmission strategy does not bundle data packets. Consequently, high-frequency reporting of the extensive electrical data types from several energy meters, which generate significantly more data than typical smart home Zigbee devices, can easily cause Zigbee network congestion.
* **⚠️Security Risks:** Integrating with third-party Zigbee gateways using the default global Trust Centre Link Key “*ZigbeeAlliance09*” poses potential information security risks. Therefore, using non-Tuya gateways in commercial projects is highly discouraged. For third-party gateway integration, the **Standard Zigbee 3.0** version with Install Code is strongly recommended.
  {% endtab %}

{% tab title="Standard Zigbee 3.0" %}
The Standard Zigbee 3.0 version can seamlessly connects to third-party gateways. Thanks to the standardized application-layer integration of Zigbee 3.0, it is highly convenient and widely applicable for both residential and commercial building projects.

Currently supported smart home ecosystems include:

* **Home Assistant:** Integration via Zigbee2MQTT ([SPM01](https://www.zigbee2mqtt.io/devices/SPM02-U01.html#bituo-technik-spm02-u01), [SPM02](https://www.zigbee2mqtt.io/devices/SPM02-U01.html#bituo-technik-spm02-u01), [SDM01](https://www.zigbee2mqtt.io/devices/SDM01W-U01.html#bituo-technik-sdm01w-u01), and [SDM02](https://www.zigbee2mqtt.io/devices/SDM02-U01.html#bituo-technik-sdm02-u01))
* **SmartThings:** Integration via the SmartThings Hub driver (officially approved).
* **Homey:** Integration via the [Bituo Technik App ](https://homey.app/en-us/app/com.bituotechnik.iot/BITUO-TECHNIK/)

**You can find information about the commonly used Zigbee Cluster Library on** [**this page**](https://bituo-technik.gitbook.io/hc/device-api/zigbee/spm-sdm-zigbee-profile)**.**
{% endtab %}

{% tab title="Open WiFi" %}
The Open Wi-Fi version of SDM01 provides the following open APIs (refer to the Device API document), enabling users to implement local automation and connect to custom cloud platforms.

1. **Zero-Configuration Discovery Mechanism (LAN Addressing)**
   * **mDNS / DNS-SD:** Supports automatic discovery of the energy meter by EV chargers and PV inverters on the Local Area Network (LAN) without the need for IP scanning.
2. **BLE Near-Field Communication Mode (Offline/Maintenance)**
   * **BLE GATT (Time-limited activation):** Requires PIN code + PAKE algorithm authentication for local high-privilege configuration and network resets. Wakes up on demand and closes upon timeout.
   * **BLE Broadcast (Always-on 24/7):** Unidirectional broadcast of AES-encrypted real-time power data, allowing nearby low-power devices to listen with zero latency and without requiring a connection.
3. **LAN Standard Mode (Ultra-low Latency Device Communication)** *Plaintext or lightweight encryption for local networks.*
   * **Modbus TCP:** Used for local linkage with EV chargers and PV inverters.
   * **Local MQTT:** Used for local integration with open-source smart home ecosystems.
   * **WebSocket (WS) / Raw UDP:** Ultra-high frequency real-time power streaming subscription (enables DLB completion within 1-2 seconds).
   * **HTTP / CoAP:** Suitable for low-frequency parameter configuration and status queries.
4. **Cloud Device Access Layer (Device-to-Cloud / Southbound API)**
   * **MQTTS (MQTT over TLS 1.2/1.3):** Core main communication link.
   * **HTTPS (OTA dedicated):** Exclusively used for downloading large Over-The-Air (OTA) firmware upgrade packages.
     {% endtab %}
     {% endtabs %}

### 8. Ordering Information

{% tabs %}
{% tab title="Tuya Wi-Fi" %}

<table><thead><tr><th width="75.7777099609375">#</th><th width="176.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SPM02-D1TW</td><td>SPM02 MCBM-DI 63A/3PN  Tuya Wi-Fi</td></tr><tr><td>2</td><td>SPM02-U1TW</td><td>SPM02 MCBM-UI 63A/3PN  Tuya Wi-Fi</td></tr></tbody></table>
{% endtab %}

{% tab title="Tuya Zigbee" %}

<table><thead><tr><th width="75.7777099609375">#</th><th width="176.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SPM02-D1TZ</td><td>SPM02 MCBM-DI 63A/3PN  Tuya Zigbee</td></tr><tr><td>2</td><td>SPM02-U1TZ</td><td>SPM02 MCBM-UI 63A/3PN  Tuya Zigbee</td></tr></tbody></table>
{% endtab %}

{% tab title="Standard Zigbee 3.0" %}

<table><thead><tr><th width="75.7777099609375">#</th><th width="176.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SPM02-D1TZ-U01</td><td>SPM02 MCBM-DI 63A/3PN  Std. Zigbee (EFR32MG21)</td></tr><tr><td>2</td><td>SPM02-U1TZ-U01</td><td>SPM02 MCBM-UI 63A/3PN  Std. Zigbee (EFR32MG21)</td></tr></tbody></table>
{% endtab %}

{% tab title="Open WiFi " %}

<table><thead><tr><th width="75.7777099609375">#</th><th width="176.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SPM02-D1EW</td><td>SPM02 MCBM-DI 63A/3PN  Open Wi-Fi (ESP32-8685)</td></tr><tr><td>2</td><td>SPM02-U1EW</td><td>SPM02 MCBM-UI 63A/3PN  Open Wi-Fi (ESP32-8685)</td></tr></tbody></table>
{% endtab %}
{% endtabs %}

### 9. FAQ&#x20;

{% content-ref url="/pages/149DFxm5iomFCS9alhv5" %}
[FAQ](/faq/overview)
{% endcontent-ref %}

***

### 10. Troubleshooting

{% content-ref url="/pages/td5Nnli4rm9AAhvTaYLk" %}
[Troubleshooting](/troubleshooting/overview)
{% endcontent-ref %}

### 11. Printed User Guide

<table data-full-width="false"><thead><tr><th width="588.5555419921875">Document</th><th>Download</th></tr></thead><tbody><tr><td>Datasheet</td><td><a href="https://downloads.bituo-technik.com/Datasheet/SPM02-MCBM-All_Datasheet_EN.pdf">⬇️ PDF</a></td></tr><tr><td>User Guide</td><td><a href="https://downloads.bituo-technik.com/User-Guide/SPM0102-TWTZEWUZ-All-in-One_User-Guide_EU6Languages.pdf">⬇️ PDF</a></td></tr></tbody></table>

### 12. Explore More


# SPM01R FLEX

{% hint style="info" %}
&#x20;**Applies to:** SPM01R FLEX | **Hardware Revision:** V1.0+ | **Last Updated:** 2026-07-18
{% endhint %}

### 1.  Introduction

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fzh0CgGHRvsoSI6UsZaDO%2FSPM01-FLEX-485-%E9%95%BF%E7%BA%BF%E5%9B%BE%E7%89%87%E6%AC%BE_2212.png?alt=media&amp;token=afa526ef-a844-4517-a515-640322bb280b" alt="" width="188"><figcaption></figcaption></figure></div>

The SPM01R Miniature Energy Meter (Flexible Version) is the perfect solution for retrofit projects and installations with space constraints. Requiring no DIN-rail space, this flexible meter features robust Modbus RTU (RS485) communication, delivering precise, real-time 1-phase energy data through a secure and reliable wired network.

#### Product Highlights

* **Space saving:** Fits easily into new or existing power distribution boards without taking DIN-rail space.
* **Real-time Monitoring:** Tracks voltage, current, power, and energy for efficient management.
* **Large Aperture:** Supports cable sizes up to 16mm² with a 9.6mm aperture for maximal 63A measurement.
* **High-precision Measurement:** Delivers accurate active energy measurements with a tolerance of 1%, ensuring precise monitoring of energy consumption.
* **Reliable Connectivity:** Features a 4kV isolated Modbus RTU (RS485) interface for safe, stable, and interference-free integration.

#### Typical Applications

* Energy management systems (EMS) for buildings, Infrastructure, and Industry

***

### 2. Part Description

<div align="center"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOswRsdn7LNiJpIeYdWN1%2Fimage.png?alt=media&amp;token=44d6aa86-3062-4339-a1fa-e316d5767fd5" alt="" width="288"><figcaption></figcaption></figure></div>

<table><thead><tr><th width="84.5555419921875">#</th><th width="279.3333740234375">Element</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>Cable for L connection</td><td>Connect to power supply from Line</td></tr><tr><td>2</td><td>Cable for Neutral (N) connection</td><td>Connect to power supply from Neutral</td></tr><tr><td>3</td><td>Through-hole for L wire</td><td>Through-hole for L wire: Ensure the wire(L) passes through the hole.</td></tr><tr><td>4</td><td>Reset button</td><td>Press and hold for above 5 seconds to reset communication settings to default.</td></tr><tr><td>5</td><td>LED indicator</td><td>Shows device operation and communication status through different flashing patterns.<sup>1)</sup></td></tr><tr><td>6</td><td>Current flow direction</td><td>Indicates forward / positive power flow for installation</td></tr><tr><td>7</td><td>Product model</td><td>Refer to the 'Ordering Information' section for product selection.</td></tr><tr><td>8</td><td>RS485 communication wire</td><td>White wire: RS485-A<br>Blue wire: RS485-B</td></tr></tbody></table>

Remark:

1\) Refer to the user guide of your selected models for detailed LED status indicators.

***

### 3. Technical Data

| Parameter                                | Specification            |
| ---------------------------------------- | ------------------------ |
| Rated operating voltage *U*<sub>n</sub>  | 220-240 VAC, 50/60Hz     |
| Max monitoring current *I*<sub>max</sub> | 63 A                     |
| Over-voltage category                    | III                      |
| Rated insolating voltage *U*<sub>i</sub> | 250V                     |
| Rated impulse withstand voltage *U*imp   | 4kV                      |
| Pollution degree                         | 3                        |
| Protection degree                        | IP20                     |
| Energy measurement accuracy              | ±1%                      |
| Maximum Power consumption                | ≤ 2VA                    |
| Rated operating temperature              | -25°C to 55°C            |
| Size: Height x Width x Depth             | 46.8mm x 17.8mm x 21.3mm |
| Integrated communication option          | Modbus RTU (RS485)       |

***

### 4. Mechanical Outline

**Dimension:** Unit in mm

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FxLuwFuJsSimz8M52Q3yZ%2Fimage.png?alt=media&amp;token=c96b6dca-13fb-4289-b02d-209a8b2acf69" alt="" width="563"><figcaption></figcaption></figure>

***

### 5. Electrical Installation&#x20;

#### Wiring Diagram

**⚠️ Safety Remarks:**

* The device must be associated with easily accessible upstream protective devices ‒ such as miniature circuit breakers (MCB).
* The device must be installed, operated, serviced, and maintained **ONLY** by qualified professionals.
* Please read the user guide carefully before installation for detailed wiring diagrams and safety precautions.

The device comes with 400mm twisted white (RS485-A) and blue (RS485-B) wires. For long-distance RS485 communication, it is recommended to trim these wires short and splice them to a standard shielded twisted-pair cable.

<p align="center"><strong>Wiring with 1PN Circuit Breaker</strong></p>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOuxh36uCIvvX0gsnNjvP%2Fimage.png?alt=media&amp;token=deebfa88-7fe7-409b-8b0e-fc9491f44f4b" alt=""><figcaption></figcaption></figure>

<p align="center"><strong>Wiring with 1-Pole Circuit Breaker</strong></p>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FTLxDQy4D8hKTgDHEcd8V%2Fimage.png?alt=media&amp;token=16d7d9a6-a9a2-42ed-b910-3278d2502589" alt=""><figcaption></figcaption></figure>

*Forward Energy Calculation: The energy flowing in the same direction as the energy flow arrow printed on the sensor housing is counted as forward energy.*

#### Installation Video

*🚧Coming soon...*

***

### 6. User Interface

#### Reset Button

Press and hold for above 5 seconds to reset communication settings to the following factory default:

* **Modbus Address:** 247
* **Baud Rate:** 9600 bps
* **Data Format:** N, 8, 1 (No parity, 8 data bits, 1 stop bit)

#### LED Indicator

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Flashing at 1Hz</strong></td><td>Data transmitting - Flashes 3 times per exchange. Flashes continuously if polling interval is &#x3C;3s.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>Standby (No data exchange)</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr></tbody></table>

***

### 7. System Integration

The Modbus RTU (RS485) version utilizes a standard, open industrial communication protocol. It can be directly integrated into a wide range of third-party systems, including PLCs, edge gateways, data loggers, SCADA, and Building Management Systems (BMS). Unlike cloud-dependent versions, it operates entirely locally and requires a wired connection to a Modbus master device to poll and collect data. For register maps and communication parameters, please refer to the provided Modbus protocol documentation.

**Device Commissioning**

To integrate the meter into your RS485 network, you can configure the Modbus address using one of the following two methods:

**Method 1: Point-to-Point Configuration (Default Settings)** Connect a single device to your master device and configure it using the factory default settings (Modbus Address: `247`, Baud Rate: `9600 bps`, `N, 8, 1`). You can reset the device to these defaults at any time by pressing and holding the Reset button for over 5 seconds.

**Method 2: Broadcast Address Assignment (Button Triggered)** This feature allows for quick commissioning of multiple devices on the same bus without needing to wire and configure them one by one.

Send this command to **Broadcast Address `0`**:

| Address (DEC) | Address (HEX) | Description                              | Func Code | R/W | Data Type | Write Value                |
| ------------- | ------------- | ---------------------------------------- | --------- | --- | --------- | -------------------------- |
| 30000         | `0x7530`      | Assign Modbus Address (Button Triggered) | 10        | W   | 2× UINT16 | `0x55AA` + `[New Address]` |

**How to use Broadcast Address Assignment:**

1. The Host PLC sends a broadcast write command (Slave ID = `0`) to register `30000`.
2. The payload must be 2 words (4 bytes): `0x55AA` followed by the `[New Address]` (e.g., `0x0005`).
3. **Action:** Only the meter that currently has its **physical reset button pressed** will accept this command and update its address. All other meters on the bus will ignore it.

***

### 8. Ordering Information

<table><thead><tr><th width="75.7777099609375">#</th><th width="176.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SPM01-D2M1</td><td>SPM01 FLEX 63A/1PN  Modbus RTU</td></tr></tbody></table>

***

### 9. FAQ&#x20;

{% content-ref url="/pages/149DFxm5iomFCS9alhv5" %}
[FAQ](/faq/overview)
{% endcontent-ref %}

***

### 10. Troubleshooting

{% content-ref url="/pages/td5Nnli4rm9AAhvTaYLk" %}
[Troubleshooting](/troubleshooting/overview)
{% endcontent-ref %}

***

### 11. Printed Document

<table data-full-width="false"><thead><tr><th width="588.5555419921875">Document</th><th>Download</th></tr></thead><tbody><tr><td>Datasheet</td><td><a href="https://downloads.bituo-technik.com/Datasheet/SPM01R-FLEX-All_Datasheet_EN.pdf">⬇️ PDF</a></td></tr><tr><td>User Guide</td><td><a href="https://downloads.bituo-technik.com/User-Guide/SPM01R02R-All-in-One_User-Guide_ENCN.pdf">⬇️ PDF</a></td></tr></tbody></table>

***

### 12. Explore More


# SPM02R FLEX

{% hint style="info" %}
&#x20;**Applies to:** SPM02R FLEX | **Hardware Revision:** V3.0+ | **Last Updated:** 2026-07-18
{% endhint %}

### 1.  Introduction

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FVqxxqMinoZh7unw1WUDY%2Fimage.png?alt=media&amp;token=ac4f7ac3-6b53-4c09-9ec0-0588e8b9a1bb" alt="" width="170"><figcaption></figcaption></figure></div>

Built for advanced 3-phase applications, the SPM02R Miniature Energy Meter (Flexible Version) is ideal for installation above or below circuit breakers, requiring no DIN-rail space. Equipped with a reliable Modbus RTU (RS485) interface, it guarantees stable, accurate data collection via a robust wired connection.

#### Product Highlights

* **Space saving**: Fits easily into new or existing power distribution boards without taking DIN-rail space
* **Real-time Monitoring**: Tracks voltage, current, power, and energy for efficient management&#x20;
* **Large Aperture**: Supports cable sizes up to 16mm² with a 9.6mm aperture for maximal 63A measurement.
* **Accurate Metering:** Delivers accurate active energy measurements with a tolerance of 1%, ensuring precise monitoring of energy consumption.
* **Isolated Connectivity:** Features a 4kV isolated Modbus RTU (RS485) interface for safe, stable, and interference-free integration.

#### Typical Applications

* Energy management systems (EMS) for buildings, Infrastructure, and Industry

***

### 2. Part Description

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FZGAYMBUwuXt2mxFMUEXh%2Fimage.png?alt=media&amp;token=5ea227ef-7cd2-4d86-a6e1-f0b75ec2d4fd" alt="" width="370"><figcaption></figcaption></figure>

<table><thead><tr><th width="84.5555419921875">#</th><th width="241.7333984375">Element</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>Cable for X connection</td><td>Connect to power supply from Line</td></tr><tr><td>2</td><td>Cable for Y connection</td><td>Connect to power supply from Line</td></tr><tr><td>3</td><td>Cable for Z connection</td><td>Connect to power supply from Line</td></tr><tr><td>4</td><td>Cable for N connection</td><td>Connect to power supply from Neutral (N)</td></tr><tr><td>5</td><td>Through-hole for X wire</td><td>Through-hole for X wire: Ensure the wire (X) passes through the hole.</td></tr><tr><td>6</td><td>Through-hole for Y wire</td><td>Through-hole for Y wire: Ensure the wire (Y) passes through the hole.</td></tr><tr><td>7</td><td>Through-hole for Z wire</td><td>Through-hole for Z wire: Ensure the wire (Z) passes through the hole.</td></tr><tr><td>8</td><td>Reset button</td><td>Press and hold for above 5 seconds to reset communication settings to default.</td></tr><tr><td>9</td><td>LED indicator</td><td>Shows device operation and network status through different flashing patterns.<sup>1)</sup></td></tr><tr><td>10</td><td>Current flow direction</td><td>Indicates forward / positive power flow for installation</td></tr><tr><td>11</td><td>Product model</td><td>Refer to the 'Ordering Information' section for product selection.</td></tr><tr><td>12</td><td>RS485 communication wire</td><td>White wire: RS485-A
<br>Blue wire: RS485-B</td></tr></tbody></table>

Remark:

1\) Refer to the user guide of your selected models for detailed LED status indicators.

***

### 3. Technical Data

| Parameter                                    | Specification                                                      |
| -------------------------------------------- | ------------------------------------------------------------------ |
| Rated operating voltage *U*<sub>n</sub>      | <p>220-240 VAC (L-N), 50/60 Hz <br>380-415 VAC (L-L), 50/60 Hz</p> |
| Max monitoring current *I*<sub>max</sub>     | 63 A                                                               |
| Over-voltage category                        | III                                                                |
| Rated insolating voltage *U*<sub>i</sub>     | 440V                                                               |
| Rated impulse withstand voltage *U*imp       | 4kV                                                                |
| Pollution degree                             | 3                                                                  |
| Protection degree                            | IP20                                                               |
| Energy measurement accuracy                  | ±1%                                                                |
| Maximum Power consumption                    | ≤ 2VA                                                              |
| Rated operating temperature                  | -25°C to 55°C                                                      |
| Size: Height x Width x Depth                 | 46.4x53.0x21.3mm                                                   |
| Integrated communication option<sup>1)</sup> | Modbus RTU (RS485)                                                 |

***

### 4. Mechanical Outline

**Dimension:** Unit in mm

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOqAfy6rF7c3MwygAO3eQ%2Fimage.png?alt=media&amp;token=66cb6ce9-5ec6-4d72-bd7b-df424327f6fa" alt=""><figcaption></figcaption></figure>

***

### 5. Electrical Installation&#x20;

#### Wiring Diagram

**⚠️ Safety Remarks:**

* The device must be associated with easily accessible upstream protective devices ‒ such as miniature circuit breakers (MCB).
* The device must be installed, operated, serviced, and maintained **ONLY** by qualified professionals.
* Please read the user guide carefully before installation for detailed wiring diagrams and safety precautions.

The device comes with 400mm twisted white (RS485-A) and blue (RS485-B) wires. For long-distance RS485 communication, it is recommended to trim these wires short and splice them to a standard shielded twisted-pair cable.

<p align="center"><strong>Wiring with 3PN/4P Circuit Breaker (3P4W System)</strong></p>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FdxU9udZgCOqHmz41l1PT%2Fimage.png?alt=media&amp;token=e7ba66c7-a9c2-4d06-ad24-6d1075394219" alt=""><figcaption></figcaption></figure>

<p align="center"><strong>Wiring with 3-Pole Circuit Breaker  (3P4W System)</strong></p>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fv7eGCHZEEmGXwGkAKeiK%2Fimage.png?alt=media&amp;token=bf014fa7-c8f9-441b-b299-cee911055207" alt=""><figcaption></figcaption></figure>

*Forward Energy Calculation: The energy flowing in the same direction as the energy flow arrow printed on the sensor housing is counted as forward energy.*

#### Installation Video

*🚧Coming soon...*

***

### 6. User Interface

#### Reset Button

Press and hold for above 5 seconds to reset communication settings to the following factory default:

* **Modbus Address:** 247
* **Baud Rate:** 9600 bps
* **Data Format:** N, 8, 1 (No parity, 8 data bits, 1 stop bit)

#### LED Indicator

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Flashing at 1Hz</strong></td><td>Data transmitting - Flashes 3 times per exchange. Flashes continuously if polling interval is &#x3C;3s.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>Standby (No data exchange)</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Fault Alarm - Fault detected. Please check wiring and power supply.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fgjz0xceslVOF4qKWMqa0%2FRed-Flashing-at-1Hz.jpg?alt=media&amp;token=202171d9-496d-4264-9b50-a7ab0d175d0c">Red-Flashing-at-1Hz.jpg</a></td></tr></tbody></table>

***

### 7. System Integration

The Modbus RTU (RS485) version utilizes a standard, open industrial communication protocol. It can be directly integrated into a wide range of third-party systems, including PLCs, edge gateways, data loggers, SCADA, and Building Management Systems (BMS). Unlike cloud-dependent versions, it operates entirely locally and requires a wired connection to a Modbus master device to poll and collect data. For register maps and communication parameters, please refer to the provided Modbus protocol documentation.

**Device Commissioning**

To integrate the meter into your RS485 network, you can configure the Modbus address using one of the following two methods:

**Method 1: Point-to-Point Configuration (Default Settings)** Connect a single device to your master device and configure it using the factory default settings (Modbus Address: `247`, Baud Rate: `9600 bps`, `N, 8, 1`). You can reset the device to these defaults at any time by pressing and holding the Reset button for over 5 seconds.

**Method 2: Broadcast Address Assignment (Button Triggered)** This feature allows for quick commissioning of multiple devices on the same bus without needing to wire and configure them one by one.

Send this command to **Broadcast Address `0`**:

| Address (DEC) | Address (HEX) | Description                              | Func Code | R/W | Data Type | Write Value                |
| ------------- | ------------- | ---------------------------------------- | --------- | --- | --------- | -------------------------- |
| 30000         | `0x7530`      | Assign Modbus Address (Button Triggered) | 10        | W   | 2× UINT16 | `0x55AA` + `[New Address]` |

**How to use Broadcast Address Assignment:**

1. The Host PLC sends a broadcast write command (Slave ID = `0`) to register `30000`.
2. The payload must be 2 words (4 bytes): `0x55AA` followed by the `[New Address]` (e.g., `0x0005`).
3. **Action:** Only the meter that currently has its **physical reset button pressed** will accept this command and update its address. All other meters on the bus will ignore it.

***

### 8. Ordering Information

<table><thead><tr><th width="75.7777099609375">#</th><th width="176.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SPM02-D2M1</td><td>SPM02 FLEX 63A/3PN  Modbus RTU</td></tr></tbody></table>

***

### 9. FAQ&#x20;

{% content-ref url="/pages/149DFxm5iomFCS9alhv5" %}
[FAQ](/faq/overview)
{% endcontent-ref %}

***

### 10. Troubleshooting

{% content-ref url="/pages/td5Nnli4rm9AAhvTaYLk" %}
[Troubleshooting](/troubleshooting/overview)
{% endcontent-ref %}

### 11. Printed Document

<table data-full-width="false"><thead><tr><th width="588.5555419921875">Document</th><th>Download</th></tr></thead><tbody><tr><td>Datasheet</td><td><a href="https://downloads.bituo-technik.com/Datasheet/SPM02R-FLEX-All_Datasheet_EN.pdf">⬇️ PDF</a></td></tr><tr><td>User Guide</td><td><a href="https://downloads.bituo-technik.com/User-Guide/SPM01R02R-All-in-One_User-Guide_ENCN.pdf">⬇️ PDF</a></td></tr></tbody></table>

### 12. Explore More

<br>


# SPM01R MCBM

{% hint style="info" %}
&#x20;**Applies to:** SPM01R MCBM | **Hardware Revision:** V1.0+ | **Last Updated:** 2026-07-18
{% endhint %}

### 1.  Introduction

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FNwfwEXKD1x1aYLbUYRlM%2FSPM01-MCBM-485-%E9%95%BF%E7%BA%BF%E5%9B%BE%E7%89%87%E6%AC%BE_2212.png?alt=media&amp;token=cfde8b70-b4c5-41a0-9bf6-bbb1281a1ef7" alt="" width="188"><figcaption></figcaption></figure></div>

Designed for direct mounting on miniature circuit breakers (MCBs), the SPM01R Miniature Energy Meter features robust Modbus RTU (RS485) communication. It delivers precise, real-time 1-phase energy data through a secure, reliable wired network.

#### Product Highlights

* **Space saving:** Designed for direct mounting on MCBs, it installs easily into distribution boards without occupying DIN-rail space, perfect for crowded panels.
* **Real-time Monitoring:** Measures voltage, current, power, power factor, and energy in real-time to help users optimize energy usage.
* **Large Aperture:** Supports cables up to 16mm² with a 9.6mm aperture, enabling measurement up to 63A.
* **Precise Measurement:** Delivers accurate active energy measurements with a tolerance of 1%, ensuring precise monitoring of energy consumption.
* **Isolated Connectivity:** Features a 4kV isolated Modbus RTU (RS485) interface for safe, stable, and interference-free integration into energy management systems.

#### Typical Applications

* Energy management systems (EMS) for buildings, Infrastructure, and Industry

### 2. Part Description

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FbVBDVGwHrmtDZVVuP74N%2Fimage.png?alt=media&amp;token=b4c1da56-3529-49a4-af8b-1a2b2af23023" alt="" width="303"><figcaption></figcaption></figure>

<table><thead><tr><th width="84.5555419921875">#</th><th width="279.3333740234375">Element</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>Terminal plate for L connection</td><td>Insert to protective device terminal box for power supply from Line<sup>1)</sup></td></tr><tr><td>2</td><td>Cable for Neutral (N) connection</td><td>Connect to power supply from Neutral</td></tr><tr><td>3</td><td>Through-hole for L wire</td><td>Through-hole for L wire: Ensure the wire(L) passes through the hole.</td></tr><tr><td>4</td><td>Reset button</td><td>Press and hold for above 5 seconds to reset communication settings to default.</td></tr><tr><td>5</td><td>LED indicator</td><td>Shows device operation and network status through different flashing patterns.<sup>2)</sup></td></tr><tr><td>6</td><td>Current flow direction</td><td>Indicates forward / positive power flow for installation</td></tr><tr><td>7</td><td>Product model</td><td>Refer to the 'Ordering Information' section for product selection.</td></tr><tr><td>8</td><td>RS485 communication wire</td><td>White wire: RS485-A
<br>Blue wire: RS485-B</td></tr></tbody></table>

Remark:

1\) The manufacturer has only verified the compatibility of SPM01R MCBM with Siemens 5SY/5SL series, including tests on wiring capacity, thermal performance, and mechanical fit etc. The flexible version is recommended if you are unsure about MCB-mounting compatibility with your circuit breakers.

2\) Refer to the user guide of your selected models for detailed LED status indicators.

### 3. Technical Data

| Parameter                                | Specification            |
| ---------------------------------------- | ------------------------ |
| Rated operating voltage *U*<sub>n</sub>  | 220-240 VAC, 50/60Hz     |
| Max monitoring current *I*<sub>max</sub> | 63 A                     |
| Over-voltage category                    | III                      |
| Rated insolating voltage *U*<sub>i</sub> | 250V                     |
| Rated impulse withstand voltage *U*imp   | 4kV                      |
| Pollution degree                         | 3                        |
| Protection degree                        | IP20                     |
| Energy measurement accuracy              | ±1%                      |
| Maximum power consumption                | ≤ 2VA                    |
| Rated operating temperature              | -25°C to 55°C            |
| Size: Height x Width x Depth             | 46.8mm x 17.8mm x 21.3mm |
| Integrated communication option          | Modbus RTU (RS485)       |

### 4. Mechanical Outline

**Dimension:** Unit in mm

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2F9K3acjirQZR7t8U86HnM%2Fimage.png?alt=media&amp;token=b46b49ab-b869-4e2a-bc1a-d40b17ca2165" alt="" width="488"><figcaption></figcaption></figure>

### 5. Electrical Installation&#x20;

#### Wiring Diagram

**⚠️ Safety Remarks:**

* The device must be associated with easily accessible upstream protective devices ‒ such as miniature circuit breakers (MCB).
* The device must be installed, operated, serviced, and maintained **ONLY** by qualified professionals.
* Please read the user guide carefully before installation for detailed wiring diagrams and safety precautions.
* The manufacturer has only verified the compatibility of SPM01 MCBM with Siemens 5SY/5SL series, including tests on wiring capacity, thermal performance, and mechanical fit etc. The flexible version is recommended if you are unsure about MCB-mounting compatibility with your circuit breakers.

The device comes with 400mm twisted white (RS485-A) and blue (RS485-B) wires. For long-distance RS485 communication, it is recommended to trim these wires short and splice them to a standard shielded twisted-pair cable.

<br>

{% columns %}
{% column %}

<p align="center"><strong>Downstream Installation</strong></p>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FTCRphJlIlJ1GT0MQrj75%2Fimage.png?alt=media&amp;token=a2101861-1a77-4564-b640-b57197ae0b88" alt=""><figcaption></figcaption></figure>
{% endcolumn %}

{% column %}

<p align="center"><strong>Upstream Installation</strong></p>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKdhqWA4kGHuH2ulsAqRG%2Fimage.png?alt=media&amp;token=75cdf6c2-2dbb-4e86-8484-e73e0a3cc1da" alt=""><figcaption></figcaption></figure>
{% endcolumn %}
{% endcolumns %}

Forward Energy Calculation: The energy flowing in the same direction as the energy flow arrow printed on the sensor housing is counted as forward energy.

#### Installation Video

*🚧Coming soon...*

### 6. User Interface

#### Reset Button

Press and hold for above 5 seconds to reset communication settings to the following factory default:

* **Modbus Address:** 247
* **Baud Rate:** 9600 bps
* **Data Format:** N, 8, 1 (No parity, 8 data bits, 1 stop bit)

#### LED Indicator

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Flashing at 1Hz</strong></td><td>Data transmitting - Flashes 3 times per exchange. Flashes continuously if polling interval is &#x3C;3s.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>Standby (No data exchange)</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr></tbody></table>

***

### 7. System Integration

The Modbus RTU (RS485) version utilizes a standard, open industrial communication protocol. It can be directly integrated into a wide range of third-party systems, including PLCs, edge gateways, data loggers, SCADA, and Building Management Systems (BMS). Unlike cloud-dependent versions, it operates entirely locally and requires a wired connection to a Modbus master device to poll and collect data. For register maps and communication parameters, please refer to the provided Modbus protocol documentation.

**Device Commissioning**

To integrate the meter into your RS485 network, you can configure the Modbus address using one of the following two methods:

**Method 1: Point-to-Point Configuration (Default Settings)** Connect a single device to your master device and configure it using the factory default settings (Modbus Address: `247`, Baud Rate: `9600 bps`, `N, 8, 1`). You can reset the device to these defaults at any time by pressing and holding the Reset button for over 5 seconds.

**Method 2: Broadcast Address Assignment (Button Triggered)** This feature allows for quick commissioning of multiple devices on the same bus without needing to wire and configure them one by one.

Send this command to **Broadcast Address `0`**:

| Address (DEC) | Address (HEX) | Description                              | Func Code | R/W | Data Type | Write Value                |
| ------------- | ------------- | ---------------------------------------- | --------- | --- | --------- | -------------------------- |
| 30000         | `0x7530`      | Assign Modbus Address (Button Triggered) | 10        | W   | 2× UINT16 | `0x55AA` + `[New Address]` |

**How to use Broadcast Address Assignment:**

1. The Host PLC sends a broadcast write command (Slave ID = `0`) to register `30000`.
2. The payload must be 2 words (4 bytes): `0x55AA` followed by the `[New Address]` (e.g., `0x0005`).
3. **Action:** Only the meter that currently has its **physical reset button pressed** will accept this command and update its address. All other meters on the bus will ignore it.

***

### 8. Ordering Information

<table><thead><tr><th width="75.7777099609375">#</th><th width="176.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SPM01-D1M1</td><td>SPM01 MCBM-DI 63A/1PN  Modbus RTU</td></tr><tr><td>2</td><td>SPM01-U1M1</td><td>SPM01 MCBM-UI 63A/1PN  Modbus RTU</td></tr></tbody></table>

***

### 9. FAQ&#x20;

{% content-ref url="/pages/149DFxm5iomFCS9alhv5" %}
[FAQ](/faq/overview)
{% endcontent-ref %}

***

### 10. Troubleshooting

{% content-ref url="/pages/td5Nnli4rm9AAhvTaYLk" %}
[Troubleshooting](/troubleshooting/overview)
{% endcontent-ref %}

### 11. Printed Document

<table data-full-width="false"><thead><tr><th width="588.5555419921875">Document</th><th>Download</th></tr></thead><tbody><tr><td>Datasheet</td><td><a href="https://downloads.bituo-technik.com/Datasheet/SPM01R-MCBM-All_Datasheet_EN.pdf">⬇️ PDF</a></td></tr><tr><td>User Guide</td><td><a href="https://downloads.bituo-technik.com/User-Guide/SPM01R02R-All-in-One_User-Guide_ENCN.pdf">⬇️ PDF</a></td></tr></tbody></table>

### 12. Explore More

<br>


# SPM02R MCBM

{% hint style="info" %}
&#x20;**Applies to:** SPM02R MCBM | **Hardware Revision:** V3.0+ | **Last Updated:** 2026-07-18
{% endhint %}

### 1.  Introduction

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FM6XyMphAulvpvx0mTTcR%2Fimage.png?alt=media&amp;token=c00759a5-9657-4165-aafb-49b824cf9353" alt="" width="188"><figcaption></figcaption></figure></div>

Built for seamless MCB integration, the **SPM02R Miniature Energy Meter** is an advanced 3-phase monitoring device. Equipped with a reliable Modbus RTU (RS485) interface, it guarantees stable, accurate data acquisition via a robust wired connection.

#### Product Highlights

* **Ultra-Compact Installation:** Mounts directly on MCBs without consuming DIN-rail space, optimizing layout for crowded panels.
* **Real-Time Power Tracking:** Instantly captures voltage, current, power, and energy metrics for full visibility into 3-phase networks.
* **Built for Heavy Loads:** Features a 9.6mm aperture accepting up to 16mm² wiring, reliably supporting up to 63A per phase.
* **Uncompromising Precision:** Delivers accurate active energy measurements with a 1% tolerance for precise 3-phase monitoring.
* **Isolated RS485 Connectivity:** Features a 4kV isolated Modbus RTU interface for safe, interference-free integration into PLCs, SCADA, and BMS.

#### Typical Applications

* Energy management systems (EMS) for buildings, Infrastructure, and Industry

### 2. Part Description

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FP8E336410ApT9ws9e0HA%2Fimage.png?alt=media&amp;token=41becc8d-e84e-4aa8-8b58-5ba1f29c51c7" alt="" width="348"><figcaption></figcaption></figure>

<table><thead><tr><th width="84.5555419921875">#</th><th width="279.3333740234375">Element</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>Terminal plate for X connection</td><td>Insert to protective device terminal box for power supply from phase<sup>1)</sup></td></tr><tr><td>2</td><td>Terminal plate for Y connection</td><td>Insert to protective device terminal box for power supply from phase<sup>1)</sup></td></tr><tr><td>3</td><td>Terminal plate for Z connection</td><td>Insert to protective device terminal box for power supply from phase<sup>1)</sup></td></tr><tr><td>4</td><td>Cable for N connection</td><td>Connect to power supply from Neutral (N)</td></tr><tr><td>5</td><td>Through-hole for X wire</td><td>Through-hole for X wire: Ensure the wire (X) passes through the hole.</td></tr><tr><td>6</td><td>Through-hole for Y wire</td><td>Through-hole for Y wire: Ensure the wire (Y) passes through the hole.</td></tr><tr><td>7</td><td>Through-hole for Z wire</td><td>Through-hole for Z wire: Ensure the wire (Z) passes through the hole.</td></tr><tr><td>8</td><td>Reset button</td><td>Press and hold for above 5 seconds to reset communication settings to default.</td></tr><tr><td>9</td><td>LED indicator</td><td>Shows device operation and network status through different flashing patterns.<sup>2)</sup></td></tr><tr><td>10</td><td>Power flow direction</td><td>Indicates forward / positive power flow for installation</td></tr><tr><td>11</td><td>Product model</td><td>Refer to the 'Ordering Information' section for product selection.</td></tr><tr><td>12</td><td>RS485 communication wire</td><td>White wire: RS485-A
<br>Blue wire: RS485-B</td></tr></tbody></table>

Remark:

1\) The manufacturer has only verified the compatibility of SPM02 MCBM with Siemens 5SY/5SL series, including tests on wiring capacity, thermal performance, and mechanical fit etc. The flexible version is recommended if you are unsure about MCB-mounting compatibility with your circuit breakers.

2\) Refer to the user guide of your selected models for detailed LED status indicators.

### 3. Technical Data

| Parameter                                | Specification                                                      |
| ---------------------------------------- | ------------------------------------------------------------------ |
| Rated operating voltage *U*<sub>n</sub>  | <p>220-240 VAC (L-N), 50/60 Hz <br>380-415 VAC (L-L), 50/60 Hz</p> |
| Max monitoring current *I*<sub>max</sub> | 63 A                                                               |
| Over-voltage category                    | III                                                                |
| Rated insolating voltage *U*<sub>i</sub> | 440V                                                               |
| Rated impulse withstand voltage *U*imp   | 4kV                                                                |
| Pollution degree                         | 3                                                                  |
| Protection degree                        | IP20                                                               |
| Energy measurement accuracy              | ±1%                                                                |
| Maximum Power consumption                | ≤ 2VA                                                              |
| Rated operating temperature              | -25°C to 55°C                                                      |
| Size: Height x Width x Depth             | 46.4x53.0x21.3mm                                                   |
| Integrated communication option          | Modbus RTU (RS485)                                                 |

### 4. Mechanical Outline

**Dimension:** Unit in mm

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FbVqbak0zACrWZRHRy4ew%2Fimage.png?alt=media&amp;token=cdbed77d-61e3-465c-b215-42d1420d3fa9" alt="" width="557"><figcaption></figcaption></figure>

### 5. Electrical Installation&#x20;

#### Wiring Diagram

**⚠️ Safety Remarks:**

* The device must be associated with easily accessible upstream protective devices ‒ such as miniature circuit breakers (MCB).
* The device must be installed, operated, serviced, and maintained **ONLY** by qualified professionals.
* Please read the user guide carefully before installation for detailed wiring diagrams and safety precautions.
* The manufacturer has only verified the compatibility of SPM02 MCBM with Siemens 5SY/5SL series, including tests on wiring capacity, thermal performance, and mechanical fit etc. The flexible version is recommended if you are unsure about MCB-mounting compatibility with your circuit breakers.

The device comes with 400mm twisted white (RS485-A) and blue (RS485-B) wires. For long-distance RS485 communication, it is recommended to trim these wires short and splice them to a standard shielded twisted-pair cable.

{% columns %}
{% column width="50%" %}

<p align="center"><strong>Downstream Installation</strong></p>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2F8EUVQdV7dVrzzOkZe69S%2Fimage.png?alt=media&amp;token=e9bc554e-6d6e-4b59-9935-516b0821450d" alt=""><figcaption></figcaption></figure>
{% endcolumn %}

{% column width="50%" %}

<p align="center"><strong>Upstream Installation</strong></p>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fi84EYxqOlilhI5gWeftC%2Fimage.png?alt=media&amp;token=46869ff1-3b14-4bd0-9117-0dc8fed5ad37" alt=""><figcaption></figcaption></figure>
{% endcolumn %}
{% endcolumns %}

*Forward Energy Calculation: The energy flowing in the same direction as the energy flow arrow printed on the sensor housing is counted as forward energy.*

#### Installation Video

*🚧Coming soon...*

### 6. User Interface

#### Reset Button

Press and hold for above 5 seconds to reset communication settings to the following factory default:

* **Modbus Address:** 247
* **Baud Rate:** 9600 bps
* **Data Format:** N, 8, 1 (No parity, 8 data bits, 1 stop bit)

#### LED Indicator

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Flashing at 1Hz</strong></td><td>Data transmitting - Flashes 3 times per exchange. Flashes continuously if polling interval is &#x3C;3s.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>Standby (No data exchange)</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Fault Alarm - Fault detected. Please check wiring and power supply.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fgjz0xceslVOF4qKWMqa0%2FRed-Flashing-at-1Hz.jpg?alt=media&amp;token=202171d9-496d-4264-9b50-a7ab0d175d0c">Red-Flashing-at-1Hz.jpg</a></td></tr></tbody></table>

***

### 7. System Integration

The Modbus RTU (RS485) version utilizes a standard, open industrial communication protocol. It can be directly integrated into a wide range of third-party systems, including PLCs, edge gateways, data loggers, SCADA, and Building Management Systems (BMS). Unlike cloud-dependent versions, it operates entirely locally and requires a wired connection to a Modbus master device to poll and collect data. For register maps and communication parameters, please refer to the provided Modbus protocol documentation.

**Device Commissioning**

To integrate the meter into your RS485 network, you can configure the Modbus address using one of the following two methods:

**Method 1: Point-to-Point Configuration (Default Settings)** Connect a single device to your master device and configure it using the factory default settings (Modbus Address: `247`, Baud Rate: `9600 bps`, `N, 8, 1`). You can reset the device to these defaults at any time by pressing and holding the Reset button for over 5 seconds.

**Method 2: Broadcast Address Assignment (Button Triggered)** This feature allows for quick commissioning of multiple devices on the same bus without needing to wire and configure them one by one.

Send this command to **Broadcast Address `0`**:

| Address (DEC) | Address (HEX) | Description                              | Func Code | R/W | Data Type | Write Value                |
| ------------- | ------------- | ---------------------------------------- | --------- | --- | --------- | -------------------------- |
| 30000         | `0x7530`      | Assign Modbus Address (Button Triggered) | 10        | W   | 2× UINT16 | `0x55AA` + `[New Address]` |

**How to use Broadcast Address Assignment:**

1. The Host PLC sends a broadcast write command (Slave ID = `0`) to register `30000`.
2. The payload must be 2 words (4 bytes): `0x55AA` followed by the `[New Address]` (e.g., `0x0005`).
3. **Action:** Only the meter that currently has its **physical reset button pressed** will accept this command and update its address. All other meters on the bus will ignore it.

### 8. Ordering Information

<table><thead><tr><th width="75.7777099609375">#</th><th width="176.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SPM02-D1M1</td><td>SPM02 MCBM-DI 63A/3PN  Modbus RTU</td></tr><tr><td>2</td><td>SPM02-U1M1</td><td>SPM02 MCBM-UI 63A/3PN  Modbus RTU</td></tr></tbody></table>

### 9. FAQ&#x20;

{% content-ref url="/pages/149DFxm5iomFCS9alhv5" %}
[FAQ](/faq/overview)
{% endcontent-ref %}

***

### 10. Troubleshooting

{% content-ref url="/pages/td5Nnli4rm9AAhvTaYLk" %}
[Troubleshooting](/troubleshooting/overview)
{% endcontent-ref %}

### 11. Printed Document

<table data-full-width="false"><thead><tr><th width="588.5555419921875">Document</th><th>Download</th></tr></thead><tbody><tr><td>Datasheet</td><td><a href="https://downloads.bituo-technik.com/Datasheet/SPM02R-MCBM-All_Datasheet_EN.pdf">⬇️ PDF</a></td></tr><tr><td>User Guide</td><td><a href="https://downloads.bituo-technik.com/User-Guide/SPM01R02R-All-in-One_User-Guide_ENCN.pdf">⬇️ PDF</a></td></tr></tbody></table>

### 12. Explore More


# SDM Series

## SDM Series — Compact Energy Meters with Clamp CTs

Future-ready smart energy meters with split-core clamp CTs, designed for DIN rail installation. Supports three-phase, split-phase, and multi-branch single-phase monitoring — engineered for both IEC and UL markets.

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fazc1ZJIySptoUxzRFM9K%2Fimgi_9_SDM-Family_3%20(1).webp?alt=media&amp;token=fd9fe6e1-4c29-4a49-829f-b8d4376402c8" alt=""><figcaption></figcaption></figure>

***

### Product Variants

SDM products are defined across **three dimensions**:

#### 1. Product Platform

|                            | **SDM01 Combo**                                 | **SDM02 SP**                          |
| -------------------------- | ----------------------------------------------- | ------------------------------------- |
| **Target System**          | Three-phase (3P4W) or multi-branch single-phase | Split-phase / two-phase               |
| **Market**                 | IEC (EU, Asia, etc.)                            | IEC + UL (North America)              |
| **Rated Voltage**          | 220–240 VAC (L-N) / 380–415 VAC (L-L)           | 110–240 VAC (L-N) / 220–240 VAC (L-L) |
| **No. of CTs**             | 3× split-core CTs                               | 2× split-core CTs                     |
| **Dimension**              | 113.7 × 18.0 × 65.9 mm (1MW DIN rail)           | 42.2 × 41.6 × 20 mm                   |
| **Wired Communication**    | RS485 (Modbus RTU)                              | —                                     |
| **Active Energy Accuracy** | Class 1 (IEC 61557-12)                          | Class 1 (IEC 61557-12)                |

#### 2. CT Current Rating

| CT Rating         | Aperture | SDM01 Combo | SDM02 SP          |
| ----------------- | -------- | ----------- | ----------------- |
| **120A**          | Ø16 mm   | ✅           | ✅                 |
| **200A**          | Ø20 mm   | ✅           | ✅                 |
| **100A (UL2808)** | Ø12 mm   | —           | ✅ (North America) |

> 💡 The CT is factory-calibrated together with the main module. Always order the CT rating that matches your installation — CTs are **not interchangeable** between ratings.

> ℹ️ Current monitoring can be extended up to **400A** via custom CT configurations. Please contact us for customization inquiries.

#### 3. Connectivity

**Wireless** — select one firmware variant per order:

<table><thead><tr><th width="116">Variant</th><th width="137">Communication</th><th width="235">Archetecture</th><th>API Style</th><th width="140">Typical Users</th></tr></thead><tbody><tr><td><strong>Tuya Wi-Fi</strong> (<code>*TW</code>)</td><td>Wi-Fi</td><td>BK7231N SoC (Tuya Firmware, Slave) + Metering MCU (Bituo Firmware, Master)</td><td>MQTT(Tuya Proprietary)</td><td>Tuya ecosystem, IoT beginners</td></tr><tr><td><strong>Tuya Zigbee</strong> (<code>*TZ</code>)</td><td>Zigbee</td><td>EFR32MG21 SoC (Tuya Firmware, Slave) + Metering MCU (Bituo Firmware, Master)</td><td>Tuya Proprietary Clusters</td><td>Tuya ecosystem with Zigbee hub</td></tr><tr><td><strong>Open Wi-Fi</strong> (<code>*EW</code>)</td><td>BLE + Wi-Fi</td><td>ESP8685 SoC (Bituo Firmware, Master) + Metering MCU (Bituo Firmware, Slave)</td><td>MQTT, HTTP, UDP, BLE</td><td>DIYers, System Integrators</td></tr><tr><td><strong>Std. Zigbee</strong> (<code>*TZ-U01</code>)</td><td>Zigbee 3.0</td><td>EFR32MG21 SoC (Bituo Firmware, Master) + Metering MCU (Bituo Firmware, Slave)</td><td>Standard Zigbee 3.0 Clusters</td><td>System Integrators, DIYers</td></tr></tbody></table>

**Wired** — availability by platform:

|                        | **SDM01 Combo**            | **SDM02 SP** |
| ---------------------- | -------------------------- | ------------ |
| **RS485 (Modbus RTU)** | ✅ Included in all variants | —            |

> ℹ️ On SDM01 Combo, RS485 is always present alongside the wireless module — it is not a separate variant choice.

***

### Sub Pages

<table><thead><tr><th width="194">Model</th><th>Description</th></tr></thead><tbody><tr><td><a data-mention href="/product-document/sdm-series/sdm01-combo">SDM01 Combo</a></td><td>3PN / Multi-branch 1P, 120A or 200A</td></tr><tr><td><a data-mention href="/product-document/sdm-series/sdm02-sp">SDM02 SP</a></td><td>Split-phase / 2×1P+N, 120A / 200A / 100A (UL)</td></tr></tbody></table>

***

### Related

[SPM/SDM Zigbee Cluster Reference](/device-api/spm-sdm-zigbee-cluster-reference)

[SDM01 Modbus RTU Map](/device-api/sdm01-modbus-rtu-map)


# SDM01 Combo

{% hint style="info" %}
&#x20;**Applies to:** SDM01 Combo | **Hardware Revision:** V1.0+ | **Last Updated:** 2026-05-13
{% endhint %}

### 1.  Introduction

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fo7qnKAJZDwtLwjOCc1VV%2Fimage.png?alt=media&amp;token=6cf775e4-e1aa-4418-8767-49e5b19834c6" alt=""><figcaption></figcaption></figure></div>

The **SDM01 Combo Compact Energy Meter** is a compact 18mm-wide DIN-rail device for real-time three-phase and multi-branch single-phase monitoring. With three split-core CTs, it precisely measures voltage, current, power, and energy, supporting wired and wireless communication for seamless integration.

#### Product Highlights

* **Bi-directional Measurement**: Measure power and energy flow in both consumption and generation.
* **Easy Installation**: The monitoring module requires just 1MW at DIN rail, paired with compact split-core CTs.
* **Local Automation**: Enable a wide range of local APIs, ideal for DLB and zero export for Home Energy Management Systems (HEMS).
* **Real-time Monitoring**: Monitor key electrical data like Voltage, Current, and Power in real time.
* **Versatile Connectivity**: Choose from various communication options such as Wi-Fi, Zigbee, Modbus, etc., catering to diverse system integration needs.
* **Modbus Support**: Modbus version & hybrid WiFi/Zigbee+Modbus variants are available for industrial installations.

#### Typical Application

* Home energy management systems (HEMS)
* energy management systems (EMS) for small business&#x20;
* Energy management systems (EMS) for buildings, Infrastructure, and Industry
* Dynamic load balancing (DLB) for electrical vehicle charging
* Export limitation for renewable power generation

***

### 2. Part Description

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FEEM8PbtS9IH2xcHZXvb7%2Fimage.png?alt=media&amp;token=417eed31-37a5-4702-8d94-df1f80bb05d6" alt=""><figcaption></figcaption></figure>

<table data-header-hidden><thead><tr><th width="84.5555419921875">#</th><th width="257.666748046875">Element</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>Connector for voltage take-offs connection</td><td>The monitor is powered by AC power supply and measures voltage through four cables: X, Y, Z, and N</td></tr><tr><td>2</td><td>Connector for current transformer connection</td><td>The Red (+) and Black (-) wires of CT(X), CT(Y), and CT(Z) must match the corresponding polarity of the connector.</td></tr><tr><td>3</td><td>Connector for RS485 communication</td><td>For Modbus RTU communication</td></tr><tr><td>4</td><td>Reset button</td><td>Press and hold for 3–5 seconds to enter pairing mode.</td></tr><tr><td>5</td><td>Status LED (ACT)</td><td>Indicates device operation and network status through different flashing patterns.</td></tr><tr><td>6</td><td>Alarm LED (AL)</td><td>Flashes to indicate system alarms or errors.</td></tr><tr><td>7</td><td>Product QR code</td><td>Contains manufacturing batch information.</td></tr><tr><td>8</td><td>Product model</td><td>See “Ordering Information” section for product selection</td></tr><tr><td>9</td><td>Locking clip for DIN rail mounting</td><td>Mounts onto a 35mm DIN rail.</td></tr><tr><td>10</td><td>Calibration ID </td><td>The calibration ID on the split-core CT must match the one on the monitor for optimal accuracy.</td></tr><tr><td>11</td><td>Split-core CT locking clasp</td><td>Ensure the clasp is securely locked for precise measurement.</td></tr><tr><td>12</td><td>Positive power flow direction</td><td>Indicates positive power flow direction for CT(X), CT(Y), and CT(Z) installation.</td></tr></tbody></table>

***

### 3. Technical Data

<table data-header-hidden><thead><tr><th width="342"></th><th></th></tr></thead><tbody><tr><td>Rated operating voltage <em>U</em><sub>n</sub></td><td>~220-240 VAC phase to neutral, 50/60 Hz<br>~380-415 VAC phase to phase, 50/60 Hz<sup>1)</sup></td></tr><tr><td>Max current <em>I</em><sub>max</sub></td><td>120A / 200A</td></tr><tr><td>Over-voltage category</td><td>III</td></tr><tr><td>Rated insolating voltage <em>U</em><sub>i</sub></td><td>440V</td></tr><tr><td>Rated impulse withstand voltage <em>U</em>imp</td><td>4kV</td></tr><tr><td>Pollution degree</td><td>3</td></tr><tr><td>Protection degree</td><td>IP20</td></tr><tr><td>Energy measurement accuracy</td><td>Class 1 (IEC 61557-12)</td></tr><tr><td>Maximum Power consumption</td><td>≤ 2VA</td></tr><tr><td>Rated operating temperature</td><td>-25℃ to 55℃</td></tr><tr><td>Main module dimension</td><td>113.7×18.0×65.9mm</td></tr><tr><td>Clamp CT apertures</td><td>Ø16mm / Ø20mm</td></tr><tr><td>Communication Type</td><td>Wireless<sup>2)</sup>: BLE; Wi-Fi; Zigbee<br>Wired: RS485</td></tr></tbody></table>

**Remark:**\
1\) Not suitable for 3P3W installation.

2\) Four variants of main module available with different connectivity - Tuya WiFI (SDM01-TWM-\*), Tuya Zigbee (SDM01-TZM-\*), Open WiFI (SDM01-EWM-\*), Standard Zigbee 3.0 (SDM01-TZM-\*-U01)

***

### 4. Mechanical Outline

* **Dimension:** Unit in mm
* **Main Unit:** Monitoring module for DIN-rail installation (18mm width)

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FsVVBSHX2do6iPz82QDpP%2Fimage.png?alt=media&amp;token=b979d225-7bd5-4712-b600-495f8acf9b2e" alt=""><figcaption></figcaption></figure>

* **Split-core Current Transformer - 120A (CT Clamp - 120A):**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FEMNc27n6KlpdLzKVdJtD%2Fimage.png?alt=media&amp;token=56f51d22-7def-4630-983c-ef826897791a" alt=""><figcaption></figcaption></figure>

* **Split-core Current Transformer - 200A (CT Clamp - 200A):**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FnSdF3ymrj0Tw5NFLOgEF%2Fimage.png?alt=media&amp;token=d2edbc09-3b1a-44d7-848c-8a14a5a776a3" alt=""><figcaption></figcaption></figure>

***

### 5. Electrical Installation&#x20;

#### Wiring Diagram

**⚠️ Safety Remarks:**

* The device must be associated with easily accessible upstream protective devices ‒ such as miniature circuit breakers (MCB).
* The device must be installed, operated, serviced, and maintained **ONLY** by qualified professionals.
* Please read the user guide carefully before installation for detailed wiring diagrams and safety precautions.

<p align="center"><strong>Three-phase (3P4W) System Wiring</strong></p>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FQZC5leYK1eTYjyMd5mWz%2FSDM01-3PN-Wiring_EN.png?alt=media&amp;token=7f992b81-c923-474c-a3e6-407426efa981" alt=""><figcaption></figcaption></figure>

<p align="center"><strong>Single-phase System Wiring up to 3 Branch Circuits</strong> </p>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fg8g6kBoS52e5zc6A47gU%2FSDM01-3x1PN-Wiring_EN.png?alt=media&amp;token=7a997d8f-fb4b-497a-8c0c-88d2d4e8e7fb" alt=""><figcaption></figcaption></figure>

<p align="center"></p>

**Note:** Naming conventions for three-phase systems vary by region (e.g., L1, L2, L3 in Europe vs. A, B, C in China). Additionally, this product supports monitoring three independent branch circuits in a single-phase system. Therefore, the terminals are universally labeled as **Lx, Ly, and Lz**.

#### Installation Video

{% embed url="<https://youtu.be/t6z_me6g-GM>" %}

***

### 6. User Interface

#### Reset Button

Press and hold for 3–5 seconds to enter pairing mode.

#### LED Indicator

{% tabs %}
{% tab title="Tuya WiFi " %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Device connected - the device is online and functioning normally with cloud connectivity.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect using saved network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Network connected, cloud unreachable - the device is connected to Wi-Fi/Zigbee, but failed to reach the cloud.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Alarm reminder -<br>The device has detected a fault. Please check the wiring and power supply.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fgjz0xceslVOF4qKWMqa0%2FRed-Flashing-at-1Hz.jpg?alt=media&amp;token=202171d9-496d-4264-9b50-a7ab0d175d0c">Red-Flashing-at-1Hz.jpg</a></td></tr></tbody></table>
{% endtab %}

{% tab title="Tuya Zigbee" %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Device connected - the device is online and functioning normally with cloud connectivity.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect using saved network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Network connected, cloud unreachable - the device is connected to Wi-Fi/Zigbee, but failed to reach the cloud.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Alarm reminder -<br>The device has detected a fault. Please check the wiring and power supply.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fgjz0xceslVOF4qKWMqa0%2FRed-Flashing-at-1Hz.jpg?alt=media&amp;token=202171d9-496d-4264-9b50-a7ab0d175d0c">Red-Flashing-at-1Hz.jpg</a></td></tr></tbody></table>
{% endtab %}

{% tab title="Standard Zigbee 3.0" %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Zigbee connected, BLE disconnected – the device is connected to a Zigbee network while BLE is turned off or not connected.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect both BLE (if available) and Zigbee using saved settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>BLE connected(if available)  - the LED flashes at 1Hz whenever BLE is connected, regardless of Zigbee status.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>The device has detected a fault. Please check the wiring and power supply.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fgjz0xceslVOF4qKWMqa0%2FRed-Flashing-at-1Hz.jpg?alt=media&amp;token=202171d9-496d-4264-9b50-a7ab0d175d0c">Red-Flashing-at-1Hz.jpg</a></td></tr></tbody></table>
{% endtab %}

{% tab title="Open WiFi" %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Wi-Fi connected, BLE disconnected - the device is connected to Wi-Fi while BLE is disconnected.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect both BLE and Wi-Fi using saved settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>BLE connected - the LED flashes at 1Hz whenever BLE is connected, regardless of Wi-Fi status.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Alarm reminder -<br>The device has detected a fault. Please check the wiring and power supply.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fgjz0xceslVOF4qKWMqa0%2FRed-Flashing-at-1Hz.jpg?alt=media&amp;token=202171d9-496d-4264-9b50-a7ab0d175d0c">Red-Flashing-at-1Hz.jpg</a></td></tr></tbody></table>
{% endtab %}
{% endtabs %}

***

### 7. System Integration

#### Wireless communication

Products equipped with different communication SoC firmwares connect to different systems and cloud platforms. Users can select the appropriate version based on their specific application requirements.

{% tabs %}
{% tab title="Tuya WiFi " %}
The Tuya WiFi version can only be integrated into the Tuya Cloud using Tuya's encrypted MQTT communication. It cannot be directly integrated with any third-party cloud platforms, ecosystems, or gateways. Third-party clouds or edge gateways need to be integrated via Tuya cloud APIs. For details, please refer to Tuya's developer documentation.

**Note:**&#x20;

1. Tuya's strategy for adjusting the cloud data reporting frequency is not fully disclosed. Based on the latest updates as of April 2026, provided the daily data reporting traffic limit is not exceeded, the fastest expected reporting interval will be between 5 to 15 minutes.
2. Tuya's Smart Life App is user-friendly and straightforward, making it ideal for entry-level smart home users who prefer simplicity and basic energy consumption monitoring.
   {% endtab %}

{% tab title="Tuya Zigbee" %}
For standard operation, the Tuya Zigbee version must be integrated with a Tuya gateway, which then connects to the Tuya Cloud via Tuya's encrypted MQTT communication.

**Note:**&#x20;

1. Tuya's strategy for adjusting the cloud data reporting frequency is not fully disclosed. Based on the latest updates as of April 2026, provided the daily data reporting traffic limit is not exceeded, the fastest expected reporting interval will be between 5 to 15 minutes.
2. There are unofficial methods available on the market to integrate Tuya Zigbee products with third-party gateways or hubs - such as Home Assistant integration via Zigbee2MQTT. However, please be aware of the following potential issues when using these unofficial integration methods:

* **⚠️Network Congestion:** Tuya's proprietary Zigbee data transmission strategy does not bundle data packets. Consequently, high-frequency reporting of the extensive electrical data types from several energy meters, which generate significantly more data than typical smart home Zigbee devices, can easily cause Zigbee network congestion.
* **⚠️Security Risks:** Integrating with third-party Zigbee gateways using the default global Trust Centre Link Key “*ZigbeeAlliance09*” poses potential information security risks. Therefore, using non-Tuya gateways in commercial projects is highly discouraged. For third-party gateway integration, the **Standard Zigbee 3.0** version with Install Code is strongly recommended.
  {% endtab %}

{% tab title="Standard Zigbee 3.0" %}
The Standard Zigbee 3.0 version can seamlessly connects to third-party gateways. Thanks to the standardized application-layer integration of Zigbee 3.0, it is highly convenient and widely applicable for both residential and commercial building projects.

Currently supported smart home ecosystems include:

* **Home Assistant:** Integration via Zigbee2MQTT ([SPM01](https://www.zigbee2mqtt.io/devices/SPM02-U01.html#bituo-technik-spm02-u01), [SPM02](https://www.zigbee2mqtt.io/devices/SPM02-U01.html#bituo-technik-spm02-u01), [SDM01](https://www.zigbee2mqtt.io/devices/SDM01W-U01.html#bituo-technik-sdm01w-u01), and [SDM02](https://www.zigbee2mqtt.io/devices/SDM02-U01.html#bituo-technik-sdm02-u01))
* **SmartThings:** Integration via the SmartThings Hub driver (officially approved).
* **Homey:** Integration via the [Bituo Technik App ](https://homey.app/en-us/app/com.bituotechnik.iot/BITUO-TECHNIK/)

**You can find information about the commonly used Zigbee Cluster Library on** [**this page**](https://bituo-technik.gitbook.io/hc/device-api/zigbee/spm-sdm-zigbee-profile)**.**
{% endtab %}

{% tab title="Open WiFi" %}
The Open Wi-Fi version of SDM01 provides the following open APIs (refer to the Device API document), enabling users to implement local automation and connect to custom cloud platforms.

1. **Zero-Configuration Discovery Mechanism (LAN Addressing)**
   * **mDNS / DNS-SD:** Supports automatic discovery of the energy meter by EV chargers and PV inverters on the Local Area Network (LAN) without the need for IP scanning.
2. **BLE Near-Field Communication Mode (Offline/Maintenance)**
   * **BLE GATT (Time-limited activation):** Requires PIN code + PAKE algorithm authentication for local high-privilege configuration and network resets. Wakes up on demand and closes upon timeout.
   * **BLE Broadcast (Always-on 24/7):** Unidirectional broadcast of AES-encrypted real-time power data, allowing nearby low-power devices to listen with zero latency and without requiring a connection.
3. **LAN Standard Mode (Ultra-low Latency Device Communication)** *Plaintext or lightweight encryption for local networks.*
   * **Modbus TCP:** Used for local linkage with EV chargers and PV inverters.
   * **Local MQTT:** Used for local integration with open-source smart home ecosystems.
   * **WebSocket (WS) / Raw UDP:** Ultra-high frequency real-time power streaming subscription (enables DLB completion within 1-2 seconds).
   * **HTTP / CoAP:** Suitable for low-frequency parameter configuration and status queries.
4. **Cloud Device Access Layer (Device-to-Cloud / Southbound API)**
   * **MQTTS (MQTT over TLS 1.2/1.3):** Core main communication link.
   * **HTTPS (OTA dedicated):** Exclusively used for downloading large Over-The-Air (OTA) firmware upgrade packages.
     {% endtab %}
     {% endtabs %}

#### Wired communication

SDM01 provides a Modbus RTU over RS485 interface, making it convenient to use as a wired Modbus RTU meter. You can view the Modbus RTU register address information by clicking the page below.

{% content-ref url="/pages/cIwsN5OFt26gvjZMt9c1" %}
[SDM01 Modbus RTU Map](/device-api/sdm01-modbus-rtu-map)
{% endcontent-ref %}

***

### 8. Ordering Information

{% tabs %}
{% tab title="Tuya Wi-Fi" %}

<table><thead><tr><th width="75.7777099609375">#</th><th width="176.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SDM01-TWM-12</td><td>SDM01 SCTA-3×120A/Φ16 Wi-Fi (Tuya)+RS485</td></tr><tr><td>2</td><td>SDM01-TWM-20</td><td>SDM01 SCTA-3×200A/Φ20 Wi-Fi (Tuya)+RS485</td></tr><tr><td>3</td><td>SDM01-TWM-12TS</td><td>SDM01 SCTA-3×120A/Φ16 Wi-Fi (Tuya LAN+)+RS485</td></tr><tr><td>4</td><td>SDM01-TWM-20TS</td><td>SDM01 SCTA-3×200A/Φ20 Wi-Fi (Tuya LAN+)+RS485</td></tr></tbody></table>

1\) Tuya LAN+: Tuya LAN+ is a specific Wi-Fi SoC firmware provided by Tuya Smart that features local area network (LAN) communication. It is suitable for local LAN communication with products such as EV chargers, microinverters, and micro-energy storage systems that are also equipped with Tuya LAN+ communication firmware. This model can only be purchased through Tuya's official or designated channels.
{% endtab %}

{% tab title="Tuya Zigbee" %}

<table><thead><tr><th width="69.8887939453125">#</th><th width="175.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SDM01-TZM-12</td><td>SDM01 SCTA-3×120A/Φ16 Zigbee (Tuya)+RS485</td></tr><tr><td>2</td><td>SDM01-TZM-20</td><td>SDM01 SCTA-3×200A/Φ20 Zigbee (Tuya)+RS485</td></tr></tbody></table>
{% endtab %}

{% tab title="Standard Zigbee 3.0" %}

<table><thead><tr><th width="67.8887939453125">#</th><th width="186.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SDM01-TZM-12-U01</td><td>SDM01 SCTA-3×120A/Φ16 Zigbee (Std. ZB3.0)+RS485</td></tr><tr><td>2</td><td>SDM01-TZM-20-U01</td><td>SDM01 SCTA-3×200A/Φ20 Zigbee (Std. ZB3.0)+RS485</td></tr></tbody></table>
{% endtab %}

{% tab title="Open WiFi " %}

<table><thead><tr><th width="72.8887939453125">#</th><th width="178.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SDM01-EWM-12</td><td>SDM01 SCTA-3×120A/Φ16 Wi-Fi (ESP-8685)+RS485</td></tr><tr><td>2</td><td>SDM01-EWM-20</td><td>SDM01 SCTA-3×200A/Φ20 Wi-Fi (ESP-8685)+RS485</td></tr></tbody></table>

{% endtab %}
{% endtabs %}

***

### 9. FAQ&#x20;

{% content-ref url="/pages/149DFxm5iomFCS9alhv5" %}
[FAQ](/faq/overview)
{% endcontent-ref %}

***

### 10. Troubleshooting

{% content-ref url="/pages/td5Nnli4rm9AAhvTaYLk" %}
[Troubleshooting](/troubleshooting/overview)
{% endcontent-ref %}

***

### 11. Printed Document

<table data-full-width="false"><thead><tr><th width="588.5555419921875">Document</th><th>Download</th></tr></thead><tbody><tr><td>Datasheet</td><td><a href="https://downloads.bituo-technik.com/Datasheet/SDM01-Combo_Datasheet_EN.pdf">⬇️ PDF</a></td></tr><tr><td>User Guide</td><td><a href="https://downloads.bituo-technik.com/User-Guide/SDM01-All-in-One_User-Guide_EU6Languages.pdf">⬇️ PDF</a></td></tr></tbody></table>

### 12. Explore More


# SDM01 Combo Gen2

{% hint style="info" %}
**Status:** Preliminary | **Applies to:** SDM01 Gen2 Combo | **Hardware Revision:** V1.0+ | **Last Updated:** 2026-07-27
{% endhint %}

### 1.  Introduction

![](https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FAdDoZ1z6LkP8gQBjtrj0%2FSDM01G2-with-3CT_Transparent-for-Webpage.png?alt=media\&token=ef7e1e7b-4688-43ba-a841-dc498ef8360b)

The **SDM01 Combo Gen2** maintains the ultra-slim 18mm (1-module) profile for precise monitoring of three-phase or multiple single-phase circuits. Equipped with three split-core CTs, it accurately measures voltage, current, power, and energy. It supports both wired and wireless communication for flexible and seamless system integration. Its ultra-fast bi-directional power measurement makes it particularly suitable for export limiting application.

#### Product Highlights

* **Bi-directional Measurement**: Accurately monitor both imported (consumption) and exported (generation) power and energy flows.
* **Space-Saving Setup:** Features a compact 1-module width (1MW) DIN rail design, complemented by easy-to-install split-core current transformers.
* **Advanced Local Control:** Supports extensive local APIs, making it the perfect fit for Home Energy Management Systems (HEMS), dynamic load balancing (DLB), and zero-export limiting.
* **Real-time Monitoring**: Delivers live tracking of critical electrical parameters, including voltage, current, and active power.
* **Flexible Integration:** Offers seamless connectivity through multiple protocols like Wi-Fi, Zigbee, and Modbus to suit diverse system architectures.
* **Modbus Support**: Hybrid WiFi/Zigbee + Modbus variants are available for industrial installations.

#### Typical Application

* Home energy management systems (HEMS)
* energy management systems (EMS) for small business&#x20;
* Energy management systems (EMS) for buildings, Infrastructure, and Industry
* Dynamic load balancing (DLB) for electrical vehicle charging
* Export limitation for renewable power generation

***

### 2. Part Description

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2F20txVy6ZjQ9G31eh9yjg%2Fimage.png?alt=media&amp;token=a4a6c2dc-c760-435d-8886-4961161736f1" alt=""><figcaption></figcaption></figure>

<table data-header-hidden><thead><tr><th width="84.5555419921875">#</th><th width="257.666748046875">Element</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>Connector for voltage take-offs connection</td><td>The monitor is powered by AC power supply and measures voltage through four cables: X, Y, Z, and N</td></tr><tr><td>2</td><td>Connector for current transformer connection</td><td>The Red (+) and Black (-) wires of CT(X), CT(Y), and CT(Z) must match the corresponding polarity of the connector.</td></tr><tr><td>3</td><td>Connector for RS485 communication</td><td>For Modbus RTU communication</td></tr><tr><td>4</td><td>Reset button</td><td>Press and hold for 3–5 seconds to enter pairing mode.</td></tr><tr><td>5</td><td>Status LED (ACT)</td><td>Indicates device operation and network status through different flashing patterns.</td></tr><tr><td>6</td><td>Alarm LED (AL)</td><td>Flashes to indicate system alarms or errors.</td></tr><tr><td>7</td><td>Product model</td><td>Main unit product model </td></tr><tr><td>8</td><td>Locking clip for DIN rail mounting</td><td>Mounts onto a 35mm DIN rail.</td></tr><tr><td>9</td><td>Split-core CT locking clasp</td><td>Ensure the clasp is securely locked for precise measurement.</td></tr><tr><td>10</td><td>Positive power flow direction</td><td>Indicates positive power flow direction for CT(L1), CT(L1), and CT(L3) installation.</td></tr></tbody></table>

***

### 3. Technical Data

<table data-header-hidden><thead><tr><th width="342"></th><th></th></tr></thead><tbody><tr><td>Rated voltage (Input)</td><td>~220-240 VAC phase to neutral, 50/60 Hz<br>~380-415 VAC phase to phase, 50/60 Hz<sup>1)</sup></td></tr><tr><td>Max monitoring current <em>I</em><sub>max</sub></td><td>50A / 120A / 300A / 400A</td></tr><tr><td>Over-voltage category</td><td>III</td></tr><tr><td>Rated insolating voltage <em>U</em><sub>i</sub></td><td>440V</td></tr><tr><td>Rated impulse withstand voltage <em>U</em>imp</td><td>4kV</td></tr><tr><td>Pollution degree</td><td>3</td></tr><tr><td>Protection degree</td><td>IP20</td></tr><tr><td>Power Supply</td><td>100~240 VAC (L1-N)</td></tr><tr><td>Energy measurement accuracy</td><td>Class 1 (IEC 61557-12)</td></tr><tr><td>Maximum Power consumption</td><td>≤ 2VA</td></tr><tr><td>Rated operating temperature</td><td>-25℃ to 55℃</td></tr><tr><td>Main module dimension</td><td>113.7×18.0×65.9mm</td></tr><tr><td>Clamp CT apertures</td><td>Ø10 / Ø16 / Ø24 / Ø36 mm</td></tr><tr><td>Communication Type</td><td>Wireless<sup>2)</sup>: BLE+Wi-Fi; Zigbee<br>Wired: RS485</td></tr></tbody></table>

**Remark:**\
1\) Not suitable for 3P3W installation.

2\) Two variants of main module available with different connectivity - Tuya WiFI (SDM01G2-TWM-\*), and Standard Zigbee 3.0 (SDM01G2-SZM-\*)

***

### 4. Mechanical Outline

* **Dimension:** Unit in mm
* **Main Unit:** Monitoring module for DIN-rail installation (18mm width)

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FsVVBSHX2do6iPz82QDpP%2Fimage.png?alt=media&amp;token=b979d225-7bd5-4712-b600-495f8acf9b2e" alt=""><figcaption></figcaption></figure>

* **Split-core Current Transformer - 50A (CT Clamp - 50A):**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FSaY4TGxxEPzIqrrQXGyV%2FBSCT-10C-Cable-B.png?alt=media&amp;token=ff34bbc2-637e-44b0-a0bd-b6968e808763" alt=""><figcaption></figcaption></figure>

* **Split-core Current Transformer - 120A (CT Clamp - 120A):**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FL9hClaStxpxhxnl7xLx9%2FBSCT-16B-Cable-B.png?alt=media&amp;token=d2ba0ca0-4ab7-4c48-b4d2-fbbc2a15e89e" alt=""><figcaption></figcaption></figure>

* **Split-core Current Transformer - 300A (CT Clamp - 300A):**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FJXN7UEBaXeDLOfTInKtI%2FBSCT-24X.png?alt=media&amp;token=46761db4-47ef-4855-b226-556114ec94cf" alt=""><figcaption></figcaption></figure>

* **Split-core Current Transformer - 400A (CT Clamp - 400A):**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2F0uq7qDCQrQaokcflOCvU%2FBSCT-36X.png?alt=media&amp;token=54655811-5010-4cf1-9899-ac1a401be985" alt=""><figcaption></figcaption></figure>

***

### 5. Electrical Installation&#x20;

#### Wiring Diagram

**⚠️ Safety Remarks:**

* The device must be associated with easily accessible upstream protective devices ‒ such as miniature circuit breakers (MCB).
* The device must be installed, operated, serviced, and maintained **ONLY** by qualified professionals.
* Please read the user guide carefully before installation for detailed wiring diagrams and safety precautions.

<p align="center"><strong>Three-phase (3P4W) System Wiring</strong></p>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2F9ovIEMDjP6LAr3MQnPa7%2FSDM01G2-3PN-Wiring.png?alt=media&amp;token=ac05a196-30e9-4966-a7e5-697aa4cc7260" alt=""><figcaption></figcaption></figure>

<p align="center"></p>

<p align="center"><strong>Single-phase System Wiring up to 3 Branch Circuits</strong></p>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FO5abtrL6mgkEOBL5cYqR%2FSDM01G2-3-1PN-Circuits-Wiring.png?alt=media&amp;token=b9723b26-e742-4517-9e61-8a0111d229ae" alt=""><figcaption></figcaption></figure>

**Note:**&#x20;

1. Voltage measurement must match current measurement – V<sub>1</sub> (I<sub>1</sub>) ; V<sub>2</sub> (I<sub>2</sub>) ; V<sub>3</sub> (I<sub>3</sub>) , to measure electrical data correctly.
2. It can cause product damage, if the blue cable for N connection is connected to phase conductors by mistake

#### Installation Video

*🚧Coming soon...*

***

### 6. User Interface

#### Reset Button

Press and hold for 3–5 seconds to enter pairing mode.

#### LED Indicator<br>

{% tabs %}
{% tab title="Tuya WiFi " %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Device connected - the device is online and functioning normally with cloud connectivity.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect using saved network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Network connected, cloud unreachable - the device is connected to Wi-Fi/Zigbee, but failed to reach the cloud.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Alarm reminder -<br>The device has detected a fault. Please check the wiring and power supply.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fgjz0xceslVOF4qKWMqa0%2FRed-Flashing-at-1Hz.jpg?alt=media&amp;token=202171d9-496d-4264-9b50-a7ab0d175d0c">Red-Flashing-at-1Hz.jpg</a></td></tr></tbody></table>
{% endtab %}

{% tab title="Standard Zigbee 3.0" %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Zigbee connected, BLE disconnected – the device is connected to a Zigbee network while BLE is turned off or not connected.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect both BLE (if available) and Zigbee using saved settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>BLE connected(if available)  - the LED flashes at 1Hz whenever BLE is connected, regardless of Zigbee status.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>The device has detected a fault. Please check the wiring and power supply.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fgjz0xceslVOF4qKWMqa0%2FRed-Flashing-at-1Hz.jpg?alt=media&amp;token=202171d9-496d-4264-9b50-a7ab0d175d0c">Red-Flashing-at-1Hz.jpg</a></td></tr></tbody></table>
{% endtab %}
{% endtabs %}

***

### 7. System Integration

#### Wireless communication

Products equipped with different communication SoC firmwares connect to different systems and cloud platforms. Users can select the appropriate version based on their specific application requirements.

{% tabs %}
{% tab title="Tuya WiFi " %}
The Tuya WiFi version can only be integrated into the Tuya Cloud using Tuya's encrypted MQTT communication. It cannot be directly integrated with any third-party cloud platforms, ecosystems, or gateways. Third-party clouds or edge gateways need to be integrated via Tuya cloud APIs. For details, please refer to Tuya's developer documentation.

**Note:**&#x20;

1. Tuya's strategy for adjusting the cloud data reporting frequency is not fully disclosed. Based on the latest updates as of April 2026, provided the daily data reporting traffic limit is not exceeded, the fastest expected reporting interval will be between 5 to 15 minutes.
2. Tuya's Smart Life App is user-friendly and straightforward, making it ideal for entry-level smart home users who prefer simplicity and basic energy consumption monitoring.
   {% endtab %}

{% tab title="Standard Zigbee 3.0" %}
The Standard Zigbee 3.0 version can seamlessly connects to third-party gateways. Thanks to the standardized application-layer integration of Zigbee 3.0, it is highly convenient and widely applicable for both residential and commercial building projects.

Currently supported smart home ecosystems include:

* **Home Assistant:** Integration via Zigbee2MQTT [SDM01](https://www.zigbee2mqtt.io/devices/SDM01W-U01.html#bituo-technik-sdm01w-u01)
* **SmartThings:** Integration via the SmartThings Hub driver (officially approved).
* **Homey:** Integration via the [Bituo Technik App ](https://homey.app/en-us/app/com.bituotechnik.iot/BITUO-TECHNIK/)

**You can find information about the commonly used Zigbee Cluster Library on** [**this page**](https://bituo-technik.gitbook.io/hc/device-api/zigbee/spm-sdm-zigbee-profile)**.**
{% endtab %}
{% endtabs %}

#### Wired communication

SDM01 provides a Modbus RTU over RS485 interface, making it convenient to use as a wired Modbus RTU meter. You can view the Modbus RTU register address information by clicking the page below.

{% content-ref url="/pages/cIwsN5OFt26gvjZMt9c1" %}
[SDM01 Modbus RTU Map](/device-api/sdm01-modbus-rtu-map)
{% endcontent-ref %}

***

### 8. Ordering Information

{% tabs %}
{% tab title="Tuya Wi-Fi" %}

<table><thead><tr><th width="75.7777099609375">#</th><th width="175.555419921875">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SDM01G2-TWM-12</td><td>SDM01 SCTA-3×120A/Φ16 Wi-Fi (Tuya LAN+)+RS485</td></tr><tr><td>2</td><td>SDM01G2-TWM-20</td><td>SDM01 SCTA-3×200A/Φ20 Wi-Fi (Tuya LAN+)+RS485</td></tr><tr><td>3</td><td>SDM01G2-TWM-30</td><td>SDM01 SCTA-3×300A/Φ16 Wi-Fi (Tuya LAN+)+RS485</td></tr><tr><td>4</td><td>SDM01G2-TWM-40</td><td>SDM01 SCTA-3×400A/Φ20 Wi-Fi (Tuya LAN+)+RS485</td></tr></tbody></table>

1\) Tuya LAN+: Tuya LAN+ is a specific Wi-Fi SoC firmware provided by Tuya Smart that features local area network (LAN) communication. It is suitable for local LAN communication with products such as EV chargers, microinverters, and micro-energy storage systems that are also equipped with Tuya LAN+ communication firmware. This model can only be purchased through Tuya's official or designated channels.
{% endtab %}

{% tab title="Standard Zigbee 3.0" %}

<table><thead><tr><th width="67.8887939453125">#</th><th width="186.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SDM01-TZM-12-U01</td><td>SDM01 SCTA-3×120A/Φ16 Zigbee (Std. ZB3.0)+RS485</td></tr><tr><td>2</td><td>SDM01-TZM-20-U01</td><td>SDM01 SCTA-3×200A/Φ20 Zigbee (Std. ZB3.0)+RS485</td></tr></tbody></table>
{% endtab %}
{% endtabs %}

***

### 9. FAQ&#x20;

{% content-ref url="/pages/149DFxm5iomFCS9alhv5" %}
[FAQ](/faq/overview)
{% endcontent-ref %}

***

### 10. Troubleshooting

{% content-ref url="/pages/td5Nnli4rm9AAhvTaYLk" %}
[Troubleshooting](/troubleshooting/overview)
{% endcontent-ref %}

***

### 11. Printed Document

<table data-full-width="false"><thead><tr><th width="588.5555419921875">Document</th><th>Download</th></tr></thead><tbody><tr><td>Datasheet</td><td><a href="https://downloads.bituo-technik.com/Datasheet/SDM01G2-Combo_Datasheet_EN.pdf">⬇️ PDF</a></td></tr><tr><td>User Guide</td><td><a href="https://downloads.bituo-technik.com/User-Guide/SDM01G2_All-in-One-User-Guide_EU6Languages.pdf">⬇️ PDF</a></td></tr></tbody></table>

### 12. Explore More


# SDM01 G2X

{% hint style="info" %}
**Status:** Preliminary | **Applies to:** SDM01G2X  | **Hardware Revision:** V1.0+ | **Last Updated:** 2026-07-28
{% endhint %}

### 1.  Introduction

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fc8SV3y7crubytWhG6nKz%2FSDM01G2X_Ext-Antenna_for-website-300k.png?alt=media&amp;token=067cc253-85ae-4190-8840-e35b4e2a4746" alt="" width="254"><figcaption></figcaption></figure></div>

The **SDM01 G2X** is an ultra-slim 18mm energy meter for precise three-phase or multiple single-phase monitoring. It delivers high-speed reporting for dynamic load balancing and export limiting, alongside an external antenna for reliable connectivity.

#### Product Highlights

* **Bi-directional Power Tracking:** Delivers high-precision bi-directional monitoring for both imported energy and exported power generation.
* **Minimalist 1MW Design:** Effortlessly fits into space-constrained distribution boxes, utilizing snap-on split-core CTs for rapid, non-intrusive installation.
* **Real-Time Monitoring:** Provides continuous, live tracking of critical electrical metrics, including voltage, current, and active power.
* **Local WiFi API for HEMS:** The dedicated WiFi variant features robust local APIs, seamlessly driving dynamic load balancing (DLB) and export limitation.
* **Long-Range LoRaWAN Integration:** The LoRaWAN variant ensures reliable, long-distance data transmission, making it the ideal choice for large-scale building and infrastructure monitoring.

#### Typical Application

* Home energy management systems (HEMS)
* energy management systems (EMS) for small business&#x20;
* Energy management systems (EMS) for buildings, Infrastructure, and Industry
* Dynamic load balancing (DLB) for electrical vehicle charging
* Export limitation for renewable power generation

***

### 2. Part Description

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FEHEl6VMzHEDvJlaMLiYh%2Fimage.png?alt=media&amp;token=d67c360a-0e07-4d89-a788-97d6b98fd688" alt=""><figcaption></figcaption></figure>

<table data-header-hidden><thead><tr><th width="84.5555419921875">#</th><th width="257.666748046875">Element</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>Connector for voltage take-offs connection</td><td>The monitor is powered by AC power supply and measures voltage through four cables: X, Y, Z, and N</td></tr><tr><td>2</td><td>Connector for current transformer connection</td><td>The Red (+) and Black (-) wires of CT(X), CT(Y), and CT(Z) must match the corresponding polarity of the connector.</td></tr><tr><td>3</td><td> External Antenna Connector</td><td>For Wireless communication</td></tr><tr><td>4</td><td>Reset button</td><td>Press and hold for 3–5 seconds to enter pairing mode.</td></tr><tr><td>5</td><td>Status LED (ACT)</td><td>Indicates device operation and network status through different flashing patterns.</td></tr><tr><td>6</td><td>Alarm LED (AL)</td><td>Flashes to indicate system alarms or errors.</td></tr><tr><td>7</td><td>Product Model</td><td>Main unit product model </td></tr><tr><td>8</td><td>Locking clip for DIN rail mounting</td><td>Mounts onto a 35mm DIN rail.</td></tr><tr><td>9</td><td>Split-core CT locking clasp</td><td>Ensure the clasp is securely locked for precise measurement.</td></tr><tr><td>10</td><td>Positive power flow direction</td><td>Indicates positive power flow direction for CT(L1), CT(L1), and CT(L3) installation.</td></tr></tbody></table>

***

### 3. Technical Data

<table data-header-hidden><thead><tr><th width="342"></th><th></th></tr></thead><tbody><tr><td>Rated voltage (Input)</td><td>~220-240 VAC phase to neutral, 50/60 Hz<br>~380-415 VAC phase to phase, 50/60 Hz<sup>1)</sup></td></tr><tr><td>Max monitoring current <em>I</em><sub>max</sub></td><td>50A / 120A / 300A / 400A</td></tr><tr><td>Over-voltage category</td><td>III</td></tr><tr><td>Rated insolating voltage <em>U</em><sub>i</sub></td><td>440V</td></tr><tr><td>Rated impulse withstand voltage <em>U</em>imp</td><td>4kV</td></tr><tr><td>Pollution degree</td><td>3</td></tr><tr><td>Power Supply</td><td>100~240 VAC (L1-N)</td></tr><tr><td>Protection degree</td><td>IP20</td></tr><tr><td>Energy measurement accuracy</td><td>Class 1 (IEC 61557-12)</td></tr><tr><td>Maximum Power consumption</td><td>≤ 2VA</td></tr><tr><td>Rated operating temperature</td><td>-25℃ to 55℃</td></tr><tr><td>Main module dimension</td><td>113.7×18.0×65.9mm</td></tr><tr><td>Clamp CT apertures</td><td>Ø10 / Ø16 / Ø24 / Ø36 mm</td></tr><tr><td>Communication Type</td><td>BLE+Wi-Fi; BLE+LoRaWAN</td></tr></tbody></table>

**Remark:**\
1\) Not suitable for 3P3W installation.

***

### 4. Mechanical Outline

* **Dimension:** Unit in mm
* **Main Unit:** Monitoring module for DIN-rail installation (18mm width)

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FmDGhbqihfdG5MZQ79uZk%2FSDM01G2X-Main_Mechnical-With-Number.png?alt=media&amp;token=c1ebb93d-2690-4830-825b-b820b6d0e087" alt="" width="563"><figcaption></figcaption></figure>

* **Split-core Current Transformer - 50A (CT Clamp - 50A):**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FSaY4TGxxEPzIqrrQXGyV%2FBSCT-10C-Cable-B.png?alt=media&amp;token=ff34bbc2-637e-44b0-a0bd-b6968e808763" alt=""><figcaption></figcaption></figure>

* **Split-core Current Transformer - 120A (CT Clamp - 120A):**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FL9hClaStxpxhxnl7xLx9%2FBSCT-16B-Cable-B.png?alt=media&amp;token=d2ba0ca0-4ab7-4c48-b4d2-fbbc2a15e89e" alt=""><figcaption></figcaption></figure>

* **Split-core Current Transformer - 300A (CT Clamp - 300A):**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FJXN7UEBaXeDLOfTInKtI%2FBSCT-24X.png?alt=media&amp;token=46761db4-47ef-4855-b226-556114ec94cf" alt=""><figcaption></figcaption></figure>

* **Split-core Current Transformer - 400A (CT Clamp - 400A):**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2F0uq7qDCQrQaokcflOCvU%2FBSCT-36X.png?alt=media&amp;token=54655811-5010-4cf1-9899-ac1a401be985" alt=""><figcaption></figcaption></figure>

***

### 5. Electrical Installation&#x20;

#### Wiring Diagram

**⚠️ Safety Remarks:**

* The device must be associated with easily accessible upstream protective devices ‒ such as miniature circuit breakers (MCB).
* The device must be installed, operated, serviced, and maintained **ONLY** by qualified professionals.
* Please read the user guide carefully before installation for detailed wiring diagrams and safety precautions.

<p align="center"><strong>Three-phase (3P4W) System Wiring</strong></p>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FucRpGwFs9IKuxjIvNuBy%2FSDM01G2X-3PN-Wiringpng.png?alt=media&amp;token=7df5bd81-4f4b-4fd7-994b-04e6d6a7de87" alt=""><figcaption></figcaption></figure>

<p align="center"></p>

<p align="center"><strong>Single-phase System Wiring up to 3 Branch Circuits</strong></p>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FbdOR8Pb6nRm27Oa33pzA%2FSDM01G2X-3x1PN-Wiring.png?alt=media&amp;token=ab4e9522-737f-40bb-842d-54f4467da442" alt=""><figcaption></figcaption></figure>

**Note:**&#x20;

1. Voltage measurement must match current measurement – V<sub>1</sub> (I<sub>1</sub>) ; V<sub>2</sub> (I<sub>2</sub>) ; V<sub>3</sub> (I<sub>3</sub>) , to measure electrical data correctly.
2. It can cause product damage, if the blue cable for N connection is connected to phase conductors by mistake

#### Installation Video

*🚧Coming soon...*

***

### 6. User Interface

#### Reset Button

Press and hold for 3–5 seconds to enter pairing mode.

#### LED Indicator

{% tabs %}
{% tab title="Tuya WiFi " %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Device connected - the device is online and functioning normally with cloud connectivity.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect using saved network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Network connected, cloud unreachable - the device is connected to Wi-Fi/Zigbee, but failed to reach the cloud.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Alarm reminder -<br>The device has detected a fault. Please check the wiring and power supply.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fgjz0xceslVOF4qKWMqa0%2FRed-Flashing-at-1Hz.jpg?alt=media&amp;token=202171d9-496d-4264-9b50-a7ab0d175d0c">Red-Flashing-at-1Hz.jpg</a></td></tr></tbody></table>
{% endtab %}

{% tab title="Open WiFi" %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Wi-Fi connected, BLE disconnected - the device is connected to Wi-Fi while BLE is disconnected.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect both BLE and Wi-Fi using saved settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>BLE connected - the LED flashes at 1Hz whenever BLE is connected, regardless of Wi-Fi status.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Alarm reminder -<br>The device has detected a fault. Please check the wiring and power supply.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fgjz0xceslVOF4qKWMqa0%2FRed-Flashing-at-1Hz.jpg?alt=media&amp;token=202171d9-496d-4264-9b50-a7ab0d175d0c">Red-Flashing-at-1Hz.jpg</a></td></tr></tbody></table>
{% endtab %}
{% endtabs %}

***

### 7. System Integration

#### Wireless communication

Products equipped with different communication SoC firmwares connect to different systems and cloud platforms. Users can select the appropriate version based on their specific application requirements.

{% tabs %}
{% tab title="Tuya WiFi " %}
The Tuya WiFi version can only be integrated into the Tuya Cloud using Tuya's encrypted MQTT communication. It cannot be directly integrated with any third-party cloud platforms, ecosystems, or gateways. Third-party clouds or edge gateways need to be integrated via Tuya cloud APIs. For details, please refer to Tuya's developer documentation.

**Note:**&#x20;

1. Tuya's strategy for adjusting the cloud data reporting frequency is not fully disclosed. Based on the latest updates as of April 2026, provided the daily data reporting traffic limit is not exceeded, the fastest expected reporting interval will be between 5 to 15 minutes.
2. Tuya's Smart Life App is user-friendly and straightforward, making it ideal for entry-level smart home users who prefer simplicity and basic energy consumption monitoring.
   {% endtab %}

{% tab title="Open WiFi" %}
The Open Wi-Fi version of SDM01 provides the following open APIs (refer to the Device API document), enabling users to implement local automation and connect to custom cloud platforms.

1. **Zero-Configuration Discovery Mechanism (LAN Addressing)**
   * **mDNS / DNS-SD:** Supports automatic discovery of the energy meter by EV chargers and PV inverters on the Local Area Network (LAN) without the need for IP scanning.
2. **BLE Near-Field Communication Mode (Offline/Maintenance)**
   * **BLE GATT (Time-limited activation):** Requires PIN code + PAKE algorithm authentication for local high-privilege configuration and network resets. Wakes up on demand and closes upon timeout.
   * **BLE Broadcast (Always-on 24/7):** Unidirectional broadcast of AES-encrypted real-time power data, allowing nearby low-power devices to listen with zero latency and without requiring a connection.
3. **LAN Standard Mode (Ultra-low Latency Device Communication)** *Plaintext or lightweight encryption for local networks.*
   * **Modbus TCP:** Used for local linkage with EV chargers and PV inverters.
   * **Local MQTT:** Used for local integration with open-source smart home ecosystems.
   * **WebSocket (WS) / Raw UDP:** Ultra-high frequency real-time power streaming subscription (enables DLB completion within 1-2 seconds).
   * **HTTP / CoAP:** Suitable for low-frequency parameter configuration and status queries.
4. **Cloud Device Access Layer (Device-to-Cloud / Southbound API)**
   * **MQTTS (MQTT over TLS 1.2/1.3):** Core main communication link.
   * **HTTPS (OTA dedicated):** Exclusively used for downloading large Over-The-Air (OTA) firmware upgrade packages.
     {% endtab %}
     {% endtabs %}

***

### 8. Ordering Information

{% tabs %}
{% tab title="Tuya Wi-Fi" %}

<table><thead><tr><th width="58.7777099609375">#</th><th width="195.555419921875">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SDM01G2X-TW-12</td><td>SDM01G2X SCTA-3×120A/Φ16 Wi-Fi (Tuya LAN+)</td></tr><tr><td>2</td><td>SDM01G2X-TW-20</td><td>SDM01G2X SCTA-3×200A/Φ20 Wi-Fi (Tuya LAN+)</td></tr><tr><td>3</td><td>SDM01G2X-TW-30</td><td>SDM01G2X SCTA-3×300A/Φ16 Wi-Fi (Tuya LAN+)</td></tr><tr><td>4</td><td>SDM01G2X-TW-40</td><td>SDM01G2X SCTA-3×400A/Φ20 Wi-Fi (Tuya LAN+)</td></tr></tbody></table>

1\) Tuya LAN+: Tuya LAN+ is a specific Wi-Fi SoC firmware provided by Tuya Smart that features local area network (LAN) communication. It is suitable for local LAN communication with products such as EV chargers, microinverters, and micro-energy storage systems that are also equipped with Tuya LAN+ communication firmware. This model can only be purchased through Tuya's official or designated channels.
{% endtab %}

{% tab title="Open Wi-Fi" %}

<table><thead><tr><th width="58.7777099609375">#</th><th width="195.555419921875">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SDM01G2X-EW-12</td><td>SDM01G2X SCTA-3×120A/Φ16 Open Wi-Fi</td></tr><tr><td>2</td><td>SDM01G2X-EW-20</td><td>SDM01G2X SCTA-3×200A/Φ20 Open Wi-Fi</td></tr><tr><td>3</td><td>SDM01G2X-EW-30</td><td>SDM01G2X SCTA-3×300A/Φ16 Open Wi-Fi</td></tr><tr><td>4</td><td>SDM01G2X-EW-40</td><td>SDM01G2X SCTA-3×400A/Φ20 Open Wi-Fi</td></tr></tbody></table>
{% endtab %}
{% endtabs %}

***

***

### 9. FAQ&#x20;

{% content-ref url="/pages/149DFxm5iomFCS9alhv5" %}
[FAQ](/faq/overview)
{% endcontent-ref %}

***

### 10. Troubleshooting

{% content-ref url="/pages/td5Nnli4rm9AAhvTaYLk" %}
[Troubleshooting](/troubleshooting/overview)
{% endcontent-ref %}

***

### 11. Printed Document

<table data-full-width="false"><thead><tr><th width="588.5555419921875">Document</th><th>Download</th></tr></thead><tbody><tr><td>Datasheet</td><td><a href="https://downloads.bituo-technik.com/Datasheet/SDM01G2X_Datasheet_EN.pdf">⬇️ PDF</a></td></tr><tr><td>User Guide</td><td><a href="https://downloads.bituo-technik.com/User-Guide/SDM01G2X_All-in-One_User-Guide_EU6Languages.pdf">⬇️ PDF</a></td></tr></tbody></table>

### 12. Explore More


# SDM02 SP

{% hint style="info" %}
&#x20;**Applies to:** SDM02 SP | **Hardware Revision:** V1.0+ | **Last Updated:** 2026-05-12
{% endhint %}

### 1.  Introduction

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FUs8LiwCj33swbH2oysvi%2Fimage.png?alt=media&amp;token=451cc34a-0287-47a9-a8a3-49b8cbe6d304" alt="" width="300"><figcaption></figcaption></figure></div>

The SDM02 is a compact smart energy monitor designed for split-phase and two-phase systems. Using two split-core CTs, it provides precise measurement of voltage, current, power, and energy. With integrated wireless communication, it offers effortless integration into smart energy ecosystems.

#### Product Highlights

* **Universal Compatibility**: Seamlessly fits both UL Split-phase and IEC/UL 2×1P+N systems, making it a versatile choice for diverse electrical setups.
* **Real-Time Monitoring**: Monitor voltage, current, power, and power factor instantly. Gain actionable insights to optimize your energy usage and reduce electricity bills.
* **Bi-Directional Measurement**: Perfect for homes with solar panels. Accurately track both the energy you consume from the grid and the power you generate.
* **High-Precision Accuracy**: Trust your data. Delivers Class 1 active energy measurement accuracy, fully compliant with IEC 61557-12 standards.
* **Versatile Connectivity**: Choose from various communication options such as Wi-Fi and Zigbee, catering to diverse system integration needs.

#### Typical Application

* Home energy management systems (HEMS)
* energy management systems (EMS) for small business&#x20;
* Dynamic load balancing (DLB) for electrical vehicle charging

***

### 2. Part Description

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2F3goGEshUrG2QucodGUqi%2Fimage.png?alt=media&amp;token=b8d87ef7-1f50-4489-a12c-3db1ff7f9817" alt=""><figcaption></figcaption></figure>

<table data-header-hidden><thead><tr><th width="66.5555419921875">#</th><th width="257.666748046875">Element</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>Pluggable terminal for the wire of voltage</td><td>The monitor is powered by 110~240VAC power supply and measures voltage through three cables: L<sub>1</sub>, L<sub>2</sub>, and N</td></tr><tr><td>2</td><td>Pluggable terminal for the wire of current transformer</td><td>The Red (+) and Black (-) wires of CT(1) and CT(2) must match the corresponding polarity of the connector.</td></tr><tr><td>3</td><td>Reset button</td><td>Press and hold for 3–5 seconds to enter pairing mode.</td></tr><tr><td>4</td><td>Status LED (ACT)</td><td>Indicates device operation and network status through different flashing patterns.</td></tr><tr><td>5</td><td>Product QR code</td><td>Contains manufacturing batch information.</td></tr><tr><td>6</td><td>Product model</td><td>See “Ordering Information” section for product selection</td></tr><tr><td>7</td><td>Calibration ID</td><td>The calibration ID on the split-core CT must match the one on the monitor for optimal accuracy.</td></tr><tr><td>8</td><td>Split-core CT locking clasp</td><td>Ensure the clasp is securely locked for precise measurement.</td></tr><tr><td>9</td><td>Positive power flow direction</td><td>Indicates positive power flow direction for CT(1) and CT(2) installation.</td></tr></tbody></table>

***

### 3. Technical Data

| Rated operating voltage *U*<sub>n</sub>  | <p>\~110-240 VAC L-N, 50/60 Hz</p><p>\~208-240 VAC L1-L2, 50/60 Hz</p> |
| ---------------------------------------- | ---------------------------------------------------------------------- |
| Max current *I*<sub>max</sub>            | 120A / 200A                                                            |
| Over-voltage category                    | III                                                                    |
| Rated insolating voltage *U*<sub>i</sub> | 250V                                                                   |
| Rated impulse withstand voltage *U*imp   | 4kV                                                                    |
| Pollution degree                         | 3                                                                      |
| Protection degree                        | IP20                                                                   |
| Energy measurement accuracy              | Class 1 (IEC 61557-12)                                                 |
| Maximum Power consumption                | ≤ 2VA                                                                  |
| Rated operating temperature              | -25℃ to 55℃                                                            |
| Main module dimension                    | 42.2×41.6×20mm                                                         |
| Clamp CT apertures                       | Ø16mm / Ø20mm                                                          |
| Communication Type                       | BLE; Wi-Fi; Zigbee                                                     |

***

### 4. Mechanical Outline

* **Dimension:** Unit in mm
* **Main Unit:** Monitoring module&#x20;

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FNjcuIQEmMF58DB9vsnqu%2Fimage.png?alt=media&amp;token=a414d5f1-a22c-452c-8f6f-e4b378dbe6e4" alt="" width="563"><figcaption></figcaption></figure>

* **Split-core Current Transformer - 120A (CT Clamp - 120A):**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FEMNc27n6KlpdLzKVdJtD%2Fimage.png?alt=media&amp;token=56f51d22-7def-4630-983c-ef826897791a" alt=""><figcaption></figcaption></figure>

* **Split-core Current Transformer - 200A (CT Clamp - 200A):**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FnSdF3ymrj0Tw5NFLOgEF%2Fimage.png?alt=media&amp;token=d2edbc09-3b1a-44d7-848c-8a14a5a776a3" alt=""><figcaption></figcaption></figure>

***

### 5. Electrical Installation&#x20;

#### Wiring Diagram

**⚠️ Safety Remarks:**

* The device must be associated with easily accessible upstream protective devices ‒ such as miniature circuit breakers (MCB).
* Designed for Split-phase systems (1P3W) and Single-phase systems (1P2W). NOT compatible with IEC Three-phase systems (380\~415 VAC L-L, 50/60 Hz).
* The device must be installed, operated, serviced, and maintained **ONLY** by qualified professionals.
* Please read the user guide carefully before installation for detailed wiring diagrams and safety precautions.

{% columns %}
{% column %}

<p align="center"><strong>UL Split-phase System Wiring</strong></p>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FyvQ0txwbp7KnFfJ9edtm%2FSDM02-UL-Split-phase-System-Wiring_EN_V1.0_2602.jpg?alt=media&amp;token=97a46f60-58b8-4723-a80a-35c08f743a6d" alt=""><figcaption></figcaption></figure>
{% endcolumn %}

{% column %}
**UL/IEC 1P+N System up to 2 Branches**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FMTVjfxS0zXsp3VkDRskC%2FSDM02-ULIEC-1PN-System-up-to-2-Branch-Circuits_EN_V1.0_2602.jpg?alt=media&amp;token=235d8d47-76a7-41d7-887b-b65b8260aadc" alt=""><figcaption></figcaption></figure>
{% endcolumn %}
{% endcolumns %}

#### Installation Video

{% embed url="<https://youtu.be/V4HpiLrXcSA>" %}

***

### 6. User Interface

#### Reset Button

Press and hold for 3–5 seconds to enter pairing mode.

#### LED Indicator

{% tabs %}
{% tab title="Tuya WiFi " %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Device connected - the device is online and functioning normally with cloud connectivity.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect using saved network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Network connected, cloud unreachable - the device is connected to Wi-Fi/Zigbee, but failed to reach the cloud.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Alarm reminder -<br>The device has detected a fault. Please check the wiring and power supply.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fgjz0xceslVOF4qKWMqa0%2FRed-Flashing-at-1Hz.jpg?alt=media&amp;token=202171d9-496d-4264-9b50-a7ab0d175d0c">Red-Flashing-at-1Hz.jpg</a></td></tr></tbody></table>
{% endtab %}

{% tab title="Tuya Zigbee" %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Device connected - the device is online and functioning normally with cloud connectivity.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect using saved network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Network connected, cloud unreachable - the device is connected to Wi-Fi/Zigbee, but failed to reach the cloud.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Alarm reminder -<br>The device has detected a fault. Please check the wiring and power supply.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fgjz0xceslVOF4qKWMqa0%2FRed-Flashing-at-1Hz.jpg?alt=media&amp;token=202171d9-496d-4264-9b50-a7ab0d175d0c">Red-Flashing-at-1Hz.jpg</a></td></tr></tbody></table>
{% endtab %}

{% tab title="Standard Zigbee 3.0" %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Zigbee connected, BLE disconnected – the device is connected to a Zigbee network while BLE is turned off or not connected.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect both BLE (if available) and Zigbee using saved settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>BLE connected(if available)  - the LED flashes at 1Hz whenever BLE is connected, regardless of Zigbee status.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>The device has detected a fault. Please check the wiring and power supply.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fgjz0xceslVOF4qKWMqa0%2FRed-Flashing-at-1Hz.jpg?alt=media&amp;token=202171d9-496d-4264-9b50-a7ab0d175d0c">Red-Flashing-at-1Hz.jpg</a></td></tr></tbody></table>
{% endtab %}

{% tab title="Open WiFi" %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Wi-Fi connected, BLE disconnected - the device is connected to Wi-Fi while BLE is disconnected.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect both BLE and Wi-Fi using saved settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>BLE connected - the LED flashes at 1Hz whenever BLE is connected, regardless of Wi-Fi status.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Alarm reminder -<br>The device has detected a fault. Please check the wiring and power supply.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fgjz0xceslVOF4qKWMqa0%2FRed-Flashing-at-1Hz.jpg?alt=media&amp;token=202171d9-496d-4264-9b50-a7ab0d175d0c">Red-Flashing-at-1Hz.jpg</a></td></tr></tbody></table>
{% endtab %}
{% endtabs %}

***

### 7. System Integration

Products equipped with different communication SoC firmwares connect to different systems and cloud platforms. Users can select the appropriate version based on their specific application requirements.

{% tabs %}
{% tab title="Tuya WiFi " %}
The Tuya WiFi version can only be integrated into the Tuya Cloud using Tuya's encrypted MQTT communication. It cannot be directly integrated with any third-party cloud platforms, ecosystems, or gateways. Third-party clouds or edge gateways need to be integrated via Tuya cloud APIs. For details, please refer to Tuya's developer documentation.

**Note:**

1. Tuya's strategy for adjusting the cloud data reporting frequency is not fully disclosed. Based on the latest updates as of April 2026, provided the daily data reporting traffic limit is not exceeded, the fastest expected reporting interval will be between 5 to 15 minutes.
2. Tuya's Smart Life App is user-friendly and straightforward, making it ideal for entry-level smart home users who prefer simplicity and basic energy consumption monitoring.
   {% endtab %}

{% tab title="Tuya Zigbee" %}
For standard operation, the Tuya Zigbee version must be integrated with a Tuya gateway, which then connects to the Tuya Cloud via Tuya's encrypted MQTT communication.

**Note:**

1. Tuya's strategy for adjusting the cloud data reporting frequency is not fully disclosed. Based on the latest updates as of April 2026, provided the daily data reporting traffic limit is not exceeded, the fastest expected reporting interval will be between 5 to 15 minutes.
2. There are unofficial methods available on the market to integrate Tuya Zigbee products with third-party gateways or hubs - such as Home Assistant integration via Zigbee2MQTT. However, please be aware of the following potential issues when using these unofficial integration methods:

* **⚠️Network Congestion:** Tuya's proprietary Zigbee data transmission strategy does not bundle data packets. Consequently, high-frequency reporting of the extensive electrical data types from several energy meters, which generate significantly more data than typical smart home Zigbee devices, can easily cause Zigbee network congestion.
* **⚠️Security Risks:** Integrating with third-party Zigbee gateways using the default global Trust Centre Link Key “*ZigbeeAlliance09*” poses potential information security risks. Therefore, using non-Tuya gateways in commercial projects is highly discouraged. For third-party gateway integration, the **Standard Zigbee 3.0** version with Install Code is strongly recommended.
  {% endtab %}

{% tab title="Standard Zigbee 3.0" %}
The Standard Zigbee 3.0 version can seamlessly connects to third-party gateways. Thanks to the standardized application-layer integration of Zigbee 3.0, it is highly convenient and widely applicable for both residential and commercial building projects.

Currently supported smart home ecosystems include:

* **Home Assistant:** Integration via Zigbee2MQTT ([SPM01](https://www.zigbee2mqtt.io/devices/SPM02-U01.html#bituo-technik-spm02-u01), [SPM02](https://www.zigbee2mqtt.io/devices/SPM02-U01.html#bituo-technik-spm02-u01), [SDM01](https://www.zigbee2mqtt.io/devices/SDM01W-U01.html#bituo-technik-sdm01w-u01), and [SDM02](https://www.zigbee2mqtt.io/devices/SDM02-U01.html#bituo-technik-sdm02-u01))
* **SmartThings:** Integration via the SmartThings Hub driver (officially approved).
* **Homey:** Integration via the [Bituo Technik App ](https://homey.app/en-us/app/com.bituotechnik.iot/BITUO-TECHNIK/)

**You can find information about the commonly used Zigbee Cluster Library on** [**this page**](https://bituo-technik.gitbook.io/hc/device-api/zigbee/spm-sdm-zigbee-profile)**.**
{% endtab %}

{% tab title="Open WiFi" %}
The Open Wi-Fi version of SDM01 provides the following open APIs (refer to the Device API document), enabling users to implement local automation and connect to custom cloud platforms.

1. **Zero-Configuration Discovery Mechanism (LAN Addressing)**
   * **mDNS / DNS-SD:** Supports automatic discovery of the energy meter by EV chargers and PV inverters on the Local Area Network (LAN) without the need for IP scanning.
2. **BLE Near-Field Communication Mode (Offline/Maintenance)**
   * **BLE GATT (Time-limited activation):** Requires PIN code + PAKE algorithm authentication for local high-privilege configuration and network resets. Wakes up on demand and closes upon timeout.
   * **BLE Broadcast (Always-on 24/7):** Unidirectional broadcast of AES-encrypted real-time power data, allowing nearby low-power devices to listen with zero latency and without requiring a connection.
3. **LAN Standard Mode (Ultra-low Latency Device Communication)** *Plaintext or lightweight encryption for local networks.*
   * **Modbus TCP:** Used for local linkage with EV chargers and PV inverters.
   * **Local MQTT:** Used for local integration with open-source smart home ecosystems.
   * **WebSocket (WS) / Raw UDP:** Ultra-high frequency real-time power streaming subscription (enables DLB completion within 1-2 seconds).
   * **HTTP / CoAP:** Suitable for low-frequency parameter configuration and status queries.
4. **Cloud Device Access Layer (Device-to-Cloud / Southbound API)**
   * **MQTTS (MQTT over TLS 1.2/1.3):** Core main communication link.
   * **HTTPS (OTA dedicated):** Exclusively used for downloading large Over-The-Air (OTA) firmware upgrade packages.
     {% endtab %}
     {% endtabs %}

### 8. Ordering Information

{% tabs %}
{% tab title="Tuya Wi-Fi" %}

<table><thead><tr><th width="75.7777099609375">#</th><th width="176.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SDM02-TW-12</td><td>SDM02 SCTA-2×120A/Φ16 Wi-Fi (Tuya)</td></tr><tr><td>2</td><td>SDM02-TW-20</td><td>SDM02 SCTA-2×200A/Φ20 Wi-Fi (Tuya)</td></tr></tbody></table>
{% endtab %}

{% tab title="Tuya Zigbee" %}

<table><thead><tr><th width="75.7777099609375">#</th><th width="176.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SDM02-TZ-12</td><td>SDM02 SCTA-2×120A/Φ16 Zigbee (Tuya)</td></tr><tr><td>2</td><td>SDM02-TZ-20</td><td>SDM02 SCTA-2×200A/Φ20 Zigbee (Tuya)</td></tr></tbody></table>
{% endtab %}

{% tab title="Standard Zigbee 3.0" %}

<table><thead><tr><th width="67.8887939453125">#</th><th width="186.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SDM02-TZ-12-U01</td><td>SDM02 SCTA-2×120A/Φ16 Zigbee (Std. ZB3.0)</td></tr><tr><td>2</td><td>SDM02-TZ-20-U01</td><td>SDM02 SCTA-2×200A/Φ20 Zigbee (Std. ZB3.0)</td></tr></tbody></table>
{% endtab %}

{% tab title="Open WiFi " %}

<table><thead><tr><th width="75.7777099609375">#</th><th width="176.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SDM02-EW-12</td><td>SDM02 SCTA-2×120A/Φ16 Wi-Fi (ESP-8685)</td></tr><tr><td>2</td><td>SDM02-EW-20</td><td>SDM02 SCTA-2×200A/Φ20 Wi-Fi (ESP-8685)</td></tr></tbody></table>
{% endtab %}
{% endtabs %}

### 9. FAQ&#x20;

{% content-ref url="/pages/149DFxm5iomFCS9alhv5" %}
[FAQ](/faq/overview)
{% endcontent-ref %}

***

### 10. Troubleshooting

{% content-ref url="/pages/td5Nnli4rm9AAhvTaYLk" %}
[Troubleshooting](/troubleshooting/overview)
{% endcontent-ref %}

***

### 11. Printed User Guide

<table data-full-width="false"><thead><tr><th width="588.5555419921875">Document</th><th>Download</th></tr></thead><tbody><tr><td>Datasheet</td><td><a href="https://downloads.bituo-technik.com/Datasheet/SDM02_Datasheet_EN.pdf">⬇️ PDF</a></td></tr><tr><td>User Guide (IEC)</td><td><a href="https://downloads.bituo-technik.com/User-Guide/SDM02-IEC-All-in-One_User-Guide_EU6Languages.pdf">⬇️ PDF</a><br></td></tr><tr><td>User Guide (UL)</td><td><a href="https://downloads.bituo-technik.com/User-Guide/SDM02_UL-User-Guide_EN.pdf">⬇️ PDF</a></td></tr></tbody></table>

***

### 12. Explore More


# SRS Series

## SRS Series — Smart Relay Switches with Built-in Power Metering

Compact puck-style smart relay switches with integrated per-channel power monitoring. Designed for flush-mounted wall boxes and ceiling installations — no changes to existing switch panels required.

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2F6ZpNQ64FYzl4MVxj6vS6%2Fimgi_10_SRS01-and-02-Home-2_3%20(1).webp?alt=media&amp;token=7802c4b2-c35b-40e6-a606-502bd05762ff" alt=""><figcaption></figcaption></figure>

***

### Product Variants

SRS products are defined across **two dimensions**:

#### 1. Channel Configuration

|                            | **SRS01 1PM**         | **SRS01 2PM**            |
| -------------------------- | --------------------- | ------------------------ |
| **Relay Channels**         | 1 × 16A               | 2 × 10A (max 16A total)  |
| **Power Monitoring**       | 1 channel             | 2 channels independently |
| **Rated Voltage**          | 110–240 VAC, 50/60 Hz | 110–240 VAC, 50/60 Hz    |
| **Type of Switching**      | Relay, Micro gap (μ)  | Relay, Micro gap (μ)     |
| **Dimension**              | 38 × 42 × 16 mm       | 38 × 42 × 16 mm          |
| **Active Energy Accuracy** | ±2%                   | ±2%                      |

#### 2. Connectivity

**Wireless** — select one variant per order:

<table><thead><tr><th width="116">Variant</th><th width="137">Communication</th><th width="235">Archetecture</th><th>API Style</th><th width="140">Typical Users</th></tr></thead><tbody><tr><td><strong>Tuya Wi-Fi</strong> (<code>*TW</code>)</td><td>Wi-Fi</td><td>BK7238 SoC (Tuya Firmware, Slave) + Metering MCU (Bituo Firmware, Master)</td><td>MQTT(Tuya Proprietary)</td><td>Tuya ecosystem, IoT beginners</td></tr><tr><td><strong>Std. Zigbee</strong> (<code>*TZ-U01</code>)</td><td>Zigbee 3.0</td><td>EFR32MG21 SoC (Bituo Firmware, Master) + Metering MCU (Bituo Firmware, Slave)</td><td>Standard Zigbee 3.0 Clusters</td><td>System Integrators, DIYers</td></tr></tbody></table>

> ℹ️ Open Wi-Fi and Tuya Zigbee versions are not currently offered for SRS — no suitable modules of sufficient compact size is available for this form factor at this time.

***

### Sub Pages

<table><thead><tr><th width="186">Model</th><th>Description</th></tr></thead><tbody><tr><td><a data-mention href="/product-document/srs-series/srs01-1pm">SRS01-1PM</a></td><td>Single-channel, 16A, with power monitoring</td></tr><tr><td><a data-mention href="/product-document/srs-series/srs01-2pm">SRS01-2PM</a></td><td>Dual-channel, 2×10A, with independent per-channel monitoring</td></tr></tbody></table>

***

### Related


# SRS01-1PM

{% hint style="info" %}
&#x20;**Applies to:** SRS01 1PM | **Hardware Revision:** V1.0+ | **Last Updated:** 2026-05-27
{% endhint %}

### 1.  Introduction

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FiQwN44iYuMnfzNIO5iMH%2FSRS01-1PM-45-Degree_EN_V1.0_2602.jpg?alt=media&amp;token=5123ab9d-6cb8-4db6-a105-f3489104b993" alt="" width="171"><figcaption></figcaption></figure></div>

**SRS01 1PM** is a compact single-channel relay switch with integrated power monitoring and wireless communication. It provides real-time measurement of voltage, current, power, and energy, making it ideal for smart home automation and lighting control.

#### Product Highlights

* **Mini Retrofit Design:** Ultra-compact (38×42×16mm) fits behind existing switches. Supports 16A max load, keeping your original switch style while adding smart control.
* **Real-time Monitoring:** Measures real-time voltage, current, power, and energy for precise consumption tracking across home and commercial devices.
* **16A Control Support:** Works with both toggle and momentary switches. Control lights via App or physical wall switch simultaneously without conflict.
* **Flexible Connectivity:** Available in 3 editions to match your needs: Tuya Wi-Fi (Easy App), Matter over Wi-Fi, or Open Wi-Fi <-> Standard Zigbee 3.0 Switchable.
* **Built-in Safety:** Equipped with over-temperature, over-current, and over-voltage protection to extend product lifespan and minimize failure risks.

#### Typical Applications

* Smart Lighting: Install behind the roof or wall switches
* Smart Appliance control: Control pumps, boilers, and appliances easily
* Smart HVAC: Automate fans, heaters, and ventilation systems

***

### 2. Part Description

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FiF9Z5tA2JdGDOEVylLjM%2Fimage.png?alt=media&amp;token=d1d4c701-64b9-4bc7-b3d5-709e2a912e19" alt="" width="563"><figcaption></figcaption></figure>

<table><thead><tr><th width="84.5555419921875">#</th><th width="279.3333740234375">Element</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>Terminal Block(Screw Terminal)</td><td>Wiring terminals for connecting Live, Neutral, and switch input wires</td></tr><tr><td>2</td><td>Reset button</td><td>Press the button 3~5 seconds to enter the pairing mode</td></tr><tr><td>3</td><td>LED</td><td>Shows device operation and network status through different flashing patterns <sup>1)</sup></td></tr><tr><td>4</td><td>Product model</td><td>Refer to the ‘Ordering Information’ section for product selection</td></tr></tbody></table>

Remark:

1\) Refer to the user guide of your selected models for detailed LED status indicators.

***

### 3. Technical Data

<table><thead><tr><th width="362">Parameter</th><th>Specification</th></tr></thead><tbody><tr><td>Rated operating voltage <em>U</em><sub>n</sub></td><td>110-240 VAC, 50/60 Hz</td></tr><tr><td>Max Switching Load (Resistive)</td><td>16 A</td></tr><tr><td>Type of switching</td><td>Relay, Micro gap (μ)</td></tr><tr><td>Over-voltage category</td><td>II</td></tr><tr><td>Rated insolating voltage <em>U</em><sub>i</sub></td><td>250V</td></tr><tr><td>Rated impulse withstand voltage <em>U</em>imp</td><td>2.5kV</td></tr><tr><td>Pollution degree</td><td>3</td></tr><tr><td>Protection degree</td><td>IP20</td></tr><tr><td>Rated operating temperature</td><td>-20 to 40°C</td></tr><tr><td>Humidity</td><td>30% to 70% RH</td></tr><tr><td>Max. altitude</td><td>2000m / 6562 ft</td></tr><tr><td>Conductor cross section</td><td>24 to 14AWG / 0.2 to 2,5mm²</td></tr><tr><td>Conductor stripped length</td><td>6 to 7mm / 0.24 to 0.28in</td></tr><tr><td>Screw terminals max torque</td><td>0.4Nm / 3.5Ibin</td></tr><tr><td>Measurement accuracy</td><td>±2% (Active energy)</td></tr><tr><td>Maximum Power consumption</td><td>≤ 3VA</td></tr><tr><td>Size: Height x Width x Depth</td><td>38mm x 42mm x 16mm</td></tr><tr><td>Integrated communication option</td><td>BLE; Wi-Fi; Zigbee;</td></tr></tbody></table>

**Nominal Power of Typical Loads&#x20;**<sup>**1) 2)**</sup>

|                                                   |         |
| ------------------------------------------------- | ------- |
| Incandescent & halogen lamps                      | 2000 W  |
| LED lamps3)4)                                     | 600 W   |
| Fluorescent lamps                                 | 500 VA  |
| Inductive motors (e.g., fans, pumps, compressors) | 1000 VA |
| Resistive heaters (e.g., boilers, room heaters)   | 2500 W  |

**Remark:**\
1\) If you are unsure about the load type or its impact on the smart relay switch, please contact our technical support.

2\) Individual channel value based on 220–240 VAC power supply.

3\) Inrush current Ion ≤ 78 A / 5 ms

4\) Due to variations in lamp electronics and manufacturers, the maximum value of controllable lamps may vary.

***

### 4. Mechanical Outline

**Dimension:** Unit in mm

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fq00SD8ZRYd8aSJCFgf76%2Fimage.png?alt=media&amp;token=7578e643-fb3d-4a7f-a0ea-f2f9ef274627" alt="" width="563"><figcaption></figcaption></figure>

***

### 5. Electrical Installation&#x20;

#### Wiring Diagram

**⚠️ Safety Remarks:**

* The device must be associated with easily accessible upstream protective devices ‒ such as miniature circuit breakers (MCB).
* The device must be installed, operated, serviced, and maintained **ONLY** by qualified professionals.
* Please read the user guide carefully before installation for detailed wiring diagrams and safety precautions.

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Ff4DefsrsK1CctX762HdN%2FSRS01-1PM-Wiring_EN_V1.0_2602.jpg?alt=media&amp;token=807d6916-ba5a-43dd-9739-7b5de40a006a" alt="" width="285"><figcaption></figcaption></figure>

#### Installation Video

{% embed url="<https://youtu.be/aPDcaC5aleg>" %}

<br>

***

### 6. User Interface

#### Reset Button

Press and hold for 3–5 seconds to enter pairing mode.

#### LED Indicator<br>

{% tabs %}
{% tab title="Tuya WiFi " %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Device connected - the device is online and functioning normally with cloud connectivity.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect using saved network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Network connected, cloud unreachable - the device is connected to Wi-Fi/Zigbee, but failed to reach the cloud.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Fault alarm (overheat, overcurrent, or relay failure) - The device has detected a fault. Please check the wiring and the device.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fgjz0xceslVOF4qKWMqa0%2FRed-Flashing-at-1Hz.jpg?alt=media&amp;token=202171d9-496d-4264-9b50-a7ab0d175d0c">Red-Flashing-at-1Hz.jpg</a></td></tr></tbody></table>

{% endtab %}

{% tab title="Standard Zigbee 3.0" %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Zigbee connected, BLE disconnected – the device is connected to a Zigbee network while BLE is turned off or not connected.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect both BLE (if available) and Zigbee using saved settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>BLE connected(if available)  - the LED flashes at 1Hz whenever BLE is connected, regardless of Zigbee status.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>The device has detected a fault. Please check the wiring and power supply.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fgjz0xceslVOF4qKWMqa0%2FRed-Flashing-at-1Hz.jpg?alt=media&amp;token=202171d9-496d-4264-9b50-a7ab0d175d0c">Red-Flashing-at-1Hz.jpg</a></td></tr></tbody></table>
{% endtab %}
{% endtabs %}

***

### 7. System Integration

Products equipped with different communication SOC firmwares connect to different systems and cloud platforms. Users can select the appropriate version based on their specific application requirements.

{% tabs %}
{% tab title="Tuya WiFi " %}
The Tuya WiFi version can only be integrated into the Tuya Cloud using Tuya's encrypted MQTT communication. It cannot be integrated with any third-party cloud platforms, ecosystems, or gateways.

However, Tuya's Smart Life App is user-friendly and straightforward, making it ideal for entry-level smart home users who prefer simplicity and basic energy consumption monitoring.
{% endtab %}

{% tab title="Standard Zigbee 3.0" %}
The Standard Zigbee 3.0 version can seamlessly connects to third-party gateways. Thanks to the standardized application-layer integration of Zigbee 3.0, it is highly convenient and widely applicable for both residential and commercial building projects.
{% endtab %}
{% endtabs %}

***

### 8. Ordering Information

<table><thead><tr><th width="86.7777099609375">#</th><th width="176.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SRS01-P1TW</td><td>SRS01 1×16A, Tuya Wi-Fi</td></tr><tr><td>2</td><td>SRS01-P1SZ</td><td>SRS01 1×16A, Standard Zigbee</td></tr></tbody></table>

***

### 9. FAQ&#x20;

{% content-ref url="/pages/149DFxm5iomFCS9alhv5" %}
[FAQ](/faq/overview)
{% endcontent-ref %}

***

### 10. Troubleshooting

{% content-ref url="/pages/td5Nnli4rm9AAhvTaYLk" %}
[Troubleshooting](/troubleshooting/overview)
{% endcontent-ref %}

***

### 11. Printed Document

<table data-full-width="false"><thead><tr><th width="588.5555419921875">Document</th><th>Download</th></tr></thead><tbody><tr><td>Datasheet</td><td><a href="https://downloads.bituo-technik.com/Datasheet/SRS01-1PM_Datasheet_EN.pdf">⬇️ PDF</a></td></tr><tr><td>User Guide</td><td><a href="https://downloads.bituo-technik.com/User-Guide/SRS01-1PM_User-Guide_EN.pdf">⬇️ PDF</a></td></tr></tbody></table>

***

### 12. Explore More

<br>


# SRS01-2PM

{% hint style="info" %}
&#x20;**Applies to:** SRS01 2PM | **Hardware Revision:** V1.0+ | **Last Updated:** 2026-05-27
{% endhint %}

### 1.  Introduction

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FE1MKOV3ec3CrowAM3oJO%2FSRS01-2PM-45-Degree_EN_V1.0_2602.jpg?alt=media&amp;token=a872949e-a612-4242-bccd-1c94aa584b0c" alt="" width="239"><figcaption></figcaption></figure></div>

SRS01 2PM is a compact dual-channel relay switch featuring independent power monitoring and wireless connectivity. It allows real-time control and monitoring of two separate AC loads, making it suitable for dual-circuit automation scenarios.

#### Product Highlights

* **Mini Dual-Relay**: Ultra-compact (38×42×16mm) fits behind switches. Controls two independent circuits (10A/ch, 16A Total) without changing your original switch style.
* **Independent Monitoring**: Measures real-time power and energy for each channel separately, providing precise per-device data unlike common total-sum solutions.
* **2-Channel Control**: Compatible with both toggle and momentary switches. Independently control two loads via App or wall switch simultaneously without conflict.
* **Flexible Connectivity**: Available in 3 editions to match your needs: Tuya Wi-Fi (Easy App), Matter over Wi-Fi, or Open Wi-Fi <-> Standard Zigbee 3.0 Switchable.
* **Built-in Safety**: Equipped with over-temperature, over-current, and over-voltage protection to extend product lifespan and minimize failure risks.

#### Typical Applications

* Smart Lighting: Install behind the roof or wall switches

***

### 2. Part Description

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FiAShpMIo3JuNBf4vKArz%2Fimage.png?alt=media&amp;token=edd292e7-4f0d-4215-b97d-0636f168902b" alt="" width="563"><figcaption></figcaption></figure>

<table><thead><tr><th width="84.5555419921875">#</th><th width="279.3333740234375">Element</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>Terminal Block(Screw Terminal)</td><td>Wiring terminals for connecting Live, Neutral, and switch input wires</td></tr><tr><td>2</td><td>Reset button</td><td>Press the button 3~5 seconds to enter the pairing mode</td></tr><tr><td>3</td><td>LED</td><td>Shows device operation and network status through different flashing patterns <sup>1)</sup></td></tr><tr><td>4</td><td>Product model</td><td>Refer to the ‘Ordering Information’ section for product selection</td></tr></tbody></table>

Remark:

1\) Refer to the user guide of your selected models for detailed LED status indicators.

***

### 3. Technical Data

| Parameter                                | Specification                    |
| ---------------------------------------- | -------------------------------- |
| Rated operating voltage *U*<sub>n</sub>  | 110-240 VAC, 50/60 Hz            |
| Max Switching Load (Resistive)           | 10 A per channel, max 16 A total |
| Type of switching                        | Relay, Micro gap (μ)             |
| Over-voltage category                    | II                               |
| Rated insolating voltage *U*<sub>i</sub> | 250V                             |
| Rated impulse withstand voltage *U*imp   | 2.5kV                            |
| Pollution degree                         | 3                                |
| Protection degree                        | IP20                             |
| Rated operating temperature              | -20 to 40°C                      |
| Humidity                                 | 30% to 70% RH                    |
| Max. altitude                            | 2000m / 6562 ft                  |
| Conductor cross section                  | 24 to 14AWG / 0.2 to 2,5mm²      |
| Conductor stripped length                | 6 to 7mm / 0.24 to 0.28in        |
| Screw terminals max torque               | 0.4Nm / 3.5Ibin                  |
| Measurement accuracy                     | ±2% (Active energy)              |
| Maximum Power consumption                | ≤ 3VA                            |
| Size: Height x Width x Depth             | 38mm x 42mm x 16mm               |
| Integrated communication option          | BLE; Wi-Fi; Zigbee;              |

**Nominal Power of Typical Loads&#x20;**<sup>**1) 2)**</sup>

|                              |        |
| ---------------------------- | ------ |
| Incandescent & halogen lamps | 800 W  |
| LED lamps3)4)                | 240 W  |
| Fluorescent lamps            | 200 VA |

**Remark:**\
1\) If you are unsure about the load type or its impact on the smart relay switch, please contact our technical support.

2\) Individual channel value based on 220–240 VAC power supply.

3\) Inrush current Ion ≤ 32 A / 5 ms

4\) Due to variations in lamp electronics and manufacturers, the maximum value of controllable lamps may vary.

***

### 4. Mechanical Outline

**Dimension:** Unit in mm

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fq00SD8ZRYd8aSJCFgf76%2Fimage.png?alt=media&amp;token=7578e643-fb3d-4a7f-a0ea-f2f9ef274627" alt="" width="563"><figcaption></figcaption></figure>

### 5. Electrical Installation&#x20;

#### Wiring Diagram

**⚠️ Safety Remarks:**

* The device must be associated with easily accessible upstream protective devices ‒ such as miniature circuit breakers (MCB).
* The device must be installed, operated, serviced, and maintained **ONLY** by qualified professionals.
* Please read the user guide carefully before installation for detailed wiring diagrams and safety precautions.

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FvYMmzj0VXtDI2NlCVg86%2FSRS01-2PM-Wiring-Webpage-300k-limit_EN_V1.0_2602.jpg?alt=media&amp;token=18c6937b-e042-4afb-a49e-89a6f310c5ae" alt=""><figcaption></figcaption></figure>

#### Installation Video

{% embed url="<https://youtu.be/hoEhraUdQIY>" %}

***

### 6. User Interface

#### Reset Button

Press and hold for 3–5 seconds to enter pairing mode.

#### LED Indicator

{% tabs %}
{% tab title="Tuya WiFi " %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Device connected - the device is online and functioning normally with cloud connectivity.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect using saved network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Network connected, cloud unreachable - the device is connected to Wi-Fi/Zigbee, but failed to reach the cloud.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>Fault alarm (overheat, overcurrent, or relay failure) - The device has detected a fault. Please check the wiring and the device.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fgjz0xceslVOF4qKWMqa0%2FRed-Flashing-at-1Hz.jpg?alt=media&amp;token=202171d9-496d-4264-9b50-a7ab0d175d0c">Red-Flashing-at-1Hz.jpg</a></td></tr></tbody></table>

{% endtab %}

{% tab title="Standard Zigbee 3.0" %}

<table data-view="cards"><thead><tr><th></th><th></th><th data-hidden data-card-cover data-type="image">Cover image</th></tr></thead><tbody><tr><td><strong>Solid ON</strong></td><td>Zigbee connected, BLE disconnected – the device is connected to a Zigbee network while BLE is turned off or not connected.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FkwU3dFE15wPbfD9F0pNa%2FGreen-Solid.jpg?alt=media&amp;token=25208946-1df1-4614-b704-4517fd007118">Green-Solid.jpg</a></td></tr><tr><td><strong>Flashing at 2Hz</strong></td><td>Pairing mode – press and hold the reset button until the LED flashes rapidly.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FWbizEiq4JMS3j9XhBsxE%2FGreen-Flashing-at-2Hz.jpg?alt=media&amp;token=bf22526a-6206-4d63-85c2-bba85ba1ae3b">Green-Flashing-at-2Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.5Hz</strong></td><td>Reconnecting to network - the device is attempting to reconnect both BLE (if available) and Zigbee using saved settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FScRpvSt4h8Am2wmcoKxd%2FGreen-Flashing-at-0.5Hz.jpg?alt=media&amp;token=8c349252-fdd8-4395-85a7-db01b7558cdf">Green-Flashing-at-0.5Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>BLE connected(if available)  - the LED flashes at 1Hz whenever BLE is connected, regardless of Zigbee status.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKX5vs26feuR7YXnc2kTE%2FGreen-Flashing-at-1Hz.jpg?alt=media&amp;token=2153be0f-7635-4f9e-a44e-7064b0dc2f12">Green-Flashing-at-1Hz.jpg</a></td></tr><tr><td><strong>Flashing at 0.25Hz</strong></td><td>The device failed internal self-check. Please power off, restart, and reconfigure the network settings.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOZwF7G2PEbBtuaDzEYfW%2FGreen-Flashing-at-0.25Hz.jpg?alt=media&amp;token=82a8f1f8-d5e9-44b7-97df-7fd9cee4af83">Green-Flashing-at-0.25Hz.jpg</a></td></tr><tr><td><strong>Flashing at 1Hz</strong></td><td>The device has detected a fault. Please check the wiring and power supply.</td><td data-object-fit="contain"><a href="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fgjz0xceslVOF4qKWMqa0%2FRed-Flashing-at-1Hz.jpg?alt=media&amp;token=202171d9-496d-4264-9b50-a7ab0d175d0c">Red-Flashing-at-1Hz.jpg</a></td></tr></tbody></table>
{% endtab %}
{% endtabs %}

***

### 7. System Integration

Products equipped with different communication SOC firmwares connect to different systems and cloud platforms. Users can select the appropriate version based on their specific application requirements.

{% tabs %}
{% tab title="Tuya WiFi " %}
The Tuya WiFi version can only be integrated into the Tuya Cloud using Tuya's encrypted MQTT communication. It cannot be integrated with any third-party cloud platforms, ecosystems, or gateways.

However, Tuya's Smart Life App is user-friendly and straightforward, making it ideal for entry-level smart home users who prefer simplicity and basic energy consumption monitoring.
{% endtab %}

{% tab title="Standard Zigbee 3.0" %}
The Standard Zigbee 3.0 version can seamlessly connects to third-party gateways. Thanks to the standardized application-layer integration of Zigbee 3.0, it is highly convenient and widely applicable for both residential and commercial building projects.
{% endtab %}
{% endtabs %}

***

### 8. Ordering Information

<table><thead><tr><th width="86.7777099609375">#</th><th width="176.6666259765625">Ordering number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SRS01-P2TW</td><td>SRS01 2×10A, Tuya Wi-Fi</td></tr><tr><td>2</td><td>SRS01-P2SZ</td><td>SRS01 2×10A, Standard Zigbee</td></tr></tbody></table>

***

### 9. FAQ&#x20;

{% content-ref url="/pages/149DFxm5iomFCS9alhv5" %}
[FAQ](/faq/overview)
{% endcontent-ref %}

***

### 10. Troubleshooting

{% content-ref url="/pages/td5Nnli4rm9AAhvTaYLk" %}
[Troubleshooting](/troubleshooting/overview)
{% endcontent-ref %}

***

### 11. Printed Document

<table data-full-width="false"><thead><tr><th width="588.5555419921875">Document</th><th>Download</th></tr></thead><tbody><tr><td>Datasheet</td><td><a href="https://downloads.bituo-technik.com/Datasheet/SRS01-1PM_Datasheet_EN.pdf">⬇️ PDF</a></td></tr><tr><td>User Guide</td><td><a href="https://downloads.bituo-technik.com/User-Guide/SRS01-2PM_User-Guide_EN.pdf">⬇️ PDF</a></td></tr></tbody></table>

***

### 12. Explore More

\ <br>


# BRCS Series

## BRCS Series — AC/DC Residual Current Sensors for EV Charging

Built-in AC/DC residual current sensors designed for Mode-2 and Mode-3 EV charging equipment (AC EV Chargers). Detects both smooth DC and AC residual currents, with digital output signals for direct integration into EVSE control circuits.

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FpFU3jcpXBGipgeEvrZV2%2FBRCSFamily-04.jpg?alt=media&amp;token=4c54d0f1-b12d-4377-8757-f42cc1283cde" alt=""><figcaption></figcaption></figure>

***

### Product Variants

\
BRCS products are defined across **three dimensions**:

#### **1. Form Factor**&#x20;

Following the release of IEC 62955 in 2018, we obtained the world's first TÜV-certified RDC-MD and RDC-PD certificates in 2019. Through the large-scale application of millions of units over the past few years, we have continuously optimized our product line. Our current mainstream product lines are as follows:

| Model             | BRCS01C                                                                                                                                                                                                                                                 | BRCS03C                                                                                                                                                                                                                                                 | BRCS03X                                                                                                                                                                                                                                                 | BRCS01V                                                                                                                                                                                                                                                 |
| ----------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| Image             | <img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FedRbWUOfZZqkSdWMekjt%2Fimage.png?alt=media&amp;token=0896967b-66b0-41ec-a828-cc76ec3df95d" alt="" data-size="original"> | <img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FT4oJRipNGMhQxZ1JYGNq%2Fimage.png?alt=media&amp;token=e9725707-a579-496f-830e-1fe8960cfd84" alt="" data-size="original"> | <img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FPTBgtms70aIQ1f2lT6Sc%2Fimage.png?alt=media&amp;token=af8335c8-1b07-42c6-b9ea-9f1395f80a05" alt="" data-size="original"> | <img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FXhGCjh26qhZ7E2hq8TeX%2Fimage.png?alt=media&amp;token=6c8fafb9-fe73-4989-a54e-5461e5cfe7d0" alt="" data-size="original"> |
| **Mounting Type** | Cable-mounting / PCB-mounting/ Enclosure-mounting                                                                                                                                                                                                       | PCB-mounting (Copper jumper)                                                                                                                                                                                                                            | PCB-mounting (Horizontal Through hole)                                                                                                                                                                                                                  | PCB-mounting (Vertical Through hole)                                                                                                                                                                                                                    |

> 💡 **BRCS01C** is the only platform offering a **12V supply variant** (`-12-H1`), which is ideal for users who prefer not to process fault signals through an MCU and require indicator lights for easy on-site troubleshooting.&#x20;

#### **2. Compliance Standard**

Every form factor is available in both IEC and UL versions. In other words, IEC and UL versions share the same hardware form factor but have **different pin assignments and output logic**. Always select the correct compliance version for your target market.

|                               | IEC Version                                                    | UL Version                                                |
| ----------------------------- | -------------------------------------------------------------- | --------------------------------------------------------- |
| **Target Market**             | Europe, Asia, and global IEC markets                           | North America (UL/CCID20 required)                        |
| **Fault Signal Output Pin-A** | DC-only fault signal (RDC-MD, IEC 62955 DC 6 mA)               | IEC 62955 fault signal (RDC-MD) **or** IEC 62752 (IC-CPD) |
| **Fault Signal Output Pin-B** | AC & DC fault signal (RDC-PD / IC-CPD, Type-A 30 mA + DC 6 mA) | UL 2231-2 fault signal (X20, CCID20, AC 20 mA)            |
| **Applicable Standards**      | IEC 62955, IEC 62752, IEC 60947-2-(M)                          | UL 2231-2 (CCID20) + IEC 62955 / IEC 62752                |

#### **3. Supply Chain Compatibility:**&#x20;

Thoughtfully designed pinouts and form factors ensure seamless drop-in replacement and supply chain security for EV charger manufacturers.

* The **BRCS01C-12V** version is fully pin-compatible with the Littelfuse RCM14/20 series (formerly Western Automation).
* The **BRCS03C** and **BRCS03X** series are highly compatible with the BENVAC N4641 series. Although our sensors utilize a 6-pin interface compared to BENVAC's 8-pin design, users can achieve seamless compatibility on the same charging controller hardware through automatic firmware adaptation.

> **Our Philosophy on Compatibility:** Compatibility is fundamentally about delivering value to the customer. Consider DIN-rail mounted circuit breakers: while their internal technologies vary, their standardized external form factor provides immense convenience to users and drives healthy market development. We apply this same standardization philosophy to our sensor designs to simplify integration for our customers.

<table><thead><tr><th width="218">Our Model</th><th>Compatible</th></tr></thead><tbody><tr><td><a href="/product-document/brcs-series/brcs03c-iec">BRCS03C-05-L1</a></td><td><a href="https://vacuumschmelze.com/products/current-sensors/benvac">N4641-X820</a></td></tr><tr><td><a href="/product-document/brcs-series/brcs03c-ul">BRCS03C-U5-L1</a></td><td><a href="https://vacuumschmelze.com/products/current-sensors/benvac">N4641-X825</a></td></tr><tr><td><a href="/product-document/brcs-series/brcs03c-ul">BRCS03C-U6-L1</a></td><td>N.A</td></tr><tr><td><a href="/product-document/brcs-series/brcs03x-iec">BRCS03X-05-L2</a></td><td><a href="https://vacuumschmelze.com/products/current-sensors/benvac">N4641-X805</a></td></tr><tr><td><a href="/product-document/brcs-series/brcs03x-ul">BRCS03X-U5-L2</a></td><td><a href="https://vacuumschmelze.com/products/current-sensors/benvac">N4641-X804</a></td></tr><tr><td><a href="/product-document/brcs-series/brcs03x-ul">BRCS03X-U6-L2</a></td><td>N.A.</td></tr><tr><td><a href="/product-document/brcs-series/brcs01c-iec">BRCS01C-12-H1</a></td><td><a href="https://www.littelfuse.com/products/sensors/current-sensors/residual-current-protection/mode-3-ev-charger-monitors/rcm14-01">RCM14-01</a>, <a href="https://www.littelfuse.com/products/sensors/current-sensors/residual-current-protection/mode-2-ev-charger-monitors/rcm14-03">RCM14-03</a>, <a href="https://www.littelfuse.com/products/sensors/current-sensors/residual-current-protection/mode-3-ev-charger-monitors/rcm20-01">RCM20-01</a>, <a href="https://www.littelfuse.com/products/sensors/current-sensors/residual-current-protection/mode-2-ev-charger-monitors/rcm20-03">RCM20-03</a></td></tr></tbody></table>

### Model List&#x20;

<table><thead><tr><th width="163">Model</th><th width="104">Image</th><th width="149.5555419921875">Residual Current Type</th><th width="277">Pin Interface</th><th width="115.77783203125">Datasheet</th></tr></thead><tbody><tr><td><strong>BRCS01C-05-H1</strong></td><td><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FedRbWUOfZZqkSdWMekjt%2Fimage.png?alt=media&amp;token=0896967b-66b0-41ec-a828-cc76ec3df95d" alt="" data-size="original"></td><td>Type A 30mA+DC6mA and DC6mA</td><td>6 pin – VCC(5V), AC&#x26;DC TRIP, GND, CAL, TEST, DC TRIP</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BRCS01C-IEC_Datasheet_EN.pdf">📥</a></td></tr><tr><td><strong>BRCS01C-12-H1</strong></td><td><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FedRbWUOfZZqkSdWMekjt%2Fimage.png?alt=media&amp;token=0896967b-66b0-41ec-a828-cc76ec3df95d" alt=""></td><td>Type A 30mA+DC6mA and DC6mA</td><td>6 pin – GND, VCC(12V), TEST, DC TRIP, AC&#x26;DC TRIP, NC</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BRCS01C-IEC_Datasheet_EN.pdf">📥</a></td></tr><tr><td><strong>BRCS01C-U5-H1</strong></td><td><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FedRbWUOfZZqkSdWMekjt%2Fimage.png?alt=media&amp;token=0896967b-66b0-41ec-a828-cc76ec3df95d" alt=""></td><td>CCID20 and DC6mA</td><td>6 pin – VCC(5V), CCID20 TRIP, GND, CAL, TEST, DC TRIP</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BRCS01C-UL_Datasheet_EN.pdf">📥 </a></td></tr><tr><td><strong>BRCS01C-U6-H1</strong></td><td><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FedRbWUOfZZqkSdWMekjt%2Fimage.png?alt=media&amp;token=0896967b-66b0-41ec-a828-cc76ec3df95d" alt=""></td><td>CCID20 and Type A 30mA+DC6mA</td><td>6 pin – VCC(5V), CCID20 TRIP, GND, CAL, TEST, AC&#x26;DC TRIP</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BRCS01C-UL_Datasheet_EN.pdf">📥 </a></td></tr><tr><td><strong>BRCS01V-05-S1</strong></td><td><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FXhGCjh26qhZ7E2hq8TeX%2Fimage.png?alt=media&amp;token=6c8fafb9-fe73-4989-a54e-5461e5cfe7d0" alt=""></td><td>Type A 30mA+DC 6mA</td><td>5 PIN – VCC, AC&#x26;DC TRIP, GND, DC Trip, TEST</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BRCS01V-IEC_Datasheet_EN.pdf">📥</a> </td></tr><tr><td><strong>BRCS01V-U5-S1</strong></td><td><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FXhGCjh26qhZ7E2hq8TeX%2Fimage.png?alt=media&amp;token=6c8fafb9-fe73-4989-a54e-5461e5cfe7d0" alt=""></td><td>CCID20 and DC6mA</td><td>5 PIN – VCC, CCID20 TRIP, GND, DC Trip, TEST</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BRCS01V-UL_Datasheet_EN.pdf">📥 </a></td></tr><tr><td><strong>BRCS01V-U6-S1</strong></td><td><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FXhGCjh26qhZ7E2hq8TeX%2Fimage.png?alt=media&amp;token=6c8fafb9-fe73-4989-a54e-5461e5cfe7d0" alt=""></td><td>CCID20 and Type A 30mA+DC6mA</td><td>5 PIN – VCC, CCID20 TRIP, GND, AC&#x26;DC Trip, TEST</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BRCS01V-UL_Datasheet_EN.pdf">📥 </a></td></tr><tr><td><strong>BRCS03C-05-L1</strong></td><td><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FT4oJRipNGMhQxZ1JYGNq%2Fimage.png?alt=media&amp;token=e9725707-a579-496f-830e-1fe8960cfd84" alt=""></td><td>Type A 30mA+DC6mA and DC6mA</td><td>6 PIN – NC, TEST, DC TRIP, AC&#x26;DC TRIP, GND, 5V DC</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BRCS03C-IEC_Datasheet_EN.pdf">📥 </a></td></tr><tr><td><strong>BRCS03C-U5-L1</strong></td><td><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FT4oJRipNGMhQxZ1JYGNq%2Fimage.png?alt=media&amp;token=e9725707-a579-496f-830e-1fe8960cfd84" alt="" data-size="original"></td><td>CCID20 and DC6mA</td><td>6 PIN – NC, TEST, DC TRIP, CCID20 TRIP, GND, 5V DC</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BRCS03C-UL_Datasheet_EN.pdf">📥 </a></td></tr><tr><td><strong>BRCS03C-U6-L1</strong></td><td><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FT4oJRipNGMhQxZ1JYGNq%2Fimage.png?alt=media&amp;token=e9725707-a579-496f-830e-1fe8960cfd84" alt=""></td><td>CCID20 and Type A 30mA+DC6mA</td><td>6 PIN – NC, TEST, AC&#x26;DC TRIP, CCID20 TRIP, GND, 5V DC</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BRCS03C-UL_Datasheet_EN.pdf">📥 </a></td></tr><tr><td><strong>BRCS03X-05-L2</strong></td><td><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FPTBgtms70aIQ1f2lT6Sc%2Fimage.png?alt=media&amp;token=af8335c8-1b07-42c6-b9ea-9f1395f80a05" alt=""></td><td>Type A 30mA+DC6mA and DC6mA</td><td>6 PIN – NC, TEST, DC TRIP, AC&#x26;DC TRIP, GND, 5V DC</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BRCS03X-IEC_Datasheet_EN.pdf">📥 </a></td></tr><tr><td><strong>BRCS03X-U5-L2</strong></td><td><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FPTBgtms70aIQ1f2lT6Sc%2Fimage.png?alt=media&amp;token=af8335c8-1b07-42c6-b9ea-9f1395f80a05" alt=""></td><td>CCID20 and DC6mA</td><td>6 PIN – NC, TEST, DC TRIP, CCID20 TRIP, GND, 5V DC</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BRCS03X-UL_Datasheet_EN.pdf">📥 </a></td></tr><tr><td><strong>BRCS03X-U6-L2</strong></td><td><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FPTBgtms70aIQ1f2lT6Sc%2Fimage.png?alt=media&amp;token=af8335c8-1b07-42c6-b9ea-9f1395f80a05" alt=""></td><td>CCID20 and Type A 30mA+DC6mA</td><td>6 PIN – NC, TEST, AC&#x26;DC TRIP, CCID20 TRIP, GND, 5V DC</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BRCS03X-UL_Datasheet_EN.pdf">📥 </a></td></tr><tr><td><strong>BRCS01-ADC-L</strong></td><td><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FuEf2CGrfTTVueZ3bhyr3%2Fimage.png?alt=media&amp;token=cd206782-93c1-44ee-be4d-25641dc30a18" alt="" data-size="original"></td><td>Type A 30mA+DC6mA </td><td>4 PIN – 5V, GND, TEST, AC&#x26;DC TRIP</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BRCS01_Datasheet_EN.pdf">📥 </a></td></tr><tr><td><strong>BRCS01-DC6-L</strong></td><td><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FuEf2CGrfTTVueZ3bhyr3%2Fimage.png?alt=media&amp;token=cd206782-93c1-44ee-be4d-25641dc30a18" alt=""></td><td>DC6mA</td><td>4 PIN – 5V, GND, TEST, DC TRIP</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BRCS01_Datasheet_EN.pdf">📥 </a></td></tr></tbody></table>

*Please click here to view discontinued and not-recommended-for-new-design (NRND) products.*


# BRCS01C - IEC

## BRCS01C - IEC

{% hint style="info" %}
**Applies to:** BRCS01C AC/DC Residual Current Sensor (IEC version, Type A 30mA and DC 6mA (IEC 62752; IEC 62955) / DC 6mA (IEC 62955)) | **Last Updated:** 2026-09-28
{% endhint %}

### 1. Introduction

![](https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FTFOcTJp8l3cmvE2XUN52%2FBRCS01C.png?alt=media\&token=edb90b54-31fe-4c32-ae30-a797e7cf96cc)

The BRCS01C is an AC/DC residual current sensor with two separate fault signal outputs – one Pin for type-A 30mA + DC 6mA residual current detection (RDC-PD application) and the other Pin for DC 6mA residual current detection (RDC-MD application). It can be used for built-in residual current protection at AC charging system.

* 5V DC or 12V DC interfaces available to meet different design practices
* Two fault signal pins for solely DC 6mA and Type-A 30mA +DC 6mA alarming
* Cost-effective solution of built-in residual current device for AC EV charger
* Fast response time facilitating a broad selection of switching devices
* Compact design with 17mm through-hole for charging cable up to 3P+N 32A

***

### 2. Technical Data

<table><thead><tr><th width="58">#</th><th width="320">Technical Specification</th><th>BRCS01C-05-H1</th><th>BRCS01C-12-H1</th></tr></thead><tbody><tr><td>101</td><td>Rated operating voltage in monitoring circuit</td><td>230/400VAC</td><td>230/400VAC</td></tr><tr><td>102</td><td>Rated current in monitoring circuit</td><td>≤ 32A</td><td>≤ 32A</td></tr><tr><td>103</td><td>Poles in monitoring circuit</td><td>1P+N / 3P+N</td><td>1P+N / 3P+N</td></tr><tr><td>104</td><td>Frequency in monitoring circuit</td><td>50Hz</td><td>50Hz</td></tr><tr><td>105</td><td>Rated impulse withstand voltage in monitoring circuit</td><td>6kV</td><td>6kV</td></tr><tr><td>106</td><td>Over-voltage category in monitoring circuit</td><td>III</td><td>III</td></tr><tr><td>201</td><td>Rated operating voltage in control circuit, <span class="math">V_{cc}</span></td><td>5VDC ± 3%</td><td>12VDC ± 20%</td></tr><tr><td>202</td><td>Power consumption</td><td>&#x3C; 500mW</td><td>&#x3C; 500mW</td></tr><tr><td>203</td><td>Pin 1</td><td>Vcc 5VDC</td><td>GND</td></tr><tr><td>204</td><td>Pin 2</td><td>AC &#x26; DC Trip</td><td>+12VDC</td></tr><tr><td>205</td><td>Pin 3</td><td>GND</td><td>Test</td></tr><tr><td>206</td><td>Pin 4</td><td>CAL</td><td>DC Trip</td></tr><tr><td>207</td><td>Pin 5</td><td>Test</td><td>AC &#x26; DC Trip</td></tr><tr><td>208</td><td>Pin 6</td><td>DC Trip</td><td>-</td></tr><tr><td>301</td><td>Rated DC residual operating current <span class="math">I_{\Delta dc}</span></td><td>6mA</td><td>6mA</td></tr><tr><td>302</td><td>Rated DC residual non-operating current <span class="math">I_{\Delta ndc}</span></td><td>3mA</td><td>3mA</td></tr><tr><td>303</td><td>Rated AC residual operating current <span class="math">I_{\Delta n}</span> <sup>1)</sup></td><td>30mA</td><td>30mA</td></tr><tr><td>304</td><td>Rated AC residual non-operating current <span class="math">I_{\Delta nc}</span> <sup>1)</sup></td><td>15mA</td><td>15mA</td></tr><tr><td>305</td><td>Electrical endurance</td><td>20,000</td><td>20,000</td></tr><tr><td>306</td><td>Rated operating temperature</td><td>-40~85 ℃</td><td>-40~85 ℃</td></tr><tr><td>307</td><td>Pollution degree</td><td>2</td><td>2</td></tr></tbody></table>

> *1) #303 and #304 apply to only the AC\&DC Trip Pin that sends fault output of Type-A 30mA detection.*

***

### 3. Residual Current Detection Characteristics

#### **Operating Current**

<table><thead><tr><th width="81">#</th><th width="428.333251953125">Description</th><th>AC&#x26;DC trip signal</th><th>DC trip signal</th></tr></thead><tbody><tr><td>401</td><td>Operating current for smooth DC</td><td>4.0~6.0 mA</td><td>4.0~6.0 mA</td></tr><tr><td>402</td><td>Operating current for DC rectified from 2 phases</td><td>4.0~7.0 mA</td><td>4.0~7.0 mA</td></tr><tr><td>403</td><td>Operating current for DC rectified from 3 phases</td><td>4.0~6.2 mA</td><td>4.0~6.2 mA</td></tr><tr><td>404</td><td>Operating current for sinewave AC</td><td>22.0~28.0 mA</td><td>-</td></tr><tr><td>405</td><td>Operating current for A0 pulsating DC</td><td>10.5~42.0 mA</td><td>-</td></tr><tr><td>406</td><td>Operating current for A90 pulsating DC</td><td>7.5~42.0 mA</td><td>-</td></tr><tr><td>407</td><td>Operating current for A135 pulsating DC</td><td>3.3~42.0 mA</td><td>-</td></tr></tbody></table>

#### **Operating Time**

<table><thead><tr><th width="82">#</th><th width="433.888916015625">Description</th><th>AC&#x26;DC trip signal</th><th>DC trip signal</th></tr></thead><tbody><tr><td>501</td><td>Response time for 6mA smooth DC residual current</td><td>≤ 500 ms</td><td>≤ 500 ms</td></tr><tr><td>502</td><td>Response time for 60mA smooth DC residual current</td><td>≤ 200 ms</td><td>≤ 200 ms</td></tr><tr><td>503</td><td>Response time for 200mA smooth DC residual current</td><td>≤ 70 ms</td><td>≤ 70 ms</td></tr><tr><td>504</td><td>Response time for 300mA smooth DC residual current</td><td>≤ 20 ms</td><td>-</td></tr><tr><td>505</td><td>Response time for 60mA DC rectified from 2 phases</td><td>≤ 200 ms</td><td>≤ 200 ms</td></tr><tr><td>506</td><td>Response time for 200mA DC rectified from 2 phases</td><td>≤ 70 ms</td><td>≤ 70 ms</td></tr><tr><td>507</td><td>Response time for 300mA DC rectified from 2 phases</td><td>≤ 20 ms</td><td>-</td></tr><tr><td>508</td><td>Response time for 60mA DC rectified from 3 phases</td><td>≤ 200 ms</td><td>≤ 200 ms</td></tr><tr><td>509</td><td>Response time for 200mA DC rectified from 3 phases</td><td>≤ 70 ms</td><td>≤ 70 ms</td></tr><tr><td>510</td><td>Response time for 300mA DC rectified from 3 phases</td><td>≤ 20 ms</td><td>-</td></tr><tr><td>511</td><td>Response time for 30mA AC residual current</td><td>≤ 80 ms</td><td>> 10000 ms</td></tr><tr><td>512</td><td>Response time for 60mA AC residual current</td><td>≤ 60 ms</td><td>> 300 ms</td></tr><tr><td>513</td><td>Response time for 150mA AC residual current</td><td>≤ 20 ms</td><td>> 80 ms</td></tr><tr><td>514</td><td>Response time for 5A AC residual current</td><td>≤ 20 ms</td><td>> 80 ms</td></tr></tbody></table>

***

### 4. Application Notes&#x20;

{% tabs %}
{% tab title="12V DC Version" %}

#### **Typical application diagram**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FBO4FQQvSqOFJNkgYwj4b%2Fimage.png?alt=media&amp;token=2dbe16b7-73e4-4135-8c9a-a2f118ddf6af" alt=""><figcaption></figcaption></figure>

Additional information

* **Attention:** A Mosfet is built in the 12V DC sensor to switch the connection to signal V- as normal using. The maximum switching current of the 12V DC sensor is **500mA**.
* **Attention:** Pin 6 is only for internal use by the sensor. It shall be kept floating (not connected).

#### **Self-test time chart**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FnlK9bFbHZADCrsIK4zje%2Fimage.png?alt=media&amp;token=c5b9744a-288c-4133-b619-c442f423a3a0" alt=""><figcaption></figcaption></figure>

A self-test excluding offset calibration is activated if Pin 3 - Test is connected to a high level for a period of **40ms to 1000ms**. *(Note:* $$t\_1$$ *is the response time for internally generated test current.)*

#### **Offset calibration time chart**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fn9apXI1J55cerlhJrlx5%2Fimage.png?alt=media&amp;token=4c68dd0c-c1e1-4b79-864e-d313ad0524f8" alt=""><figcaption></figcaption></figure>

An offset calibration is activated if Pin 3 - Test is connected to a high level for a period of **4.5s ± 5%**. An offset calibration can be activated at regular intervals (such as startup) or after the occur of certain critical events (such as short circuit).

> ⚠️ **Attention**: During the offset calibration, **NO leakage current or any other current may flow through the sensor** and the switching devices must be open. Also, the power supply voltage at Pin 2 Vcc must be stay at **12VDC ± 20%**.

#### **Possible Output States (12V Version)**

| Status                                                             | PIN 4 Output (DC Trip) | PIN 5 Output (AC & DC Trip) |
| ------------------------------------------------------------------ | ---------------------- | --------------------------- |
| **Normal condition**                                               | GND                    | GND                         |
| $$I\_{\Delta} \ge 6$$ **mA DC**                                    | High impedance         | High impedance              |
| $$I\_{\Delta} \ge 30$$ **mA AC**                                   | GND *1)*               | High impedance              |
| $$I\_{\Delta} \ge 30$$ **mA AC &** $$I\_{\Delta} \ge 6$$ **mA DC** | High impedance         | High impedance              |

> *1) A change from GND to High impedance is allowed, if such a change is compliant with IEC 62955.*
> {% endtab %}

{% tab title="5V DC Version" %}

#### **Typical application diagram**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FsduWtmCLAk9AEoyXVTbT%2Fimage.png?alt=media&amp;token=d6e8eeb6-d3ad-429a-b236-da17e7d4cc31" alt=""><figcaption></figcaption></figure>

Additional information

* **Attention:** A direct connection of Pin 2/6 to switching devices such as relays or contactors - is **NOT allowed**. The trip signal of Pin2/6 is suggested to be monitored by the charging controller MCU.

#### **Self-test time chart**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2F5KdsAgkujwtnkvHGj2Z7%2Fimage.png?alt=media&amp;token=955f7d33-81e2-4dcf-b958-20535b1df9ea" alt=""><figcaption></figcaption></figure>

A self-test excluding offset calibration is activated if Pin 5 - Test is connected to a high level for a period **above 40ms**. *(Note:* $$t\_1$$ *is the response time for internally generated test current.)*

#### **Offset calibration time chart**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FYFuhEuQARlAzxqxKlImL%2Fimage.png?alt=media&amp;token=0b7a70b2-bad8-43be-a4f8-e108cd86ed6f" alt=""><figcaption></figcaption></figure>

An offset calibration is activated if Pin 4 - CAL is connected to GND for a period between **50ms and 100ms**. An offset calibration can be activated at regular intervals (such as start-up) or after the occur of certain critical events (such as short circuit).

> ⚠️ **Attention**: During the offset calibration, **NO leakage current or any other current may flow through the device** and the relays/contactors must be open. Also, the power supply voltage at Pin 1 Vcc must be stay at **5VDC ± 3%**.

#### **Possible Output States (5V Version)**

<table><thead><tr><th width="303.888916015625">Status</th><th>PIN 2 Output (AC &#x26; DC Trip)</th><th>PIN 6 Output (DC Trip)</th></tr></thead><tbody><tr><td>Normal condition</td><td>GND</td><td>GND</td></tr><tr><td><span class="math">I_{\Delta} \ge 6</span> mA DC</td><td>High level</td><td>High level</td></tr><tr><td><span class="math">I_{\Delta} \ge 6</span> mA DC</td><td>High level</td><td>GND <em>1)</em></td></tr><tr><td><span class="math">I_{\Delta} \ge 30</span> mA AC &#x26; <span class="math">I_{\Delta} \ge 6</span> mA DC</td><td>High level</td><td>High level</td></tr></tbody></table>

> *1) A change from GND to High level is allowed, as long as such a change is compliant with IEC 62955.*
> {% endtab %}
> {% endtabs %}

***

### 5. Mechanical outline

#### **BRCS01C-05-H1 / BRCS01C-12-H1:**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FHvbfMjByutgkTiF9dDQE%2Fimage.png?alt=media&amp;token=b105c767-fad6-4e68-9914-1ff8699179ed" alt=""><figcaption></figcaption></figure>

<table><thead><tr><th width="154.666748046875">Version</th><th width="88">Pin 1</th><th width="98">Pin 2</th><th width="96.888916015625">Pin 3</th><th width="100.22216796875">Pin 4</th><th width="94.6666259765625">Pin 5</th><th width="105.77783203125">Pin 6</th></tr></thead><tbody><tr><td><strong>BRCS01C-05-*</strong></td><td>5V DC</td><td>AC &#x26; DC Trip</td><td>GND</td><td>CAL</td><td>Test</td><td>DC Trip</td></tr><tr><td><strong>BRCS01C-12-*</strong></td><td>GND</td><td>+12V DC</td><td>TEST</td><td>DC Trip</td><td>AC &#x26; DC Trip</td><td>NC</td></tr></tbody></table>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FtW0AXI5r1X6ZoLVhpSwl%2Fimage.png?alt=media&amp;token=4c2e7bbb-027e-4c3e-8feb-09d66c602da7" alt=""><figcaption></figcaption></figure>

***

### 6. Ordering information

<table><thead><tr><th width="65">#</th><th width="197">Order Number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td><strong>BRCS01C-05-H1</strong></td><td>BRCS01C Residual Current Sensor, 5V DC Interface, Flexible<br>Type A 30 mA+DC6mA / DC6mA, 32A, 1P+N / 3P+N</td></tr><tr><td>2</td><td><strong>BRCS01C-12-H1</strong></td><td>BRCS01C Residual Current Sensor, 12V DC Interface, Flexible<br>Type A 30 mA+DC6mA / DC6mA, 32A, 1P+N / 3P+N</td></tr><tr><td>3</td><td><strong>BCHY6HY6-N030</strong></td><td>300mm cable with 2×6PIN HY2.0 Connectors <sup>1) 2)</sup></td></tr></tbody></table>

> *1) BM6B-PASS (JST, SMT), BM6B-PASK (JST, DIP), A2012WV-S-6P (CJT, SMT) or A2012WV-6P (CJT, DIP) can be used at the charging controller side.*&#x20;
>
> *2) Specific customization requirements can be provided upon request.*

***

### 7. Additional Notes

> 🛑 **ESD Warning**: The sensor is susceptible to be damaged from an ESD event and the personnel should be grounded when handling it.

* Do **NOT** allow strong static electricity near the sensor, because static electricity can cause damage to the ICs inside the sensor. Take static electricity precautions when handling.
* Do **NOT** drop the sensor or apply any other mechanical stress to the sensor, as such stresses may change performance characteristics.
* Please place the sensor with an appropriate distance from components that can generate high magnetic fields, such as relays or contactors, to ensure accurate residual current detection.
* Please refer to the product standards of RCD/RDC-DD (Residual Current Device / Residual Direct Current Detection Device), when designing built-in RCD/RDC-DD for mode-2/3 Electric Vehicle Supply Equipment with the sensor.


# BRCS03C - IEC

{% hint style="info" %}
&#x20;**Applies to:** BRCS03C AC/DC Residual Current Sensor (IEC version, Type A 30mA and DC 6mA (IEC 60947-2+IEC 62955) / DC 6mA (IEC 62955)) | **Updated:** 2026-09-25
{% endhint %}

### 1. Introduction

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FT4oJRipNGMhQxZ1JYGNq%2Fimage.png?alt=media&amp;token=e9725707-a579-496f-830e-1fe8960cfd84" alt="" width="150"><figcaption></figcaption></figure></div>

The BRCS03C is an AC/DC residual current sensor with two separate fault signal outputs – one Pin with DC fault signal output and the other Pin with AC & DC fault signal output. It can be used for built-in RDC-MD (Residual Direct Current Monitoring Device, DC 6mA, IEC 62955) or RDC-PD (Type A 30mA and DC 6mA, Residual Direct Current Protection Device, IEC61008-1 + IEC 62955) at Mode-3 AC chargers. Additionally, it can be used in IC-CPD (In-Cable Control- and Protection Device).

* Accurate measurement and optimization against nuisance tripping
* Cost-effective solution of residual current detection for Mode-2/3 EVSE
* Fast response time facilitating a broad selection of switching devices
* Two fault signal pins for solely DC 6mA and Type-A 30mA +DC 6mA alarming

***

### 2. Technical Data

<table><thead><tr><th width="75">#</th><th width="415">Technical Specification</th><th>Value</th></tr></thead><tbody><tr><td>101</td><td>Rated operating voltage in monitoring circuit</td><td>230/400VAC</td></tr><tr><td>102</td><td>Rated current in monitoring circuit</td><td>≤ 32A</td></tr><tr><td>103</td><td>Poles in monitoring circuit</td><td>1P+N / 3P+N</td></tr><tr><td>104</td><td>Frequency in monitoring circuit</td><td>50Hz</td></tr><tr><td>105</td><td>Rated impulse withstand voltage in monitoring circuit</td><td>6kV</td></tr><tr><td>106</td><td>Over-voltage category in monitoring circuit</td><td>III</td></tr><tr><td>201</td><td>Rated operating voltage in control circuit, <span class="math">V_{cc}</span></td><td>5VDC ± 3%</td></tr><tr><td>202</td><td>Power consumption</td><td>&#x3C; 500mW</td></tr><tr><td>203</td><td>Pin 1 – N.C.</td><td>Not connected</td></tr><tr><td>204</td><td>Pin 2 – Test signal</td><td>Digital input</td></tr><tr><td>205</td><td>Pin 3 – DC fault signal</td><td>Digital output</td></tr><tr><td>206</td><td>Pin 4 – AC &#x26; DC fault signal</td><td>Digital output</td></tr><tr><td>207</td><td>Pin 5 – GND</td><td>GND</td></tr><tr><td>208</td><td>Pin 6 – Vcc for 5V</td><td>+5VDC</td></tr><tr><td>301</td><td>Rated DC residual operating current <span class="math">I_{\Delta dc}</span></td><td>6mA</td></tr><tr><td>302</td><td>Rated DC residual non-operating current <span class="math">I_{\Delta ndc}</span></td><td>3mA</td></tr><tr><td>303</td><td>Rated AC residual operating current <span class="math">I_{\Delta n}</span></td><td>30mA</td></tr><tr><td>304</td><td>Rated AC residual non-operating current <span class="math">I_{\Delta nc}</span></td><td>15mA</td></tr><tr><td>305</td><td>Electrical endurance</td><td>20,000</td></tr><tr><td>306</td><td>Rated operating temperature</td><td>-40~85 ℃</td></tr><tr><td>307</td><td>Pollution degree</td><td>2</td></tr></tbody></table>

***

### 3. Residual Current Detection Characteristics

#### Operating Current

<table><thead><tr><th width="81">#</th><th width="311">Operating Current</th><th>PIN 3 (DC)</th><th>PIN 4 (AC &#x26; DC)</th></tr></thead><tbody><tr><td>401</td><td>Smooth DC</td><td>4.0~6.0 mA</td><td>4.0~6.0 mA</td></tr><tr><td>402</td><td>DC rectified from 2 phases</td><td>4.0~7.0 mA</td><td>4.0~7.0 mA</td></tr><tr><td>403</td><td>DC rectified from 3 phases</td><td>4.0~6.2 mA</td><td>4.0~6.2 mA</td></tr><tr><td>404</td><td>Sinewave AC</td><td>-</td><td>22.0~28.0 mA</td></tr><tr><td>405</td><td>A0 pulsating DC</td><td>-</td><td>10.5~42.0 mA</td></tr><tr><td>406</td><td>A90 pulsating DC</td><td>-</td><td>7.5~42.0 mA</td></tr><tr><td>407</td><td>A135 pulsating DC</td><td>-</td><td>3.3~42.0 mA</td></tr></tbody></table>

#### Operating Time

<table><thead><tr><th width="82">#</th><th width="314">Response time</th><th>PIN 3 (DC)</th><th>PIN 4 (AC &#x26; DC)</th></tr></thead><tbody><tr><td>501</td><td>Smooth DC 6mA</td><td>≤ 500 ms</td><td>≤ 500 ms</td></tr><tr><td>502</td><td>Smooth DC 60mA</td><td>≤ 200 ms</td><td>≤ 200 ms</td></tr><tr><td>503</td><td>Smooth DC 200mA</td><td>≤ 70 ms</td><td>≤ 70 ms</td></tr><tr><td>504</td><td>Smooth DC 300mA</td><td>-</td><td>≤ 20 ms</td></tr><tr><td>505</td><td>DC rectified from 2 phases 60mA</td><td>≤ 200 ms</td><td>≤ 200 ms</td></tr><tr><td>506</td><td>DC rectified from 2 phases 200mA</td><td>≤ 70 ms</td><td>≤ 70 ms</td></tr><tr><td>507</td><td>DC rectified from 2 phases 300mA</td><td>-</td><td>≤ 20 ms</td></tr><tr><td>508</td><td>DC rectified from 3 phases 60mA</td><td>≤ 200 ms</td><td>≤ 200 ms</td></tr><tr><td>509</td><td>DC rectified from 3 phases 200mA</td><td>≤ 70 ms</td><td>≤ 70 ms</td></tr><tr><td>510</td><td>DC rectified from 3 phases 300mA</td><td>-</td><td>≤ 20 ms</td></tr><tr><td>511</td><td>AC 30mA</td><td>> 10000 ms</td><td>≤ 80 ms</td></tr><tr><td>512</td><td>AC 60mA</td><td>> 300 ms</td><td>≤ 60 ms</td></tr><tr><td>513</td><td>AC 150mA</td><td>> 80 ms</td><td>≤ 20 ms</td></tr><tr><td>514</td><td>AC 5A</td><td>> 80 ms</td><td>≤ 20 ms</td></tr></tbody></table>

***

### 4. Application Notes

#### Typical integration diagram&#x20;

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FutZxiQGQlb5TPcRHszFG%2Fimage.png?alt=media&amp;token=a96b9e9d-1b50-48bf-a4c0-a7245dcd64f2" alt=""><figcaption></figcaption></figure>

Additional information

* **Ferrite beads** - such as `BLM21PG331SN1D` - are suggested to replace the L1 at some existing charging controller models. C3 might be added in case of limit 5V DC power supply. Please ensure the DC power supply to the 5V version sensor is within the range of 5VDC ± 3%, so as to ensure the proper function of the sensor.
* **NPN transistors** are used internally at the Pin 3 (DC fault signal) and Pin 4 (AC & DC fault signal) of the 5V version sensor, and the direct connection of Pin 3/4 to switching devices such as relays or contactors - is NOT allowed. $$V\_{ce}$$ and $$I\_c$$ of the NPN transistor inside the 5V version sensor are maximally 40V and 50mA.

#### Self-test time chart

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fkm8oeu5qqgA2P6ImycgH%2Fimage.png?alt=media&amp;token=0c9f99fd-dfb0-446c-8be7-2b8c4801f440" alt=""><figcaption></figcaption></figure>

* A self-test excluding offset calibration is activated if Pin 2 - Test is connected to GND for a period of 40ms to 130ms.
* A self-test including offset calibration is activated if Pin 2 - Test is connected to GND for a period of 150ms to 1000ms. *(Note:* $$t\_1$$ *is the response time for internally generated test current.)*

#### Offset calibration time chart

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FCEL6ljHv5a7EFgIWG6ID%2Fimage.png?alt=media&amp;token=a8a6c792-abaf-4b71-a07c-d60602de07b9" alt=""><figcaption></figcaption></figure>

An offset calibration is activated if Pin 2 - Test is connected to GND for a period of **2s to 3s**. An offset calibration can be activated at regular intervals (such as start-up) or after the occur of certain critical events (such as short circuit).

> ⚠️ **Attention**: During the offset calibration, **NO leakage current or any other current may flow through the device** and the relays/contactors must be open. Also, the power supply voltage at Pin 6 Vcc must be stay at **5VDC ± 3%**.

#### Possible Output States

<table><thead><tr><th width="310">Status</th><th>PIN 3 Output (DC Trip)</th><th>PIN 4 Output (AC &#x26; DC Trip)</th></tr></thead><tbody><tr><td>Normal condition</td><td>GND</td><td>GND</td></tr><tr><td><span class="math">I_{\Delta} \ge 6</span> mA DC</td><td>High impedance</td><td>High impedance</td></tr><tr><td><span class="math">I_{\Delta} \ge 30</span> mA AC</td><td>GND <em>1)</em></td><td>High impedance</td></tr><tr><td><span class="math">I_{\Delta} \ge 30</span> mA AC &#x26; <span class="math">I_{\Delta} \ge 6</span> mA DC</td><td>High impedance</td><td>High impedance</td></tr></tbody></table>

> *1) A change from GND to High impedance is allowed, as long as such a change is compliant with IEC 62955.*

***

### 5. Mechanical outline

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FA5g6AYFkiPkljv5E4yHl%2Fimage.png?alt=media&amp;token=80dae139-70c6-4139-9d9c-5c760ba34653" alt=""><figcaption></figcaption></figure>

**Pin Definition: 1**: NC | **2**: Test | **3**: DC fault | **4**: AC\&DC fault | **5**: GND | **6**: 5V DC

***

### 6. Ordering information

<table><thead><tr><th width="65">#</th><th width="197">Order Number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td><strong>BRCS03C-05-L1</strong></td><td><strong>BRCS03C Residual Current Sensor</strong><br>• 5V DC Interface, PCB-mounting (Copper jumper)<br>• Type A 30 mA+DC6mA / DC6mA, 32A, 1P+N / 3P+N<br>• 6 Pin, Pitch=1.9mm</td></tr></tbody></table>

***

### 7. Additional Notes

> 🛑 **ESD Warning**: The sensor is susceptible to be damaged from an ESD event and the personnel should be grounded when handling it.

* Do **NOT** allow strong static electricity near the sensor, because static electricity can cause damage to the ICs inside the sensor. Take static electricity precautions when handling.
* Do **NOT** exceed 260°C for 10 seconds when soldering the sensors of PCB-mounting versions. This is the maximum heat resistance grade of these sensors.
* Do **NOT** solder the sensors with the central isolation cross installed. The central isolation cross can be installed after soldering the sensors.
* Do **NOT** drop the sensor or apply any other mechanical stress to the sensor, as such stresses may change performance characteristics.
* Please place the sensor with an appropriate distance from components that can generate high magnetic fields, such as relays or contactors, to ensure accurate residual current detection.


# BRCS03X - IEC

## BRCS03X - IEC

{% hint style="info" %}
**Applies to:** BRCS03X AC/DC Residual Current Sensor (IEC version, Type A 30mA and DC 6mA (IEC 60947-2-(M)+IEC 62955) / DC 6mA (IEC 62955)) | **Last Updated:** 2026-09-28
{% endhint %}

### 1. Introduction

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fpi9Y0F7rb5w2EHeGxQuk%2Fimage.png?alt=media&amp;token=4710e812-6a51-43f0-bb61-cbbd42bbd673" alt=""><figcaption></figcaption></figure></div>

The BRCS03X is an AC/DC residual current sensor with two separate fault signal outputs – one Pin with DC fault signal output and the other Pin with AC & DC fault signal output. It can be used for built-in RDC-MD (Residual Direct Current Monitoring Device, DC 6mA, IEC 62955) or RDC-PD (Type A 30mA and DC 6mA, Residual Direct Current Protection Device, IEC61008-1 + IEC 62955) at Mode-3 AC chargers. Additionally, it can be used in IC-CPD (In-Cable Control- and Protection Device).

* Accurate measurement and optimization against nuisance tripping
* Cost-effective solution of residual current detection for Mode-2/3 EVSE
* Fast response time facilitating a broad selection of switching devices
* Two fault signal pins for solely DC 6mA and Type-A 30mA+DC 6mA alarming

***

### 2. Technical Data

<table><thead><tr><th width="75">#</th><th width="415">Technical Specification</th><th>Value</th></tr></thead><tbody><tr><td>101</td><td>Rated operating voltage in monitoring circuit</td><td>230/400VAC</td></tr><tr><td>102</td><td>Rated current in monitoring circuit</td><td>≤ 32A</td></tr><tr><td>103</td><td>Poles in monitoring circuit</td><td>1P+N / 3P+N</td></tr><tr><td>104</td><td>Frequency in monitoring circuit</td><td>50Hz</td></tr><tr><td>105</td><td>Rated impulse withstand voltage in monitoring circuit</td><td>6kV</td></tr><tr><td>106</td><td>Over-voltage category in monitoring circuit</td><td>III</td></tr><tr><td>201</td><td>Rated operating voltage in control circuit, <span class="math">V_{cc}</span></td><td>5VDC ± 3%</td></tr><tr><td>202</td><td>Power consumption</td><td>&#x3C; 500mW</td></tr><tr><td>203</td><td>Pin 1 – N.C.</td><td>Not connected</td></tr><tr><td>204</td><td>Pin 2 – Test signal</td><td>Digital input</td></tr><tr><td>205</td><td>Pin 3 – DC fault signal</td><td>Digital output</td></tr><tr><td>206</td><td>Pin 4 – AC &#x26; DC fault signal</td><td>Digital output</td></tr><tr><td>207</td><td>Pin 5 – GND</td><td>GND</td></tr><tr><td>208</td><td>Pin 6 – Vcc for 5V</td><td>+5VDC</td></tr><tr><td>301</td><td>Rated DC residual operating current <span class="math">I_{\Delta dc}</span></td><td>6mA</td></tr><tr><td>302</td><td>Rated DC residual non-operating current <span class="math">I_{\Delta ndc}</span></td><td>3mA</td></tr><tr><td>303</td><td>Rated AC residual operating current <span class="math">I_{\Delta n}</span></td><td>30mA</td></tr><tr><td>304</td><td>Rated AC residual non-operating current <span class="math">I_{\Delta nc}</span></td><td>15mA</td></tr><tr><td>305</td><td>Electrical endurance</td><td>20,000</td></tr><tr><td>306</td><td>Rated operating temperature</td><td>-40~85 ℃</td></tr><tr><td>307</td><td>Pollution degree</td><td>2</td></tr></tbody></table>

***

### 3. Residual Current Detection Characteristics

#### **Operating Current**

<table><thead><tr><th width="72">#</th><th width="321">Operating Current</th><th>PIN 3 (DC)</th><th>PIN 4 (AC &#x26; DC)</th></tr></thead><tbody><tr><td>401</td><td>Smooth DC</td><td>4.0~6.0 mA</td><td>4.0~6.0 mA</td></tr><tr><td>402</td><td>DC rectified from 2 phases</td><td>4.0~7.0 mA</td><td>4.0~7.0 mA</td></tr><tr><td>403</td><td>DC rectified from 3 phases</td><td>4.0~6.2 mA</td><td>4.0~6.2 mA</td></tr><tr><td>404</td><td>Sinewave AC</td><td>-</td><td>22.0~28.0 mA</td></tr><tr><td>405</td><td>A0 pulsating DC</td><td>-</td><td>10.5~42.0 mA</td></tr><tr><td>406</td><td>A90 pulsating DC</td><td>-</td><td>7.5~42.0 mA</td></tr><tr><td>407</td><td>A135 pulsating DC</td><td>-</td><td>3.3~42.0 mA</td></tr></tbody></table>

#### **Operating Time**

<table><thead><tr><th width="77">#</th><th width="321">Response time</th><th>PIN 3 (DC)</th><th>PIN 4 (AC &#x26; DC)</th></tr></thead><tbody><tr><td>501</td><td>Smooth DC 6mA</td><td>≤ 500 ms</td><td>≤ 500 ms</td></tr><tr><td>502</td><td>Smooth DC 60mA</td><td>≤ 200 ms</td><td>≤ 200 ms</td></tr><tr><td>503</td><td>Smooth DC 200mA</td><td>≤ 70 ms</td><td>≤ 70 ms</td></tr><tr><td>504</td><td>Smooth DC 300mA</td><td>-</td><td>≤ 20 ms</td></tr><tr><td>505</td><td>DC rectified from 2 phases 60mA</td><td>≤ 200 ms</td><td>≤ 200 ms</td></tr><tr><td>506</td><td>DC rectified from 2 phases 200mA</td><td>≤ 70 ms</td><td>≤ 70 ms</td></tr><tr><td>507</td><td>DC rectified from 2 phases 300mA</td><td>-</td><td>≤ 20 ms</td></tr><tr><td>508</td><td>DC rectified from 3 phases 60mA</td><td>≤ 200 ms</td><td>≤ 200 ms</td></tr><tr><td>509</td><td>DC rectified from 3 phases 200mA</td><td>≤ 70 ms</td><td>≤ 70 ms</td></tr><tr><td>510</td><td>DC rectified from 3 phases 300mA</td><td>-</td><td>≤ 20 ms</td></tr><tr><td>511</td><td>AC 30mA</td><td>> 10000 ms</td><td>≤ 80 ms</td></tr><tr><td>512</td><td>AC 60mA</td><td>> 300 ms</td><td>≤ 60 ms</td></tr><tr><td>513</td><td>AC 150mA</td><td>> 80 ms</td><td>≤ 20 ms</td></tr><tr><td>514</td><td>AC 5A</td><td>> 80 ms</td><td>≤ 20 ms</td></tr></tbody></table>

***

### 4. Application Notes

#### **Typical integration diagram**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FPI3tUPEUydl9bzPjnj6C%2Fimage.png?alt=media&amp;token=205501bb-c42e-4f66-976e-e52f3c612576" alt=""><figcaption></figcaption></figure>

Additional information

* Ferrite beads - such as `BLM21PG331SN1D` - are suggested to replace the L1 at some existing charging controller models. C3 might be added in case of limit 5V DC power supply. Please ensure the DC power supply to the 5V version sensor is within the range of 5VDC ± 3%, so as to ensure the proper function of the sensor.
* NPN transistors are used internally at the Pin 3 (DC fault signal) and Pin 4 (AC & DC fault signal) of the 5V version sensor, and the direct connection of Pin 3/4 to switching devices such as relays or contactors - is NOT allowed. $$V\_{ce}$$ and $$I\_c$$ of the NPN transistor inside the 5V version sensor are maximally 40V and 50mA.

#### **Self-test time chart**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FIUFljISE1nezHOkAwO1Z%2Fimage.png?alt=media&amp;token=99196db6-f14b-4944-b0af-210c61c92bde" alt=""><figcaption></figcaption></figure>

* A self-test excluding offset calibration is activated if Pin 2 - Test is connected to GND for a period of 40ms to 130ms.
* A self-test including offset calibration is activated if Pin 2 - Test is connected to GND for a period of 150ms to 1000ms. *(Note:* $$t\_1$$ *is the response time for internally generated test current.)*

#### **Offset calibration time chart**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2F46w6aPp1Nc00is0kZPlp%2Fimage.png?alt=media&amp;token=dbb06785-b4db-437b-9df2-c5926e286e8d" alt=""><figcaption></figcaption></figure>

An offset calibration is activated if Pin 2 - Test is connected to GND for a period of **2s to 3s**. An offset calibration can be activated at regular intervals (such as start-up) or after the occur of certain critical events (such as short circuit).

> ⚠️ **Attention**: During the offset calibration, **NO leakage current or any other current may flow through the device** and the relays/contactors must be open. Also, the power supply voltage at Pin 6 Vcc must be stay at **5VDC ± 3%**.

#### **Possible Output States**

<table><thead><tr><th width="317">Status</th><th>PIN 3 Output (DC Trip)</th><th>PIN 4 Output (AC &#x26; DC Trip)</th></tr></thead><tbody><tr><td><strong>Normal condition</strong></td><td>GND</td><td>GND</td></tr><tr><td><span class="math">I_{\Delta} \ge 6</span> mA DC</td><td>High impedance</td><td>High impedance</td></tr><tr><td><span class="math">I_{\Delta} \ge 30</span> mA AC</td><td>GND <em>1)</em></td><td>High impedance</td></tr><tr><td><span class="math">I_{\Delta} \ge 30</span> mA AC &#x26; <span class="math">I_{\Delta} \ge 6</span> mA DC</td><td>High impedance</td><td>High impedance</td></tr></tbody></table>

> *1) A change from GND to High impedance is allowed, as long as such a change is compliant with IEC 62955.*

***

### 5. Mechanical outline

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FdNEg7OhQZ3BlnjM0AjOW%2Fimage.png?alt=media&amp;token=31ef4b5c-529d-4368-b350-4d40363f19fb" alt=""><figcaption></figcaption></figure>

**Pin Definition: 1**: NC | **2**: Test | **3**: DC fault | **4**: AC\&DC fault | **5**: GND | **6**: 5V DC

***

### 6. Ordering information

<table><thead><tr><th width="65">#</th><th width="197">Order Number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td><strong>BRCS03X-05-L2</strong></td><td><strong>BRCS03X Residual Current Sensor</strong><br>• 5V DC Interface, PCB-mounting (Through hole)<br>• Type A 30 mA+DC6mA / DC6mA, 32A, 1P+N / 3P+N<br>• 6 Pin, Pitch=1.9mm</td></tr></tbody></table>

***

### 7. Additional Notes

> 🛑 **ESD Warning**: The sensor is susceptible to be damaged from an ESD event and the personnel should be grounded when handling it.

* Do **NOT** allow strong static electricity near the sensor, because static electricity can cause damage to the ICs inside the sensor. Take static electricity precautions when handling.
* Do **NOT** exceed 260°C for 10 seconds when soldering the sensors. This is the maximum heat resistance grade of these sensors.
* Do **NOT** drop the sensor or apply any other mechanical stress to the sensor, as such stresses may change performance characteristics.
* Please place the sensor with an appropriate distance from components that can generate high magnetic fields, such as relays or contactors, to ensure accurate residual current detection.


# BRCS01V - IEC

## BRCS01V - IEC

{% hint style="info" %}
**Applies to:** BRCS01V AC/DC Residual Current Sensor (IEC version, Type A 30mA and DC 6mA (IEC 62752; IEC 62955) / DC 6mA (IEC 62955)) | **Last Updated:** 2026-09-25
{% endhint %}

### 1. Introduction

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FwNIjQClJYXfzrWcNVWLb%2Fimage.png?alt=media&amp;token=82d85fa3-bbd1-4ee7-9449-2405e9770f5a" alt=""><figcaption></figcaption></figure></div>

The BRCS01V is a high-sensitivity AC/DC residual current sensor, which enables the development of an IEC 62955-compliant Residual Direct Current Detecting Device (RDC-DD) when combined with an EV charging controller and switching devices within EV chargers.

* Cost-effective PCB-mount solution of built-in residual current device for AC EV charger
* Trip Pin output based on solely DC 6mA and Type-A 30mA +DC 6mA detection
* Fast response time facilitating a broad selection of switching devices
* Compact design with 18mm through-hole for charging cable up to 3P+N 32A

***

### 2. Technical Data

<table><thead><tr><th width="75">#</th><th width="415">Technical Specification</th><th>Value</th></tr></thead><tbody><tr><td>101</td><td>Rated operating voltage in monitoring circuit</td><td>230/400VAC</td></tr><tr><td>102</td><td>Rated current in monitoring circuit</td><td>≤ 32A</td></tr><tr><td>103</td><td>Poles in monitoring circuit</td><td>1P+N / 3P+N</td></tr><tr><td>104</td><td>Frequency in monitoring circuit</td><td>50Hz</td></tr><tr><td>105</td><td>Rated impulse withstand voltage in monitoring circuit</td><td>6kV</td></tr><tr><td>106</td><td>Over-voltage category in monitoring circuit</td><td>III</td></tr><tr><td>201</td><td>Rated operating voltage in control circuit, V_{cc}</td><td>5VDC ± 3%</td></tr><tr><td>202</td><td>Power consumption</td><td>&#x3C; 500mW</td></tr><tr><td>203</td><td>Pin 1 – Vcc for 5V</td><td>+5VDC</td></tr><tr><td>204</td><td>Pin 2 – AC&#x26;DC Trip</td><td>Digital output (IC-CPD/RDC-PD)</td></tr><tr><td>205</td><td>Pin 3 – GND</td><td>GND</td></tr><tr><td>206</td><td>Pin 4 – DC Trip</td><td>Digital output (RDC-MD)</td></tr><tr><td>207</td><td>Pin 5 – Test signal</td><td>Digital input</td></tr><tr><td>301</td><td>Rated DC residual operating current <span class="math">I_{\Delta dc}</span></td><td>6mA</td></tr><tr><td>302</td><td>Rated DC residual non-operating current <span class="math">I_{\Delta ndc}</span></td><td>3mA</td></tr><tr><td>303</td><td>Rated AC residual operating current <span class="math">I_{\Delta n}</span></td><td>30mA</td></tr><tr><td>304</td><td>Rated AC residual non-operating current <span class="math">I_{\Delta nc}</span></td><td>15mA</td></tr><tr><td>305</td><td>Electrical endurance</td><td>20,000</td></tr><tr><td>306</td><td>Rated operating temperature</td><td>-40~85 ℃</td></tr><tr><td>307</td><td>Pollution degree</td><td>2</td></tr></tbody></table>

<sup>1)</sup> #303 and #304 apply to only the AC\&DC Trip Pin that sends fault output of Type-A 30mA detection.

***

### 3. Residual Current Detection Characteristics

#### **Operating Current**

<table><thead><tr><th width="81">#</th><th width="314">Operating Current</th><th>AC&#x26;DC trip signal</th><th>DC trip signal</th></tr></thead><tbody><tr><td>401</td><td>Smooth DC</td><td>4.0~6.0 mA</td><td>4.0~6.0 mA</td></tr><tr><td>402</td><td>DC rectified from 2 phases</td><td>4.0~7.0 mA</td><td>4.0~7.0 mA</td></tr><tr><td>403</td><td>DC rectified from 3 phases</td><td>4.0~6.2 mA</td><td>4.0~6.2 mA</td></tr><tr><td>404</td><td>Sinewave AC</td><td>22.0~28.0 mA</td><td>-</td></tr><tr><td>405</td><td>A0 pulsating DC</td><td>10.5~42.0 mA</td><td>-</td></tr><tr><td>406</td><td>A90 pulsating DC</td><td>7.5~42.0 mA</td><td>-</td></tr><tr><td>407</td><td>A135 pulsating DC</td><td>3.3~42.0 mA</td><td>-</td></tr></tbody></table>

#### **Operating Time**

<table><thead><tr><th width="82">#</th><th width="302">Response time</th><th>AC&#x26;DC trip signal</th><th>DC trip signal</th></tr></thead><tbody><tr><td>501</td><td>Smooth DC 6mA</td><td>≤ 500 ms</td><td>≤ 500 ms</td></tr><tr><td>502</td><td>Smooth DC 60mA</td><td>≤ 200 ms</td><td>≤ 200 ms</td></tr><tr><td>503</td><td>Smooth DC 200mA</td><td>≤ 70 ms</td><td>≤ 70 ms</td></tr><tr><td>504</td><td>Smooth DC 300mA</td><td>≤ 20 ms</td><td>-</td></tr><tr><td>505</td><td>DC rectified from 2 phases 60mA</td><td>≤ 200 ms</td><td>≤ 200 ms</td></tr><tr><td>506</td><td>DC rectified from 2 phases 200mA</td><td>≤ 70 ms</td><td>≤ 70 ms</td></tr><tr><td>507</td><td>DC rectified from 2 phases 300mA</td><td>≤ 20 ms</td><td>-</td></tr><tr><td>508</td><td>DC rectified from 3 phases 60mA</td><td>≤ 200 ms</td><td>≤ 200 ms</td></tr><tr><td>509</td><td>DC rectified from 3 phases 200mA</td><td>≤ 70 ms</td><td>≤ 70 ms</td></tr><tr><td>510</td><td>DC rectified from 3 phases 300mA</td><td>≤ 20 ms</td><td>-</td></tr><tr><td>511</td><td>AC 30mA</td><td>≤ 80 ms</td><td>> 10000 ms</td></tr><tr><td>512</td><td>AC 60mA</td><td>≤ 60 ms</td><td>> 300 ms</td></tr><tr><td>513</td><td>AC 150mA</td><td>≤ 20 ms</td><td>> 80 ms</td></tr><tr><td>514</td><td>AC 5A</td><td>≤ 20 ms</td><td>> 80 ms</td></tr></tbody></table>

***

### 4. Application Notes&#x20;

#### **Typical application diagram**

<p align="center"><strong>BRCS01V version                                                                          EV charging controller</strong></p>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FFlXncS9Yhm3sTI10F6iP%2Fimage.png?alt=media&amp;token=4c2dda4a-cfe4-46c3-9ee4-2acec972b73e" alt=""><figcaption></figcaption></figure>

* **Vcc Pin (Power supply pin):** The power supply voltage range to the sensor is 4.85 - 5.15 VDC, and the power ripple is not higher than 150mV. Ferrite beads and filter capacitors are suggested to be placed close to the Vcc pin. In addition, a LDO - such as LP2985A-50DBV- is strongly recommended to be used at the charging controller side.
* **Trip Pins (Fault signal output pin):** When residual current in the circuit exceeds the threshold, the output level changes from low to high. Suggest adding ferrite beads and filter capacitors close to this pin. A direct connection of Pin 2/4 to switching devices- such as relays or contactors- is NOT allowed. The trip signal of Pin 2/4 is suggested to be monitored by the charging controller MCU.
* **TEST Pin (Self-test input pin):** Before starting every charging, this pin is used to perform a simulated test to verify whether the sensor functions correctly.

#### &#x20;Self-test Time Chart

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FyiLvh6JnGOdA05VyBYaY%2Fimage.png?alt=media&amp;token=39c27a6a-54fa-4433-b863-9063e09fc5a9" alt=""><figcaption></figcaption></figure>

A self-test excluding offset calibration is activated if Pin 5 - Test is connected to GND for a period of 40ms to 130ms; A self-test including offset calibration is activated if Pin 5 - Test is connected to GND for a period of 150ms to 1000ms. t1 is the response time for internally generated test current.

#### &#x20;Offset Calibration Time Chart

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FUYt2OuQsWJ2NUkuerV8b%2Fimage.png?alt=media&amp;token=c3139498-6495-4edd-826c-81ba27962f40" alt=""><figcaption></figcaption></figure>

An explicit offset calibration excluding self-test cycle is activated if Pin 5 - Test is connected to GND for a period of 2s to 3s. An offset calibration can be activated at regular intervals (such as start-up) or after the occur of certain critical events (such as short circuit).

{% hint style="warning" %}
**Attention:** During the offset calibration, NO leakage current or any other current may flow through the device and the relays/contactors must be open. Also, the power supply voltage at Pin 1 Vcc must be stay at 5VDC ± 3%.
{% endhint %}

#### **Switching recovery level**

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FJBIEESTltfx8i82NSSHu%2Fimage.png?alt=media&amp;token=03410032-da37-4157-8563-8b5d2fa8a86e" alt=""><figcaption></figcaption></figure></div>

If the trip-level $$I\_{\Delta T}$$ is accomplished the output will change their state from low-level to high level. Depending on the existence of the residual current $$I\_{\Delta}$$, the output will remain in this state until  $$I\_{\Delta}$$ falls below the threshold  $$I\_{\Delta R}$$

* **AC\&DC Trip Pin:** Typical values of $$I\_{\Delta T}$$ DC 5mA & AC 24mA; Typical value of  $$I\_{\Delta R}$$ is 75%.
* **DC Trip Pin:** Typical values of  $$I\_{\Delta T}$$ DC 5mA; Typical value of  $$I\_{\Delta R}$$ is 75%.

***

### 5. Mechanical Outline

**BRCS01V-05-\*:**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FBTj03GguG4s9FvHxPwZe%2Fimage.png?alt=media&amp;token=ce392463-9d98-4f5a-a4d4-c957f57bebf0" alt=""><figcaption></figcaption></figure>

| Pin 1 | Pin 2        | Pin 3 | Pin 4   | Pin 5 |
| ----- | ------------ | ----- | ------- | ----- |
| 5V DC | AC & DC Trip | GND   | DC Trip | Test  |

***

### 6. Ordering Information

<table><thead><tr><th width="75">#</th><th width="200">Order Number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>BRCS01V-05-S1</td><td>BRCS01V Residual Current Sensor, 5V DC<br>Type A 30 mA+DC6mA / DC6mA, 32A, 1P+N / 3P+N</td></tr></tbody></table>

***

### 7. Additional Notes

* Do NOT allow strong static electricity near the sensor, because static electricity can cause damage to the ICs inside the sensor. Take static electricity precautions when handling.
* Do NOT exceed 260°C for 10 seconds when soldering the sensors. This is the maximum heat resistance grade of these sensors.
* Do NOT drop the sensor or apply any other mechanical stress to the sensor, as such stresses may change performance characteristics.
* Please place the sensor with an appropriate distance from components that can generate high magnetic fields, such as relays or contactors, to ensure accurate residual current detection.
* Please refer to the product standards of RCD/RDC-DD (Residual Current Device / Residual Direct Current Detection Device), when designing built-in RCD/RDC-DD for mode-2/3 Electric Vehicle Supply Equipment with the sensor.

{% hint style="danger" %}
The sensor is susceptible to be damaged from an ESD event and the personnel should be grounded when handling it.
{% endhint %}


# BRCS01 - IEC

## BRCS01/01X - IEC

{% hint style="info" %}
**Applies to:** BRCS01/01X AC/DC Residual Current Sensor (IEC 62955) | **Last Updated:** 2026-09-28
{% endhint %}

### 1. Introduction

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FC97zXgqNZ6nUwXZa9zo1%2Fimage.png?alt=media&amp;token=f663ad3f-785d-43dc-b68e-31e4215340d7" alt="" width="375"><figcaption></figcaption></figure></div>

The BRCS01/01X is a residual current sensor for charging equipment of electric vehicles. It supports residual current detection of either solely DC 6mA (IEC 62955) or combined Type-A 30mA and DC 6mA (IEC 62752).

* Simplified 4 pin interface of Vcc, GND, Test and Trip
* Residual current detection either solely DC 6mA or combined Type A 30mA and DC 6mA
* Fast residual current detection facilitates broad selection of switching relays and contactors
* Cost-effective solution of residual current detection for charging system of Electric Vehicles
* Available in both **Flexible** and **PCB-mount** variants

***

### 2. Technical Data

<table><thead><tr><th width="72">#</th><th width="378">Technical Specification</th><th width="158">BRCS01-ADC-* / BRCS01X-ADC-*</th><th>BRCS01-DC6-* / BRCS01X-DC6-*</th></tr></thead><tbody><tr><td>101</td><td>Rated operating voltage in monitoring circuit</td><td>230/400VAC</td><td>230/400VAC</td></tr><tr><td>102</td><td>Rated current in monitoring circuit</td><td>≤ 32A</td><td>≤ 32A</td></tr><tr><td>103</td><td>Poles in monitoring circuit</td><td>1P+N / 3P+N</td><td>1P+N / 3P+N</td></tr><tr><td>104</td><td>Frequency in monitoring circuit</td><td>50Hz</td><td>50Hz</td></tr><tr><td>105</td><td>Rated impulse withstand voltage in monitoring circuit</td><td>4kV</td><td>4kV</td></tr><tr><td>106</td><td>Over-voltage category in monitoring circuit</td><td>III</td><td>III</td></tr><tr><td>201</td><td>Rated operating voltage in control circuit</td><td>5VDC ± 3%</td><td>5VDC ± 3%</td></tr><tr><td>202</td><td>Power consumption</td><td>&#x3C; 500mW</td><td>&#x3C; 500mW</td></tr><tr><td>203</td><td>Pin 1 - Vcc</td><td>+5VDC</td><td>+5VDC</td></tr><tr><td>204</td><td>Pin 2 - GND</td><td>GND</td><td>GND</td></tr><tr><td>205</td><td>Pin 3 - Test signal input</td><td>Test <sup>1)</sup></td><td>Test <sup>1)</sup></td></tr><tr><td>206</td><td>Pin 4 - Fault signal output</td><td>Trip</td><td>Trip</td></tr><tr><td>301</td><td>Rated DC residual operating current <span class="math">I_{\Delta dc}</span></td><td>6mA</td><td>6mA</td></tr><tr><td>302</td><td>Rated DC residual non-operating current <span class="math">I_{\Delta ndc}</span></td><td>3mA</td><td>3mA</td></tr><tr><td>303</td><td>Rated AC residual operating current <span class="math">I_{\Delta n}</span></td><td>30mA</td><td>-</td></tr><tr><td>304</td><td>Rated AC residual non-operating current <span class="math">I_{\Delta nc}</span></td><td>15mA</td><td>-</td></tr><tr><td>305</td><td>Electrical endurance</td><td>20,000</td><td>20,000</td></tr><tr><td>306</td><td>Rated operating temperature</td><td>-40~85 ℃</td><td>-40~85 ℃</td></tr><tr><td>307</td><td>Pollution degree</td><td>2</td><td>2</td></tr></tbody></table>

***

### 3. Residual Current Detection Characteristics

#### **Operating Current**

<table><thead><tr><th width="79">#</th><th width="348">Description</th><th>AC&#x26;DC fault signal</th><th>DC fault signal</th></tr></thead><tbody><tr><td>401</td><td>Operating current for smooth DC</td><td>4.0~6.0 mA</td><td>4.0~6.0 mA</td></tr><tr><td>402</td><td>Operating current for DC rectified from 2 phases</td><td>4.0~7.0 mA</td><td>4.0~7.0 mA</td></tr><tr><td>403</td><td>Operating current for DC rectified from 3 phases</td><td>4.0~6.2 mA</td><td>4.0~6.2 mA</td></tr><tr><td>404</td><td>Operating current for sinewave AC</td><td>22.0~28.0 mA</td><td>-</td></tr><tr><td>405</td><td>Operating current for A0 pulsating DC</td><td>10.5~42.0 mA</td><td>-</td></tr><tr><td>406</td><td>Operating current for A90 pulsating DC</td><td>7.5~42.0 mA</td><td>-</td></tr><tr><td>407</td><td>Operating current for A135 pulsating DC</td><td>3.3~42.0 mA</td><td>-</td></tr></tbody></table>

#### **Operating Time**

<table><thead><tr><th width="82">#</th><th width="345">Description</th><th>AC&#x26;DC fault signal</th><th>DC fault signal</th></tr></thead><tbody><tr><td>501</td><td>Response time for 6mA smooth DC residual current</td><td>≤ 500 ms</td><td>≤ 500 ms</td></tr><tr><td>502</td><td>Response time for 60mA smooth DC residual current</td><td>≤ 200 ms</td><td>≤ 200 ms</td></tr><tr><td>503</td><td>Response time for 200mA smooth DC residual current</td><td>≤ 70 ms</td><td>≤ 70 ms</td></tr><tr><td>504</td><td>Response time for 300mA smooth DC residual current</td><td>≤ 20 ms</td><td>-</td></tr><tr><td>505</td><td>Response time for 60mA DC rectified from 2 phases</td><td>≤ 200 ms</td><td>≤ 200 ms</td></tr><tr><td>506</td><td>Response time for 200mA DC rectified from 2 phases</td><td>≤ 70 ms</td><td>≤ 70 ms</td></tr><tr><td>507</td><td>Response time for 300mA DC rectified from 2 phases</td><td>≤ 20 ms</td><td>-</td></tr><tr><td>508</td><td>Response time for 60mA DC rectified from 3 phases</td><td>≤ 200 ms</td><td>≤ 200 ms</td></tr><tr><td>509</td><td>Response time for 200mA DC rectified from 3 phases</td><td>≤ 70 ms</td><td>≤ 70 ms</td></tr><tr><td>510</td><td>Response time for 300mA DC rectified from 3 phases</td><td>≤ 20 ms</td><td>-</td></tr><tr><td>511</td><td>Response time for 30mA AC residual current</td><td>≤ 80 ms</td><td>> 10000 ms</td></tr><tr><td>512</td><td>Response time for 60mA AC residual current</td><td>≤ 60 ms</td><td>> 300 ms</td></tr><tr><td>513</td><td>Response time for 150mA AC residual current</td><td>≤ 20 ms</td><td>> 80 ms</td></tr><tr><td>514</td><td>Response time for 5A AC residual current</td><td>≤ 20 ms</td><td>> 80 ms</td></tr></tbody></table>

***

### 4. Application Notes

{% tabs %}
{% tab title="PCB-mount Version" %}
By adjusting the resistors between Fault signal pin of the BRCS01/01X sensors and charging controller MCU, GPIO ports of a 3.3V MCU at an EV charging controller can be used to read Normal/Trip status.

#### **Typical application diagram**

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fdnq14q0yTBiBEv3Q4ang%2Fimage.png?alt=media&amp;token=a441e321-1e01-4fb6-a32a-8b3543e1c36a" alt="" width="533"><figcaption></figcaption></figure></div>

* R0=10K ohm (Built in BRCS01/01X)
* R3=R4=R5=5.1K ohm
* R1=330 ohm, R2=680 ohm
* D1: TVS SMBJ5.0A
* Q1: S9013
* C1=C2=100nF
* <Normal@0.3VDC>, <TRIP@3.3VDC>

> ⚠️ **Attention**: More electronic components at charging controllers than those showed in the simplified diagram might be added depending on the overall charging controller design.

#### **Self-test time chart**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FLziDulN1T8Foj8cA1qiZ%2Fimage.png?alt=media&amp;token=720f0dc3-d408-4529-a9bd-187ec206f33e" alt=""><figcaption></figcaption></figure>

$$t\_1$$ is the response time for internally generated test current. A self-test excluding offset calibration is activated if Pin 3 - Test is connected to ground for a period of **200ms to 4s** (Normally 300ms is recommended).

#### **Offset calibration**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2F9XEEKM7WhHT7Vnk1Vixz%2Fimage.png?alt=media&amp;token=5e0eb267-cae3-4077-95a3-7927963df7fa" alt=""><figcaption></figcaption></figure>

* BRCS01 enters calibration mode when the Test pin is connected to ground for 4–5 seconds (recommended: 4.5 s ± 5%). During calibration, the Trip pin does not output any high-level signal.
* BRCS01X enters calibration mode when the Test pin is connected to ground for 2–3 seconds (recommended: 2.5 s ± 5%). During calibration, the Trip pin outputs a high-level signal for approximately 300 ms, allowing users to clearly identify when the calibration process has begun.

&#x20;An offset calibration can be activated at regular intervals (e.g. startup) or after the occur of certain critical events (e.g. short circuit).

> ⚠️ **Attention**: During the offset calibration, **NO leakage current or any other current may flow through the sensor**. Please ensure voltage supply of **5VDC ± 3%** to the sensor and remain the main-circuit contactors/relays open.
> {% endtab %}

{% tab title="Flexible Version" %}
IEC 62955 Annex N.8.3 specifies that the M-module with facilitate for connection of an external detection module shall cause opening of the switching or protective device within 10s, if the external detection module is disconnected. A three-level voltage output at Fault signal pin of the BRCS01/01X sensors facilitate built-in RDC-DD at EV charger to meet this requirement.

#### **Typical application diagram**

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2F6Q8AyaKUmJb40SeupSEY%2Fimage.png?alt=media&amp;token=3d3bd65e-c9fb-4069-a7d7-827368195f3e" alt="" width="563"><figcaption></figcaption></figure></div>

* R0=10K ohm (Built in BRCS01/01X)
* R3=R4=5.1K ohm
* R1=R2=10K ohm
* D1: TVS SMBJ5.0A
* Q1: S9013
* C1=C2=100nF
* <Normal@2.5V>, <TRIP@5.0V>, OFF\@0V
* Fault output with 3 level voltage (Possible to fulfil IEC 62955 Annex N.8.3)

⚠️ **Attention**: More electronic components at charging controllers than those showed in the simplified diagram might be added depending on the overall charging controller design.

#### **Self-test time chart**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FLziDulN1T8Foj8cA1qiZ%2Fimage.png?alt=media&amp;token=720f0dc3-d408-4529-a9bd-187ec206f33e" alt=""><figcaption></figcaption></figure>

$$t\_1$$ is the response time for internally generated test current. A self-test excluding offset calibration is activated if Pin 3 - Test is connected to ground for a period of **200ms to 4s** (Normally 300ms is recommended).

#### **Offset calibration**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2F9XEEKM7WhHT7Vnk1Vixz%2Fimage.png?alt=media&amp;token=5e0eb267-cae3-4077-95a3-7927963df7fa" alt=""><figcaption></figcaption></figure>

* BRCS01 enters calibration mode when the Test pin is connected to ground for 4–5 seconds (recommended: 4.5 s ± 5%). During calibration, the Trip pin does not output any high-level signal.
* BRCS01X enters calibration mode when the Test pin is connected to ground for 2–3 seconds (recommended: 2.5 s ± 5%). During calibration, the Trip pin outputs a high-level signal for approximately 300 ms, allowing users to clearly identify when the calibration process has begun.

&#x20;An offset calibration can be activated at regular intervals (e.g. startup) or after the occur of certain critical events (e.g. short circuit).

> ⚠️ **Attention**: During the offset calibration, **NO leakage current or any other current may flow through the sensor**. Please ensure voltage supply of **5VDC ± 3%** to the sensor and remain the main-circuit contactors/relays open.
> {% endtab %}
> {% endtabs %}

***

### 5. Additional Product Illustration

{% tabs %}
{% tab title="PCB-mount version" %}

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FuEf2CGrfTTVueZ3bhyr3%2Fimage.png?alt=media&amp;token=cd206782-93c1-44ee-be4d-25641dc30a18" alt=""><figcaption></figcaption></figure></div>

* BRCS01-DC6-L / BRCS01-ADC-L
* BRCS01X-DC6-L / BRCS01X-ADC-L

**4 Pin Interface:**

* **Pin 1:** 5VDC
* **Pin 2:** GND
* **Pin 3:** TEST
* **Pin 4:** TRIP

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2F3OegbRuQeAy6OTrpSnZx%2Fimage.png?alt=media&amp;token=6eada56d-eb98-479a-b619-89727f572959" alt=""><figcaption></figcaption></figure> <figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FFwSnDZUWQ3SI96amNTgj%2Fimage.png?alt=media&amp;token=f2553b83-38b5-4cda-8c8f-ba5994e6627a" alt=""><figcaption></figcaption></figure></div>
{% endtab %}

{% tab title="Flexible version" %}

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2F0kaharXA3XMRIZRM41mv%2Fimage.png?alt=media&amp;token=31a035bc-3693-4a2d-87b5-4483562a7bc7" alt="" width="280"><figcaption></figcaption></figure></div>

**16.2mm Aperture**

* BRCS01-DC6-H2 / BRCS01-ADC-H2
* BRCS01X-DC6-H2 / BRCS01X-ADC-H2

**XHB 2.5mm connector:**

* **Red:** 5VDC
* **Black:** GND
* **Green/Yellow:** TEST
* **White:** TRIP

MOLEX 0353120460 can be used at the charging controller side.
{% endtab %}
{% endtabs %}

***

### 6. Ordering Information

<table><thead><tr><th width="71">#</th><th width="183">Order Number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td><strong>BRCS01X-ADC-H2</strong></td><td>⚠️NRND<br>BRCS01X Residual Current Sensor (Closed-loop fluxgate), A30+DC6mA<br>Flexible, XHB 4Pin, Pitch=2.5mm, 220mm cable</td></tr><tr><td>2</td><td><strong>BRCS01X-DC6-H2</strong></td><td>⚠️NRND<br>BRCS01X Residual Current Sensor (Closed-loop fluxgate), DC6mA<br>Flexible, XHB 4Pin, Pitch=2.5mm, 220mm cable</td></tr><tr><td>3</td><td><strong>BRCS01X-ADC-L</strong></td><td>BRCS01X Residual Current Sensor (Closed-loop fluxgate), A30+DC6mA<br>PCB-mounting, 4Pin, Pitch=2.54mm</td></tr><tr><td>4</td><td><strong>BRCS01X-DC6-L</strong></td><td>BRCS01X Residual Current Sensor (Closed-loop fluxgate), DC6mA<br>PCB-mounting, 4Pin, Pitch=2.54mm</td></tr><tr><td>5</td><td><strong>BRCS01-ADC-H2</strong></td><td><p>⚠️NRND</p><p>BRCS01 Residual Current Sensor (Open-loop fluxgate), A30+DC6mA<br>Flexible, XHB 4Pin, Pitch=2.5mm, 220mm cable</p></td></tr><tr><td>6</td><td><strong>BRCS01-DC6-H2</strong></td><td><p>⚠️NRND</p><p>BRCS01 Residual Current Sensor (Open-loop fluxgate), DC6mA<br>Flexible, XHB 4Pin, Pitch=2.5mm, 220mm cable</p></td></tr><tr><td>7</td><td><strong>BRCS01-ADC-L</strong></td><td>⚠️NRND<br>BRCS01 Residual Current Sensor (Open-loop fluxgate), A30+DC6mA<br>PCB-mounting, 4Pin, Pitch=2.54mm</td></tr><tr><td>8</td><td><strong>BRCS01-DC6-L</strong></td><td>⚠️NRND<br>BRCS01 Residual Current Sensor (Open-loop fluxgate), DC6mA<br>PCB-mounting, 4Pin, Pitch=2.54mm</td></tr></tbody></table>

***

### 8. Additional Notes

> 🛑 **ESD Warning**: The sensor is susceptible to be damaged from an ESD event and the personnel should be grounded when handling it.

* Do **NOT** allow strong static electricity near the sensor, because static electricity can cause damage to the ICs inside the sensor. Take static electricity precautions when handling.
* Do **NOT** exceed 260°C for 10 seconds when soldering the sensors of PCB-mounting versions. This is the maximum heat resistance grade of these sensors.
* Do **NOT** drop the sensor or apply any other mechanical stress to the sensor, as such stresses may change performance characteristics.
* Please place the sensor with an appropriate distance from components that can generate high magnetic fields, such as relays or contactors, to ensure accurate residual current detection.


# BRCS01C - UL

## BRCS01C-U5/U6 - UL & IEC

{% hint style="info" %}
**Applies to:** BRCS01C-U5/U6 Residual Current Sensor (UL 2231-2 (CCID20) and IEC 62955 / IEC 62752) | **Last Updated:** 2026-09-28
{% endhint %}

### 1. Introduction

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FzpVrNfWylgzdex04LMqD%2Fimage.png?alt=media&amp;token=c23da17b-bd1c-4ac2-9bd7-c7d92dd74b5b" alt=""><figcaption></figcaption></figure></div>

The BRCS01C-U5/BRCS01C-U6 is an AC/DC residual current sensor with two separate fault signal outputs – one Pin conforming to UL2231-2 (CCID20) and the other Pin conforming to IEC 62955 or IEC 62752. It can be used for built-in residual current protection system at AC charging stations.

* Digital outputs of fault detection conforming to UL2231-2 (CCID20) and IEC 62955 / IEC 62752
* Cost-effective solution of residual current detection for mode-2/3 EVSE
* Fast response time facilitating a broad selection of switching devices
* Accurate measurement and optimization against nuisance tripping

***

### 2. Technical Data

<table><thead><tr><th width="79">#</th><th width="416">Technical Specification</th><th>BRCS01C-U5</th><th>BRCS01C-U6</th></tr></thead><tbody><tr><td>101</td><td>Rated current in monitoring circuit (1phase/3phase)</td><td>80A / 40A</td><td>80A / 40A</td></tr><tr><td>102</td><td>Rated frequency in monitoring circuit</td><td>60Hz</td><td>60Hz</td></tr><tr><td>103</td><td>Rated impulse withstand voltage in monitoring circuit</td><td>6kV</td><td>6kV</td></tr><tr><td>104</td><td>Over-voltage category in monitoring circuit</td><td>III</td><td>III</td></tr><tr><td>201</td><td>Rated operating voltage in control circuit, <span class="math">V_{cc}</span></td><td>5VDC ± 3%</td><td>5VDC ± 3%</td></tr><tr><td>202</td><td>Power consumption</td><td>&#x3C; 500mW</td><td>&#x3C; 500mW</td></tr><tr><td>203</td><td>Pin 1 – Vcc for 5V</td><td>+5VDC</td><td>+5VDC</td></tr><tr><td>204</td><td>Pin 2 – Fault signal: X20-UL2231 (CCID20)</td><td>Digital output</td><td>Digital output</td></tr><tr><td>205</td><td>Pin 3 – GND</td><td>GND</td><td>GND</td></tr><tr><td>206</td><td>Pin 4 – CAL (Calibration)</td><td>Digital input</td><td>Digital input</td></tr><tr><td>207</td><td>Pin 5 – Test signal</td><td>Digital input</td><td>Digital input</td></tr><tr><td>208</td><td>Pin 6 – Fault signal: X6-IEC62955 (RDC-MD) or X30-IEC62752 (IC-CPD)</td><td>Digital output (RDC-MD)</td><td>Digital output (IC-CPD)</td></tr><tr><td>301</td><td>Rated DC residual operating current <span class="math">I_{\Delta dc}</span> (IEC 62955)</td><td>6mA</td><td>6mA</td></tr><tr><td>302</td><td>Rated DC residual non-operating current <span class="math">I_{\Delta ndc}</span> (IEC 62955)</td><td>3mA</td><td>3mA</td></tr><tr><td>303</td><td>Rated AC residual operating current <span class="math">I_{\Delta n}</span> (UL2231-2)</td><td>20mA</td><td>20mA</td></tr><tr><td>304</td><td>Rated AC residual non-operating current <span class="math">I_{\Delta nc}</span> (UL2231-2)</td><td>15mA</td><td>15mA</td></tr><tr><td>305</td><td>Rated AC residual operating current <span class="math">I_{\Delta n}</span> (IEC 62752)</td><td>-</td><td>30mA</td></tr><tr><td>306</td><td>Rated AC residual non-operating current <span class="math">I_{\Delta nc}</span> (IEC 62752)</td><td>-</td><td>15mA</td></tr><tr><td>307</td><td>Electrical endurance</td><td>20,000</td><td>20,000</td></tr><tr><td>308</td><td>Rated operating temperature</td><td>-40~85 ℃</td><td>-40~85 ℃</td></tr><tr><td>309</td><td>Pollution degree</td><td>2</td><td>2</td></tr></tbody></table>

***

### 3. Residual Current Detection Characteristics

#### **PIN 6 (X6/X30 Output) - IEC 62955 / IEC 62752**

**Operating Current**

<table><thead><tr><th width="91.22216796875">#</th><th width="369.77783203125">Operating Current</th><th>PIN 6 (X6) @BRCS01C-U5</th><th>PIN 6 (X30) @BRCS01C-U6</th></tr></thead><tbody><tr><td>401</td><td>Smooth DC</td><td>4.0~6.0 mA</td><td>4.0~6.0 mA</td></tr><tr><td>402</td><td>DC rectified from 2 phases</td><td>4.0~7.0 mA</td><td>4.0~7.0 mA</td></tr><tr><td>403</td><td>DC rectified from 3 phases</td><td>4.0~6.2 mA</td><td>4.0~6.2 mA</td></tr><tr><td>404</td><td>Sinewave AC</td><td>-</td><td>22.0~28.0 mA</td></tr><tr><td>405</td><td>A0 pulsating DC</td><td>-</td><td>10.5~42.0 mA</td></tr><tr><td>406</td><td>A90 pulsating DC</td><td>-</td><td>7.5~42.0 mA</td></tr><tr><td>407</td><td>A135 pulsating DC</td><td>-</td><td>3.3~42.0 mA</td></tr></tbody></table>

**Operating Time**

<table><thead><tr><th width="103.4444580078125">#</th><th width="355.7777099609375">Response time</th><th>PIN 6 (X6) @BRCS01C-U5</th><th>PIN 6 (X30) @BRCS01C-U6</th></tr></thead><tbody><tr><td>501</td><td>Smooth DC 6mA</td><td>≤ 500 ms</td><td>≤ 500 ms</td></tr><tr><td>502</td><td>Smooth DC 60mA</td><td>≤ 200 ms</td><td>≤ 200 ms</td></tr><tr><td>503</td><td>Smooth DC 200mA</td><td>≤ 70 ms</td><td>≤ 70 ms</td></tr><tr><td>504</td><td>Smooth DC 300mA</td><td>-</td><td>≤ 20 ms</td></tr><tr><td>505</td><td>DC rectified from 2 phases 60mA</td><td>≤ 200 ms</td><td>≤ 200 ms</td></tr><tr><td>506</td><td>DC rectified from 2 phases 200mA</td><td>≤ 70 ms</td><td>≤ 70 ms</td></tr><tr><td>507</td><td>DC rectified from 2 phases 300mA</td><td>-</td><td>≤ 20 ms</td></tr><tr><td>508</td><td>DC rectified from 3 phases 60mA</td><td>≤ 200 ms</td><td>≤ 200 ms</td></tr><tr><td>509</td><td>DC rectified from 3 phases 200mA</td><td>≤ 70 ms</td><td>≤ 70 ms</td></tr><tr><td>510</td><td>DC rectified from 3 phases 300mA</td><td>-</td><td>≤ 20 ms</td></tr><tr><td>511</td><td>AC 30mA</td><td>> 10000 ms</td><td>≤ 80 ms</td></tr><tr><td>512</td><td>AC 60mA</td><td>> 300 ms</td><td>≤ 60 ms</td></tr><tr><td>513</td><td>AC 150mA</td><td>> 80 ms</td><td>≤ 20 ms</td></tr><tr><td>514</td><td>AC 5A</td><td>> 80 ms</td><td>≤ 20 ms</td></tr></tbody></table>

#### **PIN 2 (X20 Output) - UL2231-2 (CCID-20)**

**Operating Current**

<table><thead><tr><th width="107.5555419921875">#</th><th width="356.111083984375">Operating Current</th><th>PIN 2 (X20) @BRCS01C-U5/U6</th></tr></thead><tbody><tr><td>601</td><td>60Hz sinewave AC</td><td>15.0~20.0 mA</td></tr><tr><td>602</td><td>150Hz sinewave AC</td><td>15.0~34.5 mA</td></tr><tr><td>603</td><td>400Hz sinewave AC</td><td>15.0~69.6 mA</td></tr><tr><td>604</td><td>Smooth DC</td><td>20.0~56.0 mA</td></tr></tbody></table>

**Operating Time**

<table><thead><tr><th width="110.8887939453125">#</th><th width="354.111083984375">Response time</th><th>PIN 2 (X20) @BRCS01C-U5/U6</th></tr></thead><tbody><tr><td>701</td><td>20mA AC residual current (60Hz)</td><td>≤ 500 ms</td></tr><tr><td>702</td><td>100mA AC residual current (60Hz)</td><td>≤ 20 ms</td></tr><tr><td>703</td><td>264mA AC residual current (60Hz)</td><td>≤ 15 ms</td></tr><tr><td>704</td><td>56mA smooth DC residual current</td><td>≤ 40 ms</td></tr><tr><td>705</td><td>100mA smooth DC residual current</td><td>≤ 20 ms</td></tr></tbody></table>

***

### 4. Application Notes

**Typical application diagram**

<p align="center"><strong>BRCS01C-U5/U6                                                                                  EV charging controller</strong></p>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2F1UhcVhTFCnqw6fjaZDWn%2Fimage.png?alt=media&amp;token=abffdd56-e22a-487d-8970-fcd5801e34fc" alt=""><figcaption></figcaption></figure>

Additional information

* **Attention:** A direct connection of Pin 2/6 to switching devices such as relays or contactors - is **NOT allowed**. The trip signal of Pin 2/6 is suggested to be monitored by the charging controller MCU.

#### **Self-test time chart**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FfaL2HNlW7SefIHKFyIMP%2Fimage.png?alt=media&amp;token=9a07f98c-b81a-4f69-97d0-671aec849fc3" alt=""><figcaption></figcaption></figure>

A self-test excluding offset calibration is activated if Pin 5 - Test is connected to a high level for a period **above 40ms**. *(Note:* $$t\_1$$ *is the response time for internally generated test current.)*

#### **Offset calibration time chart**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fmbj0U6BJiMjOy4q0MQkH%2Fimage.png?alt=media&amp;token=b37490b0-2718-44ec-b705-6857868eb27a" alt=""><figcaption></figcaption></figure>

An offset calibration is activated if Pin 4 - CAL is connected to GND for a period between **50ms and 100ms**. An offset calibration can be activated at regular intervals (such as start-up) or after the occur of certain critical events (such as short circuit).

> ⚠️ **Attention**: During the offset calibration, **NO leakage current or any other current may flow through the device** and the relays/contactors must be open. Also, the power supply voltage at Pin 1 Vcc must be stay at **5VDC ± 3%**.

#### **Switching recovery level**

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2F18TAja60S3T4HpAbm8yu%2Fimage.png?alt=media&amp;token=71302da5-a062-48ce-8e09-06d3069ee23c" alt=""><figcaption></figcaption></figure></div>

If the trip-level $$I\_{\Delta T}$$ is accomplished the output will change their state from low-level to high level. Depending on the existence of the residual current $$I\_{\Delta}$$, the output will remain in this state until $$I\_{\Delta}$$ falls below the threshold $$I\_{\Delta R}$$.

* **X20 Pin (CCID20):** Typical values of $$I\_{\Delta T}$$ DC 26mA & AC 17.5mA; Typical value of $$I\_{\Delta R}$$ is 75%.
* **X30 Pin (IEC 62752):** Typical values of $$I\_{\Delta T}$$ DC 5mA & AC 24mA; Typical value of $$I\_{\Delta R}$$ is 75%.
* **X6 Pin (IEC 62955):** Typical values of $$I\_{\Delta T}$$ DC 5mA; Typical value of $$I\_{\Delta R}$$ is 75%.

***

### 5. Mechanical outline

BRCS01C-U5 / BRCS01C-U6:

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FVj6qN7YA5TZyt8iqwXz8%2Fimage.png?alt=media&amp;token=e6871dda-07f7-4922-a997-a8b6762a4149" alt=""><figcaption></figcaption></figure>

<table><thead><tr><th width="144.6666259765625">Model</th><th width="92.4444580078125">Pin 1</th><th width="111.3333740234375">Pin 2</th><th width="102.4444580078125">Pin 3</th><th width="95.77783203125">Pin 4</th><th width="85.77783203125">Pin 5</th><th width="118">Pin 6</th></tr></thead><tbody><tr><td><strong>BRCS01C-U5-</strong>*</td><td>5V DC</td><td>AC &#x26; DC fault (UL2231(CCID20))</td><td>GND</td><td>CAL</td><td>Test</td><td>DC fault (IEC 62955)</td></tr><tr><td><strong>BRCS01C-U6-</strong>*</td><td>5V DC</td><td>AC &#x26; DC fault (UL2231(CCID20))</td><td>GND</td><td>CAL</td><td>Test</td><td>AC &#x26; DC fault (IEC 62752)</td></tr></tbody></table>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fvn0IVTuLvSKAtqJWCZAS%2Fimage.png?alt=media&amp;token=0b6e9ff0-c9e8-409a-9b94-1191f646e39a" alt=""><figcaption></figcaption></figure>

***

### 6. Ordering information

<table><thead><tr><th width="86.4444580078125">#</th><th width="218.333251953125">Order Number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td><strong>BRCS01C-U5-H1</strong></td><td>BRCS01C Residual Current Sensor, 5V DC Interface, Flexible<br>UL2231-2(CCID20) &#x26; IEC62955, 1P+N(80A) / 3P+N(40A)</td></tr><tr><td>2</td><td><strong>BRCS01C-U6-H1</strong></td><td>BRCS01C Residual Current Sensor, 5V DC Interface, Flexible<br>UL2231-2(CCID20) &#x26; IEC62752, 1P+N(80A) / 3P+N(40A)</td></tr><tr><td>3</td><td><strong>BCHY6HY6-N030</strong></td><td>300mm cable with 2×6PIN HY2.0 Connectors <sup>1) 2)</sup></td></tr></tbody></table>

> *1) BM6B-PASS (JST, SMT), BM6B-PASK (JST, DIP), A2012WV-S-6P (CJT, SMT) or A2012WV-6P (CJT, DIP) can be used at the charging controller side.*\
> *2) Specific customization requirements can be provided upon request.*

***

### 7. Additional Notes

> 🛑 **ESD Warning**: The sensor is susceptible to be damaged from an ESD event and the personnel should be grounded when handling it.

* Do **NOT** allow strong static electricity near the sensor, because static electricity can cause damage to the ICs inside the sensor. Take static electricity precautions when handling.
* Do **NOT** drop the sensor or apply any other mechanical stress to the sensor, as such stresses may change performance characteristics.
* Please place the sensor with an appropriate distance from components that can generate high magnetic fields, such as relays or contactors, to ensure accurate residual current detection.


# BRCS03C - UL

## BRCS03C-U5/U6 - UL & IEC

{% hint style="info" %}
**Applies to:** BRCS03C-U5/U6 Residual Current Sensor (UL 2231-2 (CCID20) and IEC 62955 / IEC 62752) | **Last Updated:** 2026-09-28
{% endhint %}

### 1. Introduction

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FStOM7m4S40r8nSKvknCF%2Fimage.png?alt=media&amp;token=567e96d4-7db2-4596-9207-5e9f13f15b49" alt=""><figcaption></figcaption></figure></div>

The BRCS03C-U5/BRCS03C-U6 is an AC/DC residual current sensor with two separate fault signal outputs – one Pin conforming to UL2231-2 (CCID20) and the other Pin conforming to IEC 62955 or IEC 62752. It can be used for built-in residual current protection system at AC charging stations.

* Digital outputs of fault detection conforming to UL2231-2 (CCID20) and IEC 62955 / IEC 62752
* Cost-effective solution of residual current detection for mode-2/3 EVSE
* Fast response time facilitating a broad selection of switching devices
* Accurate measurement and optimization against nuisance tripping

***

### 2. Technical Data

<table><thead><tr><th width="106.7777099609375">#</th><th width="372.5555419921875">Technical Specification</th><th>BRCS03C-U5</th><th>BRCS03C-U6</th></tr></thead><tbody><tr><td>101</td><td>Poles in monitoring circuit</td><td>1P+N / 3P+N</td><td>1P+N / 3P+N</td></tr><tr><td>102</td><td>Rated current in monitoring circuit</td><td>32A</td><td>32A</td></tr><tr><td>103</td><td>Rated frequency in monitoring circuit</td><td>60Hz</td><td>60Hz</td></tr><tr><td>104</td><td>Rated impulse withstand voltage in monitoring circuit</td><td>6kV</td><td>6kV</td></tr><tr><td>105</td><td>Over-voltage category in monitoring circuit</td><td>III</td><td>III</td></tr><tr><td>201</td><td>Rated operating voltage in control circuit, <span class="math">V_{cc}</span></td><td>5VDC ± 3%</td><td>5VDC ± 3%</td></tr><tr><td>202</td><td>Power consumption</td><td>&#x3C; 500mW</td><td>&#x3C; 500mW</td></tr><tr><td>203</td><td>Pin 1 – N.C.</td><td>Not connected</td><td>Not connected</td></tr><tr><td>204</td><td>Pin 2 – Test signal</td><td>Digital input</td><td>Digital input</td></tr><tr><td>205</td><td>Pin 3 – Fault signal: X6-IEC62955 (RDC-MD) or X30-IEC62752 (IC-CPD)</td><td>Digital output (RDC-MD)</td><td>Digital output (IC-CPD)</td></tr><tr><td>206</td><td>Pin 4 – Fault signal: X20-UL2231 (CCID20)</td><td>Digital output</td><td>Digital output</td></tr><tr><td>207</td><td>Pin 5 – GND</td><td>GND</td><td>GND</td></tr><tr><td>208</td><td>Pin 6 – Vcc for 5V</td><td>+5VDC</td><td>+5VDC</td></tr><tr><td>301</td><td>Rated DC residual operating current <span class="math">I_{\Delta dc}</span> (IEC 62955)</td><td>6mA</td><td>6mA</td></tr><tr><td>302</td><td>Rated DC residual non-operating current <span class="math">I_{\Delta ndc}</span> (IEC 62955)</td><td>3mA</td><td>3mA</td></tr><tr><td>303</td><td>Rated AC residual operating current <span class="math">I_{\Delta n}</span> (UL2231-2)</td><td>20mA</td><td>20mA</td></tr><tr><td>304</td><td>Rated AC residual non-operating current <span class="math">I_{\Delta nc}</span> (UL2231-2)</td><td>15mA</td><td>15mA</td></tr><tr><td>305</td><td>Rated AC residual operating current <span class="math">I_{\Delta n}</span> (IEC 62752)</td><td>-</td><td>30mA</td></tr><tr><td>306</td><td>Rated AC residual non-operating current <span class="math">I_{\Delta nc}</span> (IEC 62752)</td><td>-</td><td>15mA</td></tr><tr><td>307</td><td>Electrical endurance</td><td>20,000</td><td>20,000</td></tr><tr><td>308</td><td>Rated operating temperature</td><td>-40~85 ℃</td><td>-40~85 ℃</td></tr><tr><td>309</td><td>Pollution degree</td><td>2</td><td>2</td></tr></tbody></table>

***

### 3. Residual Current Detection Characteristics

#### **PIN 3 (X6/X30 Output) - IEC 62955 / IEC 62752**

**Operating Current**

<table><thead><tr><th width="97.888916015625">#</th><th width="351.5556640625">Operating Current</th><th>PIN 3 (X6) @BRCS03C-U5</th><th>PIN 3 (X30) @BRCS03C-U6</th></tr></thead><tbody><tr><td>401</td><td>Smooth DC</td><td>4.0~6.0 mA</td><td>4.0~6.0 mA</td></tr><tr><td>402</td><td>DC rectified from 2 phases</td><td>4.0~7.0 mA</td><td>4.0~7.0 mA</td></tr><tr><td>403</td><td>DC rectified from 3 phases</td><td>4.0~6.2 mA</td><td>4.0~6.2 mA</td></tr><tr><td>404</td><td>Sinewave AC</td><td>-</td><td>22.0~28.0 mA</td></tr><tr><td>405</td><td>A0 pulsating DC</td><td>-</td><td>10.5~42.0 mA</td></tr><tr><td>406</td><td>A90 pulsating DC</td><td>-</td><td>7.5~42.0 mA</td></tr><tr><td>407</td><td>A135 pulsating DC</td><td>-</td><td>3.3~42.0 mA</td></tr></tbody></table>

**Operating Time**

<table><thead><tr><th width="104.5555419921875">#</th><th width="344.7777099609375">Response time</th><th>PIN 3 (X6) @BRCS03C-U5</th><th>PIN 3 (X30) @BRCS03C-U6</th></tr></thead><tbody><tr><td>501</td><td>Smooth DC 6mA</td><td>≤ 500 ms</td><td>≤ 500 ms</td></tr><tr><td>502</td><td>Smooth DC 60mA</td><td>≤ 200 ms</td><td>≤ 200 ms</td></tr><tr><td>503</td><td>Smooth DC 200mA</td><td>≤ 70 ms</td><td>≤ 70 ms</td></tr><tr><td>504</td><td>Smooth DC 300mA</td><td>-</td><td>≤ 20 ms</td></tr><tr><td>505</td><td>DC rectified from 2 phases 60mA</td><td>≤ 200 ms</td><td>≤ 200 ms</td></tr><tr><td>506</td><td>DC rectified from 2 phases 200mA</td><td>≤ 70 ms</td><td>≤ 70 ms</td></tr><tr><td>507</td><td>DC rectified from 2 phases 300mA</td><td>-</td><td>≤ 20 ms</td></tr><tr><td>508</td><td>DC rectified from 3 phases 60mA</td><td>≤ 200 ms</td><td>≤ 200 ms</td></tr><tr><td>509</td><td>DC rectified from 3 phases 200mA</td><td>≤ 70 ms</td><td>≤ 70 ms</td></tr><tr><td>510</td><td>DC rectified from 3 phases 300mA</td><td>-</td><td>≤ 20 ms</td></tr><tr><td>511</td><td>AC 30mA</td><td>> 10000 ms</td><td>≤ 80 ms</td></tr><tr><td>512</td><td>AC 60mA</td><td>> 300 ms</td><td>≤ 60 ms</td></tr><tr><td>513</td><td>AC 150mA</td><td>> 80 ms</td><td>≤ 20 ms</td></tr><tr><td>514</td><td>AC 5A</td><td>> 80 ms</td><td>≤ 20 ms</td></tr></tbody></table>

**PIN 4 (X20 Output) - UL2231-2 (CCID-20)**

**Operating Current**

<table><thead><tr><th width="103.111083984375">#</th><th>Operating Current</th><th>PIN 4 (X20 Output) @BRCS03C-U5/U6</th></tr></thead><tbody><tr><td>601</td><td>60Hz sinewave AC</td><td>15.0~20.0 mA</td></tr><tr><td>602</td><td>150Hz sinewave AC</td><td>15.0~34.5 mA</td></tr><tr><td>603</td><td>400Hz sinewave AC</td><td>15.0~69.6 mA</td></tr><tr><td>604</td><td>Smooth DC</td><td>20.0~56.0 mA</td></tr></tbody></table>

**Operating Time**

<table><thead><tr><th width="105.3333740234375">#</th><th>Response time</th><th>PIN 4 (X20 Output) @BRCS03C-U5/U6</th></tr></thead><tbody><tr><td>701</td><td>20mA AC residual current (60Hz)</td><td>≤ 500 ms</td></tr><tr><td>702</td><td>100mA AC residual current (60Hz)</td><td>≤ 20 ms</td></tr><tr><td>703</td><td>264mA AC residual current (60Hz)</td><td>≤ 15 ms</td></tr><tr><td>704</td><td>56mA smooth DC residual current</td><td>≤ 40 ms</td></tr><tr><td>705</td><td>100mA smooth DC residual current</td><td>≤ 20 ms</td></tr></tbody></table>

***

### 4. Application Notes

**Typical application diagram**

<p align="center">                BRCS03C-U5/U6                                            EV charging controller</p>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FPNfao3FdtDfUFgC6eAo1%2Fimage.png?alt=media&amp;token=aa2d2764-fb48-4256-9101-67e036c03b66" alt=""><figcaption></figcaption></figure>

Additional information

* **Ferrite beads** - such as `BLM21PG331SN1D` - are suggested to replace the L1 at some existing charging controller models. C3 might be added in case of limit 5V DC power supply. Please ensure the DC power supply to the 5V version sensor is within the range of **5VDC ± 3%**, so as to ensure the proper function of the sensor.
* **NPN transistors** are used internally at the Pin 3 and Pin 4 of the 5V version sensor, and the direct connection of Pin 3/4 to switching devices such as relays or contactors - is **NOT allowed**. $$V\_{ce}$$ and $$I\_c$$ of the NPN transistor inside the 5V version sensor are maximally **40V** and **50mA**.

**Self-test time chart**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FjSQPUhXeqYeTyXehkt05%2Fimage.png?alt=media&amp;token=aa6cad7a-d021-41cf-8aea-687fc1d59291" alt=""><figcaption></figcaption></figure>

* A self-test **excluding** offset calibration is activated if Pin 2 - Test is connected to GND for a period of **40ms to 130ms**.
* A self-test **including** offset calibration is activated if Pin 2 - Test is connected to GND for a period of **150ms to 1000ms**. *(Note:* $$t\_1$$ *is the response time for internally generated test current.)*

#### **Offset calibration time chart**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fbdc92WNUsiljs2LibH3W%2Fimage.png?alt=media&amp;token=f903a183-099d-4658-9c41-03c136cda92a" alt=""><figcaption></figcaption></figure>

An explicit offset calibration excluding self-test cycle is activated if Pin 2 - Test is connected to GND for a period of **2s to 3s**. An offset calibration can be activated at regular intervals (such as start-up) or after the occur of certain critical events (such as short circuit).

> ⚠️ **Attention**: During the offset calibration, **NO leakage current or any other current may flow through the device** and the relays/contactors must be open. Also, the power supply voltage at Pin 6 Vcc must be stay at **5VDC ± 3%**.

#### **Switching recovery level**

![](https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FavNokEGi12U8wU4RU5A9%2Fimage.png?alt=media\&token=d6518b2e-5987-471f-bfb3-b04a6c11e0d8)

If the trip-level $$I\_{\Delta T}$$ is accomplished the output will change their state from low-level to high level. Depending on the existence of the residual current $$I\_{\Delta}$$, the output will remain in this state until $$I\_{\Delta}$$ falls below the threshold $$I\_{\Delta R}$$.

* **X20 Pin (CCID20):** Typical values of $$I\_{\Delta T}$$ DC 26mA & AC 17.5mA; Typical value of $$I\_{\Delta R}$$ is 75%.
* **X30 Pin (IEC 62752):** Typical values of $$I\_{\Delta T}$$ DC 5mA & AC 24mA; Typical value of $$I\_{\Delta R}$$ is 75%.
* **X6 Pin (IEC 62955):** Typical values of $$I\_{\Delta T}$$ DC 5mA; Typical value of $$I\_{\Delta R}$$ is 75%.

***

### 5. Mechanical outline

BRCS03C-U5-L1 / BRCS03C-U6-L1:

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FZgFWxSyXM013M4Vr0QDQ%2Fimage.png?alt=media&amp;token=cf96f760-7112-4896-ab85-b3bd4b892227" alt=""><figcaption></figcaption></figure>

<table><thead><tr><th width="171.3333740234375">Model</th><th width="89.111083984375">Pin 1</th><th width="91.333251953125">Pin 2</th><th width="104.6666259765625">Pin 3</th><th width="118">Pin 4</th><th width="89.1109619140625">Pin 5</th><th width="99.111083984375">Pin 6</th></tr></thead><tbody><tr><td><strong>BRCS03C-U5-L1</strong></td><td>-</td><td>Test</td><td>DC fault (IEC 62955)</td><td>AC &#x26; DC fault (UL2231(CCID20))</td><td>GND</td><td>5V DC</td></tr><tr><td><strong>BRCS03C-U6-L1</strong></td><td>-</td><td>Test</td><td>AC &#x26; DC fault (IEC 62752)</td><td>AC &#x26; DC fault (UL2231(CCID20))</td><td>GND</td><td>5V DC</td></tr></tbody></table>

***

### 6. Ordering information

<table><thead><tr><th width="69.77783203125">#</th><th width="214">Order Number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td><strong>BRCS03C-U5-L1</strong></td><td><strong>BRCS03C Residual Current Sensor</strong><br>5V DC Interface, PCB-mount (Copper jumper)<br>UL2231-2(CCID20) &#x26; IEC62955, 32A<br>6 Pin, Pitch=1.9mm</td></tr><tr><td>2</td><td><strong>BRCS03C-U6-L1</strong></td><td><strong>BRCS03C Residual Current Sensor</strong><br>5V DC Interface, PCB-mount (Copper jumper)<br>UL2231-2(CCID20) &#x26; IEC62752, 32A<br>6 Pin, Pitch=1.9mm</td></tr></tbody></table>

***

#### 7. Additional Notes

> 🛑 **ESD Warning**: The sensor is susceptible to be damaged from an ESD event and the personnel should be grounded when handling it.

* Do **NOT** allow strong static electricity near the sensor, because static electricity can cause damage to the ICs inside the sensor. Take static electricity precautions when handling.
* Do **NOT** exceed 260°C for 10 seconds when soldering the sensors of PCB-mounting versions. This is the maximum heat resistance grade of these sensors.
* Do **NOT** solder the sensors with the central isolation cross installed. The central isolation cross can be installed after soldering the sensors.
* Do **NOT** drop the sensor or apply any other mechanical stress to the sensor, as such stresses may change performance characteristics.
* Please place the sensor with an appropriate distance from components that can generate high magnetic fields, such as relays or contactors, to ensure accurate residual current detection.


# BRCS03X - UL

## BRCS03X-U5/U6 - UL & IEC

{% hint style="info" %}
**Applies to:** BRCS03X-U5/U6 Residual Current Sensor (UL 2231-2 (CCID20) and IEC 62955 / IEC 62752) | **Last Updated:** 2026-09-28
{% endhint %}

### 1. Introduction

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2F1GE31HaHeD9EHfYer4SQ%2Fimage.png?alt=media&amp;token=a6a781cb-e4a6-41af-8843-eaf7e9c21716" alt=""><figcaption></figcaption></figure></div>

The BRCS03X-U5/BRCS03X-U6 is an AC/DC residual current sensor with two separate fault signal outputs – one Pin conforming to UL2231-2 (CCID20) and the other Pin conforming to IEC 62955 or IEC 62752. It can be used for built-in residual current protection system at AC charging stations.

* Digital outputs of fault detection conforming to UL2231-2 (CCID20) and IEC 62955 / IEC 62752
* Cost-effective solution of residual current detection for mode-2/3 EVSE
* Fast response time facilitating a broad selection of switching devices
* Accurate measurement and optimization against nuisance tripping

***

### 2. Technical Data

<table><thead><tr><th width="92.333251953125">#</th><th width="405.4444580078125">Technical Specification</th><th>BRCS03X-U5</th><th>BRCS03X-U6</th></tr></thead><tbody><tr><td>101</td><td>Rated current in monitoring circuit (1phase/3phase)</td><td>80A / 40A</td><td>80A / 40A</td></tr><tr><td>102</td><td>Rated frequency in monitoring circuit</td><td>60Hz</td><td>60Hz</td></tr><tr><td>103</td><td>Rated impulse withstand voltage in monitoring circuit</td><td>6kV</td><td>6kV</td></tr><tr><td>104</td><td>Over-voltage category in monitoring circuit</td><td>III</td><td>III</td></tr><tr><td>201</td><td>Rated operating voltage in control circuit, <span class="math">V_{cc}</span></td><td>5VDC ± 3%</td><td>5VDC ± 3%</td></tr><tr><td>202</td><td>Power consumption</td><td>&#x3C; 500mW</td><td>&#x3C; 500mW</td></tr><tr><td>203</td><td>Pin 1 – N.C.</td><td>Not connected</td><td>Not connected</td></tr><tr><td>204</td><td>Pin 2 – Test signal</td><td>Digital input</td><td>Digital input</td></tr><tr><td>205</td><td>Pin 3 – Fault signal: X6-IEC62955 (RDC-MD) or X30-IEC62752 (IC-CPD)</td><td>Digital output (RDC-MD)</td><td>Digital output (IC-CPD)</td></tr><tr><td>206</td><td>Pin 4 – Fault signal: X20-UL2231 (CCID20)</td><td>Digital output</td><td>Digital output</td></tr><tr><td>207</td><td>Pin 5 – GND</td><td>GND</td><td>GND</td></tr><tr><td>208</td><td>Pin 6 – Vcc for 5V</td><td>+5VDC</td><td>+5VDC</td></tr><tr><td>301</td><td>Rated DC residual operating current <span class="math">I_{\Delta dc}</span> (IEC 62955)</td><td>6mA</td><td>6mA</td></tr><tr><td>302</td><td>Rated DC residual non-operating current <span class="math">I_{\Delta ndc}</span> (IEC 62955)</td><td>3mA</td><td>3mA</td></tr><tr><td>303</td><td>Rated AC residual operating current <span class="math">I_{\Delta n}</span> (UL2231-2)</td><td>20mA</td><td>20mA</td></tr><tr><td>304</td><td>Rated AC residual non-operating current <span class="math">I_{\Delta nc}</span> (UL2231-2)</td><td>15mA</td><td>15mA</td></tr><tr><td>305</td><td>Rated AC residual operating current <span class="math">I_{\Delta n}</span> (IEC 62752)</td><td>-</td><td>30mA</td></tr><tr><td>306</td><td>Rated AC residual non-operating current <span class="math">I_{\Delta nc}</span> (IEC 62752)</td><td>-</td><td>15mA</td></tr><tr><td>307</td><td>Electrical endurance</td><td>20,000</td><td>20,000</td></tr><tr><td>308</td><td>Rated operating temperature</td><td>-40~85 ℃</td><td>-40~85 ℃</td></tr><tr><td>309</td><td>Pollution degree</td><td>2</td><td>2</td></tr></tbody></table>

***

### 3. Residual Current Detection Characteristics

#### **PIN 3 (X6/X30 Output) - IEC 62955 / IEC 62752**

**Operating Current**

<table><thead><tr><th width="97.888916015625">#</th><th width="396.666748046875">Operating Current</th><th>PIN 3 (X6) @BRCS03X-U5</th><th>PIN 3 (X30) @BRCS03X-U6</th></tr></thead><tbody><tr><td>401</td><td>Smooth DC</td><td>4.0~6.0 mA</td><td>4.0~6.0 mA</td></tr><tr><td>402</td><td>DC rectified from 2 phases</td><td>4.0~7.0 mA</td><td>4.0~7.0 mA</td></tr><tr><td>403</td><td>DC rectified from 3 phases</td><td>4.0~6.2 mA</td><td>4.0~6.2 mA</td></tr><tr><td>404</td><td>Sinewave AC</td><td>-</td><td>22.0~28.0 mA</td></tr><tr><td>405</td><td>A0 pulsating DC</td><td>-</td><td>10.5~42.0 mA</td></tr><tr><td>406</td><td>A90 pulsating DC</td><td>-</td><td>7.5~42.0 mA</td></tr><tr><td>407</td><td>A135 pulsating DC</td><td>-</td><td>3.3~42.0 mA</td></tr></tbody></table>

**Operating Time**

<table><thead><tr><th width="96.77783203125">#</th><th width="380.4444580078125">Response time</th><th>PIN 3 (X6) @BRCS03X-U5</th><th>PIN 3 (X30) @BRCS03X-U6</th></tr></thead><tbody><tr><td>501</td><td>Smooth DC 6mA</td><td>≤ 500 ms</td><td>≤ 500 ms</td></tr><tr><td>502</td><td>Smooth DC 60mA</td><td>≤ 200 ms</td><td>≤ 200 ms</td></tr><tr><td>503</td><td>Smooth DC 200mA</td><td>≤ 70 ms</td><td>≤ 70 ms</td></tr><tr><td>504</td><td>Smooth DC 300mA</td><td>-</td><td>≤ 20 ms</td></tr><tr><td>505</td><td>DC rectified from 2 phases 60mA</td><td>≤ 200 ms</td><td>≤ 200 ms</td></tr><tr><td>506</td><td>DC rectified from 2 phases 200mA</td><td>≤ 70 ms</td><td>≤ 70 ms</td></tr><tr><td>507</td><td>DC rectified from 2 phases 300mA</td><td>-</td><td>≤ 20 ms</td></tr><tr><td>508</td><td>DC rectified from 3 phases 60mA</td><td>≤ 200 ms</td><td>≤ 200 ms</td></tr><tr><td>509</td><td>DC rectified from 3 phases 200mA</td><td>≤ 70 ms</td><td>≤ 70 ms</td></tr><tr><td>510</td><td>DC rectified from 3 phases 300mA</td><td>-</td><td>≤ 20 ms</td></tr><tr><td>511</td><td>AC 30mA</td><td>> 10000 ms</td><td>≤ 80 ms</td></tr><tr><td>512</td><td>AC 60mA</td><td>> 300 ms</td><td>≤ 60 ms</td></tr><tr><td>513</td><td>AC 150mA</td><td>> 80 ms</td><td>≤ 20 ms</td></tr><tr><td>514</td><td>AC 5A</td><td>> 80 ms</td><td>≤ 20 ms</td></tr></tbody></table>

#### **PIN 4 (X20 Output) - UL2231-2 (CCID-20)**

**Operating Current**

<table><thead><tr><th width="97.5555419921875">#</th><th width="370">Operating Current</th><th>PIN 4 (X20 Output) @BRCS03X-U5/U6</th></tr></thead><tbody><tr><td>601</td><td>60Hz sinewave AC</td><td>15.0~20.0 mA</td></tr><tr><td>602</td><td>150Hz sinewave AC</td><td>15.0~34.5 mA</td></tr><tr><td>603</td><td>400Hz sinewave AC</td><td>15.0~69.6 mA</td></tr><tr><td>604</td><td>Smooth DC</td><td>20.0~56.0 mA</td></tr></tbody></table>

**Operating Time**

<table><thead><tr><th width="103.1112060546875">#</th><th width="365.888916015625">Response time</th><th>PIN 4 (X20 Output) @BRCS03X-U5/U6</th></tr></thead><tbody><tr><td>701</td><td>20mA AC residual current (60Hz)</td><td>≤ 500 ms</td></tr><tr><td>702</td><td>100mA AC residual current (60Hz)</td><td>≤ 20 ms</td></tr><tr><td>703</td><td>264mA AC residual current (60Hz)</td><td>≤ 15 ms</td></tr><tr><td>704</td><td>56mA smooth DC residual current</td><td>≤ 40 ms</td></tr><tr><td>705</td><td>100mA smooth DC residual current</td><td>≤ 20 ms</td></tr></tbody></table>

***

### 4. Application Notes

**Typical application diagram**

<p align="center">                         BRCS03X-U5/U6                                              EV charging controller</p>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FIkrkjzyCOS7cxuCnYJpi%2Fimage.png?alt=media&amp;token=c667cb91-22e3-4385-b5d0-67b6e2adec7d" alt=""><figcaption></figcaption></figure>

Additional information

* **Ferrite beads** - such as `BLM21PG331SN1D` - are suggested to replace the L1 at some existing charging controller models. C3 might be added in case of limit 5V DC power supply. Please ensure the DC power supply to the 5V version sensor is within the range of **5VDC ± 3%**, so as to ensure the proper function of the sensor.
* **NPN transistors** are used internally at the Pin 3 and Pin 4 of the 5V version sensor, and the direct connection of Pin 3/4 to switching devices such as relays or contactors - is **NOT allowed**. $$V\_{ce}$$ and $$I\_c$$ of the NPN transistor inside the 5V version sensor are maximally **40V** and **50mA**.

#### **Self-test time chart**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FGOGUaob7AiuOxmshsTp2%2Fimage.png?alt=media&amp;token=8e871dfa-be2d-4981-a2d3-0e166909cc8b" alt=""><figcaption></figcaption></figure>

* A self-test **excluding** offset calibration is activated if Pin 2 - Test is connected to GND for a period of **40ms to 130ms**.
* A self-test **including** offset calibration is activated if Pin 2 - Test is connected to GND for a period of **150ms to 1000ms**. *(Note:* $$t\_1$$ *is the response time for internally generated test current.)*

#### **Offset calibration time chart**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FDtTZT4BaRODvvvqDf9SS%2Fimage.png?alt=media&amp;token=1c1dfc0b-0f74-4ac4-8db0-6f7e6ff1fa2b" alt=""><figcaption></figcaption></figure>

An explicit offset calibration excluding self-test cycle is activated if Pin 2 - Test is connected to GND for a period of **2s to 3s**. An offset calibration can be activated at regular intervals (such as start-up) or after the occur of certain critical events (such as short circuit).

> ⚠️ **Attention**: During the offset calibration, **NO leakage current or any other current may flow through the device** and the relays/contactors must be open. Also, the power supply voltage at Pin 6 Vcc must be stay at **5VDC ± 3%**.

#### **Switching recovery level**

![](https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FEf0DHKyFlRJFw5vVauMM%2Fimage.png?alt=media\&token=2170cdf3-46b5-477c-9d72-1ededa23cf12)

If the trip-level $$I\_{\Delta T}$$ is accomplished the output will change their state from low-level to high level. Depending on the existence of the residual current $$I\_{\Delta}$$, the output will remain in this state until $$I\_{\Delta}$$ falls below the threshold $$I\_{\Delta R}$$.

* **X20 Pin (CCID20):** Typical values of $$I\_{\Delta T}$$ DC 26mA & AC 17.5mA; Typical value of $$I\_{\Delta R}$$ is 75%.
* **X30 Pin (IEC 62752):** Typical values of $$I\_{\Delta T}$$ DC 5mA & AC 24mA; Typical value of $$I\_{\Delta R}$$ is 75%.
* **X6 Pin (IEC 62955):** Typical values of $$I\_{\Delta T}$$ DC 5mA; Typical value of $$I\_{\Delta R}$$ is 75%.

***

### 5. Mechanical outline

BRCS03X-U5-L2 / BRCS03X-U6-L2:

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FOJLE1r2GN2bytwEHJo6J%2Fimage.png?alt=media&amp;token=da726ef5-2c04-4092-90f8-7f1fb7004348" alt=""><figcaption></figcaption></figure>

<table><thead><tr><th width="188">Model</th><th width="95.77783203125">Pin 1</th><th width="105.77783203125">Pin 2</th><th width="122.4444580078125">Pin 3</th><th width="118">Pin 4</th><th width="94.6666259765625">Pin 5</th><th width="109.111083984375">Pin 6</th></tr></thead><tbody><tr><td><strong>BRCS03X-U5-L2</strong></td><td>-</td><td>Test</td><td>DC fault (IEC 62955)</td><td>AC &#x26; DC fault (UL2231(CCID20))</td><td>GND</td><td>5V DC</td></tr><tr><td><strong>BRCS03X-U6-L2</strong></td><td>-</td><td>Test</td><td>AC &#x26; DC fault (IEC 62752)</td><td>AC &#x26; DC fault (UL2231(CCID20))</td><td>GND</td><td>5V DC</td></tr></tbody></table>

***

### 6. Ordering information

<table><thead><tr><th width="75.3333740234375">#</th><th width="223.2222900390625">Order Number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td><strong>BRCS03X-U5-L2</strong></td><td><strong>BRCS03X Residual Current Sensor</strong><br>5V DC Interface, PCB-mount (Through hole)<br>UL2231-2(CCID20) &#x26; IEC62955, 1P+N(80A) / 3P+N(40A)<br>6 Pin, Pitch=1.9mm</td></tr><tr><td>2</td><td><strong>BRCS03X-U6-L2</strong></td><td><strong>BRCS03X Residual Current Sensor</strong><br>5V DC Interface, PCB-mount (Through hole)<br>UL2231-2(CCID20) &#x26; IEC62752, 1P+N(80A) / 3P+N(40A)<br>6 Pin, Pitch=1.9mm</td></tr></tbody></table>

***

### 7. Additional Notes

> 🛑 **ESD Warning**: The sensor is susceptible to be damaged from an ESD event and the personnel should be grounded when handling it.

* Do **NOT** allow strong static electricity near the sensor, because static electricity can cause damage to the ICs inside the sensor. Take static electricity precautions when handling.
* Do **NOT** exceed 260°C for 10 seconds when soldering the sensors of PCB-mounting versions. This is the maximum heat resistance grade of these sensors.
* Do **NOT** drop the sensor or apply any other mechanical stress to the sensor, as such stresses may change performance characteristics.
* Please place the sensor with an appropriate distance from components that can generate high magnetic fields, such as relays or contactors, to ensure accurate residual current detection.


# BRCS01V - UL

## BRCS01V-U5/U6 - UL & IEC

{% hint style="info" %}
**Applies to:** BRCS01V-U5/U6 Residual Current Sensor (UL 2231-2 (CCID20) and IEC 62955 / IEC 62752) | **Last Updated:** 2026-09-28
{% endhint %}

### 1. Introduction

<div align="left"><figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FAcIKxkhJjj7U9mWmrEVF%2Fimage.png?alt=media&amp;token=a59a2679-1102-48e6-81bc-82f11622a169" alt=""><figcaption></figcaption></figure></div>

The BRCS01V-U5/U6 is an AC/DC residual current sensor with two separate fault signal outputs – one Pin conforming to UL2231-2 (CCID20) and the other Pin conforming to IEC 62955 or IEC 62752. It can be used for built-in residual current protection system at AC charging stations.

* Digital outputs of fault detection conforming to UL2231-2 (CCID20) and IEC 62955 / IEC 62752
* Cost-effective solution of residual current detection for mode-2/3 EVSE
* Fast response time facilitating a broad selection of switching devices
* Accurate measurement and optimization against nuisance tripping

***

### 2. Technical Data

<table><thead><tr><th width="85.666748046875">#</th><th width="380.6666259765625">Technical Specification</th><th>BRCS01V-U5</th><th>BRCS01V-U6</th></tr></thead><tbody><tr><td>101</td><td>Rated current in monitoring circuit (1phase/3phase)</td><td>80A / 40A</td><td>80A / 40A</td></tr><tr><td>102</td><td>Rated frequency in monitoring circuit</td><td>60Hz</td><td>60Hz</td></tr><tr><td>103</td><td>Rated impulse withstand voltage in monitoring circuit</td><td>6kV</td><td>6kV</td></tr><tr><td>104</td><td>Over-voltage category in monitoring circuit</td><td>III</td><td>III</td></tr><tr><td>201</td><td>Rated operating voltage in control circuit, <span class="math">V_{cc}</span></td><td>5VDC ± 3%</td><td>5VDC ± 3%</td></tr><tr><td>202</td><td>Power consumption</td><td>&#x3C; 500mW</td><td>&#x3C; 500mW</td></tr><tr><td>203</td><td>Pin 1 – Vcc for 5V</td><td>+5VDC</td><td>+5VDC</td></tr><tr><td>204</td><td>Pin 2 – Trip signal: X20-UL2231 (CCID20)</td><td>Digital output</td><td>Digital output</td></tr><tr><td>205</td><td>Pin 3 – GND</td><td>GND</td><td>GND</td></tr><tr><td>206</td><td>Pin 4 – Trip signal: X6-IEC62955 (RDC-MD) or X30-IEC62752 (IC-CPD)</td><td>Digital output (RDC-MD)</td><td>Digital output (IC-CPD)</td></tr><tr><td>207</td><td>Pin 5 – Test signal</td><td>Digital input</td><td>Digital input</td></tr><tr><td>301</td><td>Rated DC residual operating current <span class="math">I_{\Delta dc}</span> (IEC 62955)</td><td>6mA</td><td>6mA</td></tr><tr><td>302</td><td>Rated DC residual non-operating current <span class="math">I_{\Delta ndc}</span> (IEC 62955)</td><td>3mA</td><td>3mA</td></tr><tr><td>303</td><td>Rated AC residual operating current <span class="math">I_{\Delta n}</span> (UL2231-2)</td><td>20mA</td><td>20mA</td></tr><tr><td>304</td><td>Rated AC residual non-operating current <span class="math">I_{\Delta nc}</span> (UL2231-2)</td><td>15mA</td><td>15mA</td></tr><tr><td>305</td><td>Rated AC residual operating current <span class="math">I_{\Delta n}</span> (IEC 62752)</td><td>-</td><td>30mA</td></tr><tr><td>306</td><td>Rated AC residual non-operating current <span class="math">I_{\Delta nc}</span> (IEC 62752)</td><td>-</td><td>15mA</td></tr><tr><td>307</td><td>Electrical endurance</td><td>20,000</td><td>20,000</td></tr><tr><td>308</td><td>Rated operating temperature</td><td>-40~85 ℃</td><td>-40~85 ℃</td></tr><tr><td>309</td><td>Pollution degree</td><td>2</td><td>2</td></tr></tbody></table>

***

### 3. Residual Current Detection Characteristics

#### **PIN 4 (X6/X30 Output) - IEC 62955 / IEC 62752**

**Operating Current**

<table><thead><tr><th width="93.4444580078125">#</th><th width="367.6666259765625">Operating Current</th><th>PIN 4 (X6) @BRCS01V-U5</th><th>PIN 4 (X30) @BRCS01V-U6</th></tr></thead><tbody><tr><td>401</td><td>Smooth DC</td><td>4.0~6.0 mA</td><td>4.0~6.0 mA</td></tr><tr><td>402</td><td>DC rectified from 2 phases</td><td>4.0~7.0 mA</td><td>4.0~7.0 mA</td></tr><tr><td>403</td><td>DC rectified from 3 phases</td><td>4.0~6.2 mA</td><td>4.0~6.2 mA</td></tr><tr><td>404</td><td>Sinewave AC</td><td>-</td><td>22.0~28.0 mA</td></tr><tr><td>405</td><td>A0 pulsating DC</td><td>-</td><td>10.5~42.0 mA</td></tr><tr><td>406</td><td>A90 pulsating DC</td><td>-</td><td>7.5~42.0 mA</td></tr><tr><td>407</td><td>A135 pulsating DC</td><td>-</td><td>3.3~42.0 mA</td></tr></tbody></table>

**Operating Time**

<table><thead><tr><th width="93.4444580078125">#</th><th width="364.333251953125">Response time</th><th>PIN 4 (X6) @BRCS01V-U5</th><th>PIN 4 (X30) @BRCS01V-U6</th></tr></thead><tbody><tr><td>501</td><td>Smooth DC 6mA</td><td>≤ 500 ms</td><td>≤ 500 ms</td></tr><tr><td>502</td><td>Smooth DC 60mA</td><td>≤ 200 ms</td><td>≤ 200 ms</td></tr><tr><td>503</td><td>Smooth DC 200mA</td><td>≤ 70 ms</td><td>≤ 70 ms</td></tr><tr><td>504</td><td>Smooth DC 300mA</td><td>-</td><td>≤ 20 ms</td></tr><tr><td>505</td><td>DC rectified from 2 phases 60mA</td><td>≤ 200 ms</td><td>≤ 200 ms</td></tr><tr><td>506</td><td>DC rectified from 2 phases 200mA</td><td>≤ 70 ms</td><td>≤ 70 ms</td></tr><tr><td>507</td><td>DC rectified from 2 phases 300mA</td><td>-</td><td>≤ 20 ms</td></tr><tr><td>508</td><td>DC rectified from 3 phases 60mA</td><td>≤ 200 ms</td><td>≤ 200 ms</td></tr><tr><td>509</td><td>DC rectified from 3 phases 200mA</td><td>≤ 70 ms</td><td>≤ 70 ms</td></tr><tr><td>510</td><td>DC rectified from 3 phases 300mA</td><td>-</td><td>≤ 20 ms</td></tr><tr><td>511</td><td>AC 30mA</td><td>> 10000 ms</td><td>≤ 80 ms</td></tr><tr><td>512</td><td>AC 60mA</td><td>> 300 ms</td><td>≤ 60 ms</td></tr><tr><td>513</td><td>AC 150mA</td><td>> 80 ms</td><td>≤ 20 ms</td></tr><tr><td>514</td><td>AC 5A</td><td>> 80 ms</td><td>≤ 20 ms</td></tr></tbody></table>

#### **PIN 2 (X20 Output) - UL2231-2 (CCID-20)**

**Operating Current**

<table><thead><tr><th width="98.6666259765625">#</th><th width="344.5555419921875">Operating Current</th><th>PIN 2 (X20) @BRCS01V-U5/U6</th></tr></thead><tbody><tr><td>601</td><td>60Hz sinewave AC</td><td>15.0~20.0 mA</td></tr><tr><td>602</td><td>150Hz sinewave AC</td><td>15.0~34.5 mA</td></tr><tr><td>603</td><td>400Hz sinewave AC</td><td>15.0~69.6 mA</td></tr><tr><td>604</td><td>Smooth DC</td><td>20.0~56.0 mA</td></tr></tbody></table>

**Operating Time**

<table><thead><tr><th width="103.111083984375">#</th><th width="347">Response time</th><th>PIN 2 (X20) @BRCS01V-U5/U6</th></tr></thead><tbody><tr><td>701</td><td>20mA AC residual current (60Hz)</td><td>≤ 500 ms</td></tr><tr><td>702</td><td>100mA AC residual current (60Hz)</td><td>≤ 20 ms</td></tr><tr><td>703</td><td>264mA AC residual current (60Hz)</td><td>≤ 15 ms</td></tr><tr><td>704</td><td>56mA smooth DC residual current</td><td>≤ 40 ms</td></tr><tr><td>705</td><td>100mA smooth DC residual current</td><td>≤ 20 ms</td></tr></tbody></table>

***

### 4. Application Notes

**Typical application diagram**

<p align="center">BRCS01V version                                                    EV charging controller</p>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FgzDd3X8md4eaaKaoqX53%2Fimage.png?alt=media&amp;token=d2fc9260-259b-4542-9473-bcc1315582df" alt=""><figcaption></figcaption></figure>

Additional information

* **Vcc Pin (Power supply pin):** The power supply voltage range to the sensor is **4.85 - 5.15 VDC**, and the power ripple is not higher than **150mV**. Ferrite beads and filter capacitors are suggested to be placed close to the Vcc pin. In addition, a LDO - such as `LP2985A-50DBV` - is strongly recommended to be used at the charging controller side.
* **Trip Pins (Fault signal output pin):** When residual current in the circuit exceeds the threshold, the output level changes from low to high. Suggest adding ferrite beads and filter capacitors close to this pin. A direct connection of Pin 2/4 to switching devices - such as relays or contactors - is **NOT allowed**. The trip signal of Pin 2/4 is suggested to be monitored by the charging controller MCU.
* **TEST Pin (Self-test input pin):** Before starting every charging, this pin is used to perform a simulated test to verify whether the sensor functions correctly.

#### **Self-test time chart**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2F8lGgv5upSDpGuHihPzHA%2Fimage.png?alt=media&amp;token=9038ac10-099f-4c57-9274-e19f0e2c3005" alt=""><figcaption></figcaption></figure>

* A self-test **excluding** offset calibration is activated if Pin 5 - Test is connected to GND for a period of **40ms to 130ms**.
* A self-test **including** offset calibration is activated if Pin 5 - Test is connected to GND for a period of **150ms to 1000ms**. *(Note:* $$t\_1$$ *is the response time for internally generated test current.)*

#### **Offset calibration time  chart**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Fq91ErSIitGbe82JNEcfc%2Fimage.png?alt=media&amp;token=a53a9b53-deec-4236-a82f-e1c25acfd6f0" alt=""><figcaption></figcaption></figure>

An explicit offset calibration excluding self-test cycle is activated if Pin 5 - Test is connected to GND for a period of **2s to 3s**. An offset calibration can be activated at regular intervals (such as start-up) or after the occur of certain critical events (such as short circuit).

> ⚠️ **Attention**: During the offset calibration, **NO leakage current or any other current may flow through the device** and the relays/contactors must be open. Also, the power supply voltage at Pin 1 Vcc must be stay at **5VDC ± 3%**.

#### **Switching recovery level**

![](https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FiM8NQ6QUeV7vuQ4jo2P2%2Fimage.png?alt=media\&token=5224c283-8d73-4e60-8f08-d40346916437)

If the trip-level $$I\_{\Delta T}$$ is accomplished the output will change their state from low-level to high level. Depending on the existence of the residual current $$I\_{\Delta}$$, the output will remain in this state until $$I\_{\Delta}$$ falls below the threshold $$I\_{\Delta R}$$.

* **X20 Pin (CCID20):** Typical values of $$I\_{\Delta T}$$ DC 26mA & AC 17.5mA; Typical value of $$I\_{\Delta R}$$ is 75%.
* **X30 Pin (IEC 62752):** Typical values of $$I\_{\Delta T}$$ DC 5mA & AC 24mA; Typical value of $$I\_{\Delta R}$$ is 75%.
* **X6 Pin (IEC 62955):** Typical values of $$I\_{\Delta T}$$ DC 5mA; Typical value of $$I\_{\Delta R}$$ is 75%.

***

### 5. Mechanical outline

BRCS01V-U5/U6-S:

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FCNT3e3agXBI2h7xrAzUd%2Fimage.png?alt=media&amp;token=52aa0a7c-7fa2-4fd1-ade3-34d796a2f017" alt=""><figcaption></figcaption></figure>

<table><thead><tr><th width="176.888916015625">Model</th><th width="108">Pin 1</th><th width="130.2222900390625">Pin 2</th><th width="96.8890380859375">Pin 3</th><th width="120.2222900390625">Pin 4</th><th>Pin 5</th></tr></thead><tbody><tr><td><strong>BRCS01V-U5-S1</strong></td><td>5V DC</td><td>AC &#x26; DC fault (UL2231(CCID20))</td><td>GND</td><td>DC fault (IEC 62955)</td><td>Test</td></tr><tr><td><strong>BRCS01V-U6-S1</strong></td><td>5V DC</td><td>AC &#x26; DC fault (UL2231(CCID20))</td><td>GND</td><td>AC &#x26; DC fault (IEC 62752)</td><td>Test</td></tr></tbody></table>

***

### 6. Ordering information

<table><thead><tr><th width="70.8887939453125">#</th><th width="190.2222900390625">Order Number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td><strong>BRCS01V-U5-S1</strong></td><td>BRCS01V Residual Current Sensor, 5V DC<br>UL2231-2(CCID20) &#x26; IEC62955</td></tr><tr><td>2</td><td><strong>BRCS01V-U6-S1</strong></td><td>BRCS01V Residual Current Sensor, 5V DC<br>UL2231-2(CCID20) &#x26; IEC62752</td></tr></tbody></table>

***

### 7. Additional Notes

> 🛑 **ESD Warning**: The sensor is susceptible to be damaged from an ESD event and the personnel should be grounded when handling it.

* Do **NOT** allow strong static electricity near the sensor, because static electricity can cause damage to the ICs inside the sensor. Take static electricity precautions when handling.
* Do **NOT** exceed 260°C for 10 seconds when soldering the sensors of PCB-mounting versions. This is the maximum heat resistance grade of these sensors.
* Do **NOT** drop the sensor or apply any other mechanical stress to the sensor, as such stresses may change performance characteristics.
* Please place the sensor with an appropriate distance from components that can generate high magnetic fields, such as relays or contactors, to ensure accurate residual current detection.


# BSCT (CT Clamp)

## BSCT Series Split-Core Current Transformers (CT Clamps)

The **BSCT Series** split-core current transformers (CTs) are designed for fast and easy installation without disconnecting the primary conductor. They are ideal for retrofitting existing electrical panels, energy management systems (EMS), smart grid applications, and IoT power monitoring.

Originally prepared for our SDM series energy meters, these premium split-core CTs are now available as standalone standard products for global customers.&#x20;

Leveraging our deep expertise in magnetic component design and supply chain management, we deliver these CTs at exceptional market-leading performance. Furthermore, every single unit undergoes **100% accuracy testing (ratio & phase error)**, and customers can request access to their specific test data.

***

### Model Selection Guide

The table below lists the standard split-core CTs commonly used with our SDM series, which are also available for individual purchase.  While we highly recommend using the following models, custom specifications are available upon request.\ <br>

<table><thead><tr><th width="224">Model</th><th width="106.39990234375">Aperture (mm)</th><th>Shell Color</th><th width="127.2000732421875">Dimensions (A*B*C, mm)</th><th width="113.60009765625">Mounting Wings</th><th>Datasheet</th></tr></thead><tbody><tr><td>BSCT-10C 50A/16.6mA</td><td>10</td><td>Black</td><td><em>23 x 41 x 26</em></td><td>No</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BSCT-10C-50A16.6mA_Datasheet_EN.pdf" class="button primary">Download</a></td></tr><tr><td>BSCT-16B 120A/40mA</td><td>16</td><td>Black</td><td><em>30 x 47 x 32</em></td><td>No</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BSCT-16B-120A40mA_Datasheet_EN.pdf" class="button primary">Download</a></td></tr><tr><td>BSCT-16C 120A/40mA</td><td>16</td><td>Black</td><td><em>30 x 47 x 32</em></td><td>No</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BSCT-16C-120A40mA_Datasheet_EN.pdf" class="button primary">Download</a></td></tr><tr><td>BSCT-24C 300A/50mA</td><td>24</td><td>Black</td><td><em>45 x 70 x 37</em></td><td>Yes</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BSCT-24C-300A50mA_Datasheet_EN.pdf" class="button primary">Download</a></td></tr><tr><td>BSCT-36C 400A/66.6mA</td><td>36</td><td>Black</td><td><em>56 x 84 x 40</em></td><td>Yes</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BSCT-36C-400A66.6mA_Datasheet_EN.pdf" class="button primary">Download</a></td></tr></tbody></table>

Dimensional references are shown in the diagrams below.<br>

{% columns %}
{% column %}

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FoueDx6yjtFq3riyUU1J6%2FBSCT-xC-Lines.png?alt=media&amp;token=4bdeafb0-5964-405b-a182-6a5405855409" alt=""><figcaption></figcaption></figure>

<p align="center"><strong>Products without Mounting Wings (Apertures 20mm and below)</strong></p>
{% endcolumn %}

{% column %}

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FKonECykxQqOLvFUApKMf%2FBSCT-xC-Lines-with-hook.png?alt=media&amp;token=62a0bc28-2637-4113-9526-233592449fc8" alt=""><figcaption></figcaption></figure>

<p align="center"><strong>Products with Mounting Wings (Apertures 24mm and above)</strong></p>
{% endcolumn %}
{% endcolumns %}

\ <br>


# Discontinued Products

## Discontinued Products

{% hint style="warning" %}
**Notice:** The products and components listed on this page are no longer manufactured or sold. Their documentation is preserved here for existing users. For new projects, please refer to the recommended successor products.
{% endhint %}

***

### Electrical Monitoring Devices

<details>

<summary><strong>DC6-C2 RDC-MD</strong></summary>

* [Datasheet (PDF)](https://downloads.bituo-technik.com/Datasheet/Discontinued-Products/DC6-RDC-MD_Datasheet_EN.pdf)

</details>

<details>

<summary><strong>BRCM01 (RDC-MD, 12V)</strong></summary>

* [Datasheet (PDF)](https://downloads.bituo-technik.com/Datasheet/Discontinued-Products/BRCM01_Datasheet_EN.pdf)

</details>

### Electrical Measurement Components

<details>

<summary><strong>BRCS02C 2-in-1 Sensor - AC/DC Residual Current Detection &#x26; Current Transformer</strong></summary>

* [Datasheet (PDF)](https://downloads.bituo-technik.com/Datasheet/Discontinued-Products/BRCS02C_Datasheet_EN.pdf)

</details>

<details>

<summary><strong>BRCS02 AC/DC Residual Current Sensor</strong></summary>

* [Datasheet (PDF)](https://downloads.bituo-technik.com/Datasheet/Discontinued-Products/BRCS02_Datasheet_EN.pdf)

</details>

### Others

<details>

<summary><strong>eFAB RCBO (RDC-PD, 1P+N)</strong></summary>

* [Datasheet (PDF)](https://downloads.bituo-technik.com/Datasheet/Discontinued-Products/eFAB-Type-EV-RCBO_EN.pdf)

</details>

### 💬 Need Help?

{% hint style="info" %}
If you need assistance migrating from a discontinued product to a newer model, or require documentation not listed here, please contact our support team.
{% endhint %}


# SDM01 G2X & Combo Gen2 — EV Charger DLB Integration Guide

A complete technical guide to integrate the SDM01 Combo Gen2 and SDM01 G2X smart meters via Wi-Fi for Dynamic Load Balancing (DLB)

{% hint style="info" %}
**Status:** Active| **Applies to:** SDM01 G2X and SDM01 Combo Gen2 | **Firmware:** V10+  | **Audience:** EV Charger Product Managers & Firmware Engineers| **Last Updated:** 2026-08-01
{% endhint %}

***

### TL;DR — Quick Decision Card

```
What is your target DLB polling interval?

≤ 1 second (high-frequency, fastest response)
└── Raw UDP / UDP AES  ← Strongly recommended
    Push-based, zero connection overhead, lowest latency
    See Section 5.1

1–5 seconds (mid-frequency, covers most residential DLB use cases)
├── Raw UDP (still the simplest option)
├── HTTP polling (if your MCU already has an HTTP client stack)
└── Modbus TCP (if you have an existing Modbus stack)
    ⚠️ Single-connection limit — see Section 5.2 warning

> 5 seconds (low-frequency monitoring / energy logging)
└── HTTP polling (simplest, same JSON format as UDP)
    See Section 5.4

Configuration writes (one-shot)
├── HTTP POST  ← Primary local channel
│   See Section 5.4
├── MQTT       ← Cloud / remote configuration
└── BLE API    ← Local mobile configuration (BT Powerlink app or custom app)

Security compliance required (EN 18031)?
├── UDP AES (encrypted push, maintains low latency)  ← Recommended
└── WSS or Modbus TCP over TLS
    ⚠️ Pro firmware: max 2 concurrent TLS connections total recommended
    See Section 5.3 & 5.5

Multi-charger setup?
└── See Annex A for architecture options
   (Centralized Arbiter / OCPP Cloud Coordination)
```

***

### 1. Purpose & Scope

This guide helps EV charger **product managers** and **firmware/embedded engineers** integrate the [SDM01 G2X](https://docs.bituo-technik.com/product-document/sdm-series/sdm01-g2x) and [SDM01 Combo Gen2](https://docs.bituo-technik.com/product-document/sdm-series/sdm01-combo-gen2) smart energy meters into an EV charging system over a local Wi-Fi/LAN network to implement **Dynamic Load Balancing (DLB)** — also known as anti-tripping or load management.

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2F4RAt3qjGdLFxUsDfgnhb%2Fimage.png?alt=media&amp;token=d7349cff-be11-492a-808f-f29828fd2093" alt=""><figcaption></figcaption></figure>

**What DLB does:** By continuously monitoring the total grid import current ($$I\_{grid}$$) at the home's main incomer, the EV charger dynamically adjusts its charging current so that the total household load never exceeds the main circuit breaker rating ($$I\_{max}$$), preventing nuisance tripping.

**What this guide covers:**

* System architecture and control flow
* Electrical installation reference
* Wi-Fi provisioning and device discovery
* Communication protocol selection (Raw UDP, HTTP, Modbus TCP, MQTT, WSS)
* DLB closed-loop control logic and fail-safe design
* Testing and validation checklist
* Advanced: Multi-charger DLB and HEMS integration
* Advanced: Custom ESP32-C6 firmware development

***

### 2. System Architecture Overview

#### 2.1 Control Flow

<table><thead><tr><th width="167">Step</th><th width="239">Actor</th><th>Action</th></tr></thead><tbody><tr><td><strong>① Provision</strong></td><td>User / Installer</td><td>Configure meter Wi-Fi via BLE (BT Powerlink app or custom app via BLE API)</td></tr><tr><td><strong>② Discover</strong></td><td>EV Charger (Main MCU)</td><td>Auto-discover meter IP on LAN via mDNS</td></tr><tr><td><strong>③ Communicate</strong></td><td>EV Charger (Main MCU)</td><td>Receive high-frequency UDP pushes (or poll via Modbus TCP / HTTP)</td></tr><tr><td><strong>④ Control</strong></td><td>EV Charger (Main MCU)</td><td>Run DLB closed-loop algorithm, adjust PWM duty cycle</td></tr><tr><td><strong>⑤ Fail-Safe</strong></td><td>EV Charger (Main MCU)</td><td>On comms timeout, immediately ramp down to safe current</td></tr></tbody></table>

> 💡 **Configuring the UDP target address:** The meter needs to know which IP:Port to push UDP data to. This can be configured via any of the following channels:
>
> * **LAN HTTP** — `POST http://<meter-ip>/save-config` with `{"cmd":"udp","IpAddress":"<charger-ip>","localUdpPort":<port>}` from the charger MCU or any LAN client
> * **BLE** — via BT Powerlink app or your own app using the BLE Secured API (local, no internet required)
> * **Cloud MQTT** — via your app → cloud MQTT broker → meter (requires meter to be online)

#### 2.2 Key Parameters

<table><thead><tr><th width="123">Symbol</th><th width="444">Description</th><th>Typical Value</th></tr></thead><tbody><tr><td><span class="math">I_{max}</span></td><td>Main circuit breaker rating (set by user)</td><td>e.g. 60 A</td></tr><tr><td><span class="math">I_{safe}</span></td><td>Safety headroom (10–20% of <span class="math">I_{max}</span>)</td><td>e.g. 6 A</td></tr><tr><td><span class="math">I_{grid}</span></td><td>Real-time total grid import current (from meter)</td><td>Live reading</td></tr><tr><td><span class="math">I_{ev}</span></td><td>Current EV charger output current</td><td>Live reading</td></tr><tr><td><span class="math">I_{available}</span></td><td>Dynamically available current for EV charging</td><td>Calculated</td></tr></tbody></table>

**Core DLB formula:**

$$I\_{available} = I\_{max} - I\_{safe} - (I\_{grid} - I\_{ev})$$

> $$(I\_{grid} - I\_{ev})$$ represents the baseline load of all other household appliances.

***

### 3. Electrical Installation

> ⚠️ **Safety Notice:** Installation must be performed by qualified electricians only. Always de-energize the circuit before wiring.

#### 3.1 Typical Installation Position

The meter should be installed at the **main incomer** (grid entry point) of the consumer unit, **upstream of all loads including the EV charger**. This ensures $$I\_{grid}$$ reflects the true total household consumption.

#### 3.2 CT Orientation

The split-core CTs must be installed with the **correct polarity** (arrow pointing toward the load / away from the grid). Reversed CT orientation will result in negative power readings during normal import, which will break the DLB logic.

* **Positive value** = importing from grid (normal consumption)
* **Negative value** = exporting to grid (e.g. solar surplus)

#### 3.3 Supported CT Ratings

<table><thead><tr><th width="354">CT Rated Current</th><th>CT Aperture</th></tr></thead><tbody><tr><td>50 A</td><td>Ø10 mm</td></tr><tr><td>120 A</td><td>Ø16 mm</td></tr><tr><td>300 A</td><td>Ø24 mm</td></tr><tr><td>400 A</td><td>Ø36 mm</td></tr></tbody></table>

***

### 4. Network Configuration & Device Discovery

#### 4.1 Wi-Fi Provisioning (BLE)

The meter connects to your **2.4 GHz Wi-Fi** network. Provisioning is done via BLE. Two paths are available:

**Path A — BT Powerlink App (End-user / Installer)**

1. Download the **BT Powerlink** app.
2. **Scan the QR code** on the meter OR scan for nearby meters via BLE → select the target device.
3. Enter your router's SSID and password → push to the meter.
4. The meter connects to Wi-Fi and obtains an IP address via DHCP.

**Path B — Integrate BLE Provisioning into Your Own App (OEM)**

If you are building your own EV charger companion app and want to provision the meter directly from within it, use Bituo's BLE API:

> 💡 For SDM01 G2X and Combo Gen2, always use the **BLE Secured API**. The BLE Basic API is for Gen1 only and is NRND (Not Recommended for New Designs).

> 💡 **Best Practice:** After provisioning, configure a **DHCP static IP reservation** on the router (bound to the meter's MAC address) to prevent IP changes after router reboots.

#### 4.2 Automatic Device Discovery (mDNS)

* **Service type:** `_http._tcp.local`
* **Hostname format:** `energysensor-{model}-{mac}.local`
* **Example:** `energysensor-SDM01-c8b0d137f7c4.local`

Resolving this hostname always returns the meter's current IP, even after a DHCP lease renewal.

**Fallback — HTTP probe:**

```
GET http://<ip>/model
GET http://<ip>/sn/
```

A valid JSON response confirms the device is an SDM01 meter.

***

### 5. Communication Protocol Reference

#### 🎯 Protocol Selection Matrix

| Protocol       | Direction              | Recommended Interval            | Best For                                               | Encryption Option              |
| -------------- | ---------------------- | ------------------------------- | ------------------------------------------------------ | ------------------------------ |
| **Raw UDP**    | Meter → Charger (Push) | **0.5–1 s**                     | High-freq DLB, lowest latency                          | UDP AES                        |
| **HTTP**       | Charger → Meter (Poll) | **3–5 s**                       | Mid/low-freq DLB, config writes                        | HTTPS (Pro only)               |
| **Modbus TCP** | Charger → Meter (Poll) | **3–5 s**                       | Existing Modbus stack; single-charger only ⚠️          | Modbus TCP over TLS (Pro only) |
| **MQTT**       | Meter → Broker (Push)  | **1–5 s**                       | Multi-charger with Linux master / HEMS controller      | MQTTS                          |
| **WebSocket**  | Bidirectional          | **Continuous real-time stream** | Persistent real-time telemetry & bidirectional control | WSS (Pro only)                 |

> ⚠️ **TLS Concurrency Limit (Pro firmware):** The Gen2 Pro firmware supports a **maximum of 2 concurrent TLS connections recommended**, selecting from: Modbus TCP over TLS, HTTPS, MQTTS, and WSS. Plan your security architecture accordingly.

> ❌ **Never use HTTPS for high-frequency polling (such as < 3 s interval).** Every HTTPS request triggers a full TLS handshake on the ESP32-C6 SoC, saturating the CPU and causing watchdog resets. HTTPS is only acceptable for low-frequency queries or one-shot configuration writes.

> 💡 **WebSocket vs WSS:** Plain WebSocket (`ws://`) is sufficient for most LAN DLB deployments. Use WSS (`wss://`) only when your security policy or compliance requirement (e.g. EN 18031) mandates encrypted transport. WSS counts as 1 TLS connection toward the Gen2 Pro 2-connection limit.

***

#### 5.1 Raw UDP — Primary Protocol for High-Frequency DLB

**Best for:** Any DLB scenario requiring ≤ 1 s data freshness. The simplest and most efficient integration path.

| Parameter            | Value                                                       |
| -------------------- | ----------------------------------------------------------- |
| Transport            | **UDP (connectionless)**                                    |
| Target IPs           | Up to **5 unicast targets** configured via BT Powerlink app |
| Direction            | Meter **pushes** JSON to each configured target IP:Port     |
| Recommended interval | **0.5–1 second** (configurable, min \~0.5 s)                |
| Encryption           | Cleartext (default) / **UDP AES** (enable via app)          |

> 📌 **How UDP targeting works:** The meter performs **5 independent unicast sends** per interval — one to each configured target. There is no broadcast or multicast. Each target is an individual `IP:Port` pair configured in the BT Powerlink app (or via HTTP API). This means a maximum of **5 simultaneous receivers** (e.g. charger A, charger B, HEMS gateway, monitoring system) can receive data directly from one meter. For more than 5 receivers, use a Leader-Follower or HEMS gateway architecture (see Annex A).

> 📌 **Multicast support:** Multicast UDP delivery is planned for a future firmware release, which will remove the 5-target limit for LAN broadcast scenarios.

**5.1.1 Full Payload Example**

```json
{
  "Post": 142,
  "Time": 1785567041,
  "IP": "192.168.50.166",
  "Rssi": -46,
  "FWVersion": "3.1.7",
  "SerialNumber": "C8B0D137F7C4",
  "ProductModel": "SDM01_3PN",
  "MCUVersion": "001.01.00",
  "TP": 8,
  "VoltageX": "225.0",
  "VoltageY": "224.8",
  "VoltageZ": "224.8",
  "CurrentX": "0.000",
  "CurrentY": "0.000",
  "CurrentZ": "0.000",
  "ActivePowerX": "0.000",
  "ActivePowerY": "0.000",
  "ActivePowerZ": "0.000",
  "ReactivePowerX": "0.000",
  "ReactivePowerY": "0.000",
  "ReactivePowerZ": "0.000",
  "ApparentPowerX": "0.000",
  "ApparentPowerY": "0.000",
  "ApparentPowerZ": "0.000",
  "PowerFactorX": "1.00",
  "PowerFactorY": "1.00",
  "PowerFactorZ": "1.00",
  "UnbalanceLineCurrents": "0",
  "OverallPowerFactor": "1.00",
  "Frequency": "50.03",
  "ForwardEnergyX": "0.33",
  "ForwardEnergyY": "0.14",
  "ForwardEnergyZ": "0.47",
  "ReverseEnergyX": "0.00",
  "ReverseEnergyY": "0.00",
  "ReverseEnergyZ": "0.00"
}
```

**5.1.2 Field Reference**

The JSON payload is self-explanatory. Fields fall into two categories:

**Device & Session Fields** — metadata about the device and this packet: `Post` (sequence counter, increments by 1 each push — use to detect missed packets), `Time` (Unix timestamp), `IP` (meter's current LAN IP), `Rssi` (Wi-Fi signal strength in dBm), `FWVersion` / `MCUVersion` (firmware versions), `SerialNumber` (MAC-based unique device ID), `ProductModel` (e.g. `SDM01_3PN` = 3-phase 4-wire), `TP` (reporting interval in seconds).

**Electrical Measurement Fields** — per-phase readings for Voltage, Current, Active/Reactive/Apparent Power, Power Factor, and Energy. Phase suffix: `X` = L1, `Y` = L2, `Z` = L3.

> ⭐ **For DLB, the only fields you need are `CurrentX`, `CurrentY`, and `CurrentZ` (unit: Amperes).** Everything else is optional telemetry.

> ⚠️ **All measurement values are strings** (quoted numbers). Always parse with `float()` before arithmetic.

**5.1.3 Derived Values for DLB**

```python
I_X = float(payload["CurrentX"])
I_Y = float(payload["CurrentY"])
I_Z = float(payload["CurrentZ"])

# Option A: Worst-phase current — RECOMMENDED default
# Protects the most loaded single-phase breaker from tripping
I_grid = max(I_X, I_Y, I_Z)

# Option B: Sum of all phases — for 3-phase symmetric load budgeting
I_grid_total = I_X + I_Y + I_Z

```

> **Recommendation:** Use **Option A** (`max`) as the default DLB strategy. It is the most conservative and protects against single-phase breaker trips in unbalanced households.

**5.1.4 Sign Convention**

* **Positive** current / active power = **importing** from grid (normal consumption)
* **Negative** current / active power = **exporting** to grid (e.g. solar surplus)

**5.1.5 UDP AES (Encrypted Variant)**

Enable via BT Powerlink app. Payload structure and field names are **identical** to cleartext UDP; only the transport layer is AES-encrypted. The encryption key is the **broadcast key** derived during BLE secure pairing, shared between the meter and the paired app.&#x20;

***

#### 5.2 Modbus TCP — Mid-Frequency Polling for Single-Charger Deployments

**Best for:** Charger platforms with an existing Modbus TCP stack, at **3–5 s polling intervals**.

> ⚠️ **Critical: Single-Connection Limitation** The firmware supports **only ONE concurrent TCP connection** and actively resets the socket after each read request. You must:
>
> * Open a new TCP connection before each read
> * Close it immediately after
> * Wait a minimum of **150 ms** between consecutive reads
>
> **Practical implication for DLB:** Modbus TCP is suitable for **single-charger + single-meter** deployments only. If any other device on the same LAN attempts to poll the meter simultaneously (e.g. a monitoring tool, HEMS gateway, or another charger), the meter will reject the concurrent connection — which may disrupt your charger's DLB data acquisition. For multi-client or multi-charger scenarios, use Raw UDP or MQTT instead.

| Parameter             | Value                                            |
| --------------------- | ------------------------------------------------ |
| Port                  | **502** (TCP)                                    |
| Role                  | EV Charger = **Master**; Meter = **Slave**       |
| Slave ID              | `1` (default)                                    |
| Byte Order            | Big-Endian (**AB CD**)                           |
| Recommended poll rate | **3–5 s** (stable); 1–2 s (acceptable with care) |
| Function Codes        | `0x03`, `0x04` (read); `0x06` (write/control)    |

**Register Map — Key DLB Registers (Float32, AB CD)**

<table><thead><tr><th width="150">Address (Dec)</th><th width="147">Address (Hex)</th><th>Description</th><th>Unit</th></tr></thead><tbody><tr><td>1006</td><td><code>0x03EE</code></td><td>Current Phase A (L1)</td><td>A</td></tr><tr><td>1008</td><td><code>0x03F0</code></td><td>Current Phase B (L2)</td><td>A</td></tr><tr><td>1010</td><td><code>0x03F2</code></td><td>Current Phase C (L3)</td><td>A</td></tr><tr><td>1012</td><td><code>0x03F4</code></td><td>Active Power Phase A</td><td>kW</td></tr><tr><td>1014</td><td><code>0x03F6</code></td><td>Active Power Phase B</td><td>kW</td></tr><tr><td>1016</td><td><code>0x03F8</code></td><td>Active Power Phase C</td><td>kW</td></tr><tr><td>1044</td><td><code>0x0414</code></td><td>Total Active Power</td><td>kW</td></tr></tbody></table>

> 💡 **Modbus TCP over TLS** is available on Gen2 Pro firmware. Note the 2-connection TLS concurrency limit.

***

#### 5.3 MQTT — Multi-Charger / HEMS Local Controller Scenarios

**Best for:** Multi-charger deployments where a **Linux-based master charger** or a dedicated **HEMS Local Controller** (e.g. Home Assistant, OpenHAB, custom Linux gateway) can run a local MQTT broker.

> 📌 **Hardware prerequisite:** Running a local MQTT broker (e.g. Mosquitto, \~5 MB RAM) requires a Linux-capable host. This is **not suitable** for resource-constrained embedded MCUs (FreeRTOS / bare-metal). If your charger MCU cannot run a broker, use Raw UDP (up to 5 unicast targets) or the Leader-Follower architecture instead (see Annex A).

| Parameter             | Value                                                   |
| --------------------- | ------------------------------------------------------- |
| Port                  | **1883** (MQTT) / **8883** (MQTTS)                      |
| Direction             | Meter **publishes** to broker; charger(s) **subscribe** |
| Configurable interval | **1–30 s** (default: 5 s; adjustable to 1 s)            |
| QoS                   | 0 (telemetry `/data`), 0/1 (commands `/cmd`)            |

**Topic Architecture**

| Topic                | Direction      | Description                                   |
| -------------------- | -------------- | --------------------------------------------- |
| `{Model}/{SN}/data`  | Meter → Broker | Periodic telemetry (energy data)              |
| `{Model}/{SN}/cmd`   | Broker → Meter | Commands to meter                             |
| `{Model}/{SN}/cdata` | Meter → Broker | Command execution responses                   |
| `{Model}/{SN}/mdata` | Meter → Broker | Device metadata (published on boot, retained) |

**Example topics for SDM01\_3PN, SN C8B0D137F7C4:**

```
SDM01_3PN/C8B0D137F7C4/data
SDM01_3PN/C8B0D137F7C4/cmd
```

**MQTT Payload**

The MQTT `/data` payload is **structurally identical** to the UDP payload, with two additions:

* `TotalActivePower` — pre-calculated sum of all three phases (kW) ✅
* `TotalForwardEnergy` — pre-calculated total imported energy (kWh) ✅

These pre-calculated totals make MQTT slightly more convenient for DLB than UDP (no need to sum phases manually).

> 💡 **MQTTS:** Supported on all firmware branches. Counts as 1 TLS connection toward the Gen2 Pro 2-connection limit.

***

#### 5.4 HTTP — Mid/Low-Frequency Polling & Primary Configuration Channel

**Best for:** 3–5 s interval DLB polling (when UDP is not implemented), one-shot configuration writes, and diagnostic queries.

| Parameter             | Value                                     |
| --------------------- | ----------------------------------------- |
| Port                  | **80** (HTTP) / **443** (HTTPS, Pro only) |
| Recommended poll rate | **3–5 s** for DLB; ≤ once/min for HTTPS   |
| Response format       | **Identical JSON to UDP payload**         |

> 📌 **HTTP is the primary local configuration channel.** All device settings (UDP target IPs, MQTT broker address, reporting intervals, etc.) are written via HTTP POST. MQTT and BLE API are alternative configuration channels — see TL;DR.

> ⚠️ **Do NOT use HTTPS for DLB polling intervals < 3 s.** Each HTTPS request requires a full TLS handshake. At 1 s intervals this will saturate the ESP32-C6 CPU. HTTPS is acceptable for ≥ 3 s intervals or one-shot config writes only.

**Key endpoints:**

```
GET  http://<ip>/data          → Returns full JSON payload (same as UDP)
GET  http://<ip>/model         → Returns device model string
GET  http://<ip>/sn/           → Returns serial number
POST http://<ip>/config        → Write configuration parameters
```

***

#### 5.5 WebSocket — Persistent Real-Time Connection

**Best for:** Scenarios requiring a persistent connection for continuous real-time data streaming and bidirectional control (e.g. Home Assistant local integration, custom dashboards).

| Parameter                   | Value                    |
| --------------------------- | ------------------------ |
| Plain WebSocket (`ws://`)   | Port **81**              |
| Secure WebSocket (`wss://`) | Port **502** (or custom) |

> 💡 **Use plain WebSocket (`ws://`) by default.** WebSocket keeps the connection open, so the meter can push data continuously at full rate — equivalent to UDP in terms of data freshness, but with a persistent TCP channel. Only upgrade to WSS when your security policy or compliance requirement (e.g. EN 18031) explicitly mandates encrypted transport.

> 💡 WSS establishes a **persistent connection** — the TLS handshake happens only once at connection setup, then data flows with negligible overhead. This is why WSS is preferred over HTTPS for encrypted real-time data when TLS is required.

> ⚠️ WSS counts as 1 TLS connection toward the Gen2 Pro 2-connection limit.

For the complete JSON message format and command reference, see the **WebSocket API Protocol** documentation.

***

### 6. DLB Control Logic Implementation

#### 6.1 Threshold Configuration

| Parameter         | How to Set                                   | Example |
| ----------------- | -------------------------------------------- | ------- |
| $$I\_{max}$$      | User sets main breaker rating in charger app | 60 A    |
| $$I\_{safe}$$     | Fixed at 10–20% of $$I\_{max}$$              | 6 A     |
| Fallback current  | User configures (min 6 A per IEC 61851)      | 6 A     |
| Timeout threshold | 5–15 s (configurable)                        | 10 s    |

#### 6.2 Control Loop (Pseudocode)

```python
# DLB Control Loop — runs every 1 second (UDP) or every poll interval (HTTP/Modbus)
def dlb_loop():
    data = receive_meter_data()   # UDP packet, HTTP response, or Modbus read

    I_X = float(data["CurrentX"])
    I_Y = float(data["CurrentY"])
    I_Z = float(data["CurrentZ"])
    I_grid = max(I_X, I_Y, I_Z)  # Worst-phase strategy (recommended default)

    I_available = I_max - I_safe - (I_grid - I_ev)

    if I_grid > (I_max - I_safe):
        # RAMP DOWN — must complete within 2 seconds (safety-critical)
        I_ev_new = max(MIN_CURRENT, I_ev - STEP_DOWN)
        set_pwm_current(I_ev_new)

    elif I_available > I_ev + STEP_UP_THRESHOLD:
        # RAMP UP — slow and gradual to prevent oscillation
        if time_since_last_increase >= RAMP_UP_INTERVAL:
            I_ev_new = min(I_ev + 1, I_available)
            set_pwm_current(I_ev_new)

    if I_available < MIN_CURRENT:   # MIN_CURRENT = 6A per IEC 61851-1
        suspend_charging()
        wait_for_headroom()
```

> 📌 **Control parameters** (STEP\_DOWN, STEP\_UP\_THRESHOLD, RAMP\_UP\_INTERVAL, etc.) are charger-side design decisions. The values above are illustrative only. Charger manufacturers should tune these based on their own product requirements, grid conditions, and EV compatibility testing.

#### 6.3 Control Strategy Summary

| Condition                            | Action                                     | Speed                           |
| ------------------------------------ | ------------------------------------------ | ------------------------------- |
| $$I\_{grid} > I\_{max} - I\_{safe}$$ | Ramp **down** PWM immediately              | **Fast: within 2 s**            |
| $$I\_{available}$$ has surplus       | Ramp **up** PWM gradually (+1A steps)      | **Slow: configurable interval** |
| $$I\_{available} < 6A$$              | **Suspend** charging (IEC 61851-1 minimum) | Immediate                       |
| Data timeout                         | Trigger **Fallback** (see Section 6.4)     | Within timeout window           |

> **Why asymmetric speed?** Fast ramp-down prevents breaker trips (safety-critical). Slow ramp-up prevents control oscillation and avoids triggering the EV's BMS protection. Specific ramp rates and intervals are charger-side design decisions.

#### 6.4 Fail-Safe / Fallback Mechanism

> ⚠️ **This section is critical.** A DLB system that silently continues full-power charging when meter comms are lost is worse than no DLB at all.

**Trigger:** No meter data received for **10 consecutive seconds** (configurable, recommended range: 5–15 s).

**Fallback actions (in order):**

1. Immediately force charging current to minimum safe value (6 A).
2. If user enabled "Stop on comms loss": open relay and suspend charging.
3. Activate fault indicator + push notification: *"DLB communication lost"*.

**Recovery:** After **3 consecutive successful data reads/packets**, automatically exit Fallback and resume dynamic regulation.

***

### 7. Custom Firmware Path (Advanced)

> For EV charger manufacturers who prefer to run **proprietary firmware** on the meter's Wi-Fi SoC instead of using Bituo's stock firmware.

#### 7.1 Why Custom Firmware?

* Full control over Wi-Fi stack, security policies, and OTA update mechanism
* Deep integration with your own cloud platform or MQTT broker
* Compliance with your own cybersecurity certification requirements
* Eliminate dependency on Bituo's firmware release cycle

#### 7.2 Hardware Architecture

```
┌─────────────────────────────────────────────────────┐
│             SDM01 G2X / Combo Gen2                  │
│                                                     │
│  ┌──────────────────┐      ┌─────────────────────┐  │
│  │  Wi-Fi/BLE SoC   │      │   Base Meter MCU    │  │
│  │   (ESP32-C6)     │◄────►│  (Metering + RS485) │  │
│  │                  │ UART │                     │  │
│  │  YOUR FIRMWARE   │      │  Calibration data   │  │
│  │  runs here       │      │  stored here        │  │
│  └──────────────────┘      └─────────────────────┘  │
│         │                           │               │
│      Wi-Fi                       RS485              │
└─────────────────────────────────────────────────────┘
```

**Key principle:** Flashing custom firmware on the ESP32-C6 **does not affect metering accuracy or calibration data**, which are stored independently in the Base Meter MCU.

#### 7.3 Internal Data Interface: Modbus over UART

The ESP32-C6 reads energy data from the Base Meter MCU via **Modbus RTU over UART** (internal bus, separate from the external RS485 port).

> **Gen2 register compatibility:** The internal UART Modbus register map is **identical to Gen1 (ESP8685)**. Refer to the [SDM01 Combo (ESP8685) Custom Firmware Guide](https://docs.bituo-technik.com/custom-firmware/sdm01-combo-esp8685) for the complete register address table and UART parameters.

> 🛑 **DANGER: LETHAL VOLTAGE.** Always disconnect from AC mains before connecting any UART adapter.&#x20;

***

### 8. Testing & Validation Checklist

> 📌 **Note:** The following checklist covers the key integration touchpoints between the SDM01 meter and the EV charger. It is intended as a **starting reference only** — each charger manufacturer will have their own validation methodology, reliability testing standards, and certification requirements that go well beyond the scope of this guide.

#### 8.1 Communication Stability

* [ ] Open a UDP socket listener; verify packets arrive at the configured interval; verify `Post` counter increments by 1 each packet
* [ ] Simulate router power cycle → verify charger re-discovers meter via mDNS within 60 s
* [ ] Simulate Wi-Fi disconnection → verify Fallback triggers within configured timeout
* [ ] **(Modbus TCP only)** Verify no second client is simultaneously polling the meter; test connection reset behavior
* [ ] **Anti-pattern test:** Poll via HTTPS at 1 Hz → verify SoC reboots (confirms why UDP/HTTP is necessary for high-frequency use)

#### 8.2 DLB Response Latency

* [ ] Connect a 3 kW resistive load suddenly to the household circuit
* [ ] Capture charger CP signal (PWM) with oscilloscope
* [ ] **Pass criterion:** PWM duty cycle reduces within **< 2 seconds** of load connection

#### 8.3 Boundary Conditions

* [ ] Test $$I\_{available}$$ oscillating around 6 A → verify no rapid suspend/resume toggling
* [ ] Test Fallback trigger → verify charger drops to 6 A within timeout
* [ ] Test Fallback recovery → verify charger exits Fallback after 3 successful reads
* [ ] Test $$I\_{available}$$ < 6 A → verify charger suspends (does not attempt sub-minimum current)

#### 8.4 Custom Firmware (if applicable)

* [ ] Verify internal UART Modbus reads match RS485 external port readings
* [ ] Verify custom OTA mechanism works independently of Bituo firmware updates

***

### 9. FAQ

| Question                                                                                                | Answer                                                                                                                                                                                                                                       |
| ------------------------------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| **The meter's IP changed after a router reboot.**                                                       | Use mDNS: resolve `energysensor-SDM01-{mac}.local`. Or set a DHCP static IP reservation.                                                                                                                                                     |
| **Can I use HTTPS to poll every second?**                                                               | **No.** TLS handshakes will overheat the ESP32-C6 and cause reboots. Use Raw UDP for ≤ 1 s, or HTTP for 3–5 s intervals.                                                                                                                     |
| **What is the minimum charging current?**                                                               | 6 A per IEC 61851-1. If $$I\_{available}$$ < 6 A, suspend charging — do not attempt sub-minimum current.                                                                                                                                     |
| **How many chargers can receive UDP data simultaneously?**                                              | Up to **5** (5 independent unicast targets; multicast support is planned for a future firmware release). For > 5 chargers, use MQTT or Leader-Follower architecture.                                                                         |
| **If my charger is already using Modbus TCP, can another device also poll the meter at the same time?** | **Not recommended.** The meter supports only 1 concurrent Modbus TCP connection. Any second client will be rejected and may intermittently disrupt your charger's data acquisition. For multi-client scenarios, use Raw UDP or MQTT instead. |
| **Can I integrate BLE provisioning into my own app?**                                                   | Yes. Use the [BLE Secured API](https://docs.bituo-technik.com/device-api/spm-sdm-open-wi-fi-api-overview/ble-secured-api) for Gen2.                                                                                                          |
| **Does flashing custom firmware affect metering accuracy?**                                             | No. Calibration data is in the Base Meter MCU, unaffected by SoC firmware changes.                                                                                                                                                           |
| **What happens if the meter loses Wi-Fi during charging?**                                              | Charger detects data timeout (default 10 s) → Fallback: reduces to 6 A or suspends.                                                                                                                                                          |
| **How many TLS connections can Gen2 Pro handle simultaneously?**                                        | **Maximum 2 recommended**, selecting from: Modbus TCP over TLS, HTTPS, MQTTS, WSS. Plan your security architecture accordingly.                                                                                                              |

***

### Annex A — Multi-Charger DLB Architecture

#### A.1 Multi-Charger DLB Coordination — Architecture Comparison

> The two architectures below are both industry-validated and commonly seen in the field. **The "broadcast self-calculate" pattern — where each charger independently derives its own allocation from raw** $$I\_{grid}$$ **broadcast data — is generally not recommended**, as it requires real-time state synchronization between chargers and tends to be fragile when charger count changes or packets are dropped.

***

**🥇 Architecture A: Centralized Arbiter — Common for Residential & Small-Site**

Suitable for deployments where a single local controller coordinates all chargers. The **Arbiter** role can be fulfilled by:

* A designated charger (e.g., the first-installed or highest-rated unit), or
* A **local HEMS controller** or home energy gateway that already manages other loads (PV, battery, etc.)
* **Topology:** One entity acts as the **Arbiter**; all chargers it manages are **Followers**.
* **How it works:**
  * a. The Arbiter communicates with the smart meter (e.g., via UDP unicast), receiving $$I\_{grid}$$ data.
  * b. The Arbiter runs its allocation logic and determines an **individual current limit for each Follower**.
  * c. Each Follower's limit is delivered via LAN (e.g., UDP unicast, local MQTT, or a proprietary protocol).
* **SDM01 fit:** ✅ Up to 5 UDP unicast targets supported. The Arbiter (charger or HEMS controller) can receive meter push directly.
* **Typical advantages:**
  * Supports unequal power distribution and priority-based allocation
  * Fast trip-prevention response
  * Can leverage an existing HEMS controller without additional hardware

> ⚠️ **Note:** Each Follower should receive its **own dedicated current limit**, not the raw $$I\_{grid}$$ value. Allocation logic runs on the Arbiter side.

***

**🥈 Architecture B: OCPP Cloud Coordination — Common for Commercial Sites**

Suitable for commercial deployments or where multi-brand interoperability is required.

* **Topology:** All chargers connect to a cloud-based Charging Station Management System (CSMS) via OCPP 1.6J / 2.0.1.
* **How it works:**
  * a. The CSMS issues individual power/current limit schedules to each charger via `SetChargingProfile` (Smart Charging Profile).
  * b. Meter data is forwarded to the CSMS via MQTT/HTTP (directly or through a local HEMS gateway), allowing the CSMS to adjust profiles dynamically.
* **SDM01 fit:** ✅ Meter can publish data to a cloud CSMS via MQTT or HTTP, or via a local HEMS gateway.
* **Typical advantages:**
  * Open industry standard; cross-brand compatible
  * Supports advanced features: billing, scheduling, remote management
  * Scales well to larger sites

***

#### A.2 Architecture Comparison Summary

|                        | **Architecture A: Centralized Arbiter**    | **Architecture B: OCPP Cloud** |
| ---------------------- | ------------------------------------------ | ------------------------------ |
| **Arbiter**            | Charger or local HEMS controller           | Cloud CSMS                     |
| **Meter → Arbiter**    | UDP unicast (LAN)                          | MQTT / HTTP (cloud)            |
| **Arbiter → Chargers** | UDP unicast × N / local MQTT / proprietary | OCPP `SetChargingProfile`      |
| **SDM01 fit**          | ✅ Native                                   | ✅ Via MQTT / HTTP              |
| **Works offline**      | ✅ Yes                                      | ❌ No (cloud dependency)        |
| **Cross-brand**        | ❌ Typically same-ecosystem                 | ✅ OCPP standard                |
| **Best for**           | Residential / small site                   | Commercial / large site        |

***

#### A.3 Multi-Charger Current Distribution

This section outlines a **common approach** to current allocation in Architecture A. Charger manufacturers will typically implement their own allocation logic based on their product requirements — the following is provided as a reference pattern only.

**A.3.1 Available Current Calculation**

A typical starting point for the Arbiter's allocation calculation:

$$I\_{available} = I\_{max} - I\_{grid} + I\_{ev\_total}$$

Where:

* $$I\_{max}$$ — main breaker rated current
* $$I\_{grid}$$ — current grid import reading from the meter (e.g., worst phase)
* $$I\_{ev\_total}$$ — sum of current limits currently assigned to all active chargers (to avoid double-counting EV load already reflected in $$I\_{grid}$$)

**A.3.2 Common Allocation Strategies**

| Strategy                     | Description                                                     | Typical Use Case                           |
| ---------------------------- | --------------------------------------------------------------- | ------------------------------------------ |
| **Equal Share**              | $$I\_{available}$$ divided equally among all active sessions    | Simple same-charger deployments            |
| **Priority-Based**           | Higher-priority chargers receive allocation first               | VIP parking, fleet with SLA                |
| **Rated-Power Proportional** | Allocation proportional to each charger's rated maximum current | Mixed charger types (e.g., 7.4 kW + 22 kW) |

**A.3.3 Minimum Current Consideration (IEC 61851)**

Per IEC 61851-1, the minimum signalled current is **6 A**. Charger implementations typically handle the case where a calculated allocation falls below this threshold by suspending that session (signalling State B) and redistributing the quota — but the specific handling is left to the charger manufacturer's discretion.

**A.3.4 Ramp Behaviour Considerations**

* **Ramp-down** is typically applied quickly to all chargers when $$I\_{grid}$$ approaches the limit.
* **Ramp-up** is often staggered across chargers to reduce simultaneous inrush current risk.

The specific ramp rates and step sizes are implementation-defined by the charger manufacturer.

***

#### A.4 Multi-Level Fail-Safe Considerations

Single-charger fail-safe (§6) covers meter communication loss. In multi-charger deployments, additional failure scenarios are worth considering during system design.

**A.4.1 Common Failure Scenarios**

| Scenario                      | Typical Handling                                                                              |
| ----------------------------- | --------------------------------------------------------------------------------------------- |
| **Meter → Arbiter link lost** | Arbiter falls back to a conservative current limit for all chargers until meter comms recover |
| **Arbiter unavailable**       | Followers fall back to a safe local current limit (e.g., 6 A) after a timeout                 |
| **Follower goes offline**     | Arbiter may release that Follower's quota back to the pool for redistribution                 |
| **Meter + Arbiter both lost** | Followers suspend or reduce to minimum current independently                                  |

> 💡 The specific timeout values, fallback currents, and recovery sequences are implementation decisions for the charger manufacturer. The key principle is that **each layer should have an independent fallback** so that a single point of failure does not result in an uncontrolled overcurrent condition.

**A.4.2 Arbiter Recovery — General Considerations**

When the Arbiter recovers from a fault, it is generally advisable to:

1. Verify meter data is stable before resuming full allocation.
2. Re-query Follower states before recalculating limits.
3. Restore charging current gradually rather than all at once, to avoid simultaneous inrush from multiple EVs.


# SDM01 G2X & Combo Gen2 — Balcony Solar & Micro-Storage Export Limiting Integration Guide

{% hint style="info" %}
**Status:** Active| **Applies to:** SDM01 G2X and SDM01 Combo Gen2 | **Firmware:** Pro V3.1.11+  | **Audience:** Balcony Solar PV & Micro-Storage Product Managers and Firmware Engineers | **Last Updated:** 2026-08-11
{% endhint %}

#### TL;DR — Quick Decision Card

```
Recommended communication channel for export limiting
└── Raw UDP push  ← Primary channel
    Push-based, no connection overhead, configurable interval 0.2–0.5 s
    See Section 5.1

Fallback channel
└── Modbus TCP polling
    Use if your inverter/storage MCU already has a Modbus stack
    ⚠️ Single TCP connection; open → read → close per cycle, ≥ 150 ms gap
    See Section 5.2

Configuration and diagnostics (not for real-time control)
├── HTTP GET         ← Read current power data
├── HTTP POST        ← Write configuration (UDP target IP, etc.)
└── BLE              ← Local provisioning via BT Powerlink app or custom app

Security compliance required (EN 18031 / RED)?
└── UDP AES (encrypted push, same low latency as Raw UDP)
    Pre-shared key is shared with BLE broadcast key
    See Section 5.3

Want to build your own communication stack?
└── Contact Bituo for custom firmware support on ESP32-C6
    See Section 9

Typical end-to-end system response: 2–5 seconds
(varies by country, DNO, and inverter/storage design — see Section 3.2)
```

***

#### 1. Purpose & Scope

This guide helps balcony solar and micro-storage **product managers** and **firmware/embedded engineers** integrate the [**SDM01 Gen2 Combo**](/product-document/sdm-series/sdm01-combo-gen2) or [**SDM01 G2X**](/product-document/sdm-series/sdm01-g2x) smart energy meter into a system over a local Wi-Fi/LAN network to implement **Export Limiting** — also known as zero feed-in control or anti-backflow.

**What Export Limiting does:** By continuously monitoring the total grid power ($$P\_{grid}$$) at the home's main incomer, the balcony inverter or micro-storage unit dynamically adjusts its output so that net power exported to the grid stays within the regulatory limit (e.g. 0 W zero-feed-in, or within the 800 W cap under the 2024 German Balkonkraftwerk regulation).

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FovHJ6mJNOhkEZDZMEbTD%2FExport-Limiting-with-SDM01G2.png?alt=media&amp;token=db5e6c13-5264-45cb-a555-2956ee83233e" alt=""><figcaption></figcaption></figure>

> 📌 **Bituo Technik's role in this system:** The SDM01 Gen2 Combo / SDM01 G2X is the **real-time electrical monitoring and communication node** — it measures $$P\_{grid}$$ and delivers that data to your inverter or storage controller over Wi-Fi. The closed-loop control logic lives in your device. This guide focuses on getting accurate, low-latency power data from the meter to your system reliably.
>
> **The integration approach, control algorithm, fail-safe behavior, and grid-code compliance described in this guide are provided as reference examples only.** Export limiting control, output ramping, and regulatory compliance are implemented and validated by the inverter or storage system manufacturer.

**What this guide covers:**

* Supported products and selection guide
* System architecture and control flow
* Typical system-level response time
* Electrical installation and CT wiring
* Wi-Fi provisioning and device discovery
* Communication protocols (Raw UDP, Modbus TCP, HTTP, UDP AES)
* Export limiting control logic reference example
* Fail-safe and reconnection design
* Testing and validation checklist
* Custom firmware / open integration options

**Out of scope:** RS-485 / Modbus RTU integration — use the [SDM01 Modbus RTU Map](/device-api/sdm01-modbus-rtu-map) for that use case.

***

#### 2. Supported Products

Both products below support this export limiting integration over Wi-Fi. Select based on your installation environment.

<table data-header-hidden><thead><tr><th width="161"></th><th></th><th></th></tr></thead><tbody><tr><td></td><td> <a href="/product-document/sdm-series/sdm01-combo-gen2"><strong>SDM01 Gen2 Combo</strong></a> </td><td> <a href="/product-document/sdm-series/sdm01-g2x"><strong>SDM01 G2X</strong></a></td></tr><tr><td><strong>Measurement Update Rate</strong></td><td>≤ 200ms (Power RMS value)</td><td>≤ 200ms  (Power RMS value)</td></tr><tr><td><strong>Wi-Fi SoC</strong></td><td>ESP32-C6</td><td>ESP32-C6</td></tr><tr><td><strong>Antenna</strong></td><td>Built-in PCB antenna</td><td>External (SMA connector, antenna routable outside enclosure)</td></tr><tr><td><strong>Best fit</strong></td><td>Adequate Wi-Fi signal</td><td>Metal cabinets and weak Wi-Fi environments where adding WiFi AP is not feasible </td></tr></tbody></table>

> 💡 **Architecture note:** Both products use a dual-chip architecture — a dedicated **metering MCU** handles all energy measurement to ensure accuracy and isolation, while a separate **ESP32-C6 Wi-Fi SoC** manages connectivity and protocol handling. The two chips communicate internally via `UART`. Developers familiar with the ESP32 ecosystem can leverage this open interface for custom firmware or proprietary communication stacks.

***

#### 3. System Architecture Overview

**3.1 Control Flow**

<table><thead><tr><th width="170">Step</th><th width="259">Actor</th><th>Action</th></tr></thead><tbody><tr><td><strong>① Provision</strong></td><td>User / Installer</td><td>Configure meter Wi-Fi via BLE (BT Powerlink app or custom app via BLE API)</td></tr><tr><td><strong>② Discover</strong></td><td>Inverter / Storage MCU</td><td>Auto-discover meter IP on LAN via mDNS, or use DHCP-reserved static IP</td></tr><tr><td><strong>③ Communicate</strong></td><td>Inverter / Storage MCU</td><td>Receive UDP pushes from meter (or poll via Modbus TCP)</td></tr><tr><td><strong>④ Control</strong></td><td>Inverter / Storage MCU</td><td>Run export limiting control algorithm, adjust PV/storage output</td></tr><tr><td><strong>⑤ Fail-Safe</strong></td><td>Inverter / Storage MCU</td><td>On comms timeout, ramp output down to safe level</td></tr></tbody></table>

> 💡 **Configuring the UDP target address:** The meter needs to know which IP:Port to push UDP data to. This can be configured via any of the following channels:
>
> * **LAN HTTP** — `POST http://<meter-ip>/save-config` with `{"cmd":"udp","IpAddress":"<inverter-ip>","localUdpPort":<port>}` from the inverter MCU or any LAN client
> * **BLE** — via BT Powerlink app or your own app using the BLE Secured API (local, no internet required)
> * **Cloud MQTT** — via your app → cloud MQTT broker → meter (requires meter to be online)

**3.2 Typical System-Level Response Time**

The total time from a change in grid power to the inverter completing its output adjustment depends on multiple stages across the system. A typical well-designed system can achieve **2–5 seconds** end-to-end.

> ⚠️ The applicable response time requirement varies by country, region, DNO, and grid connection type. Always verify with the local grid code and connection agreement for your target market. The figures below are reference budgets only.

<table><thead><tr><th>Stage</th><th width="171">Reference Budget</th><th>Notes</th></tr></thead><tbody><tr><td><strong>① Metering IC — valid power value</strong></td><td>≤ 200 ms</td><td>The metering IC produces a valid, stable active power reading within 200 ms after a load change. This is the fundamental measurement latency floor.</td></tr><tr><td><strong>② MCU reads metering IC + Wi-Fi SoC transmits over network</strong></td><td>+ 50–100 ms</td><td>The MCU reads data from the metering IC, packages it, and the Wi-Fi SoC transmits the UDP packet over the LAN. Typical LAN UDP delivery adds 5–50 ms.</td></tr><tr><td><strong>③ Inverter / storage MCU receive &#x26; process</strong></td><td>10–100 ms</td><td>Parsing UDP packet, running control algorithm, issuing new power setpoint. Implemented by customer.</td></tr><tr><td><strong>④ Power electronics ramp / settling</strong></td><td>100–1000 ms</td><td>The inverter or storage unit physically ramps output to the new setpoint. Dominant factor; fully determined by inverter/storage design.</td></tr><tr><td><strong>End-to-end system response</strong></td><td><strong>Typically 2–5 s</strong></td><td>Must be validated by the system manufacturer on the final product.</td></tr></tbody></table>

**UDP push interval recommendation:**

The meter's UDP push interval is configurable. **0.5 s is recommended** for most balcony PV applications, balancing control responsiveness with MCU and network load. For systems with fast power electronics (ramp time < 200 ms) and capable inverter MCUs, the interval can be reduced to **0.2 s** to improve control responsiveness.

> 💡 Since the metering IC produces a valid power reading within \~200 ms, a 0.2 s push interval ensures every UDP packet carries a freshly computed measurement. At 0.5 s, each packet is still well within one measurement cycle. Both settings are appropriate depending on your system design.

**3.3 Key Parameters and Sign Convention**

<table><thead><tr><th width="141">Symbol</th><th>Description</th></tr></thead><tbody><tr><td><span class="math">P_{grid}</span></td><td>Real-time total grid power at main incomer. Unit: <strong>kW</strong> in UDP/HTTP. Multiply by 1000 for W.</td></tr><tr><td><span class="math">P_{export,max}</span></td><td>Maximum allowed export power, defined as a positive number (e.g. 0 W or 800 W)</td></tr><tr><td><span class="math">P_{margin}</span></td><td>Optional safety margin (e.g. 30–50 W)</td></tr><tr><td><span class="math">P_{target}</span></td><td>Controller target: <span class="math">-P_{export,max} + P_{margin}</span></td></tr><tr><td><span class="math">\Delta P</span></td><td>Control dead band (e.g. ±30–±50 W)</td></tr><tr><td><span class="math">T_{timeout}</span></td><td>Comms timeout before fail-safe triggers (configurable, e.g. 2–5 s)</td></tr></tbody></table>

**Sign convention (applies to all active power fields):**

| Value             | Meaning                                                            |
| ----------------- | ------------------------------------------------------------------ |
| $$P\_{grid} > 0$$ | Household is importing power from the grid                         |
| $$P\_{grid} = 0$$ | Net-zero grid exchange                                             |
| $$P\_{grid} < 0$$ | Household is exporting power to the grid → trigger export limiting |

***

#### 4. Electrical Installation

> ⚠️ **Safety Notice:** Installation must be performed by a qualified electrician. Always de-energize the circuit before wiring.

**4.1 Installation Position**

The meter must be installed at the **main incomer** (grid entry point) of the consumer unit, **upstream of all loads including the balcony inverter connection point**. This ensures $$P\_{grid}$$ reflects the true net household power balance.

```
Grid Supply
    │
┌───┴────────────────────────────────────────┐
│  Main Incomer                              │
│  [SDM01 Gen2 Combo / G2X — CT on all phases]  │  ← Install here
└───┬────────────────────────────────────────┘
    │
    ├── Household loads (appliances, lighting…)
    │
    └── Balcony inverter / micro-storage connection point
            (e.g. Schuko socket or dedicated circuit)
```

**4.2 CT Orientation and Phase Matching**

* The **arrow on the CT** must point toward the load (away from the grid supply).
* CT(L1) must be clamped on the **L1 phase conductor**, CT(L2) on L2, CT(L3) on L3.
* Mismatch between voltage measurement phase and CT phase will cause **incorrect power sign** and completely defeat export limiting logic.

> ⚠️ **Most common field issue:** Reversed CT orientation. If $$P\_{grid}$$ reads negative when the household is clearly importing (PV off), reverse the affected CT.

**4.3 Wiring Check — Verify Before Going Live**

After installation, use the BT Powerlink app or `HTTP GET /data` to verify:

1. All phase voltages read \~230 V (for 3P4W systems).
2. $$P\_{grid}$$ (`TotalActivePower`) is **positive** when household is consuming with no PV active.
3. Per-phase power signs are consistent — no phase reads opposite sign to the others under balanced load.
4. **Phase power factor check:** With PV off and normal household loads running, each phase power factor (`PowerFactorX/Y/Z`) should read between **0.7 and 1.0**. A reading outside this range or a negative power factor on one phase while others are normal typically indicates a CT orientation or phase matching error.

***

#### 5. Network Provisioning and Device Discovery

**5.1 Wi-Fi Provisioning via BLE**

Use the **BT Powerlink app** (Android / iOS) to provision the meter onto the same 2.4 GHz Wi-Fi network as the balcony inverter or storage unit:

1. Open BT Powerlink app → tap **Add Device**.
2. App scans for nearby meter via BLE.
3. Enter your Wi-Fi SSID and password → confirm.
4. Meter connects; ACT LED changes to slow blink (connected).

> 💡 **2.4 GHz only.** The meter connects to 2.4 GHz Wi-Fi only. If your router broadcasts a combined 2.4/5 GHz SSID, ensure the meter associates to the 2.4 GHz band, or use a dedicated 2.4 GHz SSID.

**5.2 Fixed IP — Recommended Primary Discovery**

Assign a DHCP reservation in the router for the meter's MAC address (find it in BT Powerlink app → **Device Info**). This gives the meter a stable IP across reboots and simplifies inverter-side configuration.

**5.3 mDNS Auto-Discovery — Recommended Fallback**

```
Service Type : _http._tcp.local.
Hostname     : energysensor-{model}-{mac}.local
Example      : energysensor-SDM01-c8b0d137f7c4.local
```

Integration pattern:

1. Browse for `_http._tcp.local.` on the LAN.
2. Filter for hostnames starting with `EnergySensor-SDM01`.
3. Resolve to IP and proceed with UDP or Modbus TCP.

> ⚠️ Some consumer routers block mDNS multicast between Wi-Fi clients. If discovery fails, check that **multicast/IGMP snooping** is enabled, or fall back to local network scan + HTTP probe.

**5.4 Local Network Scan + HTTP Probe — Last-Resort Discovery**

When fixed IP and mDNS both fail, scan the local network (e.g. via ARP scan or router client-list lookup) and probe each candidate:

```
GET http://<candidate-ip>/data
```

Response includes `model`, `mac`, and `firmware` fields. Match `ProductModel` against `SDM01_3PN` to confirm identity.

***

#### 6. Communication Protocols

**6.1 Raw UDP Push — Primary Channel ✅ Recommended**

Push-based, no connection overhead. The meter actively pushes data to a configured target IP:Port at a configurable interval.

**Configure UDP target (via BT Powerlink app or HTTP POST):**

```
POST http://<meter-ip>/save-config
{
  "cmd": "udp",
  "IpAddress": "<inverter-ip>",
  "localUdpPort": <port>
}
```

Or configure via BLE using the BLE Secured API, or via Cloud MQTT.

**Recommended push interval:** 0.5 s for most applications; 0.2 s for fast-response systems.

**Actual UDP message payload** (example from a live device):

```
{
  "Post": 20,
  "Time": 1786419136,
  "IP": "192.168.3.23",
  "Rssi": -41,
  "FWVersion": "3.1.12",
  "SerialNumber": "99B08567F7C1",
  "ProductModel": "SDM01_3PN",
  "MCUVersion": "001.01.00",
  "TP": 8,
  "VoltageX": "223.6",
  "VoltageY": "225.1",
  "VoltageZ": "223.3",
  "CurrentX": "8.711",
  "CurrentY": "8.117",
  "CurrentZ": "20.915",
  "ActivePowerX": "1.860",
  "ActivePowerY": "1.538",
  "ActivePowerZ": "4.518",
  "TotalActivePower": "7.916",
  "ReactivePowerX": "0.360",
  "ReactivePowerY": "-0.460",
  "ReactivePowerZ": "-0.315",
  "ApparentPowerX": "1.895",
  "ApparentPowerY": "1.605",
  "ApparentPowerZ": "4.529",
  "PowerFactorX": "0.98",
  "PowerFactorY": "0.96",
  "PowerFactorZ": "1.00",
  "UnbalanceLineCurrents": "66",
  "OverallPowerFactor": "1.00",
  "Frequency": "50.01",
  "ForwardEnergyX": "683.55",
  "ForwardEnergyY": "289.31",
  "ForwardEnergyZ": "1012.49",
  "TotalForwardEnergy": "1985.35",
  "ReverseEnergyX": "0.00",
  "ReverseEnergyY": "0.00",
  "ReverseEnergyZ": "0.00",
  "TotalReverseEnergy": "0.00"
}
```

> ⚠️ **Important implementation notes:**
>
> * All power and energy field values are **strings** — parse to float before use.
> * `TotalActivePower`, `ActivePowerX/Y/Z` unit is **kW**. Multiply by 1000 to get W.
> * Use `Time` field for freshness checking. Discard packets where `Time` is stale (> 10 s behind current time).
> * UDP is connectionless — implement a watchdog timer. If no packet is received for the configured timeout (e.g. 2–5 s), trigger fail-safe (see Section 8).

**6.2 Modbus TCP — Fallback Channel**

Use as a reliable fallback, or as primary if your MCU already has a Modbus stack.

```
Protocol  : Modbus TCP
Port      : 502
Slave ID  : 1
Byte Order: ABCD (big-endian, native mode)
```

> ⚠️ **Single-connection limit:** Firmware supports only one concurrent TCP connection. Open → read → close per cycle. Allow ≥ 150 ms between consecutive reads.

**Key registers for export limiting (Native Mode — ABCD byte order):**

<table><thead><tr><th width="143">Register (Dec)</th><th>Register (Hex)</th><th>Description</th><th width="145">Format</th><th>Notes</th></tr></thead><tbody><tr><td>1012</td><td>0x03F4</td><td>Active Power A</td><td>FLOAT32</td><td>Per-phase, signed. Use as control input for single-phase inverters — read the phase the inverter is connected to.</td></tr><tr><td>1014</td><td>0x03F6</td><td>Active Power B</td><td>FLOAT32</td><td>Per-phase, signed. Use as control input for single-phase inverters — read the phase the inverter is connected to.</td></tr><tr><td>1016</td><td>0x03F8</td><td>Active Power C</td><td>FLOAT32</td><td>Per-phase, signed. Use as control input for single-phase inverters — read the phase the inverter is connected to.</td></tr><tr><td><strong>1044</strong></td><td><strong>0x0414</strong></td><td><strong>Total Active Power</strong></td><td>FLOAT32</td><td>Primary control input for 3-phase inverters/storage systems.</td></tr></tbody></table>

Function codes `0x03` or `0x04` both supported. Recommended polling interval: **0.5–1 s**.

> 📌 For the full Modbus register map, see the SDM01 Documentation Center.

**6.3 HTTP GET /data — Diagnostics and Low-Frequency Reads**

HTTP is **not recommended as the primary real-time channel** for export limiting due to connection setup overhead. Use it for:

* Wiring verification during installation
* Low-frequency energy logging (> 5 s interval)
* Device discovery and health checks

**Request:**

```
GET http://<meter-ip>/data
```

**Example response** (from a live device at `192.168.3.23`):

```
{
  "Post": 92,
  "Time": 1786419230,
  "IP": "192.168.3.23",
  "Rssi": -37,
  "FWVersion": "3.1.12",
  "SerialNumber": "99B08567F7C1",
  "ProductModel": "SDM01_3PN",
  "VoltageX": "223.8",
  "VoltageY": "225.0",
  "VoltageZ": "223.1",
  "CurrentX": "8.735",
  "CurrentY": "8.077",
  "CurrentZ": "16.666",
  "ActivePowerX": "1.867",
  "ActivePowerY": "1.533",
  "ActivePowerZ": "3.564",
  "TotalActivePower": "6.964",
  "ReactivePowerX": "0.353",
  "ReactivePowerY": "-0.458",
  "ReactivePowerZ": "-0.452",
  "ApparentPowerX": "1.900",
  "ApparentPowerY": "1.600",
  "ApparentPowerZ": "3.593",
  "PowerFactorX": "0.98",
  "PowerFactorY": "0.96",
  "PowerFactorZ": "0.99",
  "UnbalanceLineCurrents": "49",
  "OverallPowerFactor": "1.00",
  "Frequency": "50.03",
  "ForwardEnergyX": "683.58",
  "ForwardEnergyY": "289.34",
  "ForwardEnergyZ": "1012.55",
  "TotalForwardEnergy": "1985.47",
  "ReverseEnergyX": "0.00",
  "ReverseEnergyY": "0.00",
  "ReverseEnergyZ": "0.00",
  "TotalReverseEnergy": "0.00"
}
```

The HTTP `/data` response uses the same field names and units as the UDP push payload.

**6.4 UDP AES — Encrypted Push**

For products requiring wireless security compliance (EN 18031, EU RED Directive), use **UDP AES encrypted push**:

* Same message structure and field names as Raw UDP
* Payload is AES-encrypted
* No latency penalty vs Raw UDP
* **The AES pre-shared key is the same key used for BLE electrical data broadcast encryption** — configure once via BT Powerlink app or BLE Secured API

***

#### 7. Export Limiting Control Logic (Reference Example)

> 📌 **This section is provided as a simplified reference example only.** The meter provides real-time grid power measurement; the actual closed-loop control algorithm, output ramping behavior, and grid-code compliance logic are implemented inside the inverter or storage controller. The approach described here is one common method — adapt it to your system's specific requirements.

**7.1 Power Sign Convention**

The control input field depends on your inverter topology:

<table><thead><tr><th width="276">Inverter Type</th><th width="254">Recommended Control Input</th><th>Field (UDP/HTTP)</th></tr></thead><tbody><tr><td><strong>3-phase inverter / 3-phase storage</strong></td><td>Total Active Power</td><td><code>TotalActivePower</code></td></tr><tr><td><strong>Single-phase micro-inverter (e.g. balcony PV)</strong></td><td>Active Power of the connected phase</td><td><code>ActivePowerX/Y/Z</code></td></tr><tr><td><strong>DNO requires per-phase zero export</strong></td><td>Monitor all 3 phases independently; trigger limiting when any phase goes negative</td><td>All three <code>ActivePowerX/Y/Z</code></td></tr></tbody></table>

> ⚠️ For single-phase micro-inverters: using `TotalActivePower` may mask per-phase export — e.g. the connected phase exports −500 W while the other two phases import +600 W total, making the sum appear positive. Always verify with your target DNO's metering and compliance requirements.

**7.2 Define the Export Limit Clearly**

To avoid sign mistakes, define the export limit as a positive number and derive the controller target:

<table><thead><tr><th width="178">Symbol</th><th>Description</th><th>Example</th></tr></thead><tbody><tr><td><span class="math">P_{export,max}</span></td><td>Maximum allowed export power, expressed as a positive number</td><td>0 W (zero-feed-in) or 800 W</td></tr><tr><td><span class="math">P_{margin}</span></td><td>Optional safety margin</td><td>30–50 W</td></tr><tr><td><span class="math">P_{target}</span></td><td>Target grid power for the controller</td><td><span class="math">-P_{export,max} + P_{margin}</span></td></tr></tbody></table>

**Note:** *The formula above applies when using `TotalActivePower` as the control input (3-phase inverter scenario). For single-phase control, substitute the per-phase power reading accordingly.*

**Examples:**

* **Zero-feed-in** ($$P\_{export,max}=0\text{ W}$$, $$P\_{margin}=30\text{ W}$$):$$P\_{target} = +30\text{ W}$$The system keeps a small import margin to avoid crossing zero.
* **800 W export cap** ($$P\_{export,max}=800\text{ W}$$, $$P\_{margin}=50\text{ W}$$):$$P\_{target} = -750\text{ W}$$The system allows export up to 750 W, keeping 50 W safety margin.

**7.3 Incremental PI Control Example**

**Error signal:**

$$e(t) = P\_{grid}(t) - P\_{target}$$

* $$e(t) > 0$$: grid power is above target (household importing) → control output **increases**
* $$e(t) < 0$$: grid power is below target (household exporting beyond limit) → control output **decreases**

**Incremental PI correction:**

$$\Delta P\_{out}(t) = K\_p \cdot e(t) + K\_i \cdot \int e(t),dt$$

**New output setpoint:**

$$P\_{out,new} = P\_{out,current} + \Delta P\_{out}$$

**Output clamping:**

$$P\_{out,new} = \text{clamp}(P\_{out,new},; 0\text{ W},; P\_{rated})$$

**7.4 Example Starting Parameters**

> These are starting points only. Tune according to your power electronics ramp rate, communication interval, and grid-code requirements.

| Parameter              | Example Value                     | Notes                                        |
| ---------------------- | --------------------------------- | -------------------------------------------- |
| $$K\_p$$               | 0.2–0.6                           | Reduce if oscillation is observed            |
| $$K\_i$$               | 0.1–0.3 s⁻¹                       | Too high may cause overshoot                 |
| Dead band $$\Delta P$$ | ±30–±50 W                         | Prevents micro-adjustments                   |
| UDP push interval      | 0.5 s (or 0.2 s for fast systems) | See Section 3.2                              |
| Control update trigger | On each valid new meter sample    | Do not reuse stale data as new measurements  |
| Output ramp limit      | Device-dependent                  | Implement inside inverter/storage controller |

**7.5 Dead Band**

```
if |P_grid - P_target| < ΔP:
    hold current output
else:
    update output setpoint
```

> For zero-feed-in systems, a small positive import margin (30–50 W) is usually more stable than targeting exactly 0 W.

**7.6 Anti-Windup**

When the output is clamped at 0 W or $$P\_{rated}$$, freeze the integral term to prevent accumulation:

```
if P_out_new is clamped:
    freeze or limit the integral term
else:
    update the integral term normally
```

This prevents slow recovery, overshoot, and oscillation after output saturation or communication recovery.

***

#### 8. Fail-Safe and Reconnection

> ⚠️ A robust fail-safe design is mandatory. Network instability must never result in uncontrolled grid export.

> 📌 **Note:** Communication timeout and export limiting response time are different concepts. Response time describes how quickly the system adjusts output under normal operation. Timeout describes when the controller should enter fail-safe after losing valid meter data. The timeout value should be selected by the system manufacturer based on safety strategy and grid-code requirements.

**8.1 Timeout Detection**

| Condition                                                          | Recommended Action                              |
| ------------------------------------------------------------------ | ----------------------------------------------- |
| No valid UDP packet received for configurable timeout (e.g. 2–5 s) | Ramp PV/storage output to configured safe level |
| Modbus TCP read fails for configurable consecutive cycles          | Ramp PV/storage output to configured safe level |
| Packet `Time` field is stale (> 10 s old)                          | Treat as timeout, increment timeout counter     |

**8.2 Last Valid Data Cache**

Cache the last valid $$P\_{grid}$$ reading. Use it to ride through transient single-packet losses rather than triggering full fail-safe immediately. Only trigger fail-safe on sustained loss beyond the configured timeout.

**8.3 Reconnection**

After fail-safe triggers:

1. Continue attempting UDP reception / Modbus TCP connection in the background.
2. Once valid data resumes, **gradually ramp** output back up — do not step directly to full power.
3. Example ramp rate: increase by no more than $$P\_{rated} / 10$$ per control cycle (e.g. per 0.5 s) until steady state.

***

#### 9. Testing and Validation Checklist

> 📌 The following checklist is provided as a reference only. The system integrator and inverter/storage manufacturer are responsible for defining and executing their own validation procedures.

* [ ] **Step 1 — Wiring:** CT orientation and phase matching correct. `TotalActivePower` positive when household is importing with PV off.
* [ ] **Step 2 — Power factor check:** With PV off and normal loads running, per-phase power factor reads 0.7–1.0. Abnormal readings indicate CT or phase wiring issues.
* [ ] **Step 3 — Provisioning:** Meter connected to Wi-Fi, ACT LED slow-blinks. IP confirmed via BT Powerlink app.
* [ ] **Step 4 — Discovery:** Inverter/storage MCU discovers meter via mDNS or fixed IP. UDP packets arriving at expected interval.
* [ ] **Step 5 — Export limiting ramp-up:** Gradually increase PV output. Observe `TotalActivePower` stabilizing near $$P\_{target}$$.
* [ ] **Step 6 — End-to-end response time:** Measure total time from step-change in load to inverter output settling. Validate against your target grid code requirement.
* [ ] **Step 7 — Fail-safe:** Disconnect meter from Wi-Fi. Confirm inverter/storage output ramps to safe level within the configured timeout.
* [ ] **Step 8 — Reconnection:** Restore Wi-Fi. Confirm system automatically resumes export limiting, output ramps up smoothly.

***

#### 10. Custom Firmware / Open Integration (SDM01 G2X & Combo Gen2)

The SDM01 G2X & Combo Gen2's communication module is based on an **ESP32-C6** SoC. For manufacturers requiring a proprietary communication stack or custom cloud integration, Bituo Technik can provide firmware customization support, flashing access, and metering interface documentation.

> 💡 **Important:** The ESP32-C6 handles **communication only**. Measurement accuracy is handled by a dedicated metering IC and is **not affected** by custom firmware on the ESP32-C6.

For custom firmware resources, flashing guides, and metering IC interface documentation, please contact <support@bituo-technik.com> or visit the [Documentation Center](https://docs.bituo-technik.com).

***


# Home Energy Management System Integration


# Home Assistant

### Zigbee 3.0

\
\
1）Z2M：清单\
2）ZHA：\
不建议使用在我们

### Open WiFi

1）使用Bituo PMD HACS插件连接\
2）直接连Mosquito MQTT服务器\
\
\
\
\
不推荐使用Tuya Integration从云端

### Tuya Zigbee

1\) Z2M

注意涂鸦的上报限制，参考BLog

\
\
/Tuya Zigbee\
\
\
Tuya WIFI\
1\) Tuya  Integration

不推荐使用Tuya Integration从云端


# SPM/SDM Zigbee Cluster Reference

This document details the device access standards, data models (Clusters/Attributes), and interaction commands for our Zigbee Smart Meter series (Single-Phase, Split-Phase, and Three-Phase).

{% hint style="info" %}
**Status:** Stable | **Applies to:** SPM/SDM Standard Zigbee 3.0 Version | **Firmware:** V10+ | **Updated:** 2026-04-25 | **What's New:** Re-organize the document to make it more readable
{% endhint %}

***

### 1. Device Overview

This profile applies to the following smart meter models. All devices communicate via the standard Zigbee 3.0 protocol with the default Endpoint set to `1`.

<details>

<summary><strong>Single-phase Type (SPM01-xxTZ-U01)</strong></summary>

<table><thead><tr><th width="64">#</th><th width="208">Ordering Number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SPM01-D2TZ-U01</td><td>SPM01 1PN FLEX/63A Standard Zigbee</td></tr><tr><td>2</td><td>SPM01-D1TZ-U01</td><td>SPM01 1PN MCBM-DM/63A Standard Zigbee</td></tr><tr><td>3</td><td>SPM01-U1TZ-U01</td><td>SPM01 1PN MCBM-UM/63A Standard Zigbee</td></tr></tbody></table>

</details>

<details>

<summary><strong>Split-phase Type (</strong>SDM02-TZ-*-U01<strong>)</strong></summary>

<table><thead><tr><th width="64">#</th><th width="208">Ordering Number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SDM02-TZ-12-U01</td><td>SDM02 Split-Phase SCTA-2×120A/Φ16 Standard Zigbee</td></tr><tr><td>2</td><td>SDM02-TZ-20-U01</td><td>SDM02 Split-Phase SCTA-2×200A/Φ20 Standard Zigbee</td></tr><tr><td>3</td><td>SDM02-TZ-10U-U01</td><td>SDM02 Split-Phase SCTA-2×100A/Φ12-UL2808 Standard Zigbee</td></tr></tbody></table>

</details>

<details>

<summary><strong>Three-phase Type (</strong>SPM02-xxTZ-U01; SDM01-TZM-*-U01<strong>)</strong></summary>

<table><thead><tr><th width="64">#</th><th width="208">Ordering Number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td>SPM02-D2TZ-U01</td><td>SPM02 3PN FLEX/63A Standard Zigbee</td></tr><tr><td>2</td><td>SPM02-D1TZ-U01</td><td>SPM02 3PN MCBM-DM/63A Standard Zigbee</td></tr><tr><td>3</td><td>SPM02-U1TZ-U01</td><td>SPM02 3PN MCBM-UM/63A Standard Zigbee</td></tr><tr><td>4</td><td>SDM01-TZM-12-U01</td><td>SDM01 SCTA-3×120A/Φ16 Zigbee (Std. ZB3.0) + RS485</td></tr><tr><td>5</td><td>SDM01-TZM-20-U01</td><td>SDM01 SCTA-3×200A/Φ20 Zigbee (Std. ZB3.0) + RS485</td></tr></tbody></table>

</details>

> 💡 **User Best Practices**
>
> 1. **Default Reporting Configuration**: For all reportable attributes, the default configuration is `Report Min Interval: 30s`, `Report Max Interval: 30s`, and `Report Changeable: 0`. This means the device is factory-defaulted to automatically report its data every 30 seconds.
> 2. **Multipliers & Divisors**: It is highly recommended to read all multiplier and divisor parameters **only once** upon device power-on/network joining. **Do not** configure reporting for these static parameters to avoid network congestion.
> 3. **Calculation Formula**: `Actual Value = Raw Value * Multiplier / Divisor`

***

### 2. Common Clusters

The following Clusters are **identical** across all Single-Phase, Two-Phase, and Three-Phase devices.

#### Basic (0x0000)

<table><thead><tr><th width="112">ID</th><th width="152">Attribute Name</th><th width="101">Data Type</th><th width="125">Access</th><th>Description</th></tr></thead><tbody><tr><td><code>0x0000</code></td><td>ZCLVersion</td><td>uint8</td><td>Read Only</td><td>ZCL Protocol Version</td></tr><tr><td><code>0x0001</code></td><td>ApplicationVersion</td><td>uint8</td><td>Read Only</td><td>Application Version</td></tr><tr><td><code>0x0002</code></td><td>StackVersion</td><td>uint8</td><td>Read Only</td><td>Stack Version</td></tr><tr><td><code>0x0003</code></td><td>HWVersion</td><td>uint8</td><td>Read Only</td><td>Hardware Version</td></tr><tr><td><code>0x0004</code></td><td>ManufacturerName</td><td>string</td><td>Read Only</td><td>Manufacturer Name</td></tr><tr><td><code>0x0005</code></td><td>ModelIdentifier</td><td>string</td><td>Read Only</td><td>Model Identifier</td></tr><tr><td><code>0x4000</code></td><td>SWBuildID</td><td>string</td><td>Read Only</td><td>Software Build ID</td></tr></tbody></table>

#### Identify (0x0003)

<table><thead><tr><th>ID / Cmd</th><th>Name</th><th width="127">Data Type</th><th width="138">Access</th><th>Description</th></tr></thead><tbody><tr><td><code>Attr 0x0000</code></td><td>IdentifyTime</td><td>uint16</td><td>Read &#x26; Write</td><td>Device Locating (Requires Firmware V10 or higher<br>)</td></tr><tr><td><code>Cmd 0x00</code></td><td>Identify</td><td>-</td><td>Command</td><td>Device LED blinks at 5Hz for 15s</td></tr><tr><td><code>Cmd 0x01</code></td><td>Identify Query</td><td>-</td><td>Command</td><td>Query Identify status</td></tr></tbody></table>

#### On/Off (0x0006)

> ⚠️ **Warning**: This Cluster does **NOT** control a physical relay. It is **ONLY** used for **Resetting Accumulated Energy** (clearing the total kWh data to zero). Default value is OFF. *(Requires Firmware V10+)*

| ID / Cmd      | Name  | Data Type | Access          | Description                           |
| ------------- | ----- | --------- | --------------- | ------------------------------------- |
| `Attr 0x0000` | OnOff | bool      | Read/Report/Set | Energy Reset Status                   |
| `Cmd 0x00`    | Off   | -         | Command         | No action                             |
| `Cmd 0x01`    | On    | -         | Command         | Execute Energy Reset (Clear kWh to 0) |

#### Diagnostics (0x0B05) & OTA (0x0019)

* **Diagnostics (0x0B05)**:
  * `Attr 0x011C` LastMessageLQI (Read Only)
  * `Attr 0x011D` LastMessageRSSI (Read Only)
* **OTA (0x0019)**: Supports standard Zigbee OTA upgrade processes.

***

### 3. Electrical Measurement (0x0B04)

This Cluster is used to read real-time electrical measurement data (Voltage, Current, Power, Frequency, etc.). Please select the tab corresponding to your device type:\ <br>

{% tabs %}
{% tab title="Single-Phase" %}

<table><thead><tr><th width="93">ID</th><th width="202">Attribute Name</th><th width="97">Data Type</th><th width="165">Access</th><th width="83">Unit</th><th width="202">Description</th></tr></thead><tbody><tr><td><code>0x0300</code></td><td>ACFrequency</td><td>uint16</td><td>Report &#x26; Read</td><td><strong>Hz</strong></td><td>AC Frequency</td></tr><tr><td><code>0x0400</code></td><td>ACFrequencyMultiplier</td><td>uint16</td><td>Report &#x26; Read</td><td>-</td><td>AC Frequency Multiplier</td></tr><tr><td><code>0x0401</code></td><td>ACFrequencyDivisor</td><td>uint16</td><td>Report &#x26; Read</td><td>-</td><td>AC Frequency Divisor</td></tr><tr><td><code>0x0505</code></td><td>RMSVoltage</td><td>uint16</td><td>Report &#x26; Read</td><td><strong>V</strong></td><td>RMS Voltage (Phase A / Single Phase)</td></tr><tr><td><code>0x0508</code></td><td>RMSCurrent</td><td>uint16</td><td>Report &#x26; Read</td><td><strong>A</strong></td><td>RMS Current (Phase A / Single Phase)</td></tr><tr><td><code>0x050B</code></td><td>ActivePower</td><td>int16</td><td>Report &#x26; Read</td><td><strong>W</strong></td><td>Active Power (Phase A / Single Phase)</td></tr><tr><td><code>0x050F</code></td><td>ApparentPower</td><td>uint16</td><td>Report &#x26; Read</td><td><strong>VA</strong></td><td>Apparent Power (Phase A / Single Phase)</td></tr><tr><td><code>0x0510</code></td><td>PowerFactor</td><td>int8</td><td>Report &#x26; Read</td><td><strong>%</strong></td><td>Power Factor (Phase A / Single Phase)</td></tr><tr><td><code>0x0600</code></td><td>ACVoltageMultiplier</td><td>uint16</td><td>Report &#x26; Read</td><td>-</td><td>AC Voltage Multiplier</td></tr><tr><td><code>0x0601</code></td><td>ACVoltageDivisor</td><td>uint16</td><td>Report &#x26; Read</td><td>-</td><td>AC Voltage Divisor</td></tr><tr><td><code>0x0602</code></td><td>ACCurrentMultiplier</td><td>uint16</td><td>Report &#x26; Read</td><td>-</td><td>AC Current Multiplier</td></tr><tr><td><code>0x0603</code></td><td>ACCurrentDivisor</td><td>uint16</td><td>Report &#x26; Read</td><td>-</td><td>AC Current Divisor</td></tr><tr><td><code>0x0604</code></td><td>ACPowerMultiplier</td><td>uint16</td><td>Report &#x26; Read</td><td>-</td><td>AC Power Multiplier</td></tr><tr><td><code>0x0605</code></td><td>ACPowerDivisor</td><td>uint16</td><td>Report &#x26; Read</td><td>-</td><td>AC Power Divisor</td></tr></tbody></table>
{% endtab %}

{% tab title="Two-Phase/Split-Phase" %}

<table><thead><tr><th width="145">ID</th><th width="201">Attribute Name</th><th width="101">Data Type</th><th width="165">Access</th><th width="101">Unit</th><th width="197">Description</th></tr></thead><tbody><tr><td><strong>Global Measurements</strong></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td><code>0x0300</code></td><td>ACFrequency</td><td>uint16</td><td>Report &#x26; Read</td><td><strong>Hz</strong></td><td>AC Frequency</td></tr><tr><td><code>0x0304</code></td><td>TotalActivePower</td><td>int32</td><td>Report &#x26; Read</td><td><strong>W</strong></td><td>Total Active Power</td></tr><tr><td><code>0x0305</code></td><td>TotalReactivePower</td><td>int32</td><td>Report &#x26; Read</td><td><strong>VAr</strong></td><td>Total Reactive Power</td></tr><tr><td><code>0x0306</code></td><td>TotalApparentPower</td><td>uint32</td><td>Report &#x26; Read</td><td><strong>VA</strong></td><td>Total Apparent Power</td></tr><tr><td><code>0x0400</code></td><td>ACFrequencyMultiplier</td><td>uint16</td><td>Report &#x26; Read</td><td>-</td><td>AC Frequency Multiplier</td></tr><tr><td><code>0x0401</code></td><td>ACFrequencyDivisor</td><td>uint16</td><td>Report &#x26; Read</td><td>-</td><td>AC Frequency Divisor</td></tr><tr><td><strong>Phase A Measurements</strong></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td><code>0x0505</code></td><td>RMSVoltage</td><td>uint16</td><td>Report &#x26; Read</td><td><strong>V</strong></td><td>Phase A RMS Voltage</td></tr><tr><td><code>0x0508</code></td><td>RMSCurrent</td><td>uint16</td><td>Report &#x26; Read</td><td><strong>A</strong></td><td>Phase A RMS Current</td></tr><tr><td><code>0x050B</code></td><td>ActivePower</td><td>int16</td><td>Report &#x26; Read</td><td><strong>W</strong></td><td>Phase A Active Power</td></tr><tr><td><code>0x050E</code></td><td>ReactivePower</td><td>int16</td><td>Report &#x26; Read</td><td><strong>VAr</strong></td><td>Phase A Reactive Power</td></tr><tr><td><code>0x050F</code></td><td>ApparentPower</td><td>uint16</td><td>Report &#x26; Read</td><td><strong>VA</strong></td><td>Phase A Apparent Power</td></tr><tr><td><code>0x0510</code></td><td>PowerFactor</td><td>int8</td><td>Report &#x26; Read</td><td><strong>%</strong></td><td>Phase A Power Factor</td></tr><tr><td><strong>Global Multipliers &#x26; Divisors</strong></td><td></td><td></td><td></td><td></td><td><em>(Applies to all phases)</em></td></tr><tr><td><code>0x0600</code></td><td>ACVoltageMultiplier</td><td>uint16</td><td>Report &#x26; Read</td><td>-</td><td>AC Voltage Multiplier</td></tr><tr><td><code>0x0601</code></td><td>ACVoltageDivisor</td><td>uint16</td><td>Report &#x26; Read</td><td>-</td><td>AC Voltage Divisor</td></tr><tr><td><code>0x0602</code></td><td>ACCurrentMultiplier</td><td>uint16</td><td>Report &#x26; Read</td><td>-</td><td>AC Current Multiplier</td></tr><tr><td><code>0x0603</code></td><td>ACCurrentDivisor</td><td>uint16</td><td>Report &#x26; Read</td><td>-</td><td>AC Current Divisor</td></tr><tr><td><code>0x0604</code></td><td>ACPowerMultiplier</td><td>uint16</td><td>Report &#x26; Read</td><td>-</td><td>AC Power Multiplier</td></tr><tr><td><code>0x0605</code></td><td>ACPowerDivisor</td><td>uint16</td><td>Report &#x26; Read</td><td>-</td><td>AC Power Divisor</td></tr><tr><td><strong>Phase B Measurements</strong></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td><code>0x0905</code></td><td>RMSVoltage</td><td>uint16</td><td>Report &#x26; Read</td><td><strong>V</strong></td><td>Phase B RMS Voltage</td></tr><tr><td><code>0x0908</code></td><td>RMSCurrent</td><td>uint16</td><td>Report &#x26; Read</td><td><strong>A</strong></td><td>Phase B RMS Current</td></tr><tr><td><code>0x090B</code></td><td>ActivePower</td><td>int16</td><td>Report &#x26; Read</td><td><strong>W</strong></td><td>Phase B Active Power</td></tr><tr><td><code>0x090E</code></td><td>ReactivePower</td><td>int16</td><td>Report &#x26; Read</td><td><strong>VAr</strong></td><td>Phase B Reactive Power</td></tr><tr><td><code>0x090F</code></td><td>ApparentPower</td><td>uint16</td><td>Report &#x26; Read</td><td><strong>VA</strong></td><td>Phase B Apparent Power</td></tr><tr><td><code>0x0910</code></td><td>PowerFactor</td><td>int8</td><td>Report &#x26; Read</td><td><strong>%</strong></td><td>Phase B Power Factor</td></tr></tbody></table>

{% endtab %}

{% tab title="Three-Phase " %}

<table><thead><tr><th width="155">ID</th><th width="204">Attribute Name</th><th width="111">Data Type</th><th width="167">Access</th><th width="81">Unit</th><th width="221">Description</th></tr></thead><tbody><tr><td><strong>Global Measurements</strong></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td><code>0x0300</code></td><td>ACFrequency</td><td>uint16</td><td>Report &#x26; Read</td><td><strong>Hz</strong></td><td>AC Frequency</td></tr><tr><td><code>0x0304</code></td><td>TotalActivePower</td><td>int32</td><td>Report &#x26; Read</td><td><strong>W</strong></td><td>Total Active Power</td></tr><tr><td><code>0x0305</code></td><td>TotalReactivePower</td><td>int32</td><td>Report &#x26; Read</td><td><strong>VAr</strong></td><td>Total Reactive Power</td></tr><tr><td><code>0x0306</code></td><td>TotalApparentPower</td><td>uint32</td><td>Report &#x26; Read</td><td><strong>VA</strong></td><td>Total Apparent Power</td></tr><tr><td><code>0x0400</code></td><td>ACFrequencyMultiplier</td><td>uint16</td><td>Report &#x26; Read</td><td>-</td><td>AC Frequency Multiplier</td></tr><tr><td><code>0x0401</code></td><td>ACFrequencyDivisor</td><td>uint16</td><td>Report &#x26; Read</td><td>-</td><td>AC Frequency Divisor</td></tr><tr><td><strong>Phase A Measurements</strong></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td><code>0x0505</code></td><td>RMSVoltage</td><td>uint16</td><td>Report &#x26; Read</td><td><strong>V</strong></td><td>Phase A RMS Voltage</td></tr><tr><td><code>0x0508</code></td><td>RMSCurrent</td><td>uint16</td><td>Report &#x26; Read</td><td><strong>A</strong></td><td>Phase A RMS Current</td></tr><tr><td><code>0x050B</code></td><td>ActivePower</td><td>int16</td><td>Report &#x26; Read</td><td><strong>W</strong></td><td>Phase A Active Power</td></tr><tr><td><code>0x050E</code></td><td>ReactivePower</td><td>int16</td><td>Report &#x26; Read</td><td><strong>VAr</strong></td><td>Phase A Reactive Power</td></tr><tr><td><code>0x050F</code></td><td>ApparentPower</td><td>uint16</td><td>Report &#x26; Read</td><td><strong>VA</strong></td><td>Phase A Apparent Power</td></tr><tr><td><code>0x0510</code></td><td>PowerFactor</td><td>int8</td><td>Report &#x26; Read</td><td><strong>%</strong></td><td>Phase A Power Factor</td></tr><tr><td><strong>Global Multipliers &#x26; Divisors</strong></td><td></td><td></td><td></td><td></td><td><em>(Applies to all phases)</em></td></tr><tr><td><code>0x0600</code></td><td>ACVoltageMultiplier</td><td>uint16</td><td>Report &#x26; Read</td><td>-</td><td>AC Voltage Multiplier</td></tr><tr><td><code>0x0601</code></td><td>ACVoltageDivisor</td><td>uint16</td><td>Report &#x26; Read</td><td>-</td><td>AC Voltage Divisor</td></tr><tr><td><code>0x0602</code></td><td>ACCurrentMultiplier</td><td>uint16</td><td>Report &#x26; Read</td><td>-</td><td>AC Current Multiplier</td></tr><tr><td><code>0x0603</code></td><td>ACCurrentDivisor</td><td>uint16</td><td>Report &#x26; Read</td><td>-</td><td>AC Current Divisor</td></tr><tr><td><code>0x0604</code></td><td>ACPowerMultiplier</td><td>uint16</td><td>Report &#x26; Read</td><td>-</td><td>AC Power Multiplier</td></tr><tr><td><code>0x0605</code></td><td>ACPowerDivisor</td><td>uint16</td><td>Report &#x26; Read</td><td>-</td><td>AC Power Divisor</td></tr><tr><td><strong>Phase B Measurements</strong></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td><code>0x0905</code></td><td>RMSVoltage</td><td>uint16</td><td>Report &#x26; Read</td><td><strong>V</strong></td><td>Phase B RMS Voltage</td></tr><tr><td><code>0x0908</code></td><td>RMSCurrent</td><td>uint16</td><td>Report &#x26; Read</td><td><strong>A</strong></td><td>Phase B RMS Current</td></tr><tr><td><code>0x090B</code></td><td>ActivePower</td><td>int16</td><td>Report &#x26; Read</td><td><strong>W</strong></td><td>Phase B Active Power</td></tr><tr><td><code>0x090E</code></td><td>ReactivePower</td><td>int16</td><td>Report &#x26; Read</td><td><strong>VAr</strong></td><td>Phase B Reactive Power</td></tr><tr><td><code>0x090F</code></td><td>ApparentPower</td><td>uint16</td><td>Report &#x26; Read</td><td><strong>VA</strong></td><td>Phase B Apparent Power</td></tr><tr><td><code>0x0910</code></td><td>PowerFactor</td><td>int8</td><td>Report &#x26; Read</td><td><strong>%</strong></td><td>Phase B Power Factor</td></tr><tr><td><strong>Phase C Measurements</strong></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td><code>0x0A05</code></td><td>RMSVoltage</td><td>uint16</td><td>Report &#x26; Read</td><td><strong>V</strong></td><td>Phase C RMS Voltage</td></tr><tr><td><code>0x0A08</code></td><td>RMSCurrent</td><td>uint16</td><td>Report &#x26; Read</td><td><strong>A</strong></td><td>Phase C RMS Current</td></tr><tr><td><code>0x0A0B</code></td><td>ActivePower</td><td>int16</td><td>Report &#x26; Read</td><td><strong>W</strong></td><td>Phase C Active Power</td></tr><tr><td><code>0x0A0E</code></td><td>ReactivePower</td><td>int16</td><td>Report &#x26; Read</td><td><strong>VAr</strong></td><td>Phase C Reactive Power</td></tr><tr><td><code>0x0A0F</code></td><td>ApparentPower</td><td>uint16</td><td>Report &#x26; Read</td><td><strong>VA</strong></td><td>Phase C Apparent Power</td></tr><tr><td><code>0x0A10</code></td><td>PowerFactor</td><td>int8</td><td>Report &#x26; Read</td><td><strong>%</strong></td><td>Phase C Power Factor</td></tr></tbody></table>

{% endtab %}
{% endtabs %}

### 4. Metering (0x0702)

This Cluster is used to read the accumulated energy data (Delivered/Received energy).<br>

> 💡 **Implementation Note for Multi-Phase Energy** In the standard Zigbee ZCL specification, the `Tier 1/2/3` attributes are originally designed for Time-of-Use (TOU) pricing. To simplify gateway integration and keep all data unified on a single Endpoint (EP1), we have mapped these Tier attributes to represent the individual phase energy:
>
> * **Tier 1** maps to **Phase A**
> * **Tier 2** maps to **Phase B**
> * **Tier 3** maps to **Phase C**

{% tabs %}
{% tab title="Single-Phase" %}

<table><thead><tr><th width="98">ID</th><th width="247">Attribute Name</th><th width="104">Data Type</th><th width="161">Access</th><th width="107">Unit</th><th width="164">Description</th></tr></thead><tbody><tr><td><code>0x0000</code></td><td>CurrentSummationDelivered</td><td>uint48</td><td>Report &#x26; Read</td><td><strong>kWh</strong></td><td>Total forward energy</td></tr><tr><td><code>0x0001</code></td><td>CurrentSummationReceived</td><td>uint48</td><td>Report &#x26; Read</td><td><strong>kWh</strong></td><td>Total reverse energy</td></tr><tr><td><code>0x0301</code></td><td>Multiplier</td><td>uint24</td><td>Read Only</td><td>-</td><td>Energy Multiplier</td></tr><tr><td><code>0x0302</code></td><td>Divisor</td><td>uint24</td><td>Read Only</td><td>-</td><td>Energy Divisor</td></tr></tbody></table>
{% endtab %}

{% tab title="Two-Phase / Split-Phase" %}

<table><thead><tr><th width="116">ID</th><th width="285">Attribute Name</th><th width="115">Data Type</th><th width="175">Access</th><th width="73">Unit</th><th width="261">Description</th></tr></thead><tbody><tr><td><code>0x0000</code></td><td>CurrentSummationDelivered</td><td>uint48</td><td>Report &#x26; Read</td><td><strong>kWh</strong></td><td>Total forward energy</td></tr><tr><td><code>0x0001</code></td><td>CurrentSummationReceived</td><td>uint48</td><td>Report &#x26; Read</td><td><strong>kWh</strong></td><td>Total reverse energy</td></tr><tr><td><code>0x0100</code></td><td>CurrentTier1SummationDelivered</td><td>uint48</td><td>Report &#x26; Read</td><td><strong>kWh</strong></td><td>Phase A forward energy (Requires Firmware V11+)</td></tr><tr><td><code>0x0101</code></td><td>CurrentTier1SummationReceived</td><td>uint48</td><td>Report &#x26; Read</td><td><strong>kWh</strong></td><td>Phase A reverse energy (Requires Firmware V11+)</td></tr><tr><td><code>0x0102</code></td><td>CurrentTier2SummationDelivered</td><td>uint48</td><td>Report &#x26; Read</td><td><strong>kWh</strong></td><td>Phase B forward energy (Requires Firmware V11+)</td></tr><tr><td><code>0x0103</code></td><td>CurrentTier2SummationReceived</td><td>uint48</td><td>Report &#x26; Read</td><td><strong>kWh</strong></td><td>Phase B reverse energy (Requires Firmware V11+)</td></tr><tr><td><code>0x0301</code></td><td>Multiplier</td><td>uint24</td><td>Read Only</td><td>-</td><td>Energy Multiplier</td></tr><tr><td><code>0x0302</code></td><td>Divisor</td><td>uint24</td><td>Read Only</td><td>-</td><td>Energy Divisor</td></tr></tbody></table>
{% endtab %}

{% tab title="Three-Phase" %}

<table><thead><tr><th>ID</th><th width="284">Attribute Name</th><th>Data Type</th><th width="165">Access</th><th width="89">Unit</th><th width="192">Description</th></tr></thead><tbody><tr><td><code>0x0000</code></td><td>CurrentSummationDelivered</td><td>uint48</td><td>Report &#x26; Read</td><td><strong>kWh</strong></td><td>Total forward energy</td></tr><tr><td><code>0x0001</code></td><td>CurrentSummationReceived</td><td>uint48</td><td>Report &#x26; Read</td><td><strong>kWh</strong></td><td>Total reverse energy</td></tr><tr><td><code>0x0100</code></td><td>CurrentTier1SummationDelivered</td><td>uint48</td><td>Report &#x26; Read</td><td><strong>kWh</strong></td><td>Phase A forward energy (Requires Firmware V11+)</td></tr><tr><td><code>0x0101</code></td><td>CurrentTier1SummationReceived</td><td>uint48</td><td>Report &#x26; Read</td><td><strong>kWh</strong></td><td>Phase A reverse energy (Requires Firmware V11+)</td></tr><tr><td><code>0x0102</code></td><td>CurrentTier2SummationDelivered</td><td>uint48</td><td>Report &#x26; Read</td><td><strong>kWh</strong></td><td>Phase B forward energy (Requires Firmware V11+)</td></tr><tr><td><code>0x0103</code></td><td>CurrentTier2SummationReceived</td><td>uint48</td><td>Report &#x26; Read</td><td><strong>kWh</strong></td><td>Phase B reverse energy (Requires Firmware V11+)</td></tr><tr><td><code>0x0104</code></td><td>CurrentTier3SummationDelivered</td><td>uint48</td><td>Report &#x26; Read</td><td><strong>kWh</strong></td><td>Phase C forward energy (Requires Firmware V11+)</td></tr><tr><td><code>0x0105</code></td><td>CurrentTier3SummationReceived</td><td>uint48</td><td>Report &#x26; Read</td><td><strong>kWh</strong></td><td>Phase C reverse energy (Requires Firmware V11+)</td></tr><tr><td><code>0x0301</code></td><td>Multiplier</td><td>uint24</td><td>Read Only</td><td>-</td><td>Energy Multiplier</td></tr><tr><td><code>0x0302</code></td><td>Divisor</td><td>uint24</td><td>Read Only</td><td>-</td><td>Energy Divisor</td></tr></tbody></table>
{% endtab %}
{% endtabs %}

### 5. Custom Cluster

#### Modbus CFG (0xFC00)

This is our proprietary Custom Cluster, specifically designed for configuring devices with Modbus functionality.

> ⚠️ **Prerequisites & Requirements**
>
> * **Applicable Models**: Only **SDM01 Combo (3-phase version with Modbus)**.
> * **Version Requirement**: Requires Firmware V10+.
> * **Authentication**: Reading and writing to this Cluster requires the Manufacturer Code `0x1216` to be included in the Zigbee payload.

<table><thead><tr><th>ID</th><th>Attribute Name</th><th>Data Type</th><th>Access</th><th width="108">Default</th><th width="207">Description</th></tr></thead><tbody><tr><td><code>0x0000</code></td><td>SlaveID</td><td>uint8</td><td>Read &#x26; Write</td><td>247</td><td>Modbus Slave ID / Address</td></tr><tr><td><code>0x0001</code></td><td>BaudRate</td><td>enum8</td><td>Read &#x26; Write</td><td>19200</td><td>Communication Baud Rate</td></tr><tr><td><code>0x0002</code></td><td>ParityStop</td><td>enum8</td><td>Read &#x26; Write</td><td>N81</td><td>Parity &#x26; Stop Bit Configuration</td></tr></tbody></table>


# SDM01 Modbus RTU Map

{% hint style="info" %}
**Status:** Stable | **Applies to:** SDM01 Combo ALL | **Updated:** 2026-04-01&#x20;
{% endhint %}

### 1. Applied Product Models

<table><thead><tr><th width="64">#</th><th width="208">Ordering Number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td><strong>SDM01-TWM-12TS</strong></td><td>SCTA-3×120A/Φ16 Wi-Fi (Tuya LAN+) + RS485</td></tr><tr><td>2</td><td><strong>SDM01-TWM-20TS</strong></td><td>SCTA-3×200A/Φ20 Wi-Fi (Tuya LAN+) + RS485</td></tr><tr><td>3</td><td><strong>SDM01-TWM-12</strong></td><td>SCTA-3×120A/Φ16 Wi-Fi (Tuya) + RS485</td></tr><tr><td>4</td><td><strong>SDM01-TWM-20</strong></td><td>SCTA-3×200A/Φ20 Wi-Fi (Tuya) + RS485</td></tr><tr><td>5</td><td><strong>SDM01-TZM-12</strong></td><td>SCTA-3×120A/Φ16 Zigbee (Tuya) + RS485</td></tr><tr><td>6</td><td><strong>SDM01-TZM-20</strong></td><td>SCTA-3×200A/Φ20 Zigbee (Tuya) + RS485</td></tr><tr><td>7</td><td><strong>SDM01-EWM-12</strong></td><td>SDM01 SCTA-3×120A/Φ16 Wi-Fi (ESP32) + RS485</td></tr><tr><td>8</td><td><strong>SDM01-EWM-20</strong></td><td>SDM01 SCTA-3×200A/Φ20 Wi-Fi (ESP32) + RS485</td></tr><tr><td>9</td><td><strong>SDM01-TZM-12-U01</strong></td><td>SDM01 SCTA-3×120A/Φ16 Zigbee (Std. ZB3.0) + RS485</td></tr><tr><td>10</td><td><strong>SDM01-TZM-20-U01</strong></td><td>SDM01 SCTA-3×200A/Φ20 Zigbee (Std. ZB3.0) + RS485</td></tr></tbody></table>

***

### 2. Physical Layer & Wiring Guide

> **💡 Default Communication Parameters:** **Baud Rate:** 9600 bps | **Data Bits:** 8 | **Parity:** None | **Stop Bits:** 1 | **Default Address:** 247

* **Cable Type:** Twisted pair cable (Shielded highly recommended for industrial environments).
* **Topology:** Bus (Daisy-chain). *Strictly avoid Star or T-branch wiring.*
* **Cable Specification:** AWG 24-16.
* **Maximum Distance:** 800 - 1200m (at 9600 bps).
* **Termination Resistor:** 120Ω (Required at both physical endpoints of the bus).
* **Bus Capacity:** Max 32 nodes per segment (Up to 256 nodes if using 1/8 Unit Load drivers).

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FRmolZyDrDAJ24zh4U2AA%2Fimage.png?alt=media&amp;token=e920ab71-b99c-4c26-877f-844b9745d131" alt=""><figcaption></figcaption></figure>

***

### 3. Modbus Register Map

#### 📌 General Notes for Integrators

* **Function Codes Supported:** `0x03` (Read Holding), `0x04` (Read Input), `0x06` (Write Single), `0x10` (Write Multiple).
* **Endianness (Byte Order):** All `FLOAT32` data types follow **Big-Endian (ABCD)** byte order.
* **Register Offset:** All addresses listed below are **0-based** (Protocol Addresses). If your PLC/Master requires 1-based addressing (e.g., 40001 format), please add `40001` to the DEC address.

#### 3.1 Product Identification

<table><thead><tr><th width="105">Address (DEC)</th><th width="112">Address (HEX)</th><th width="197">Description</th><th>Func Code</th><th width="80">R/W</th><th width="98">Bytes</th><th>Data Type</th><th>Value / Range</th></tr></thead><tbody><tr><td>100</td><td><code>0x0064</code></td><td>Meter Type</td><td>03, 04</td><td>R</td><td>20</td><td>UTF8 String</td><td>"iMeter_3PN" (or Custom)</td></tr><tr><td>110</td><td><code>0x006E</code></td><td>Manufacturer</td><td>03, 04</td><td>R</td><td>20</td><td>UTF8 String</td><td>"The Manufacturer" (or Custom)</td></tr><tr><td>120</td><td><code>0x0078</code></td><td>Product ID</td><td>03, 04</td><td>R</td><td>10</td><td>UTF8 String</td><td>"SDM01x" (or Custom)</td></tr><tr><td>125</td><td><code>0x007D</code></td><td>Serial Number</td><td>03, 04, 10</td><td>R/W</td><td>10</td><td>UTF8 String</td><td>"YYWWZZZZ" (Digits only)</td></tr><tr><td>130</td><td><code>0x0082</code></td><td>Hardware Version</td><td>03, 04</td><td>R</td><td>10</td><td>UTF8 String</td><td>Format: "xxx.xx.xx"</td></tr><tr><td>135</td><td><code>0x0087</code></td><td>Firmware Version</td><td>03, 04</td><td>R</td><td>10</td><td>UTF8 String</td><td>Format: "xxx.xx.xx"</td></tr></tbody></table>

#### 3.2 Basic Metering Data

*Note: All Float32 values occupy 2 Modbus Registers (4 Bytes).*

<table><thead><tr><th width="110">Address (DEC)</th><th width="106">Address (HEX)</th><th width="231">Description</th><th>Func Code</th><th width="75">R/W</th><th>Data Type</th><th>Range</th><th>Unit</th></tr></thead><tbody><tr><td>1000</td><td><code>0x03E8</code></td><td>Voltage A-N</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 - 1000</td><td>V</td></tr><tr><td>1002</td><td><code>0x03EA</code></td><td>Voltage B-N</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 - 1000</td><td>V</td></tr><tr><td>1004</td><td><code>0x03EC</code></td><td>Voltage C-N</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 - 1000</td><td>V</td></tr><tr><td>1006</td><td><code>0x03EE</code></td><td>Current A</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 - 1000</td><td>A</td></tr><tr><td>1008</td><td><code>0x03F0</code></td><td>Current B</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 - 1000</td><td>A</td></tr><tr><td>1010</td><td><code>0x03F2</code></td><td>Current C</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 - 1000</td><td>A</td></tr><tr><td>1012</td><td><code>0x03F4</code></td><td>Active Power A</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1000 - 1000</td><td>kW</td></tr><tr><td>1014</td><td><code>0x03F6</code></td><td>Active Power B</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1000 - 1000</td><td>kW</td></tr><tr><td>1016</td><td><code>0x03F8</code></td><td>Active Power C</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1000 - 1000</td><td>kW</td></tr><tr><td>1018</td><td><code>0x03FA</code></td><td>Reactive Power A</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1000 - 1000</td><td>kVAR</td></tr><tr><td>1020</td><td><code>0x03FC</code></td><td>Reactive Power B</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1000 - 1000</td><td>kVAR</td></tr><tr><td>1022</td><td><code>0x03FE</code></td><td>Reactive Power C</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1000 - 1000</td><td>kVAR</td></tr><tr><td>1024</td><td><code>0x0400</code></td><td>Apparent Power A</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1000 - 1000</td><td>kVA</td></tr><tr><td>1026</td><td><code>0x0402</code></td><td>Apparent Power B</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1000 - 1000</td><td>kVA</td></tr><tr><td>1028</td><td><code>0x0404</code></td><td>Apparent Power C</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1000 - 1000</td><td>kVA</td></tr><tr><td>1030</td><td><code>0x0406</code></td><td>Power Factor A</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1.0 - 1.0</td><td>-</td></tr><tr><td>1032</td><td><code>0x0408</code></td><td>Power Factor B</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1.0 - 1.0</td><td>-</td></tr><tr><td>1034</td><td><code>0x040A</code></td><td>Power Factor C</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1.0 - 1.0</td><td>-</td></tr><tr><td>1036</td><td><code>0x040C</code></td><td>Average Voltage L-N</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 - 1000</td><td>V</td></tr><tr><td>1038</td><td><code>0x040E</code></td><td>Average Line Current</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 - 1000</td><td>A</td></tr><tr><td>1040</td><td><code>0x0410</code></td><td>Unbalanced Line Currents</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-300 - 300</td><td>%</td></tr><tr><td>1042</td><td><code>0x0412</code></td><td>Total Line Currents</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 - 3000</td><td>A</td></tr><tr><td>1044</td><td><code>0x0414</code></td><td>Total Active Power</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-3000 - 3000</td><td>kW</td></tr><tr><td>1046</td><td><code>0x0416</code></td><td>Total Reactive Power</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-3000 - 3000</td><td>kVAR</td></tr><tr><td>1048</td><td><code>0x0418</code></td><td>Total Apparent Power</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-3000 - 3000</td><td>kVA</td></tr><tr><td>1050</td><td><code>0x041A</code></td><td>Total Power Factor</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1.0 - 1.0</td><td>-</td></tr><tr><td>1052</td><td><code>0x041C</code></td><td>Frequency</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 - 1000</td><td>Hz</td></tr><tr><td>1054</td><td><code>0x041E</code></td><td>Total Import Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1056</td><td><code>0x0420</code></td><td>Total Export Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1058</td><td><code>0x0422</code></td><td>Total Import &#x26; Export Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1060</td><td><code>0x0424</code></td><td>Phase A Import Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1062</td><td><code>0x0426</code></td><td>Phase A Export Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1064</td><td><code>0x0428</code></td><td>Phase A Import &#x26; Export Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1066</td><td><code>0x042A</code></td><td>Phase B Import Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1068</td><td><code>0x042C</code></td><td>Phase B Export Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1070</td><td><code>0x042E</code></td><td>Phase B Import &#x26; Export Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1072</td><td><code>0x0430</code></td><td>Phase C Import Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1074</td><td><code>0x0432</code></td><td>Phase C Export Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1076</td><td><code>0x0434</code></td><td>Phase C Import &#x26; Export Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr></tbody></table>

#### 3.3 RS485 Communication Settings

<table><thead><tr><th width="102">Address (DEC)</th><th width="111">Address (HEX)</th><th width="161">Description</th><th>Func Code</th><th>R/W</th><th>Data Type</th><th>Value Mapping</th><th>Default</th></tr></thead><tbody><tr><td>6000</td><td><code>0x1770</code></td><td>Modbus Address</td><td>03, 04, 06, 10</td><td>R/W</td><td>UINT16</td><td><code>1 - 246</code> (Valid Node IDs)</td><td><code>247</code></td></tr><tr><td>6001</td><td><code>0x1771</code></td><td>Baud Rate</td><td>03, 04, 06, 10</td><td>R/W</td><td>UINT16</td><td><code>0</code> = 9600<br><code>1</code> = 2400<br><code>2</code> = 4800<br><code>3</code> = 9600<br><code>4</code> = 19200<br><code>5</code> = 38400</td><td><code>0</code> (9600 bps)</td></tr><tr><td>6002</td><td><code>0x1772</code></td><td>Parity / Stop Bits</td><td>03, 04, 06, 10</td><td>R/W</td><td>UINT16</td><td><code>0</code> = N, 8, 1<br><code>1</code> = E, 8, 1<br><code>2</code> = O, 8, 1<br><code>3</code> = N, 8, 2</td><td><code>0</code> (N, 8, 1)</td></tr></tbody></table>

***

### 4. Control & Broadcast Commands

#### 4.1 Device Specific Commands (Unicast)

Send these commands to a specific device's Modbus address.

| Address (DEC) | Address (HEX) | Description                            | Func Code | R/W | Data Type | Write Value      |
| ------------- | ------------- | -------------------------------------- | --------- | --- | --------- | ---------------- |
| 10000         | `0x2710`      | Trigger LED Blinking (Device Locating) | 06        | W   | UINT16    | `0x5055` (20565) |
| 10001         | `0x2711`      | Reset Energy Accumulators              | 06        | W   | UINT16    | `0x51AA` (20906) |

> 🔍 **Feature: Device Locating via LED** When multiple meters are installed in a dense electrical panel, send `0x5055` to a specific device's Slave ID. The target meter's **LED will blink rapidly for 15 seconds**, allowing field engineers to visually identify the physical device corresponding to that IP/Slave ID.

#### 4.2 Broadcast Address Assignment

Send this command to **Broadcast Address `0`**.

<table><thead><tr><th width="106.39996337890625">Address (DEC)</th><th width="104">Address (HEX)</th><th width="120.7999267578125">Description</th><th width="85.5999755859375">Func Code</th><th width="75.2000732421875">R/W</th><th width="124.7999267578125">Data Type</th><th>Write Value</th></tr></thead><tbody><tr><td>30000</td><td><code>0x7530</code></td><td>Assign Modbus Address (Button Triggered)</td><td>10</td><td>W</td><td>2× UINT16</td><td><code>0x55AA</code> + <code>[New Address]</code></td></tr></tbody></table>

> **🛠️ How to use Broadcast Address Assignment:** This feature allows quick commissioning without needing to wire devices one by one.
>
> 1. The Host PLC sends a broadcast write command (Slave ID = `0`) to register `30000`.
> 2. The payload must be 2 words (4 bytes): `0x55AA` followed by the `[New Address]` (e.g., `0x0005`).
> 3. **Action:** Only the meter that currently has its **physical reset button pressed** will accept this command and update its address. All other meters on the bus will ignore it.

***

### 5. Compatible Meter Emulation

To ensure seamless integration with existing Home Energy Management Systems (EMS) automation applications - such Dynamic Load Balancing and Export limiting, the SDM01 series features **automatic register mapping emulation** for the standard versions of industry-leading meters.

The compatibility depends on the specific SDM01 model series, as detailed in the table below:

| SDM01 Model Series                                                      | Compatible Emulation (Standard Versions)                   |
| ----------------------------------------------------------------------- | ---------------------------------------------------------- |
| <p><strong>SDM01-TWM-</strong>\* <br><strong>SDM01-TZM-</strong>\*</p>  | <p>• Eastron SDM630MCT<br>• ABB B23</p>                    |
| <p><strong>SDM01-EWM-</strong>*<br><strong>SDM01-TZM-*-U01</strong></p> | <p>• Eastron SDM630MCT<br>• ABB B23<br>• CHINT DTSU666</p> |

**Scope of Emulation:** This emulation covers all commonly used core electrical parameters. If your PLC, SCADA, or automation system already has a built-in driver or template for the meters above, you can connect the SDM01 and read data directly without modifying your Modbus polling profiles.

The seamlessly mapped parameters include:

* **Voltage (U) & Current (I)** (Per phase)
* **Power** (Per phase Active Power and Total Active Power)
* **Energy** (Per phase Forward Active Energy and the Total Value, Per phase Reserve Active Energy and the Total Value)

*(Note: Emulation focuses on standard metering data. Manufacturer-specific diagnostic or hardware configuration registers are not included. **Important:** In solar export limiting applications, brands like Eastron and CHINT frequently supply customized models to specific inverter manufacturers. These custom versions may have modified register maps that are incompatible with the standard common registers. If you are unsure about the compatibility of your specific meter version, please contact the document maintainer for confirmation.)*<br>


# SPM/SDM Open Wi-Fi API Overview

## Open Wi-Fi API Overview

{% hint style="info" %}
**Status:** Active | **Applies to:** SPM/SDM Open Wi-Fi Series (ESP32-8685 / C6) | **Updated:** 2026-07-12
{% endhint %}

### 1. Introduction

Our smart energy meters using ESP32 SoCs are designed with an "Open Wi-Fi" philosophy, providing developers and system integrators with a comprehensive suite of local and cloud-based communication protocols.

This section of the documentation is organized into **sub-pages** detailing specific protocols. Before diving into the specific API references in the left sidebar, please review the firmware compatibility matrix below to ensure your device supports the required features.

***

### 2. Firmware Branches & Hardware Compatibility

The Open Wi-Fi product line currently consists of four main firmware branches.

| Firmware Branch      | Basic (8685)                       | Basic+ (8685)                               | Lite (8685)                                 | Pro (C6)                           |
| -------------------- | ---------------------------------- | ------------------------------------------- | ------------------------------------------- | ---------------------------------- |
| **Target Hardware**  | SPM / SDM                          | SDM01                                       | SPM/SDM                                     | SDM01 Gen2                         |
| **Latest Version**   | B\_5.1.14 & B\_6.1.7 <sup>1)</sup> | BPlus\_1.2.8 & BPlus\_2.2.4 <sup>2)</sup>   | Lite\_5.1.11 & Lite\_6.1.4<sup>2)</sup>     | Pro\_V3.1.11                       |
| **Core Features**    | Cleartext BLE & Wi-Fi              | Cleartext BLE, Encrypted WiFi <sup>3)</sup> | Encrypted BLE & Cleartext WiFi<sup>3)</sup> | Encrypted BLE & WiFi <sup>3)</sup> |
| **WiFi Strength**    | 0 dB                               | 13 dB                                       | 0dB                                         | 13 dB                              |
| **Lifecycle Status** | NRND                               | NRND                                        | Active                                      | Active                             |

**Note:**

1. `B_6.1.7` is used for the SDM01 Combo with UART external flashing pin, while `B_5.1.14` is used for all other Open WiFi models of SPM01, SPM02, SDM01 Combo with JTAG external flashing pins, and SDM02.
2. `BPlus_2.2.4` and `Lite_5.1.11` are used for the SDM01 Combo with UART external flashing pin, while `BPlus_2.2.4` and `Lite_6.1.4` are used for the SDM01 Combo with JTAG external flashing pins.
3. **Basic+** was formerly known as the EV/PV version for Gen1, which is replaced by the SDM01 Gen2. It supports a maximum of 1 TLS connection over Wi-Fi (Select 1 out of Modbus TCP, HTTPS, MQTT, and WebSocket).
4. **Lite** version's BLE encryption covers both provisioning and data broadcasting. Its Wi-Fi only supports TLS 1.2 and 1.3 for MQTT, and no TLS over HTTP, Modbus TCP and Websocket are supported.
5. **Pro** version's BLE encryption covers both provisioning and data broadcasting. Its Wi-Fi supports up to 2 concurrent TLS connections (Select 2 out of Modbus TCP, HTTPS, MQTT, and WebSocket).

***

### 3. API Capability Matrix

The following matrix details the supported communication protocols across different firmware branches. **The primary evolution from Basic/Basic+/Lite to Pro focuses on enhanced security and concurrency.**

| Firmware Branch           | Basic&#xA;(8685, SPM/SDM) |  Basic+&#xA;(8685, SDM01)  |   Lite&#xA;（8685，SPM/SDM）  |  Pro &#xA;(C6, SDM01 Gen2) |
| ------------------------- | :-----------------------: | :------------------------: | :------------------------: | :------------------------: |
| **BLE Cleartext**         |             ✅             |              ✅             |              ❌             |              ❌             |
| **BLE Secured**           |             ❌             |              ❌             |              ✅             |              ✅             |
| **MQTT (Port 1883)**      |             ✅             |              ✅             |              ✅             |              ✅             |
| **MQTTS (TLS Encrypted)** |             ✅             |              ✅             |              ✅             |              ✅             |
| **HTTP (Cleartext)**      |  <p>✅<br>(Default ON)</p> | <p>✅<br>(Default OFF )</p> | <p>✅<br>(Default OFF )</p> | <p>✅<br>(Default OFF )</p> |
| **HTTPS**                 |             ❌             |              ❌             |              ❌             |              ✅             |
| **Modbus TCP**            |             ✅             |              ✅             |              ✅             |              ✅             |
| **Modbus TCP over TLS**   |             ❌             |              ✅             |              ❌             |              ✅             |
| **Websocket**             |             ✅             |              ✅             |              ✅             |              ✅             |
| **Websocket over TLS**    |             ❌             |              ✅             |              ❌             |              ✅             |
| **UDP**                   |             ✅             |              ✅             |              ✅             |              ✅             |
| **UDP AES**               |             ❌             |              ❌             |              ✅             |              ✅             |
| **mDNS Discovery**        |             ✅             |              ✅             |              ✅             |              ✅             |

{% hint style="warning" %}
**Important Note on TLS Resources:** Due to the memory constraints of embedded devices, concurrent TLS connections (MQTTS, HTTPS, Websocket over TLS, Modbus over TLS) are strictly limited.&#x20;

* For **Basic+** firmware, a maximum of **1 TLS connection** is recommended at a time.&#x20;
* For **Pro** firmware, a maximum of 2 **TLS connection** is recommended at a time.

Please design your integration to reuse existing connections.&#x20;
{% endhint %}

***

### 4. API Reference Directory

Explore the sub-pages in this section based on your integration architecture:

#### 🌐 Cloud & Backend Integration

* [**MQTT API Reference**](/device-api/spm-sdm-open-wi-fi-api-overview/mqtt-api-reference): The recommended protocol for continuous telemetry data streaming and cloud control. *(Includes complete JSON payload definitions for voltage, current, power, etc. Note: The `seq` field is deprecated in Basic 5.1.14+).*

#### 🏠 Local Smart Home & LAN Integration

* [**mDNS Discovery**](/device-api/spm-sdm-open-wi-fi-api-overview/mdns-discovery):  How to automatically discover Bituo meters on a local network without static IPs.
* **HTTP API Reference**: Standard RESTful endpoints (GET/POST) for local device configuration and on-demand data polling.
* **WebSocket API Reference** *(Coming Soon)*: Real-time, bi-directional communication for local hubs like Home Assistant.
* **UDP Broadcasting** *(Coming Soon)*: High-frequency, connectionless local data streaming for real-time energy monitoring and zero-export systems.

#### 🔋 Local EMS & Gateway Integration

* **Modbus TCP Map**: Standard Modbus register maps for local energy gateways, solar/EV systems, and software-based building management systems (BMS).

#### 📱 Mobile App & Proximity Control

* **BLE Cleartext API**: Bluetooth passthrough API for legacy Basic/Basic+ firmware.
* **BLE Secured API**: Encrypted PAKE Bluetooth API for Lite/Pro firmware, covering secure provisioning, local control, and encrypted energy data broadcasting.


# MQTT API Reference

## MQTT API Reference

{% hint style="info" %}
**Status:** Draft | **Applies to:** SPM/SDM Open WiFi (ESP32-8685)  | **Firmware:** Basic 5.1.14+ (SPM/SDM) / Basic 6.1.4+(SDM01 UART Flashing PIN) | **Updated:** 2026-06-23
{% endhint %}

### 1. Overview

The Bituo SPM/SDM series smart meters can communicate over MQTT using a **publish/subscribe** model. The device pushes telemetry data periodically and responds to JSON commands sent from the server.

**Important Notes for Firmware Basic 5.1.14+/6.1.4+:**

* Command architecture is unified with the BLE API.
* The `seq` (sequence) field is **deprecated** and no longer used in requests or responses.
* Command responses follow a standardized `ok/msg/event/d` structure.

***

### 2. Topic Architecture

All MQTT topics follow this default pattern: `{ProductModel}/{SerialNumber}/{TopicType}`

<table><thead><tr><th>Topic Suffix</th><th>Direction</th><th>Description</th><th width="142">QoS</th><th>Retain</th></tr></thead><tbody><tr><td><code>/data</code></td><td>Device → Server</td><td>Periodic telemetry data (e.g., Voltage, Current)</td><td>0</td><td>No</td></tr><tr><td><code>/cmd</code></td><td>Server → Device</td><td>Commands to device</td><td>0/1</td><td>No</td></tr><tr><td><code>/cdata</code></td><td>Device → Server</td><td>Command execution responses</td><td>0</td><td>No</td></tr><tr><td><code>/mdata</code></td><td>Device → Server</td><td>Device metadata (published on boot)</td><td>0</td><td><strong>Yes</strong></td></tr></tbody></table>

**Example Topics (for SPM02, SN: 9D1024BD51F1):**

* `SPM02/9D1024BD51F1/data`
* `SPM02/9D1024BD51F1/cmd`

***

### 3. Telemetry Data (`/data`)

The device publishes measurement data to the `/data` topic at a configurable interval (default: 30 seconds).

* **Note:** All measurement values are formatted as **Strings** (e.g., `"227.7"`).
* The `TP` field indicates the phase type (`1` for Single-Phase, `3` for Three-Phase). **Developers should parse the payload structure based on the `TP` value.**

#### 3.1 System Information Fields (Common)

These fields are included in all `/data` payloads regardless of the model:

| Field          | Type   | Description                                        |
| -------------- | ------ | -------------------------------------------------- |
| `Post`         | number | Packet sequence counter                            |
| `Time`         | number | Unix timestamp (seconds)                           |
| `IP`           | string | Device IP address                                  |
| `Rssi`         | number | Wi-Fi signal strength (dBm)                        |
| `FWVersion`    | string | Firmware version (e.g., `"5.1.12"`)                |
| `MCUVersion`   | string | MCU firmware version (e.g., `"001.01.10"`)         |
| `SerialNumber` | string | Device MAC/Serial Number                           |
| `ProductModel` | string | Product model (e.g., `"SPM01"`, `"SPM02"`)         |
| `TP`           | number | Phase Type (`1` = Single-Phase, `3` = Three-Phase) |

#### 3.2 Single-Phase Payload (TP: 1)

For single-phase devices (e.g., SPM01), measurement fields have no suffix.

```json
{
  "Post": 927,
  "Time": 1782313081,
  "IP": "192.168.50.188",
  "Rssi": -68,
  "FWVersion": "5.1.14",
  "SerialNumber": "9C0024BD51F1",
  "ProductModel": "SPM01",
  "MCUVersion": "003.00.13",
  "TP": 1,
  "Voltage": "227.6",
  "Current": "0.000",
  "ActivePower": "0.000",
  "ApparentPower": "0.000",
  "PowerFactor": "1.00",
  "Frequency": "50.09",
  "ForwardEnergy": "0.00",
  "ReverseEnergy": "0.00",
  "TotalEnergy": "0.00"
}
```

#### 3.3 Three-Phase Payload (TP: 3)

For three-phase devices (or devices operating in 3-phase mode like SPM02), measurement fields use **X/Y/Z** suffixes.

```json
{
  "Post": 1842,
  "Time": 1782312995,
  "IP": "192.168.50.238",
  "Rssi": -72,
  "FWVersion": "5.1.14",
  "SerialNumber": "50701B597664",
  "ProductModel": "SPM02",
  "MCUVersion": "001.01.01",
  "TP": 3,
  "VoltageX": "226.3",
  "VoltageY": "226.2",
  "VoltageZ": "226.2",
  "CurrentX": "0.000",
  "CurrentY": "0.000",
  "CurrentZ": "0.000",
  "ActivePowerX": "0.000",
  "ActivePowerY": "0.000",
  "ActivePowerZ": "0.000",
  "TotalActivePower": "0.000",
  "ReactivePowerX": "0.000",
  "ReactivePowerY": "0.000",
  "ReactivePowerZ": "0.000",
  "ApparentPowerX": "0.000",
  "ApparentPowerY": "0.000",
  "ApparentPowerZ": "0.000",
  "PowerFactorX": "0.00",
  "PowerFactorY": "0.00",
  "PowerFactorZ": "1.00",
  "UnbalanceLineCurrents": "0",
  "OverallPowerFactor": "0.00",
  "Frequency": "50.01",
  "ForwardEnergyX": "0.85",
  "ForwardEnergyY": "0.02",
  "ForwardEnergyZ": "0.02",
  "TotalForwardEnergy": "0.89",
  "ReverseEnergyX": "0.00",
  "ReverseEnergyY": "0.00",
  "ReverseEnergyZ": "0.00",
  "TotalReverseEnergy": "0.00"
}
```

***

### 4. Metadata (`/mdata`)

Published once upon device boot with the **Retain** flag set. Useful for discovering device basic info without waiting for telemetry.

```json
{
  "product": "EnergySensor-SPM01-9C0024BD51F1",
  "Serialnumber": "9C0024BD51F1",
  "fwVer": "5.1.12"
}
```

***

### 5. Command & Control (`/cmd` & `/cdata`)

#### 5.1 Standard Message Format

**Request (`/cmd`):** A JSON object containing at least the `cmd` string.

```json
{
  "cmd": "location"
}
```

**Response (`/cdata`):** A standardized JSON object returning the execution result.

```json
{
  "ok": true,
  "msg": "location received",
  "event": "location",
  "d": {} 
}
```

* `ok` (boolean): Success or failure.
* `msg` (string): Result description or error message.
* `event` (string): Echoes the requested command.
* `d` (object): Optional. Contains requested data payload.

#### 5.2 Supported Commands Reference

**`getFunctionMap` - Read Device Capabilities**

Reads the 16-bit function bitmap indicating enabled services (e.g., MQTT, HTTP).

* **Request:** `{"cmd": "getFunctionMap"}`
* **Response:**

  ```json
  {
    "ok": true,
    "msg": "",
    "event": "getFunctionMap",
    "d": { "functionMap": 640 }
  }
  ```

**`model` - Read Device Configuration**

Returns a snapshot of the device's network and MQTT configuration.

* **Request:** `{"cmd": "model"}`
* **Response:**

  ```json
  {
    "ok": true,
    "msg": "",
    "event": "model",
    "d": {
      "WN": "Bituo-ext",
      "MH": "broker.emqx.io",
      "MF": true,
      "MP": 8883,
      "MS": true
    }
  }
  ```

**`location` - Identify Device**

Triggers the device LED/Buzzer to flash/beep for 15 seconds.

* **Request:** `{"cmd": "location"}`
* **Response:** `{"ok": true, "msg": "location received", "event": "location"}`

**`zero` - Reset Energy Counters**

⚠️ **Irreversible.** Resets all accumulated energy counters to zero.

* **Request:** `{"cmd": "zero"}`
* **Response:** `{"ok": true, "msg": "zero received", "event": "zero"}`

**`restart` - Reboot Device**

Triggers a soft reboot.

* **Request:** `{"cmd": "restart"}`
* **Response:** `{"ok": true, "msg": "restart received", "event": "restart"}`

**`wifi` - Configure Wi-Fi**

Updates Wi-Fi credentials.

* **Request:**

  ```json
  {
    "cmd": "wifi",
    "ssid": "YourSSID",
    "pass": "YourPassword"
  }
  ```

**`mqtt` - Configure MQTT Broker**

Updates MQTT broker settings.

* **Request:**

  ```json
  {
    "cmd": "mqtt",
    "data": "broker.emqx.io|client_id|1|8883|30|user|pwd"
  }
  ```

  *(Format: `host|clientid|ssl(1/0)|port|interval|username|password`)*

***

### 6. How to Configure MQTTS (TLS/SSL)

The device supports secure MQTT connections over **TLS 1.2** and **TLS 1.3** to ensure data encryption and prevent man-in-the-middle attacks. Follow these steps to configure MQTTS via the embedded Web UI.

#### Step 1: Access the Embedded Web UI

1. Open a web browser and enter the device's IP address (e.g., `http://192.168.50.208`).
2. **Troubleshooting:** If the web page is inaccessible, the HTTP service might be disabled on the device. You can enable it using the **BT Powerlink APP** or the **WeChat Mini APP**:
   * Open the App and connect to the device via Bluetooth.
   * Navigate to **Settings** -> **Forwarding**.
   * Turn on the **HTTP** toggle.

#### Step 2: Upload the CA Certificate

To establish a trusted TLS connection, the device needs the Root CA certificate of your MQTT broker.

1. In the Web UI, navigate to **Edit** -> **Forwarding** -> **Upload MQTT CA certificate**.
2. Click **Choose File** and select your CA certificate file (must be in PEM format, usually `.pem` or `.crt`).
3. Click **Upload**.

#### Step 3: Configure MQTT Broker Settings

1. Navigate to **Edit** -> **Forwarding** -> **MQTT broker**.
2. **Check the `SSL / TLS` box** at the top.
3. Fill in your broker details.

**Example using EMQX Public Broker:**

* **Host:** `broker.emqx.io`
* **Port:** `8883` *(Standard secure MQTT port)*
* **Client ID / Username / Password:** Fill according to your needs.
* **ReportFrequency:** Set your desired interval (e.g., `30` seconds).
* Click **Save MQTT**.

> 💡 **Tip: How to get the EMQX CA Certificate?** If you are using `broker.emqx.io`, you can download their Root CA certificate directly from the EMQX official website (search for "EMQX Public Broker CA download"). Alternatively, you can visit `https://broker.emqx.io` in your browser, click the "Lock" icon in the address bar, view the certificate details, and export the Root CA as a Base64 encoded `.cer` or `.crt` file.

#### Step 4: Reboot to Apply Changes

After saving the configuration, the device must be rebooted for the new TLS settings and certificates to take effect.

1. Look at the top right corner of the Web UI dashboard.
2. You will see a notification: *"Configuration was sent. Enable restart when you are ready to reboot the device."*
3. Check the **"Send restart command"** box. The device will reboot immediately and attempt to connect to your broker using MQTTS.
4. Once rebooted, you can verify the connection status at the top right of the dashboard (it should display `MQTT: Online`).

***

### 7. Appendix: Major Changes from Legacy API (v5.1.14-)

For developers migrating from the older firmware (e.g., v1.1.8) to the new Basic Firmware (5.1.12+), please note the following breaking changes. The architecture has been unified with the BLE standard to improve efficiency and reduce payload sizes.

#### 7.1 Quick Comparison Table

<table><thead><tr><th width="233">Feature / Concept</th><th>Legacy API (v5.1.13-)</th><th>Basic Firmware (v5.1.14+)</th></tr></thead><tbody><tr><td><strong>Topic Prefix</strong></td><td><code>bituotechnik/{Model}/...</code></td><td><code>{Model}/...</code> <em>(Prefix removed)</em></td></tr><tr><td><strong>Command Format</strong></td><td>Uppercase (e.g., <code>RDATA</code>, <code>WINT</code>)</td><td>Lowercase / BLE semantics (e.g., <code>location</code>)</td></tr><tr><td><strong>Request Tracking</strong></td><td>Uses <code>seq</code> (Sequence Number)</td><td><strong>Deprecated</strong>. Uses <code>event</code> field in response</td></tr><tr><td><strong>Response Format</strong></td><td><code>{"result": "SUCCESS", "seq": ...}</code></td><td><code>{"ok": true, "msg": "...", "event": "...", "d": {...}}</code></td></tr><tr><td><strong>Phase Indicator</strong></td><td>Implicit (relies on <code>DeviceType</code>)</td><td>Explicit <code>TP</code> field (<code>1</code> = Single, <code>3</code> = Three-Phase)</td></tr><tr><td><strong>New Telemetry Fields</strong></td><td>N/A</td><td><code>Time</code>, <code>IP</code>, <code>MCUVersion</code></td></tr><tr><td><strong>Metadata (<code>/mdata</code>)</strong></td><td><code>macAddr</code>, <code>fwVer</code></td><td><code>product</code>, <code>Serialnumber</code>, <code>fwVer</code></td></tr></tbody></table>

#### 7.2 Detailed Change Notes

* **Command Architecture (BLE Unification):** The `seq` field is completely removed. Request/response matching is now handled via the `event` field in the response payload. Commands now strictly follow the BLE API semantics.
* **Telemetry Payload (`/data`):** Added the `TP` field to explicitly indicate phase type, replacing the old `DeviceType` logic. Payloads now include `Time` (Unix timestamp), `IP`, and `MCUVersion`. *(Note: Starting from v5.1.14, calculated totals like `TotalActivePower`, `TotalForwardEnergy`, and `TotalReverseEnergy` have been re-introduced to the 3-phase payload).*
* **Metadata (`/mdata`):** The JSON schema has been updated. The legacy `macAddr` field is replaced by `Serialnumber`, and a new `product` string is included.


# mDNS Discovery

{% hint style="info" %}
**Status**: Stable | **Applies to:** SPM / SDM Open Wi-Fi (ESP32-H2 8685 / C6) | **Updated**: 2026-05-26
{% endhint %}

***

### 1. Overview

Bituo smart meters utilize **mDNS (Multicast DNS)** to enable zero-configuration device discovery on local networks. This allows automation gateways, energy management systems (EMS), and mobile apps to automatically detect the meter's IP address and capabilities without manual scanning or static IP assignment.

***

### 2. Applied Product Models

<details>

<summary><strong>Single-Phase (SPM01-xxEW)</strong></summary>

<table><thead><tr><th width="64">#</th><th width="220">Ordering Number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td><strong>SPM01-D2EW</strong></td><td>SPM01 1PN FLEX/63A Wi-Fi (ESP32-8685)</td></tr><tr><td>2</td><td><strong>SPM01-D1EW</strong></td><td>SPM01 1PN MCBM-DM/63A Wi-Fi (ESP32-8685)</td></tr><tr><td>3</td><td><strong>SPM01-U1EW</strong></td><td>SPM01 1PN MCBM-UM/63A Wi-Fi (ESP32-8685)</td></tr></tbody></table>

</details>

<details>

<summary><strong>Split-Phase (SDM02-EW-*)</strong></summary>

<table><thead><tr><th width="64">#</th><th width="220">Ordering Number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td><strong>SDM02-EW-12</strong></td><td>SDM02 Split-Phase SCTA-2×120A/Φ16 Wi-Fi (ESP32-8685)</td></tr><tr><td>2</td><td><strong>SDM02-EW-20</strong></td><td>SDM02 Split-Phase SCTA-2×200A/Φ20 Wi-Fi (ESP32-8685)</td></tr><tr><td>3</td><td><strong>SDM02-EW-10U</strong></td><td>SDM02 Split-Phase SCTA-2×100A/Φ12 Wi-Fi(ESP32-8685)</td></tr></tbody></table>

</details>

<details>

<summary><strong>Three-Phase (SPM02-xxEW / SDM01-EWM-*)</strong></summary>

<table><thead><tr><th width="64">#</th><th width="220">Ordering Number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td><strong>SPM02-D2EW</strong></td><td>SPM02 3PN FLEX/63A Wi-Fi (ESP32-8685)</td></tr><tr><td>2</td><td><strong>SPM02-D1EW</strong></td><td>SPM02 3PN MCBM-DM/63A Wi-Fi (ESP32-8685)</td></tr><tr><td>3</td><td><strong>SPM02-U1EW</strong></td><td>SPM02 3PN MCBM-UM/63A Wi-Fi (ESP32-8685)</td></tr><tr><td>4</td><td><strong>SDM01-EWM-12</strong></td><td>SDM01 SCTA-3×120A/Φ16 Wi-Fi (ESP32-8685) + RS485</td></tr><tr><td>5</td><td><strong>SDM01-EWM-20</strong></td><td>SDM01 SCTA-3×200A/Φ20 Wi-Fi (ESP32-8685) + RS485</td></tr></tbody></table>

</details>

***

### 3. Service Specification

Devices broadcast their presence via mDNS on the local subnet using the following parameters:

<table><thead><tr><th width="220">Parameter</th><th>Value / Format</th></tr></thead><tbody><tr><td><strong>Service Type</strong></td><td><code>_http._tcp.local.</code></td></tr><tr><td><strong>Hostname</strong></td><td><code>EnergySensor-[MODEL]-[VARIANT]-[MAC_UID].local.</code></td></tr><tr><td><strong>Port</strong></td><td><code>80</code> (Web UI / API)</td></tr><tr><td><strong>MAC UID Format</strong></td><td><code>[MAC_ADDRESS_UPPERCASE_NO_SEPARATOR]</code></td></tr></tbody></table>

#### Hostname Field Breakdown

<table><thead><tr><th width="134">Field</th><th width="163">Example</th><th>Description</th></tr></thead><tbody><tr><td><code>MODEL</code></td><td><code>SDM01_3PN</code></td><td>Product model identifier</td></tr><tr><td><code>VARIANT</code></td><td><code>01</code></td><td>Firmware variant code, reflecting differences in HTTP protocol implementation. Includes both Bituo standard versions and customer-customized builds.</td></tr><tr><td><code>MAC_UID</code></td><td><code>45705E597760</code></td><td>Device MAC address, uppercase, no separators</td></tr></tbody></table>

> 💡 **Hostname Example:** `EnergySensor-SDM01_3PN_01-45705E597760.local.`

> ⚠️ **Integration Note:** When filtering discovered devices, match on the `EnergySensor-` prefix, model name, and variant field. The variant identifies the firmware build and HTTP protocol implementation — only connect to variants that have been validated against your integration. Devices with an unrecognized variant should be flagged rather than assumed compatible.

***

### 4. Integration Patterns

mDNS serves as the entry point for various integration protocols. Once the device is discovered, the integration system can establish communication via the following interfaces:

* **Modbus TCP:** Standard port `502` for real-time electrical data polling (ideal for PLCs and industrial gateways).
* **HTTP / REST API:** For system configuration, firmware updates, and status monitoring.
* **WebSocket:** For low-latency, real-time data streaming and event-driven notifications.
* **UDP:** For high-frequency telemetry broadcast in specialized industrial control scenarios.

***

### 5. Typical Use Cases

mDNS discovery is essential for automated energy management systems, particularly when the meter acts as the primary data source for the entire site:

* **Dynamic Load Balancing (DLB):** EV chargers and heat pumps query the meter via mDNS to monitor total household consumption and adjust charging power in real-time to prevent grid overload.
* **Export Limiting:** Solar inverters detect the grid-tie meter via mDNS to monitor real-time import/export power and throttle inverter output to comply with grid feed-in regulations.
* **Energy Gateway Integration:** Local energy gateways discover all meters on the network via mDNS — including main incoming meters, sub-meters, and circuit-level sensors — and automatically map them during commissioning, eliminating the need for manual IP configuration across complex multi-meter sites.

***

### 6. Verification

The simplest way to verify mDNS is working is with a phone app on the same Wi-Fi network.

**Recommended App:** *Service Browser* (Android) — search and install from the Play Store.

**Steps:**

1. Connect your phone to the **same Wi-Fi network** as the meter.
2. Open Service Browser and browse to **World Wide Web HTTP** (`_http._tcp`).
3. Look for a device named `EnergySensor-{Model}_{VariantCode}-{MAC}`.
4. Tap the entry — you should see the resolved **IPv4 address and port 80** (e.g., `192.168.50.135:80`).

If the device appears with a valid IP, mDNS is functioning correctly.

> Other verification methods are also available, including command-line tools (`ping <hostname>.local`, `dns-sd -B _http._tcp` on macOS/Linux) and desktop packet capture tools such as Wireshark (filter: `mdns`). Refer to the Troubleshooting section for details.


# Modbus TCP Map - ESP32-8685

{% hint style="info" %}
**Status:** Draft| **Applies to:** SPM/SDM Open WiFi (ESP32-8685)  | **Firmware:** 5.1.11+ | **Updated:** 2026-06-18
{% endhint %}

### 1. Overview

This page documents the Modbus TCP over Wi-Fi interface for the Bituo SPM/SDM series smart meters. It covers connection requirements and the full register map.

***

### 2. Applied Product Models

This page documents the **Modbus TCP over Wi-Fi** interface for the Bituo SPM/SDM series smart meters. It covers connection requirements and the full register map.

<details>

<summary><strong>Single-Phase (SPM01-xxEW)</strong></summary>

<table><thead><tr><th width="64">#</th><th width="220">Ordering Number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td><strong>SPM01-D2EW</strong></td><td>SPM01 1PN FLEX/63A Wi-Fi (ESP32-8685)</td></tr><tr><td>2</td><td><strong>SPM01-D1EW</strong></td><td>SPM01 1PN MCBM-DM/63A Wi-Fi (ESP32-8685)</td></tr><tr><td>3</td><td><strong>SPM01-U1EW</strong></td><td>SPM01 1PN MCBM-UM/63A Wi-Fi (ESP32-8685)</td></tr></tbody></table>

</details>

<details>

<summary><strong>Split-Phase (SDM02-EW-*)</strong></summary>

<table><thead><tr><th width="64">#</th><th width="220">Ordering Number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td><strong>SDM02-EW-12</strong></td><td>SDM02 Split-Phase SCTA-2×120A/Φ16 Wi-Fi (ESP32-8685)</td></tr><tr><td>2</td><td><strong>SDM02-EW-20</strong></td><td>SDM02 Split-Phase SCTA-2×200A/Φ20 Wi-Fi (ESP32-8685)</td></tr><tr><td>3</td><td><strong>SDM02-EW-10U</strong></td><td>SDM02 Split-Phase SCTA-2×100A/Φ12 Wi-Fi(ESP32-8685)</td></tr></tbody></table>

</details>

<details>

<summary><strong>Three-Phase (SPM02-xxEW / SDM01-EWM-*)</strong></summary>

<table><thead><tr><th width="64">#</th><th width="220">Ordering Number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td><strong>SPM02-D2EW</strong></td><td>SPM02 3PN FLEX/63A Wi-Fi (ESP32-8685)</td></tr><tr><td>2</td><td><strong>SPM02-D1EW</strong></td><td>SPM02 3PN MCBM-DM/63A Wi-Fi (ESP32-8685)</td></tr><tr><td>3</td><td><strong>SPM02-U1EW</strong></td><td>SPM02 3PN MCBM-UM/63A Wi-Fi (ESP32-8685)</td></tr><tr><td>4</td><td><strong>SDM01-EWM-12</strong></td><td>SDM01 SCTA-3×120A/Φ16 Wi-Fi (ESP32-8685) + RS485</td></tr><tr><td>5</td><td><strong>SDM01-EWM-20</strong></td><td>SDM01 SCTA-3×200A/Φ20 Wi-Fi (ESP32-8685) + RS485</td></tr></tbody></table>

</details>

***

### 3. Connection & Protocol Notes

> **💡 Default Connection Parameters:** **Protocol:** Modbus TCP | **Port:** 502 | **Slave ID:** `1` | **Byte Order:** Big-Endian (ABCD)

{% hint style="warning" %}
**Critical: Single-Connection Limitation** The device firmware supports **only ONE concurrent TCP connection**\*\* and actively resets the socket after each read request.

**Integration Requirement:** Open a new TCP connection before each read operation and close it immediately afterward. A minimum delay of **150ms** between consecutive reads is recommended to prevent device overload.
{% endhint %}

**Supported Function Codes:**

* `0x03` — Read Holding Registers
* `0x04` — Read Input Registers *(Both function codes return identical data on this device.)*
* `0x06` — Write Single Register (Used for Control Commands only. )

***

### 4. Register Map

#### 4.1 Product Identification (Base Address: 978)

*This section is identical across all Single-Phase, Split-Phase, and Three-Phase devices.*

*Note: String fields are encoded as continuous UTF-8 byte streams. Register count = `Bytes ÷ 2`.*

<table><thead><tr><th width="110">Address (DEC)</th><th width="115">Address (HEX)</th><th width="160">Description</th><th width="90">Func Code</th><th width="80">R/W</th><th width="80">Bytes</th><th width="90">Registers</th><th width="110">Data Type</th><th width="240">Notes</th></tr></thead><tbody><tr><td>978</td><td><code>0x03D2</code></td><td>MAC Address</td><td>03, 04</td><td>R</td><td>12</td><td>6</td><td>UTF-8 String</td><td>Device Wi-Fi MAC address.</td></tr><tr><td>984</td><td><code>0x03D8</code></td><td>Model</td><td>03, 04</td><td>R</td><td>10</td><td>5</td><td>UTF-8 String</td><td>e.g., "SDM01_3PN"</td></tr><tr><td>989</td><td><code>0x03DD</code></td><td>MCU Version</td><td>03, 04</td><td>R</td><td>10</td><td>5</td><td>UTF-8 String</td><td>e.g., "5.1.11"</td></tr><tr><td>994</td><td><code>0x03E2</code></td><td>RSSI</td><td>03, 04</td><td>R</td><td>2</td><td>1</td><td>UINT16</td><td>Wi-Fi signal strength (dBm). Typical range: -30 ~ -90.</td></tr><tr><td>995</td><td><code>0x03E3</code></td><td>System Time</td><td>03, 04</td><td>R</td><td>4</td><td>2</td><td>UINT32</td><td>Unix timestamp (seconds since 1970-01-01).</td></tr><tr><td>997</td><td><code>0x03E5</code></td><td>Firmware Version</td><td>03, 04</td><td>R</td><td>6</td><td>3</td><td>UTF-8 String</td><td>Format: "x.x.x"</td></tr></tbody></table>

#### 4.2 Basic Metering Data

*All FLOAT32 values occupy 2 Modbus registers (4 bytes). Byte order: Big-Endian (ABCD). Please select the tab corresponding to your device type.*

{% tabs %}
{% tab title="Single-Phase" %}

<table><thead><tr><th width="110">Address (DEC)</th><th width="115">Address (HEX)</th><th width="230">Description</th><th width="90">Func Code</th><th width="55">R/W</th><th width="100">Data Type</th><th width="130">Range</th><th>Unit</th></tr></thead><tbody><tr><td>1000</td><td><code>0x03E8</code></td><td>Voltage</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 – 1000</td><td>V</td></tr><tr><td>1002</td><td><code>0x03EA</code></td><td>Current</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 – 1000</td><td>A</td></tr><tr><td>1004</td><td><code>0x03EC</code></td><td>Active Power</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1000 – 1000</td><td>kW</td></tr><tr><td>1006</td><td><code>0x03EE</code></td><td>Power Factor</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1.0 – 1.0</td><td>—</td></tr><tr><td>1008</td><td><code>0x03F0</code></td><td>Frequency</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 – 1000</td><td>Hz</td></tr><tr><td>1010</td><td><code>0x03F2</code></td><td>Import Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1012</td><td><code>0x03F4</code></td><td>Export Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1014</td><td><code>0x03F6</code></td><td>Total Active Energy (Import + Export)</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr></tbody></table>
{% endtab %}

{% tab title="Split-Phase" %}

<table><thead><tr><th width="110">Address (DEC)</th><th width="115">Address (HEX)</th><th width="230">Description</th><th width="90">Func Code</th><th width="55">R/W</th><th width="100">Data Type</th><th width="130">Range</th><th>Unit</th></tr></thead><tbody><tr><td>1000</td><td><code>0x03E8</code></td><td>Voltage L1-N</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 – 1000</td><td>V</td></tr><tr><td>1002</td><td><code>0x03EA</code></td><td>Voltage L2-N</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 – 1000</td><td>V</td></tr><tr><td>1006</td><td><code>0x03EE</code></td><td>Current L1</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 – 1000</td><td>A</td></tr><tr><td>1008</td><td><code>0x03F0</code></td><td>Current L2</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 – 1000</td><td>A</td></tr><tr><td>1012</td><td><code>0x03F4</code></td><td>Active Power L1</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1000 – 1000</td><td>kW</td></tr><tr><td>1014</td><td><code>0x03F6</code></td><td>Active Power L2</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1000 – 1000</td><td>kW</td></tr><tr><td>1018</td><td><code>0x03FA</code></td><td>Reactive Power L1</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1000 – 1000</td><td>kVAR</td></tr><tr><td>1020</td><td><code>0x03FC</code></td><td>Reactive Power L2</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1000 – 1000</td><td>kVAR</td></tr><tr><td>1024</td><td><code>0x0400</code></td><td>Apparent Power L1</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1000 – 1000</td><td>kVA</td></tr><tr><td>1026</td><td><code>0x0402</code></td><td>Apparent Power L2</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1000 – 1000</td><td>kVA</td></tr><tr><td>1030</td><td><code>0x0406</code></td><td>Power Factor L1</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1.0 – 1.0</td><td>—</td></tr><tr><td>1032</td><td><code>0x0408</code></td><td>Power Factor L2</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1.0 – 1.0</td><td>—</td></tr><tr><td>1036</td><td><code>0x040C</code></td><td>Average Voltage L-N</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 – 1000</td><td>V</td></tr><tr><td>1038</td><td><code>0x040E</code></td><td>Average Line Current</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 – 1000</td><td>A</td></tr><tr><td>1040</td><td><code>0x0410</code></td><td>Unbalanced Line Currents</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-300 – 300</td><td>%</td></tr><tr><td>1042</td><td><code>0x0412</code></td><td>Total Line Currents</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 – 3000</td><td>A</td></tr><tr><td>1044</td><td><code>0x0414</code></td><td>Total Active Power</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-3000 – 3000</td><td>kW</td></tr><tr><td>1046</td><td><code>0x0416</code></td><td>Total Reactive Power</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-3000 – 3000</td><td>kVAR</td></tr><tr><td>1048</td><td><code>0x0418</code></td><td>Total Apparent Power</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-3000 – 3000</td><td>kVA</td></tr><tr><td>1050</td><td><code>0x041A</code></td><td>Total Power Factor</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1.0 – 1.0</td><td>—</td></tr><tr><td>1052</td><td><code>0x041C</code></td><td>Frequency</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 – 1000</td><td>Hz</td></tr><tr><td>1054</td><td><code>0x041E</code></td><td>Total Import Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1056</td><td><code>0x0420</code></td><td>Total Export Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1058</td><td><code>0x0422</code></td><td>Total Import &#x26; Export Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1060</td><td><code>0x0424</code></td><td>L1 Import Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1062</td><td><code>0x0426</code></td><td>L1 Export Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1064</td><td><code>0x0428</code></td><td>L1 Import &#x26; Export Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1066</td><td><code>0x042A</code></td><td>L2 Import Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1068</td><td><code>0x042C</code></td><td>L2 Export Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1070</td><td><code>0x042E</code></td><td>L2 Import &#x26; Export Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr></tbody></table>
{% endtab %}

{% tab title="Three-Phase" %}

<table><thead><tr><th width="110">Address (DEC)</th><th width="115">Address (HEX)</th><th width="240">Description</th><th width="90">Func Code</th><th width="55">R/W</th><th width="100">Data Type</th><th width="130">Range</th><th>Unit</th></tr></thead><tbody><tr><td>1000</td><td><code>0x03E8</code></td><td>Voltage A-N</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 – 1000</td><td>V</td></tr><tr><td>1002</td><td><code>0x03EA</code></td><td>Voltage B-N</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 – 1000</td><td>V</td></tr><tr><td>1004</td><td><code>0x03EC</code></td><td>Voltage C-N</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 – 1000</td><td>V</td></tr><tr><td>1006</td><td><code>0x03EE</code></td><td>Current A</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 – 1000</td><td>A</td></tr><tr><td>1008</td><td><code>0x03F0</code></td><td>Current B</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 – 1000</td><td>A</td></tr><tr><td>1010</td><td><code>0x03F2</code></td><td>Current C</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 – 1000</td><td>A</td></tr><tr><td>1012</td><td><code>0x03F4</code></td><td>Active Power A</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1000 – 1000</td><td>kW</td></tr><tr><td>1014</td><td><code>0x03F6</code></td><td>Active Power B</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1000 – 1000</td><td>kW</td></tr><tr><td>1016</td><td><code>0x03F8</code></td><td>Active Power C</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1000 – 1000</td><td>kW</td></tr><tr><td>1018</td><td><code>0x03FA</code></td><td>Reactive Power A</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1000 – 1000</td><td>kVAR</td></tr><tr><td>1020</td><td><code>0x03FC</code></td><td>Reactive Power B</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1000 – 1000</td><td>kVAR</td></tr><tr><td>1022</td><td><code>0x03FE</code></td><td>Reactive Power C</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1000 – 1000</td><td>kVAR</td></tr><tr><td>1024</td><td><code>0x0400</code></td><td>Apparent Power A</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1000 – 1000</td><td>kVA</td></tr><tr><td>1026</td><td><code>0x0402</code></td><td>Apparent Power B</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1000 – 1000</td><td>kVA</td></tr><tr><td>1028</td><td><code>0x0404</code></td><td>Apparent Power C</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1000 – 1000</td><td>kVA</td></tr><tr><td>1030</td><td><code>0x0406</code></td><td>Power Factor A</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1.0 – 1.0</td><td>—</td></tr><tr><td>1032</td><td><code>0x0408</code></td><td>Power Factor B</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1.0 – 1.0</td><td>—</td></tr><tr><td>1034</td><td><code>0x040A</code></td><td>Power Factor C</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1.0 – 1.0</td><td>—</td></tr><tr><td>1036</td><td><code>0x040C</code></td><td>Average Voltage L-N</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 – 1000</td><td>V</td></tr><tr><td>1038</td><td><code>0x040E</code></td><td>Average Line Current</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 – 1000</td><td>A</td></tr><tr><td>1040</td><td><code>0x0410</code></td><td>Unbalanced Line Currents</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-300 – 300</td><td>%</td></tr><tr><td>1042</td><td><code>0x0412</code></td><td>Total Line Currents</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 – 3000</td><td>A</td></tr><tr><td>1044</td><td><code>0x0414</code></td><td>Total Active Power</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-3000 – 3000</td><td>kW</td></tr><tr><td>1046</td><td><code>0x0416</code></td><td>Total Reactive Power</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-3000 – 3000</td><td>kVAR</td></tr><tr><td>1048</td><td><code>0x0418</code></td><td>Total Apparent Power</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-3000 – 3000</td><td>kVA</td></tr><tr><td>1050</td><td><code>0x041A</code></td><td>Total Power Factor</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>-1.0 – 1.0</td><td>—</td></tr><tr><td>1052</td><td><code>0x041C</code></td><td>Frequency</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>0 – 1000</td><td>Hz</td></tr><tr><td>1054</td><td><code>0x041E</code></td><td>Total Import Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1056</td><td><code>0x0420</code></td><td>Total Export Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1058</td><td><code>0x0422</code></td><td>Total Import &#x26; Export Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1060</td><td><code>0x0424</code></td><td>Phase A Import Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1062</td><td><code>0x0426</code></td><td>Phase A Export Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1064</td><td><code>0x0428</code></td><td>Phase A Import &#x26; Export Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1066</td><td><code>0x042A</code></td><td>Phase B Import Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1068</td><td><code>0x042C</code></td><td>Phase B Export Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1070</td><td><code>0x042E</code></td><td>Phase B Import &#x26; Export Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1072</td><td><code>0x0430</code></td><td>Phase C Import Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1074</td><td><code>0x0432</code></td><td>Phase C Export Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr><tr><td>1076</td><td><code>0x0434</code></td><td>Phase C Import &#x26; Export Active Energy</td><td>03, 04</td><td>R</td><td>FLOAT32</td><td>±1,999,999,999</td><td>kWh</td></tr></tbody></table>
{% endtab %}
{% endtabs %}

***

### 5. Control Commands (Unicast)

Send these commands to a specific device's IP address using Modbus TCP with the target **Slave ID**.

{% hint style="warning" %}
**Write-Only Commands:** These registers are write-only and use Function Code \`0x06\` (Write Single Register). They are not readable. Sending an incorrect write value will have no effect.
{% endhint %}

<table><thead><tr><th width="101">Address (DEC)</th><th width="111">Address (HEX)</th><th width="240">Description</th><th width="98">Func Code</th><th width="89">R/W</th><th width="100">Data Type</th><th>Write Value</th></tr></thead><tbody><tr><td>10000</td><td><code>0x2710</code></td><td>Trigger LED Blinking (Device Locating)</td><td>06</td><td>W</td><td>UINT16</td><td><code>0x5055</code> (20565)</td></tr><tr><td>10001</td><td><code>0x2711</code></td><td>Reset Energy Accumulators</td><td>06</td><td>W</td><td>UINT16</td><td><code>0x51AA</code> (20906)</td></tr></tbody></table>

> 🔍 **Feature: Device Locating via LED** When multiple meters are installed in a dense electrical panel, send `0x5055` to a specific device's Slave ID. The target meter's **LED will blink rapidly for 15 seconds**, allowing field engineers to visually identify the physical device corresponding to that IP/Slave ID.

***


# BLE Basic API

## BLE API Reference

**Document Version:** V0.1 Preliminary | **Last Updated:** 2026-04-21 | **Accessible Scope:** Public

This document is intended for third-party Apps, gateways, or debugging tools to interface with the device's BLE API. It describes only the externally visible protocols and does not cover internal implementations.

### Applied Product Models

<table><thead><tr><th width="76">#</th><th width="214">Ordering Number</th><th>Description</th></tr></thead><tbody><tr><td>1</td><td><strong>SPM01-D2EW</strong></td><td>SPM01 1PN FLEX/63A Open BLE+Wi-Fi</td></tr><tr><td>2</td><td><strong>SPM01-D1EW</strong></td><td>SPM01 1PN MCBM-BM/63A Open BLE+Wi-Fi</td></tr><tr><td>3</td><td><strong>SPM01-U1EW</strong></td><td>SPM01 1PN MCBM-TM/63A Open BLE+Wi-Fi</td></tr><tr><td>4</td><td><strong>SPM02-D2EW</strong></td><td>SPM02 3PN FLEX/63A Open BLE+Wi-Fi</td></tr><tr><td>5</td><td><strong>SPM02-D1EW</strong></td><td>SPM02 3PN MCBM-BM/63A Open BLE+Wi-Fi</td></tr><tr><td>6</td><td><strong>SPM02-U1EW</strong></td><td>SPM02 3PN MCBM-TM/63A Open BLE+Wi-Fi</td></tr><tr><td>7</td><td><strong>SDM01-EWM-12</strong></td><td>SDM01 SCTA-3×120A/Φ16 Wi-Fi (ESP32) + RS485</td></tr><tr><td>8</td><td><strong>SDM01-EWM-20</strong></td><td>SDM01 SCTA-3×200A/Φ20 Wi-Fi (ESP32) + RS485</td></tr><tr><td>9</td><td><strong>SDM01-EWM-12-BKW</strong></td><td>SDM01 SCTA-3x120A/Φ16 Wi-Fi (ESP32) + RS485 BKW</td></tr></tbody></table>

***

### 1. Connection Information

#### 1.1 Device Broadcast Name

* **Naming Rule:** `<Product Model>-<Device Serial Number>`
* **Example:** `SPM01A-1234567890AB`

#### 1.2 GATT Services and Characteristics

* **Primary Service UUID:** `0000A002-0000-1000-8000-00805F9B34FB`
* **Read Characteristic UUID:** `0000C304-0000-1000-8000-00805F9B34FB`
* **Write Characteristic UUID:** `0000C303-0000-1000-8000-00805F9B34FB`
* **Notify Characteristic UUID:** `0000C305-0000-1000-8000-00805F9B34FB`

#### 1.3 Interaction Channel Description

* The client sends commands via the **Write Characteristic**.
* The device returns processing results via the **Notify Characteristic**.
* **Recommendation:** Subscribe to the Notify Characteristic immediately after connection.
* The maximum MTU can reach up to 512 (the actual effective value depends on the connection negotiation result).

***

### 2. Standard Interaction Flow

#### 2.1 Flow Overview

1. Scan and connect to the device.
2. Subscribe to the Notify Characteristic.
3. Send the unlock command (`cmd=pass`).
4. Send business commands after successful unlocking.
5. Receive the result for each command from the Notify Characteristic.

#### 2.2 Unlock Requirements

* In an un-unlocked state, most business commands will be rejected.
* The unlock command must include the password field `pas`.
* After a successful unlock, subsequent `cmd` requests within the current BLE connection session do not need to carry `pas` and `auth` by default.
* If unlocking fails, a "Password Error" or "Please unlock" prompt is returned.

#### 2.3 Phone Binding Authentication (Optional)

If the device has phone authentication enabled:

* It is recommended to include `auth` in the unlock command during the first authentication.
* An authentication error is returned if `auth` does not match.
* For the initial binding scenario, `auth` can be written in the unlock command.

***

### 3. Request & Response Specification

#### 3.1 Common Request Fields (Client -> Device)

* `cmd`: Command word (Required).
* `pas`: BLE password. Required only for the initial verification (`cmd=pass`).
* `auth`: Authentication identifier. Recommended during initial verification (if authentication is enabled).
* **Session Rule:** After successful initial verification, subsequent commands within the same connection session do not need to carry `pas` and `auth`.

#### 3.2 Common Response Fields (Device -> Client)

* `ok`: Boolean, indicates whether the request was processed successfully.
* `msg`: String, processing result description.
* `event`: String (Optional), usually echoes the command word.
* `d`: Object (Optional), appears only when query commands return data.

#### 3.3 Common Failure Semantics

* `Password Error`: Incorrect password.
* `Please unlock`: Device is not unlocked.
* `auth error`: Incorrect authentication field.
* `not authenticated`: Authentication failed.
* `illegal cmd`: Command not supported.

***

### 4. Command API Details

#### 4.1 Initial Handshake

* **Purpose:** Unlock session, change password, set session persistence, and bind initial authentication identifier.
* **Fields:**
  * `cmd`: Fixed as `pass`.
  * `pas`: Current BLE password (Required).
  * `newpas`: New password (Optional, max 16 characters).
  * `continue`: Keep session alive (Optional, Boolean). If omitted, every communication requires a handshake.
  * `auth`: Authentication identifier (Optional, max 40 characters).

**Request Example:**

```json
{
  "cmd": "pass",
  "pas": "123456",
  "continue": true
}
```

**Response Example (Success):**

```json
{
  "ok": true,
  "msg": "Password Correct",
  "event": "pass"
}
```

#### 4.2 Reboot

* **Purpose:** Trigger the device reboot process.
* **Fields:**
  * `cmd`: Fixed as `restart`.

**Request Example:**

```json
{
  "cmd": "restart"
}
```

#### 4.3 Device Location

* **Purpose:** Trigger location processing. The device indicator will flash at 4Hz for 15 seconds.
* **Fields:**
  * `cmd`: Fixed as `location`.

**Request Example:**

```json
{
  "cmd": "location"
}
```

#### 4.4 Unbind

* **Purpose:** Clear the bound authentication status.
* **Fields:**
  * `cmd`: Fixed as `resetauth`.

**Request Example:**

```json
{
  "cmd": "resetauth"
}
```

#### 4.5 Set MQTT Topic 1

* **Purpose:** Set the first group of MQTT topic parameters.
* **Fields:**
  * `cmd`: Fixed as `topic1`.
  * `topic_post`: Uplink topic.
  * `topic_set`: Downlink control topic.

**Request Example:**

```json
{
  "cmd": "topic1",
  "topic_post": "dev/up",
  "topic_set": "dev/down"
}
```

#### 4.6 Set MQTT Topic 2

* **Purpose:** Set the second group of MQTT topic parameters.
* **Fields:**
  * `cmd`: Fixed as `topic2`.
  * `topic_response`: Response topic.
  * `topic_metadata`: Metadata topic.

**Request Example:**

```json
{
  "cmd": "topic2",
  "topic_response": "dev/resp",
  "topic_metadata": "dev/meta"
}
```

#### 4.7 Unlock Read Characteristic

* **Purpose:** Enter readable state to prepare for subsequent status data reading.
* **Fields:**
  * `cmd`: Fixed as `read`.
  * `continue`: Default is read once. Add this field (`true`) for continuous reading (Optional).

**Request Example:**

```json
{
  "cmd": "read",
  "continue": true
}
```

#### 4.8 Clear Energy Data

* **Purpose:** Clear all accumulated energy data (Irreversible).
* **Fields:**
  * `cmd`: Fixed as `zero`.

**Request Example:**

```json
{
  "cmd": "zero"
}
```

#### 4.11 Get Function Map

* **Purpose:** Read the `functionMap` (16-bit feature bitmap).
* **Fields:**
  * `cmd`: Fixed as `getFunctionMap`.

**Request Example:**

```json
{
  "cmd": "getFunctionMap"
}
```

**Response Example:**

```json
{
  "ok": true,
  "msg": "",
  "event": "getFunctionMap",
  "d": {
    "functionMap": 37376
  }
}
```

**Bit Definition Table (Bit 15 is the highest bit):**

| Bit | Function   | Description             |
| --- | ---------- | ----------------------- |
| 15  | Modbus TCP | `1=Enable`, `0=Disable` |
| 14  | TLS Enable | `1=Enable`, `0=Disable` |
| 13  | UDP        | `1=Enable`, `0=Disable` |
| 11  | WebSocket  | `1=Enable`, `0=Disable` |
| 9   | MQTT       | `1=Enable`, `0=Disable` |
| 7   | HTTP       | `1=Enable`, `0=Disable` |
| 5   | LoRaWAN    | `1=Enable`, `0=Disable` |

#### 4.12 TLS Multiplexing Status

* **Purpose:** Read the Modbus TLS multiplexing status value.
* **Fields:**
  * `cmd`: Fixed as `getModbusTlsMuxSetupStatus`.

**Response Example:**

```json
{
  "ok": true,
  "msg": "",
  "event": "getModbusTlsMuxSetupStatus",
  "d": {
    "modbusTlsMuxSetupStatus": 1
  }
}
```

**Status Value Description:**

* `0`: `MODBUS_TLS_MUX_SETUP_IDLE` - Uninitialized (e.g., Wi-Fi disconnected, feature disabled).
* `1`: `MODBUS_TLS_MUX_SETUP_PLAIN_OK` - Started successfully in plaintext (due to incomplete certificates).
* `2`: `MODBUS_TLS_MUX_SETUP_TLS_OK` - TLS started successfully.
* `3`: `MODBUS_TLS_MUX_SETUP_TLS_CERT` - Certificate/Key file error.
* `4`: `MODBUS_TLS_MUX_SETUP_TLS_SOCK` - TLS socket/bind/listen failed.
* `5`: `MODBUS_TLS_MUX_SETUP_PLAIN_FAIL` - Plaintext startup failed.

#### 4.23 Set Function Map

* **Purpose:** Directly write the `functionMap` value.
* **Fields:**
  * `cmd`: Fixed as `functionMap`.
  * `value`: 16-bit integer.

**Request Example:**

```json
{
  "cmd": "functionMap",
  "value": 37376
}
```

#### 4.24 Data Format

* **Purpose:** Set the message reporting format. `0` represents BT format, `1` represents common format.
* **Fields:**
  * `cmd`: Fixed as `commonmode`.
  * `value`: Mode value.

**Request Example:**

```json
{
  "cmd": "commonmode",
  "value": 0
}
```

#### 4.25 Factory Reset

* **Purpose:** Clear configuration and trigger a reboot.
* **Fields:**
  * `cmd`: Fixed as `reset`.

**Request Example:**

```json
{
  "cmd": "reset"
}
```

#### 4.26 Wi-Fi Configuration

* **Purpose:** Set Wi-Fi connection parameters.
* **Fields:**
  * `cmd`: Fixed as `wifi`.
  * `ssid`: Wi-Fi Name (<=64 chars).
  * `pass`: Wi-Fi Password (<=64 chars).

**Request Example:**

```json
{
  "cmd": "wifi",
  "ssid": "OfficeWiFi",
  "pass": "12345678"
}
```

#### 4.27 MQTT Configuration

* **Purpose:** Configure MQTT. Using `mqtr` will additionally trigger a reboot.
* **Fields:**
  * `cmd`: `mqtt` or `mqtr`.
  * `data`: Formatted as `host|clientid|ssl|port|interval|username|password`.

**Request Example:**

```json
{
  "cmd": "mqtt",
  "data": "broker.example.com|dev01|1|8883|5|user|pwd"
}
```

#### 4.28 Start Certificate Writing

* **Purpose:** Create/clear the certificate file and prepare for fragmented writing.
* **Fields:**
  * `cmd`: Fixed as `cafilestart`.
  * `filename`: Target certificate file.

**Request Example:**

```json
{
  "cmd": "cafilestart",
  "filename": "/mqtt.pem"
}
```

#### 4.29 Write Certificate Fragment

* **Purpose:** Write a fragment of the certificate content.
* **Fields:**
  * `cmd`: Fixed as `cafiledata`.
  * `cadata`: Certificate fragment string. Fixed size of 128 bytes (no padding needed for the last packet).

**Request Example:**

```json
{
  "cmd": "cafiledata",
  "cadata": "-----BEGIN CERTIFICATE-----"
}
```

#### 4.30 Add UDP Target

* **Purpose:** Add a new UDP upload target.
* **Fields:**
  * `cmd`: Fixed as `udp`.
  * `IpAddress`: Target IP.
  * `localUdpPort`: Target port.

**Request Example:**

```json
{
  "cmd": "udp",
  "IpAddress": "192.168.1.100",
  "localUdpPort": 9000
}
```

#### 4.31 OTA Status

* **Purpose:** Query the OTA status.
* **Fields:**
  * `cmd`: Fixed as `checkota`.

**Response Example:**

```json
{
  "ok": true,
  "msg": "",
  "event": "checkota",
  "d": {
    "otastatus": 1
  }
}
```

**`otastatus` Value Description:**

* `200`: Update package available.
* `404`: No update package available (already on the latest version).
* `-2`: OTA URL not configured.
* *Other values*: HTTP/Network error codes (e.g., connection failed, timeout).

#### 4.32 OTA Progress

* **Purpose:** Read the OTA progress percentage.
* **Fields:**
  * `cmd`: Fixed as `otaprogress`.

**Response Example:**

```json
{
  "ok": true,
  "msg": "",
  "event": "otaprogress",
  "d": {
    "otaprogress": 60
  }
}
```

#### 4.33 Start OTA

* **Purpose:** Start the OTA task.
* **Fields:**
  * `cmd`: Fixed as `startota`.

**Request Example:**

```json
{
  "cmd": "startota"
}
```

#### 4.34 Delete UDP Target

* **Purpose:** Delete an existing UDP target.
* **Fields:**
  * `cmd`: Fixed as `deleteudp`.
  * `IpAddress`: Target IP.
  * `localUdpPort`: Target port.

**Request Example:**

```json
{
  "cmd": "deleteudp",
  "IpAddress": "192.168.1.100",
  "localUdpPort": 9000
}
```

#### 4.35 UDP List

* **Purpose:** Read the list of UDP targets.
* **Fields:**
  * `cmd`: Fixed as `udpdata`.

**Response Example:**

```json
{
  "ok": true,
  "msg": "",
  "event": "udpdata",
  "d": {
    "items": []
  }
}
```

#### 4.36 Enable HTTP

* **Purpose:** Enable the HTTP bit.
* **Fields:**
  * `cmd`: Fixed as `enablehttp`.

**Request Example:**

```json
{
  "cmd": "enablehttp"
}
```

#### 4.37 Enable WebSocket

* **Purpose:** Enable/Disable the WebSocket bit.
* **Fields:**
  * `cmd`: Fixed as `enablewebsocket`.
  * `enable`: `true` to enable, `false` to disable.

**Request Example:**

```json
{
  "cmd": "enablewebsocket",
  "enable": true
}
```

#### 4.38 Enable Modbus TCP

* **Purpose:** Enable/Disable the Modbus TCP bit.
* **Fields:**
  * `cmd`: Fixed as `enablemodbustcp`.
  * `enable`: `true` to enable, `false` to disable.

**Request Example:**

```json
{
  "cmd": "enablemodbustcp",
  "enable": true
}
```

#### 4.39 Enable TLS

* **Purpose:** Enable/Disable the TLS bit.
* **Fields:**
  * `cmd`: Fixed as `enabletls`.
  * `enable`: `true` to enable, `false` to disable.

**Request Example:**

```json
{
  "cmd": "enabletls",
  "enable": true
}
```

#### 4.40 Modify BLE Password

* **Purpose:** Modify the BLE password.
* **Fields:**
  * `cmd`: Fixed as `blepassword`.
  * `old`: Old password.
  * `new`: New password (<=16 chars).

**Request Example:**

```json
{
  "cmd": "blepassword",
  "old": "123456",
  "new": "654321"
}
```

#### 4.41 Modbus Parameters

* **Purpose:** Set serial Modbus communication parameters.
* **Fields:**
  * `cmd`: Fixed as `modbus`.
  * `baud`: Baud rate.
  * `parityStop`: Parity/Stop bits.
  * `address`: Slave address.

**Request Example:**

```json
{
  "cmd": "modbus",
  "baud": 9600,
  "parityStop": 0,
  "address": 1
}
```

#### 4.42 Device Name

* **Purpose:** Set the device name.
* **Fields:**
  * `cmd`: Fixed as `deviceName`.
  * `name`: Device name (<=30 chars).

**Request Example:**

```json
{
  "cmd": "deviceName",
  "name": "RoomMeter01"
}
```

#### 4.45 Read Configuration

* **Purpose:** Read the comprehensive configuration snapshot of the device.
* **Fields:**
  * `cmd`: Fixed as `model`.
  * `type`: Optional refresh type.

**Request Example:**

```json
{
  "cmd": "model",
  "type": 1
}
```

**Response Example:**

```json
{
  "ok": true,
  "msg": "",
  "event": "model",
  "d": {
    "WN": "OfficeWiFi",
    "MH": "broker.example.com"
  }
}
```

#### 4.46 Read MQTT Data

* **Purpose:** Read MQTT related topics and account information.
* **Fields:**
  * `cmd`: Fixed as `mqttdata`.

**Request Example:**

```json
{
  "cmd": "mqttdata"
}
```

**Response Example:**

```json
{
  "ok": true,
  "msg": "",
  "event": "mqttdata",
  "d": {
    "TP": "dev/up",
    "TC": "dev/down"
  }
}
```

***

### 5. Integration Notes

* It is recommended to uniformly use **UTF-8 encoded JSON text** for all requests.
* Always confirm that the Notify Characteristic is subscribed to before sending commands.
* After a successful initial `cmd=pass`, subsequent commands within the same connection session do not need to carry `pas` and `auth`.
* If the device returns `Please unlock` or `not authenticated`, you must re-execute the initial verification process.
* Supported commands may vary by model. It is recommended to perform capability probing using query commands.

***

### 6. Version & Compatibility

* **Backward Compatibility Recommendation:** The response structure is fixed as `ok / msg / event / d`.
* During external integration, it is recommended to implement failure retries and error prompts at the command level.

###

###

###

Here is the complete, restructured English documentation optimized for GitBook. I have categorized the APIs into logical modules, used parameter tables, and applied GitBook's native `{% tabs %}` syntax to make the code blocks compact and easy to read.

You can copy and paste this directly into your GitBook editor.

***

## BLE API Reference

**Document Version:** V0.1 Preliminary | **Last Updated:** 2026-04-21 | **Accessible Scope:** Public

This document is intended for third-party Apps, gateways, or debugging tools to interface with the device's BLE API. It describes only the externally visible protocols and does not cover internal implementations.

### Applied Product Models

| # | Ordering Number      | Description                                     |
| - | -------------------- | ----------------------------------------------- |
| 1 | **SPM01-D2EW**       | SPM01 1PN FLEX/63A Open BLE+Wi-Fi               |
| 2 | **SPM01-D1EW**       | SPM01 1PN MCBM-BM/63A Open BLE+Wi-Fi            |
| 3 | **SPM01-U1EW**       | SPM01 1PN MCBM-TM/63A Open BLE+Wi-Fi            |
| 4 | **SPM02-D2EW**       | SPM02 3PN FLEX/63A Open BLE+Wi-Fi               |
| 5 | **SPM02-D1EW**       | SPM02 3PN MCBM-BM/63A Open BLE+Wi-Fi            |
| 6 | **SPM02-U1EW**       | SPM02 3PN MCBM-TM/63A Open BLE+Wi-Fi            |
| 7 | **SDM01-EWM-12**     | SDM01 SCTA-3×120A/Φ16 Wi-Fi (ESP32) + RS485     |
| 8 | **SDM01-EWM-20**     | SDM01 SCTA-3×200A/Φ20 Wi-Fi (ESP32) + RS485     |
| 9 | **SDM01-EWM-12-BKW** | SDM01 SCTA-3x120A/Φ16 Wi-Fi (ESP32) + RS485 BKW |

***

### 1. Connection & Interaction Overview

#### 1.1 BLE Connection Info

* **Broadcast Name Rule:** `<Product Model>-<Device Serial Number>` (e.g., `SRS01A-1234567890AB`)
* **Primary Service UUID:** `0000A002-0000-1000-8000-00805F9B34FB`
* **Write Characteristic UUID:** `0000C303-0000-1000-8000-00805F9B34FB` (Client sends commands here)
* **Notify Characteristic UUID:** `0000C305-0000-1000-8000-00805F9B34FB` (Device returns results here)
* **Read Characteristic UUID:** `0000C304-0000-1000-8000-00805F9B34FB`

> 💡 **Best Practice:** Always subscribe to the **Notify Characteristic** immediately after connection. The maximum MTU can reach up to 512. We recommend using UTF-8 encoded JSON text for all requests.

#### 1.2 Standard Interaction Flow

1. **Connect & Subscribe:** Scan, connect, and subscribe to the Notify Characteristic.
2. **Unlock Session:** Send the unlock command (`cmd=pass`). Most business commands are rejected if the device is locked.
3. **Send Commands:** After a successful unlock, subsequent commands in the same session do not need to carry the password (`pas`) or auth token (`auth`).
4. **Receive Results:** Listen to the Notify Characteristic for the `ok`, `msg`, `event`, and `d` (data) fields.

***

### 2. Authentication & Session Management

#### Initial Handshake (`pass`)

Unlocks the session, changes the password, sets session persistence, and binds the initial authentication identifier.

**Parameters:**

| Field                                                                                 | Type    | Required | Description                                                               |
| ------------------------------------------------------------------------------------- | ------- | :------: | ------------------------------------------------------------------------- |
| `cmd`                                                                                 | String  |    Yes   | Fixed as `pass`.                                                          |
| `pas`                                                                                 | String  |    Yes   | Current BLE password.                                                     |
| `newpas`                                                                              | String  |    No    | New password (Max 16 chars).                                              |
| `continue`                                                                            | Boolean |    No    | Keep session alive. If omitted, every communication requires a handshake. |
| `auth`                                                                                | String  |    No    | Authentication identifier (Max 40 chars).                                 |
| {                                                                                     |         |          |                                                                           |
| "cmd": "pass",                                                                        |         |          |                                                                           |
| "pas": "123456",                                                                      |         |          |                                                                           |
| "continue": true                                                                      |         |          |                                                                           |
| }                                                                                     |         |          |                                                                           |
| `</div><div data-gb-custom-block data-tag="tab" data-title='Response (Success)'>`json |         |          |                                                                           |
| {                                                                                     |         |          |                                                                           |
| "ok": true,                                                                           |         |          |                                                                           |
| "msg": "Password Correct",                                                            |         |          |                                                                           |
| "event": "pass"                                                                       |         |          |                                                                           |
| }                                                                                     |         |          |                                                                           |
| `</div><div data-gb-custom-block data-tag="tab" data-title='Response (Fail)'>`json    |         |          |                                                                           |
| {                                                                                     |         |          |                                                                           |
| "ok": false,                                                                          |         |          |                                                                           |
| "msg": "Password Error",                                                              |         |          |                                                                           |
| "event": "pas"                                                                        |         |          |                                                                           |
| }                                                                                     |         |          |                                                                           |
| \`\`\`### Modify BLE Password (`blepassword`)                                         |         |          |                                                                           |
| Changes the BLE connection password.                                                  |         |          |                                                                           |

**Parameters:**

| Field                                                                                                                                                                               | Type   | Required | Description                  |
| ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------ | :------: | ---------------------------- |
| `cmd`                                                                                                                                                                               | String |    Yes   | Fixed as `blepassword`.      |
| `old`                                                                                                                                                                               | String |    Yes   | Old password.                |
| `new`                                                                                                                                                                               | String |    Yes   | New password (Max 16 chars). |
| {                                                                                                                                                                                   |        |          |                              |
| "cmd": "blepassword",                                                                                                                                                               |        |          |                              |
| "old": "123456",                                                                                                                                                                    |        |          |                              |
| "new": "654321"                                                                                                                                                                     |        |          |                              |
| }                                                                                                                                                                                   |        |          |                              |
| `</div><div data-gb-custom-block data-tag="tab" data-title='Response'>`json                                                                                                         |        |          |                              |
| {                                                                                                                                                                                   |        |          |                              |
| "ok": true,                                                                                                                                                                         |        |          |                              |
| "msg": "Password yes",                                                                                                                                                              |        |          |                              |
| "event": "blepassword"                                                                                                                                                              |        |          |                              |
| }                                                                                                                                                                                   |        |          |                              |
| \`\`\`### Unbind (`resetauth`)                                                                                                                                                      |        |          |                              |
| <p>Clears the bound authentication status.</p><div data-gb-custom-block data-tag="tabs"><div data-gb-custom-block data-tag="tab" data-title="Request"><p>\`\`\`json</p></div></div> |        |          |                              |
| {                                                                                                                                                                                   |        |          |                              |
| "cmd": "resetauth"                                                                                                                                                                  |        |          |                              |
| }                                                                                                                                                                                   |        |          |                              |
| `</div><div data-gb-custom-block data-tag="tab" data-title='Response'>`json                                                                                                         |        |          |                              |
| {                                                                                                                                                                                   |        |          |                              |
| "ok": true,                                                                                                                                                                         |        |          |                              |
| "msg": "resetauth received",                                                                                                                                                        |        |          |                              |
| "event": "resetauth"                                                                                                                                                                |        |          |                              |
| }                                                                                                                                                                                   |        |          |                              |
| \`\`\`### Unlock Read Characteristic (`read`)                                                                                                                                       |        |          |                              |
| Enables the readable state to prepare for subsequent status data reading.                                                                                                           |        |          |                              |

**Parameters:**

| Field                                                                       | Type    | Required | Description                                                 |
| --------------------------------------------------------------------------- | ------- | :------: | ----------------------------------------------------------- |
| `cmd`                                                                       | String  |    Yes   | Fixed as `read`.                                            |
| `continue`                                                                  | Boolean |    No    | Default is read once. Set to `true` for continuous reading. |
| {                                                                           |         |          |                                                             |
| "cmd": "read",                                                              |         |          |                                                             |
| "continue": true                                                            |         |          |                                                             |
| }                                                                           |         |          |                                                             |
| `</div><div data-gb-custom-block data-tag="tab" data-title='Response'>`json |         |          |                                                             |
| {                                                                           |         |          |                                                             |
| "ok": true,                                                                 |         |          |                                                             |
| "msg": "ready",                                                             |         |          |                                                             |
| "event": "read"                                                             |         |          |                                                             |
| }                                                                           |         |          |                                                             |

````</div></div>---

## 3. Network & Communication Configuration

### Wi-Fi Configuration (`wifi`)
Sets the Wi-Fi connection parameters.

**Parameters:**
| Field | Type | Required | Description |
| :--- | :--- | :---: | :--- |
| `cmd` | String | Yes | Fixed as `wifi`. |
| `ssid` | String | Yes | Wi-Fi Name (Max 64 chars). |
| `pass` | String | Yes | Wi-Fi Password (Max 64 chars). |<div data-gb-custom-block data-tag="tabs"><div data-gb-custom-block data-tag="tab" data-title='Request'>```json
{
  "cmd": "wifi",
  "ssid": "OfficeWiFi",
  "pass": "12345678"
}
```</div><div data-gb-custom-block data-tag="tab" data-title='Response'>```json
{
  "ok": true,
  "msg": "WIFI successfully",
  "event": "wifi"
}
```</div></div>### MQTT Configuration (`mqtt` / `mqtr`)
Configures the MQTT broker settings.

> ⚠️ **Warning:** Using the `mqtr` command will automatically trigger a device reboot after saving.

**Parameters:**
| Field | Type | Required | Description |
| :--- | :--- | :---: | :--- |
| `cmd` | String | Yes | `mqtt` (save) or `mqtr` (save & reboot). |
| `data` | String | Yes | Format: `host|clientid|ssl|port|interval|username|password` |<div data-gb-custom-block data-tag="tabs"><div data-gb-custom-block data-tag="tab" data-title='Request'>```json
{
  "cmd": "mqtt",
  "data": "broker.example.com|dev01|1|8883|5|user|pwd"
}
```</div><div data-gb-custom-block data-tag="tab" data-title='Response'>```json
{
  "ok": true,
  "msg": "MQTT successfully",
  "event": "mqtt"
}
```</div></div>### Set MQTT Topics (`topic1` & `topic2`)
Configures uplink/downlink and response/metadata topics.

**Parameters for `topic1`:**
| Field | Type | Required | Description |
| :--- | :--- | :---: | :--- |
| `cmd` | String | Yes | Fixed as `topic1`. |
| `topic_post` | String | Yes | Uplink topic. |
| `topic_set` | String | Yes | Downlink control topic. |

**Parameters for `topic2`:**
| Field | Type | Required | Description |
| :--- | :--- | :---: | :--- |
| `cmd` | String | Yes | Fixed as `topic2`. |
| `topic_response` | String | Yes | Response topic. |
| `topic_metadata` | String | Yes | Metadata topic. |<div data-gb-custom-block data-tag="tabs"><div data-gb-custom-block data-tag="tab" data-title='Request (Topic 1)'>```json
{
  "cmd": "topic1",
  "topic_post": "dev/up",
  "topic_set": "dev/down"
}
```</div><div data-gb-custom-block data-tag="tab" data-title='Request (Topic 2)'>```json
{
  "cmd": "topic2",
  "topic_response": "dev/resp",
  "topic_metadata": "dev/meta"
}
```</div></div>### UDP Management (`udp`, `deleteudp`, `udpdata`)
Manage UDP upload targets.

**Parameters for Add/Delete:**
| Field | Type | Required | Description |
| :--- | :--- | :---: | :--- |
| `cmd` | String | Yes | `udp` (Add) or `deleteudp` (Delete). |
| `IpAddress` | String | Yes | Target IP Address. |
| `localUdpPort` | Integer| Yes | Target Port. |<div data-gb-custom-block data-tag="tabs"><div data-gb-custom-block data-tag="tab" data-title='Add Target'>```json
{
  "cmd": "udp",
  "IpAddress": "192.168.1.100",
  "localUdpPort": 9000
}
```</div><div data-gb-custom-block data-tag="tab" data-title='Delete Target'>```json
{
  "cmd": "deleteudp",
  "IpAddress": "192.168.1.100",
  "localUdpPort": 9000
}
```</div><div data-gb-custom-block data-tag="tab" data-title='List Targets'>```json
{
  "cmd": "udpdata"
}
````

// Response: { "ok": true, "event": "udpdata", "d": { "items": \[] } }---

### 4. Device Control & Status

#### Device Operations (`restart`, `reset`, `location`, `zero`)

Basic device control commands requiring only the `cmd` field.

* `restart`: Triggers device reboot.
* `reset`: Clears configuration and triggers a factory reset.
* `location`: Device indicator flashes at 4Hz for 15 seconds.
* `zero`: Clears all accumulated energy data (Irreversible).

  \### Device Name (`deviceName`) Sets a custom name for the device.

**Parameters:**

| Field                                                                                                                                                                                         | Type   | Required | Description                 |
| --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ------ | :------: | --------------------------- |
| `cmd`                                                                                                                                                                                         | String |    Yes   | Fixed as `deviceName`.      |
| `name`                                                                                                                                                                                        | String |    Yes   | Device name (Max 30 chars). |
| {                                                                                                                                                                                             |        |          |                             |
| "cmd": "deviceName",                                                                                                                                                                          |        |          |                             |
| "name": "RoomMeter01"                                                                                                                                                                         |        |          |                             |
| }                                                                                                                                                                                             |        |          |                             |
| \`\`\`### Read Configuration (`model` & `mqttdata`)                                                                                                                                           |        |          |                             |
| <p>Reads device configuration snapshots.</p><div data-gb-custom-block data-tag="tabs"><div data-gb-custom-block data-tag="tab" data-title="Read Config (model)"><p>\`\`\`json</p></div></div> |        |          |                             |
| {                                                                                                                                                                                             |        |          |                             |
| "cmd": "model",                                                                                                                                                                               |        |          |                             |
| "type": 1                                                                                                                                                                                     |        |          |                             |
| }                                                                                                                                                                                             |        |          |                             |

````
// Response:
{
  "ok": true,
  "event": "model",
  "d": { "WN": "OfficeWiFi", "MH": "broker.example.com" }
}</div><div data-gb-custom-block data-tag="tab" data-title='Read MQTT Data'>```json
{
  "cmd": "mqttdata"
}
````

// Response: { "ok": true, "event": "mqttdata", "d": { "TP": "dev/up", "TC": "dev/down" } }---

### 5. Feature Flags & Protocols

#### Function Map (`getFunctionMap` / `functionMap`)

Reads or writes the 16-bit feature bitmap.

**Bit Definition Table (Bit 15 is MSB):**

| Bit                     | Function   | Description             |
| ----------------------- | ---------- | ----------------------- |
| 15                      | Modbus TCP | `1=Enable`, `0=Disable` |
| 14                      | TLS Enable | `1=Enable`, `0=Disable` |
| 13                      | UDP        | `1=Enable`, `0=Disable` |
| 11                      | WebSocket  | `1=Enable`, `0=Disable` |
| 9                       | MQTT       | `1=Enable`, `0=Disable` |
| 7                       | HTTP       | `1=Enable`, `0=Disable` |
| 5                       | LoRaWAN    | `1=Enable`, `0=Disable` |
| {                       |            |                         |
| "cmd": "getFunctionMap" |            |                         |
| }                       |            |                         |
|                         |            |                         |

````
// Response:
{
  "ok": true,
  "event": "getFunctionMap",
  "d": { "functionMap": 37376 }
}</div><div data-gb-custom-block data-tag="tab" data-title='Write (functionMap)'>```json
{
  "cmd": "functionMap",
  "value": 37376
}
```</div></div>### Enable Services (`enable...`)
Quick toggle commands for specific services. All require `cmd` and a boolean `enable` field (except HTTP).

* `enablehttp`: Enables HTTP (No `enable` field required).
* `enablewebsocket`: Enables/Disables WebSocket.
* `enablemodbustcp`: Enables/Disables Modbus TCP.
* `enabletls`: Enables/Disables TLS.<div data-gb-custom-block data-tag="tabs"><div data-gb-custom-block data-tag="tab" data-title='Request Example'>```json
{
  "cmd": "enablewebsocket",
  "enable": true
}
```</div></div>### Modbus Parameters (`modbus`)
Sets serial Modbus communication parameters.

**Parameters:**
| Field | Type | Required | Description |
| :--- | :--- | :---: | :--- |
| `cmd` | String | Yes | Fixed as `modbus`. |
| `baud` | Integer| Yes | Baud rate (e.g., 9600). |
| `parityStop` | Integer| Yes | Parity/Stop bits configuration. |
| `address` | Integer| Yes | Slave address. |<div data-gb-custom-block data-tag="tabs"><div data-gb-custom-block data-tag="tab" data-title='Request'>```json
{
  "cmd": "modbus",
  "baud": 9600,
  "parityStop": 0,
  "address": 1
}
```</div></div>### TLS Multiplexing Status (`getModbusTlsMuxSetupStatus`)
Reads the Modbus TLS multiplexing status value.<div data-gb-custom-block data-tag="tabs"><div data-gb-custom-block data-tag="tab" data-title='Request'>```json
{
  "cmd": "getModbusTlsMuxSetupStatus"
}
```</div><div data-gb-custom-block data-tag="tab" data-title='Response'>```json
{
  "ok": true,
  "event": "getModbusTlsMuxSetupStatus",
  "d": { "modbusTlsMuxSetupStatus": 1 }
}
```</div></div>**Status Values:**
* `0`: Uninitialized.
* `1`: Started successfully in plaintext (incomplete certificates).
* `2`: TLS started successfully.
* `3`: Certificate/Key file error.
* `4`: TLS socket/bind/listen failed.
* `5`: Plaintext startup failed.

---

## 6. Certificate Management

### Write Certificate (`cafilestart` / `cafiledata`)
Creates a certificate file and writes it in fragments.

**Parameters for Start:**
| Field | Type | Required | Description |
| :--- | :--- | :---: | :--- |
| `cmd` | String | Yes | Fixed as `cafilestart`. |
| `filename` | String | Yes | Target certificate file (e.g., `/mqtt.pem`). |

**Parameters for Data Fragment:**
| Field | Type | Required | Description |
| :--- | :--- | :---: | :--- |
| `cmd` | String | Yes | Fixed as `cafiledata`. |
| `cadata` | String | Yes | Fragment string (Fixed 128 bytes, no padding for the last packet). |<div data-gb-custom-block data-tag="tabs"><div data-gb-custom-block data-tag="tab" data-title='1. Start Writing'>```json
{
  "cmd": "cafilestart",
  "filename": "/mqtt.pem"
}
```</div><div data-gb-custom-block data-tag="tab" data-title='2. Send Fragment'>```json
{
  "cmd": "cafiledata",
  "cadata": "-----BEGIN CERTIFICATE-----"
}
```</div></div>---

## 7. OTA (Over-The-Air) Updates

### OTA Management (`checkota`, `otaprogress`, `startota`)
Commands to manage firmware updates.

* `checkota`: Queries OTA status.
* `otaprogress`: Reads progress percentage.
* `startota`: Initiates the OTA task.<div data-gb-custom-block data-tag="tabs"><div data-gb-custom-block data-tag="tab" data-title='Check Status'>```json
{
  "cmd": "checkota"
}
````

// Response: { "ok": true, "event": "checkota", "d": { "otastatus": 200 } }

\`\`\`json { "cmd": "otaprogress" }

````
// Response:
{
  "ok": true,
  "event": "otaprogress",
  "d": { "otaprogress": 60 }
}</div><div data-gb-custom-block data-tag="tab" data-title='Start OTA'>```json
{
  "cmd": "startota"
}
```</div></div>

**`otastatus` Values:**
* `200`: Update package available.
* `404`: No update package available (already on the latest version).
* `-2`: OTA URL not configured.
* *Other*: HTTP/Network error codes.
````

***

### 5. Revision History

<table><thead><tr><th width="151">Version</th><th>Date</th><th>Changes</th><th>Author</th><th>Checked</th><th>Remark</th></tr></thead><tbody><tr><td>V1.0</td><td>2025-11-01</td><td>Initial release. Dedicated complete list for limited customers and users.</td><td>HX</td><td>LHL</td><td>N/A</td></tr><tr><td>V1.1 Preliminary</td><td>2026-04-14</td><td>Document maintained from Feishu/Larksuite to Gitbook</td><td>HX</td><td>LHL</td><td>N/A</td></tr></tbody></table>

\ <br>


# BLE Secured API


# Testing


# SDM01 Combo (ESP8685)

## Custom Firmware Development Guide: SDM01 Combo (ESP8685)

{% hint style="info" %}
&#x20;**Applies to:** SDM01 Combo | **Hardware Revision:** V1.0+ | **Last Updated:** 2026-04-25
{% endhint %}

> 🛑 **DANGER: LETHAL VOLTAGE & CRITICAL SAFETY WARNING**
>
> **1. Safe Flashing (No AC Required):** The 7-pin external UART port provides a `3V3` power pin. You can and **should** flash the device using only the 3.3V power from your USB-TTL adapter, with the meter **COMPLETELY DISCONNECTED from AC mains**.
>
> **2. Live-Power Debugging (AC Connected):** Debugging the device while it is connected to live AC mains exposes you to **LETHAL VOLTAGES**.
>
> * **RCD & Isolation Transformer are MANDATORY:** Your AC test bench must be protected by an **RCD/GFCI (Residual Current Device)** feeding into an **Isolation Transformer**. You must power the meter via this isolation transformer. An opto-isolated USB-to-TTL adapter *ONLY* protects your computer; it **DOES NOT** protect you from fatal electric shocks.
> * **⚠️ The "Safety Illusion" Warning:** An isolation transformer only protects against *line-to-ground* shocks. If you touch both the Live and Neutral wires on the isolated secondary side simultaneously, the transformer will treat your body as a normal load. **The primary-side RCD will NOT detect this and WILL NOT trip**, resulting in a lethal shock across your heart.
> * **The "One-Hand Rule":** Always keep one hand in your pocket or behind your back when probing live circuits. Never touch the PCBA with both hands while it is powered.
> * **Qualified Personnel Only:** Live AC debugging must ONLY be performed by certified professionals in compliance with local electrical safety regulations.
>
> ⚖️ **DISCLAIMER OF LIABILITY:** Working with AC mains is inherently dangerous. By choosing to flash, debug, or modify this device, you acknowledge and accept all associated risks. **The manufacturer assumes NO RESPONSIBILITY or LIABILITY** for any personal injury, death, equipment damage, or property loss caused by improper handling, lack of safety precautions, or unauthorized modifications.

***

### 1. Product Overview

#### 1.1 Introduction

![](https://acnmd2zc649i.feishu.cn/space/api/box/stream/download/asynccode/?code=ZDg1NzAzYTZiZTY1NzM5ZjYxZDlkZjdmZjFmM2MzY2FfT2RHMkdmSVJHbXlodldpV0d6VlFTdG9QTVZQdWNLdXRfVG9rZW46VnE1M2JSWWFRbzZUMjl4MlBDY2MydXVsbkpoXzE3NzYxNzMxMjk6MTc3NjE3NjcyOV9WNA)

The SDM01-EWM-\* is a compact 18mm-wide DIN-rail smart energy meter designed for real-time monitoring of three-phase systems or multiple single-phase branches. It features a dual-MCU architecture, separating the:

* **Wireless Communication SoC** (ESP32-8685, [WiFi Module ESP8685-WROOM-01](https://documentation.espressif.com/esp8685-wroom-01_datasheet_en.pdf))
* **Base Meter MCU** (Handles calibration, metering, and RS485 functions)

This architecture allows developers to **flash their own custom firmware on the SoC without affecting the core metering accuracy or calibration data.**

#### 1.2 Hardware Architecture

* **Wireless SoC (Master):** Handles Wi-Fi / BLE / MQTT / HTTP / Custom Logic. It communicates with the meter MCU via internal Modbus-over-UART.
* **Base Meter MCU (Slave):** Handles metering, calibration, and RS485 Modbus RTU. Stores all measurement parameters independently.
*

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FlgzlNvgrlH55G3SUzMDd%2Fimage.png?alt=media&amp;token=5e4f4050-8a4e-4fab-93d3-7807cc82eb8d" alt=""><figcaption></figcaption></figure>

***

### 2. Hardware Flashing Guide (External UART)

> 🛑 **DANGER: HIGH VOLTAGE & CRITICAL SAFETY WARNING**
>
> **1. Safe Flashing (No AC Required):** The 7-pin external UART port provides a `3V3` power pin. You can and **should** flash the device using only the 3.3V power from your USB-TTL adapter, with the meter **COMPLETELY DISCONNECTED from AC mains**.
>
> **2. Live-Power Debugging (AC Connected):** If you must debug the device while it is connected to live AC power (e.g., to verify real-time metering data), **YOU MUST USE AN ISOLATION TRANSFORMER** to power the meter, OR use a strictly **opto-isolated USB-to-TTL adapter**. Connecting a standard, non-isolated computer to a mains-powered meter creates a direct ground loop that **WILL destroy your computer's motherboard** and poses a **LETHAL electric shock hazard**!

> 💡 **Hardware Version Notice & Ordering Instruction:** Starting from May 2026, the standard production of SDM01-EWM (Open WiFi+RS485) meters is transitioning to the **External UART Flashing Version**. This version allows developers to perform UART flashing and debugging directly through the 7-pin programming holes on the enclosure, without opening the device.
>
> ⚠️ Please note that older versions featuring the **External JTAG Port** may still be circulating in the market or present in our existing inventory. **If your development specifically requires the External UART port version, please explicitly state "Require External UART Port Version" when placing your order.**

#### 2.1 Pinout Definition

The external programming port provides all necessary pins, including a 3.3V power supply, making it completely safe to flash without connecting the meter to AC mains.

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<table><thead><tr><th width="104">Number</th><th width="106">Name</th><th width="111">Type</th><th width="359">Function / Connection Guide</th></tr></thead><tbody><tr><td><strong>1</strong></td><td>NC</td><td>NC</td><td>Not Connected</td></tr><tr><td><strong>2</strong></td><td><strong>IO9</strong></td><td>I/O/T</td><td><strong>Boot Mode Selection:</strong><br>• High/Floating: Normal Operating Mode<br>• <strong>Low (GND): Burning/Flashing Mode</strong></td></tr><tr><td><strong>3</strong></td><td>GND</td><td>P</td><td>Ground</td></tr><tr><td><strong>4</strong></td><td><strong>RXD</strong></td><td>I/O/T</td><td>GPIO20, U0RXD <em>(Connect to <strong>TX</strong> of your USB-TTL adapter)</em></td></tr><tr><td><strong>5</strong></td><td><strong>TXD</strong></td><td>I/O/T</td><td>GPIO21, U0TXD <em>(Connect to <strong>RX</strong> of your USB-TTL adapter)</em></td></tr><tr><td><strong>6</strong></td><td>GND</td><td>P</td><td>Ground</td></tr><tr><td><strong>7</strong></td><td><strong>3V3</strong></td><td>P</td><td>3.3V Power Supply <em>(Connect to <strong>3V3</strong> of your USB-TTL adapter)</em></td></tr></tbody></table>

#### 2.2 How to Enter Flashing Mode (Standard Espressif Sequence)

To flash the ESP8685 SoC, you must force it into "Download Mode" using the `IO9` pin during boot.

**Step-by-step Flashing Procedure:**

1. **Disconnect AC Power:** Ensure the meter is completely disconnected from any high-voltage AC mains.
2. **Wire the Adapter:** Connect `RXD`, `TXD`, `GND`, and `3V3` from the meter to your 3.3V USB-to-TTL serial adapter.
3. **Pull IO9 to GND:** Use a jumper wire to connect **Pin 2 (IO9)** to **Pin 3 (GND)**.
4. **Power Up:** Plug your USB-TTL adapter into your computer (this supplies 3.3V to the meter). Because IO9 is grounded during power-up, the ESP8685 will boot into **Download Mode**.
5. **Flash Firmware:** Run your flashing tool (ESP-IDF, PlatformIO, or esptool).
6. **Reboot to Normal Mode:** Once flashing is complete, disconnect the USB adapter (power off), **remove the jumper between IO9 and GND**, and power it back on. The device will now boot your custom firmware.

***

### 3. Firmware Flashing Details & Partition Tables

When compiling and flashing your custom firmware, ensure your partition table matches the device's flash layout. The default configuration is designed for a **4MB Flash** (1.9MB App, 1.9MB OTA, 190KB SPIFFS).

#### 3.1 Memory Addresses

<table><thead><tr><th>Binary File</th><th width="228">Write Address</th><th>Description</th></tr></thead><tbody><tr><td><code>bootloader.bin</code></td><td><strong>0x0000</strong></td><td>ESP32 Bootloader</td></tr><tr><td><code>partitions.bin</code></td><td><strong>0x8000</strong></td><td>Partition Table</td></tr><tr><td><code>app.bin</code></td><td><strong>0x10000</strong></td><td>Your Custom Application Firmware</td></tr><tr><td><code>spiffs.bin</code></td><td><strong>0x3D0000</strong></td><td>SPIFFS File System (Optional)</td></tr></tbody></table>

#### 3.2 Generating and Flashing SPIFFS (ESP-IDF)

If your firmware requires a SPIFFS file system (e.g., for web server HTML/CSS files), you can generate and flash it using the following ESP-IDF command:

```bash
Copypython spiffsgen.py 0x20000 yourspiffs spiffs.bin
```

**Command Explanation:**

* `spiffsgen.py`: The ESP-IDF script (if not found in your PATH, replace with the actual absolute address).
* `0x20000`: Binary code size. Make sure the size you set matches the partition size you configured in your `partitions.csv`.
* `yourspiffs`: The folder address that needs to be converted. The script will convert all files in this folder into a `.bin` file, which will be automatically parsed when uploaded to the device.
* `spiffs.bin`: The address and name of the file after successful conversion.

***

### 4. Internal Modbus-over-UART Communication

Once your custom firmware is running on the ESP8685, it needs to communicate with the Base Meter MCU to read energy data. This is done via **Modbus RTU over the internal UART**.

#### 4.1 Communication Parameters

Your ESP8685 firmware should configure its UART (acting as Modbus Master) with the following default parameters to talk to the Meter MCU (Slave):

* **Baud Rate:** `19200 bps` (Default)
* **Data Bits:** `8`
* **Parity:** `None` (N81)
* **Stop Bits:** `1`
* **Default Modbus Slave Address:** `247` (0xF7)

#### 4.2 Key Modbus Registers Quick Reference

The Meter MCU exposes all measurements via standard Modbus Holding Registers (Function Code `0x03` / `0x04`). Data is stored in **FLOAT32** format (Word Order: `AB CD`).

Here is a quick cheat sheet of the most commonly used registers to get you started:

**Basic Metering Data (Read Only - 0x03/0x04):**

| Register (DEC) | Register (HEX) | Description                         | Data Type         | Unit    |
| -------------- | -------------- | ----------------------------------- | ----------------- | ------- |
| `1000`         | `0x03E8`       | Voltage A-N                         | FLOAT32 (4 bytes) | V       |
| `1006`         | `0x03EE`       | Current A                           | FLOAT32 (4 bytes) | A       |
| `1012`         | `0x03F4`       | Active power A                      | FLOAT32 (4 bytes) | kW      |
| `1030`         | `0x0406`       | Power factor A                      | FLOAT32 (4 bytes) | -1 \~ 1 |
| `1044`         | `0x0414`       | Total active power                  | FLOAT32 (4 bytes) | kW      |
| `1052`         | `0x041C`       | Frequency                           | FLOAT32 (4 bytes) | Hz      |
| `1058`         | `0x0422`       | Total Import & Export active energy | FLOAT32 (4 bytes) | kWh     |

**Device Control & Commands (Write Only - 0x06):**

| Register (DEC) | Register (HEX) | Description                    | Command Value  |
| -------------- | -------------- | ------------------------------ | -------------- |
| `10000`        | `0x2710`       | Device locating (LED blinking) | Write `0x5055` |
| `10001`        | `0x2711`       | Reset Energy Data              | Write `0x51AA` |

**Button & LED Control**

<table><thead><tr><th width="108.11114501953125">Address (DEC)</th><th width="89.77777099609375">Address (HEX)</th><th width="128">Description</th><th width="117.3333740234375">Func Code</th><th width="85.3331298828125">R/W</th><th width="92.0001220703125">Words</th><th width="255.111083984375">Value Mapping / Remarks</th></tr></thead><tbody><tr><td>62000</td><td><code>0xF230</code></td><td>LED indication control</td><td>03, 04, 06</td><td>R/W</td><td>2</td><td><code>0x0000</code> = Flashing at 0.5Hz<br><code>0x0001</code> = Solid ON<br><code>0x0002</code> = Flashing at 0.25Hz<br><code>0x0003</code> = Flashing at 2Hz<br><code>0x0004</code> = Flashing at 5Hz<br><code>0x0005</code> = Flashing at 1Hz</td></tr><tr><td>62001</td><td><code>0xF231</code></td><td>Button status</td><td>03, 04</td><td>R/W</td><td>2</td><td><code>0x0000</code> = Idle / No action<br><code>0x0055</code> = Button long-pressed (> 5 seconds). Value auto-resets to <code>0x0000</code> upon button release.</td></tr></tbody></table>

> 📚 **Full Register Map:** For the complete list of registers (including Phase B/C, Reactive Power, Apparent Power, and Manufacturer Info), please refer to the official document: [SDM01 Combo Modbus RTU API](https://app.gitbook.com/o/aiS2FTYMQgap4pTEB6BW/s/TmsWivaZjkubbVKrCezC/device-api/modbus-rtu-register-map/sdm01-comb-modbus-rtu-api).

***

### 5. Reference & Resources

#### 5.1 **Community Open-Source Reference (Tasmota)**

If you are looking for a code template, a known open-source reference is Tasmota. We provide a bundled project package that includes an SDM01 integration module contributed by a community enthusiast.

**Please note:** The core Tasmota framework remains completely unchanged; we simply added the SDM01 driver file. Although this integration is functionally operational and its usage is generally the same as other Tasmota-based smart energy meters, it has not yet been submitted to the official Tasmota repository. Furthermore, it has not undergone the rigorous reliability testing of our official factory firmware. We highly recommend using its Modbus driver primarily as a reference or template for your custom development.

**\[📥 Download Tasmota Package with SDM01 Driver (.zip)]**

* **Path example inside the package:** `platformio_tasmota/tasmota/tasmota_xnrg_energy/xnrg_34_sdm01.ino`

#### 5.2 FAQ

**Q: Will reflashing the ESP8685 affect the measurement accuracy?** No. All metrology, calibration, and measurement logic are strictly handled by the isolated base MCU.

**Q: Can I use the ESP32-C3 toolchain for the ESP8685?** Yes. The ESP8685 is essentially an ESP32-C3 die in a different package. You can safely compile your firmware using `board = esp32-c3` in PlatformIO or ESP-IDF.\
\
**Q3: Can I modify the Modbus RTU parameters (such as baud rate and parity) in the base MCU?Yes.** You can modify these parameters either by customizing the SoC firmware code or by sending specific Modbus write commands, depending on your specific implementation needs.


# Overview

> Browse by topic below, or use the search bar to find your question directly.

### **Selection & Specs**

> Help users understand hardware capabilities and version differences before purchasing or upon first receiving the product.

<table><thead><tr><th width="166">Category</th><th width="600">Question</th></tr></thead><tbody><tr><td>Quick Answer</td><td><a data-mention href="/faq/selection-and-specs#what-communication-protocols-do-your-devices-support-all-products">Selection &amp; Specs</a></td></tr><tr><td>Quick Answer</td><td><a data-mention href="/faq/selection-and-specs#what-is-the-maximum-wire-diameter-for-the-spm01-and-spm02-spm01-spm02-products">Selection &amp; Specs</a></td></tr><tr><td>Quick Answer</td><td><a data-mention href="/faq/selection-and-specs#can-i-use-third-party-cts-with-the-sdm-series-sdm-products">Selection &amp; Specs</a></td></tr><tr><td>Quick Answer</td><td><a data-mention href="/faq/selection-and-specs#what-apps-and-gateways-hubs-do-your-products-support-all-products">Selection &amp; Specs</a></td></tr><tr><td>Quick Answer</td><td><a data-mention href="/faq/selection-and-specs#which-circuit-breakers-are-compatible-with-the-spm01-02-energy-sensors-spm-products">Selection &amp; Specs</a></td></tr><tr><td>Quick Answer</td><td><a data-mention href="/faq/selection-and-specs#can-the-spm-sdm-monitor-direct-current-dc-spm-sdm-products">Selection &amp; Specs</a></td></tr><tr><td>Quick Answer</td><td><a data-mention href="/faq/selection-and-specs#can-the-spm-meters-be-flashed-with-custom-firmware-spm-products">Selection &amp; Specs</a></td></tr></tbody></table>

***

### **Use Cases / Applications**

> Help users determine whether the products are suitable for a specific application scenario, and understand how to configure them for that use case.

<table><thead><tr><th width="166">Category</th><th width="600">Question</th></tr></thead><tbody><tr><td>Quick Answer</td><td><a data-mention href="/faq/use-cases-and-applications#do-spm-and-sdm-energy-sensors-work-with-split-phase-systems-in-usa-and-canada-120v-240v-spm-sdm-prod">Use Cases &amp; Applications</a></td></tr><tr><td>Quick Answer</td><td><a data-mention href="/faq/use-cases-and-applications#does-the-spm02-flex-support-measurement-of-three-single-phase-circuits-spm02">Use Cases &amp; Applications</a></td></tr><tr><td>Quick Answer</td><td><a data-mention href="/faq/use-cases-and-applications#does-sdm01-support-solar-export-limiting-zero-export-sdm01">Use Cases &amp; Applications</a></td></tr></tbody></table>

### **Installation & Wiring**

> Answer "can I?" and "how do I wire it?" questions during physical installation (not error troubleshooting).

### **Connectivity & Integration**

> Answer questions about App, gateway, and third-party platform integration.

<table><thead><tr><th width="166">Category</th><th width="600">Question</th></tr></thead><tbody><tr><td>Quick Answer</td><td><a data-mention href="/faq/electrical#can-spm-and-sdm-energy-sensors-be-connected-to-home-assistant-spm-sdm-products">Connectivity &amp; Integration</a></td></tr><tr><td>Quick Answer</td><td><a data-mention href="/faq/electrical#what-happens-to-my-energy-data-if-the-network-connection-of-spm-sdm-is-lost-spm-sdm-products">Connectivity &amp; Integration</a></td></tr><tr><td>Quick Answer</td><td><a data-mention href="/faq/electrical#how-do-i-set-up-wi-fi-for-the-open-wi-fi-versions-all-products">Connectivity &amp; Integration</a></td></tr><tr><td>Quick Answer</td><td><a data-mention href="/faq/electrical#can-i-flash-standard-zigbee-firmware-onto-a-tuya-zigbee-device">Connectivity &amp; Integration</a></td></tr></tbody></table>

### **Data & Measurement**

> Explain where the data displayed in the App comes from, how often it refreshes, and where it is stored.

<table><thead><tr><th width="166">Category</th><th width="600">Question</th></tr></thead><tbody><tr><td>Quick Answer</td><td><a data-mention href="/faq/data-and-measurement#what-accuracy-standard-do-your-meters-follow-spm-sdm-products">Data &amp; Measurement </a></td></tr><tr><td>Quick Answer</td><td><a data-mention href="/faq/data-and-measurement#why-does-the-spm-sdm-show-lower-or-different-energy-consumption-compared-to-another-meter">Data &amp; Measurement </a></td></tr><tr><td>Quick Answer</td><td><a data-mention href="/faq/data-and-measurement#how-to-download-the-historical-data-measured-by-spm-sdm-meters-tuya-version">Data &amp; Measurement </a></td></tr><tr><td>Quick Answer</td><td><a data-mention href="/pages/sNoHoqecjxGLxcy94xcc#tuya-davidia-vs.-basic-version-whats-the-difference">/pages/sNoHoqecjxGLxcy94xcc#tuya-davidia-vs.-basic-version-whats-the-difference</a></td></tr><tr><td>Quick Answer</td><td><a data-mention href="/faq/data-and-measurement#does-spm-sdm-support-bi-directional-energy-measurement-spm-sdm-products">Data &amp; Measurement </a></td></tr><tr><td>Detailed Guide</td><td><a data-mention href="/faq/data-and-measurement/how-to-reset-tuya-smart-switches-and-smart-meters">How to Reset Tuya Smart Switches and Smart Meters</a></td></tr></tbody></table>

### **Electrical Concepts**

> Clarify common physical phenomena that are easily misunderstood, presenting them as educational knowledge points.

### Still have a question?

* 📧 Contact our support team: **<support@bituo-technik.com>**
* 🔧 Experiencing a device issue? → Go to [Troubleshooting](/troubleshooting/overview)


# Selection & Specs

> Help users understand hardware capabilities and version differences before purchasing or upon first receiving the product.

### ⚡ Quick Answers

<details>

<summary><strong>What communication protocols do your devices support?</strong> <code>[All Products]</code></summary>

We offer multiple options based on a flexible dual-chip architecture to fit different systems:

* Wi-Fi: Typically available as Open Wi-Fi (BLE + Wi-Fi with open APIs like MQTT/HTTP for integrators and DIYers) or Tuya Wi-Fi (easy use via the Smart Life app).
* Zigbee: Choose Standard Zigbee 3.0 (open integration for integrators and DIYers) or Tuya Zigbee.
* LoRaWAN: Ideal for long-range transmission in commercial buildings, factories, and infrastructure.
* Modbus RTU: For scenarios demanding maximum stability and reliability, such as industrial environments.

Please check the specific product pages to see the supported protocols for each product line.

</details>

<details>

<summary><strong>What is the maximum wire diameter for the SPM01 and SPM02?</strong>  <code>[SPM01/SPM02 Products]</code></summary>

The SPM01 and SPM02 feature a pass-through design with a Ø9.6mm hole. It can accommodate wires up to 4 AWG (or standard 16mm²), which perfectly matches its 63A maximum current rating.

</details>

<details>

<summary><strong>Can I use third-party CTs with the SDM series?</strong> <code>[SDM Products]</code></summary>

While technically possible, we **do not recommend** using third-party CTs if you require high measurement accuracy.

Every SDM meter is shipped as a complete set. The main unit and its matched CTs are factory-calibrated and tested together to guarantee **Class 1 accuracy** (compliant with IEC 61557-12). Using third-party CTs means this accuracy can no longer be guaranteed.

**⚠️ Important Safety Warning:** If you still choose to use third-party CTs, you must strictly check the CT's secondary output current. Exceeding the meter's maximum rated input will permanently damage the device. For example, the maximum CT input current for the **SDM01** is **83.3mA**.

</details>

<details>

<summary> <strong>What Apps and Gateways/Hubs do your products support?</strong> <code>[All Products</code></summary>

Compatibility depends on the specific communication connectivity of the device you choose:

<table><thead><tr><th width="172">Connectivity</th><th width="262">App</th><th>Hub / Gateway</th></tr></thead><tbody><tr><td><strong>Tuya Wi-Fi</strong></td><td>Smart Life (or any official Tuya ODM app based on the Tuya App SDK)</td><td>None required — connects directly to Tuya Cloud via Wi-Fi router</td></tr><tr><td><strong>Tuya Zigbee</strong></td><td>Smart Life (or any official Tuya ODM app based on the Tuya App SDK)</td><td>Requires a Tuya Zigbee Gateway<sup>1)</sup></td></tr><tr><td><strong>Open Wi-Fi</strong></td><td>Our BT Power Link app; BLE API is open for custom app integration. Via open local LAN and cloud APIs, theoretically any customer-specific app or platform can be integrated</td><td>None required — connects via Wi-Fi router</td></tr><tr><td><strong>Standard Zigbee 3.0</strong></td><td>Any compatible app via your chosen gateway</td><td>Any universal Zigbee hub/gateway<sup>2)</sup></td></tr><tr><td><strong>LoRaWAN</strong></td><td>Your own system or app</td><td>Any LoRaWAN Gateway + Network Server</td></tr><tr><td><strong>Modbus RTU</strong></td><td>Your integrated software system</td><td>Any Modbus Master device (e.g., PLC, RTU, Gateway)</td></tr></tbody></table>

**📝 Notes:**

1. **Tuya Zigbee + Zigbee2MQTT:** Technically possible for DIY use, but **not recommended for large-scale commercial deployments** due to stability issues (e.g., Zigbee network storms caused by how data packets by Tuya's Zigbee firmware) and potential security risks (e.g. No installation code used). For open integration, choose **Standard Zigbee 3.0** instead.
2. **Standard Zigbee 3.0 Gateways:** Please note that while there are many Zigbee gateways available for building system integrators (such as the [SMHUB Nano Hub](https://smartlight.me/smart-home-devices/zigbee-devices/smhub-nano)), many smart home hub with Zigbee gateway feature actually have limited openness for third-party device integration. We highly recommend confirming compatibility before purchase. Smart home hub we have officially verified include Home Assistant, SmartThings, and Homey.

</details>

<details>

<summary><strong>Which circuit breakers are compatible with the SPM01/02 energy sensors?</strong> <code>[SPM Products]</code></summary>

Compatibility depends on the installation variant you choose. **If you are unsure about compatibility, we highly recommend choosing the Flexible version.**

* **Flexible / "Hanging-on-cable" Version (Universal & Recommended):** Fits **all brands** of circuit breakers. It is installed by simply hanging on the phase line that passes through the sensor's hole, making it universally compatible regardless of the breaker's design.
* **"Miniature-Circuit-Breaker-Mounting" (MCBM) Version:** Requires specific matching because terminal designs and housings vary across different manufacturers.
  * **Officially Verified:** Fully verified for compatibility (wiring capacity, thermal performance, and mechanical fit) with the Siemens 5SY / 5SL series.
  * **Other Brands:** While we have seen successful user installations with models such as Eaton PL9, ABB SH200, and Hager MC, these have not been officially tested or verified by our team. Due to the vast variety of breakers on the market, we cannot officially guarantee compatibility for unverified models.

</details>

<details>

<summary><strong>Can the SPM/SDM monitor direct current (DC)?</strong> <code>[SPM/SDM Products]</code></summary>

No, both the SPM and SDM series are designed exclusively for **alternating current (AC)** monitoring and cannot measure direct current (DC).

Currently, we do not offer any DC measurement devices, and please note that there are no plans to introduce DC products in our 2026 product roadmap.

</details>

<details>

<summary><strong>Can the SPM meters be flashed with custom firmware?</strong> <code>[SPM Products]</code></summary>

Technically yes, but **only for the Open Wi-Fi and Standard Zigbee versions**. It is not possible to flash custom firmware onto the Tuya Wi-Fi or Tuya Zigbee versions.\
\
**Technical Background:** For users wondering if they can flash Standard/Open firmware onto Tuya hardware, this will not work because the internal hardware architecture and UART communication logic are completely reversed between the two variants:

* **Tuya Wi-Fi & Tuya Zigbee Versions:** The internal MCU acts as the **master**. It controls the communication SoC (System on a Chip) via UART using the Tuya SDK to handle communications.
* **Open Wi-Fi & Standard Zigbee Versions:** The communication SoC acts as the **master**. It actively reads the MCU's register addresses via UART to obtain the energy data.

Because of this fundamental difference in the master-slave relationship, simply flashing standard firmware onto Tuya connectivity hardware will not make it function.

⚠️ **Safety Warning:** We strongly advise against physical modifications or flashing custom firmware. The device contains high-voltage circuits that pose serious safety risks during modification.

</details>

### 🛠️ Detailed Guides


# Use Cases & Applications

> Help users determine whether the products are suitable for a specific application scenario, and understand how to configure them for that use case.

### ⚡ Quick Answers

<details>

<summary><strong>Do SPM and SDM energy sensors work with split-phase systems in USA and Canada (120V/240V)?</strong> <code>[SPM/SDM Products]</code></summary>

Yes! Our sensors feature a wide voltage design (100\~240V AC, 50/60Hz) making them compatible with North American split-phase systems. However, please note the following hardware specifics based on the model:

**Split-Phase Model (SDM02) :**

* SDM02 is **specifically designed** for split-phase systems. Its Wi-Fi and Zigbee models are fully compatible and works perfectly across both 120V (L1-N, L2-N) and 240V (L1-L2).

**Single-Phase Models (SPM01):**

* **SPM01 Zigbee:** Fully compatible with both 120V (L1-N, L2-N) and 240V (L1-L2).
* **SPM01 Wi-Fi:** Only works across **L1-L2 (240V)**. It cannot be used on L1-N or L2-N (120V) because the 120VAC input is insufficient for the internal power supply to convert and drive the higher-consuming Wi-Fi module.

*Note: For ODM customers, we offer specially designed SPM01 Wi-Fi models for 120V applications — please contact us for details.*

**Three-Phase Models (SPM02 & SDM01):**

* We **do not recommend** using these for multi-circuit monitoring in North American residential applications. If you must use them, please choose the **Zigbee versions** (due to their lower power consumption) and avoid the Wi-Fi versions.

</details>

<details>

<summary><strong>Does the SPM02 FLEX support measurement of three single-phase circuits?</strong> <code>[SPM02]</code></summary>

* **For 220–240V 50/60Hz systems:** Yes — you can connect the **brown, black, and gray live wires** to the **same phase line**, and the device will measure all three single-phase circuits correctly.
* **For 110–120V 50/60Hz systems:** It is **not supported** due to internal power supply limitations.

</details>

<details>

<summary><strong>Does SDM01 support solar export limiting (Zero Export) ?</strong> <code>[SDM01]</code></summary>

Yes! The **BLE + Wi-Fi + RS485** model is specifically optimized for export-limiting and energy management.

> ⚡ **Pro Tip:** For ultra-fast control (<150ms response for strict zero-export), we highly recommend the **SDM01 Gen2**.

**Integration Methods:**

* **Wi-Fi (Balcony PV & ESS):** Supports UDP, WebSocket, and Modbus TCP. Includes a one-click API switch for seamless Shelly 3EM Pro replacement.
* **RS485 (Residential PV & ESS):** In addition to its own Modbus RTU register list, the SDM01 can act as a drop-in replacement by covering the key registers of ABB B23 and Eastron SDM630.

**🤝 For Equipment Manufacturers (Inverter / EVSE / ESS):**

* **Custom Firmware:** Thanks to the dual MCU + SoC architecture, manufacturers can write their own custom SoC firmware, or simply use our standard LAN-optimized firmware.
* **Integration Support:** End-to-end compatibility ultimately depends on the host system. We offer maximum technical cooperation for manufacturers looking to natively integrate our meters.

</details>

### 🛠️ Detailed Guides


# Installation & Wiring

> Answer "can I?" and "how do I wire it?" questions during physical installation (not error troubleshooting).

### ⚡ Quick Answers

\ <br>

### 🛠️ Detailed Guides


# Connectivity & Integration

> Answer questions about App, gateway, and third-party platform integration.

### ⚡ Quick Answers

<details>

<summary><strong>Can SPM and SDM energy sensors be connected to Home Assistant?</strong> <code>[SPM/SDM Products]</code></summary>

Yes! We highly recommend integrating them via **Zigbee2MQTT (Z2M)** for the best local experience. Compatibility depends on your specific version:

* **Standard Zigbee 3.0 (U00/U01):** Fully compatible with standard local setups.
* **Tuya Zigbee (GT / Basic):** GT versions support data export. *(Note: Due to past Tuya firmware updates, if your device doesn't pair correctly at first, simply try selecting a different Z2M profile, such as the latest `Tuya SPM02V3` or a lower version).*\
  \
  👉 **Tip:** To check for the latest supported models, please visit the [Zigbee2MQTT Supported Devices page](https://www.zigbee2mqtt.io/supported-devices/) and search for the vendor (**Tuya** or **BITUO TECHNIK**) along with your product model keyword (e.g., `SPM01`, `SDM02`).

</details>

<details>

<summary><strong>Which products are compatible with Zigbee2MQTT?</strong> <code>[SPM/SDM Products]</code></summary>

We actively support Zigbee2MQTT (Z2M) integration for our smart electrical products. The tables below provide direct links to the official Z2M documentation for our main devices.\
\
💡 **Note:** All models with the `-GT` suffix (Davidia version) and all Standard Zigbee 3.0 versions support an adjustable reporting interval of **5s to 3600s**.

👉 **Tip:** If you don't see your specific model below, it might be newly added. Please visit the official [Zigbee2MQTT Supported Devices page](https://www.zigbee2mqtt.io/supported-devices/) and search for the vendor (**Tuya** or **BITUO TECHNIK**) along with your product model keyword (e.g., `SPM01`, `SDM02`).\
\
**Tuya Zigbee Versions**

<table><thead><tr><th width="384">Product Name</th><th width="154">Status</th></tr></thead><tbody><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM01.html#tuya-spm01">Tuya SPM01</a></td><td>EOL</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM01V2.html">Tuya SPM01V2</a></td><td>EOL</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM01V2.5.html">Tuya SPM01V2.5</a></td><td>EOL</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM01V1-GT.html#tuya-spm01v1-gt">Tuya SPM01V1-GT</a></td><td>Active</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM02.html#tuya-spm02">Tuya SPM02</a></td><td>EOL</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM02V2.html">Tuya SPM02V2</a></td><td>EOL</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM02V2.5.html">Tuya SPM02V2.5</a></td><td>EOL</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM02V3.html#tuya-spm02v3">Tuya SPM02V3</a></td><td>EOL</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM02V1-GT.html#tuya-spm02v1-gt">Tuya SPM02V1-GT</a></td><td>Active</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SDM01.html">Tuya SDM01</a></td><td>EOL</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SDM01V1.5.html#tuya-sdm01v1-5">Tuya SDM01V1.5</a></td><td>EOL</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SDM01V1-GT.html">Tuya SDM01V1-GT</a></td><td>Active</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SDM02V1.html#tuya-sdm02v1">Tuya SDM02V1</a></td><td>EOL</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SDM02V1-GT.html#tuya-sdm02v1-gt">Tuya SDM02V1-GT</a></td><td>Active</td></tr></tbody></table>

**Standard Zigbee Versions**

<table><thead><tr><th width="388">Product Name</th><th width="130">Status</th></tr></thead><tbody><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM01-U00.html">BITUO TECHNIK SPM01-U00</a></td><td>Active</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM01-U01.html">BITUO TECHNIK SPM01-U01</a></td><td>Active</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM01-U02.html#bituo-technik-spm01-u02">BITUO TECHNIK SPM01-U02</a></td><td>Active</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM02-U00.html#bituo-technik-spm02-u00">BITUO TECHNIK SPM02-U00</a></td><td>Active</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM02-U01.html#bituo-technik-spm02-u01">BITUO TECHNIK SPM02-U01</a></td><td>Active</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM02-U02.html">BITUO TECHNIK SPM02-U02</a></td><td>Active</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SDM01W-U01.html#bituo-technik-sdm01w-u01">BITUO TECHNIK SDM01W-U01</a></td><td>Active</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SDM01B-U01.html#bituo-technik-sdm01b-u01">BITUO TECHNIK SDM01B-U01 (Single-phase)</a></td><td>Active</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SDM02-U00.html">BITUO TECHNIK SDM02-U00</a></td><td>Active</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SDM02-U01.html#bituo-technik-sdm02-u01">BITUO TECHNIK SDM02-U01</a></td><td>Active</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SDM02-U02.html#bituo-technik-sdm02-u02">BITUO TECHNIK SDM02-U02</a></td><td>Active</td></tr></tbody></table>

</details>

<details>

<summary><strong>What happens to my energy data if the network connection of SPM/SDM is lost?</strong> <code>[SPM/SDM Products]</code></summary>

The SPM and SDM sensors continue to record cumulative energy consumption locally even when offline. **No data is lost** — once the network connection is restored, the device automatically syncs the total accumulated energy to the cloud or local system.

However, please note that if the offline period is too long, the system may not display smaller time-scale energy data correctly. For example, with the Tuya connectivity version, you may see a data spike in the Smart Life app on the time it reconnects, which simply represents the total energy consumed while the device was offline.

</details>

<details>

<summary><strong>How do I set up Wi-Fi for the Open Wi-Fi versions?</strong> <code>[All Products]</code></summary>

For all our Open Wi-Fi devices (including the SPM and SDM series), Wi-Fi provisioning is conducted **exclusively via Bluetooth Low Energy (BLE)**. To ensure data security and optimize device power consumption, we do not enable AP (Access Point) mode for network configuration.

Currently, you can configure the device using the following methods:

**1) Using the BT Powerlink App**

You can easily configure the device via Bluetooth using our official mobile app.

* **Android:** [Download on Google Play](https://play.google.com/store/apps/details?id=btpowerlink.APP)
* **iOS:** [Download on the App Store](https://apps.apple.com/us/app/bt-powerlink/id6738687359?platform=iphone)

**📱 Note for HarmonyOS Users:** Please note that HarmonyOS devices cannot currently use the Android version of the app for BLE configuration. The solution coming soon is to use a WeChat Mini Program and a Web Bluetooth (browser-based) configuration tool.

**2) Integrating with your own app**

If you prefer to configure the device through your own mobile application, please contact us for the BLE API documentation.

</details>

<details>

<summary><strong>Can I flash Standard Zigbee firmware onto a Tuya Zigbee device?</strong></summary>

Although the hardware looks similar, their internal communication architecture is completely reversed:

* **Tuya Zigbee:** The MCU is the master, controlling the Zigbee chip.
* **Standard Zigbee:** The Zigbee chip is the master, reading data from the MCU. Because of this reversed master-slave relationship, cross-flashing firmware will stop the device from functioning. Please purchase the correct version for your system.

</details>

### 🛠️ Detailed Guides


# Zigbee2MQTT Compatible Devices

我们从6.1起交付的所有Tuya ZIgbee版本产品都是GT (Davidia版本)，支持通过[Update frequency (numeric)](https://www.zigbee2mqtt.io/devices/SPM02V3.html#update-frequency-numeric)这个expose去在本地修改上报频率，最小5秒，请在购买时和nij

**⚡ SPM01 Series (Single-Phase Smart Meters)**

| Product Model               | Z2M Official Doc Link                                                                           |
| --------------------------- | ----------------------------------------------------------------------------------------------- |
| **BITUO TECHNIK SPM01-U00** | [View Documentation](https://www.zigbee2mqtt.io/devices/SPM01-U00.html)                         |
| **BITUO TECHNIK SPM01-U01** | [View Documentation](https://www.zigbee2mqtt.io/devices/SPM01-U01.html)                         |
| **BITUO TECHNIK SPM01-U02** | [View Documentation](https://www.zigbee2mqtt.io/devices/SPM01-U02.html#bituo-technik-spm01-u02) |
| Tuya SPM01                  | [View Documentation](https://www.zigbee2mqtt.io/devices/SPM01.html#tuya-spm01)                  |
| Tuya SPM01V2                | [View Documentation](https://www.zigbee2mqtt.io/devices/SPM01V2.html)                           |
| Tuya SPM01V2.5              | [View Documentation](https://www.zigbee2mqtt.io/devices/SPM01V2.5.html)                         |
| Tuya SPM01V1-GT             | [View Documentation](https://www.zigbee2mqtt.io/devices/SPM01V1-GT.html#tuya-spm01v1-gt)        |

**⚡ SPM02 Series (Three-Phase / Multi-Channel Smart Meters)**

| Product Model               | Z2M Official Doc Link                                                                           |
| --------------------------- | ----------------------------------------------------------------------------------------------- |
| **BITUO TECHNIK SPM02-U00** | [View Documentation](https://www.zigbee2mqtt.io/devices/SPM02-U00.html#bituo-technik-spm02-u00) |
| **BITUO TECHNIK SPM02-U01** | [View Documentation](https://www.zigbee2mqtt.io/devices/SPM02-U01.html#bituo-technik-spm02-u01) |
| **BITUO TECHNIK SPM02-U02** | [View Documentation](https://www.zigbee2mqtt.io/devices/SPM02-U02.html)                         |
| Tuya SPM02                  | [View Documentation](https://www.zigbee2mqtt.io/devices/SPM02.html#tuya-spm02)                  |
| Tuya SPM02V2                | [View Documentation](https://www.zigbee2mqtt.io/devices/SPM02V2.html)                           |
| Tuya SPM02V2.5              | [View Documentation](https://www.zigbee2mqtt.io/devices/SPM02V2.5.html)                         |
| Tuya SPM02V3                | [View Documentation](https://www.zigbee2mqtt.io/devices/SPM02V3.html#tuya-spm02v3)              |
| Tuya SPM02V1-GT             | [View Documentation](https://www.zigbee2mqtt.io/devices/SPM02V1-GT.html#tuya-spm02v1-gt)        |

**⚡ SDM01 Series (DIN-Rail Smart Meters)**

| Product Model                               | Z2M Official Doc Link                                                                             |
| ------------------------------------------- | ------------------------------------------------------------------------------------------------- |
| **BITUO TECHNIK SDM01W-U01**                | [View Documentation](https://www.zigbee2mqtt.io/devices/SDM01W-U01.html#bituo-technik-sdm01w-u01) |
| **BITUO TECHNIK SDM01B-U01 (Single-Phase)** | [View Documentation](https://www.zigbee2mqtt.io/devices/SDM01B-U01.html#bituo-technik-sdm01b-u01) |
| Tuya SDM01                                  | [View Documentation](https://www.zigbee2mqtt.io/devices/SDM01.html)                               |
| Tuya SDM01V1.5                              | [View Documentation](https://www.zigbee2mqtt.io/devices/SDM01V1.5.html#tuya-sdm01v1-5)            |
| Tuya SDM01V1-GT                             | [View Documentation](https://www.zigbee2mqtt.io/devices/SDM01V1-GT.html)                          |
| Zemismart SDM01-3Z1                         | [View Documentation](https://www.zigbee2mqtt.io/devices/SDM01-3Z1.html#zemismart-sdm01-3z1)       |

**⚡ SDM02 Series (DIN-Rail Smart Meters)**

| Product Model               | Z2M Official Doc Link                                                                           |
| --------------------------- | ----------------------------------------------------------------------------------------------- |
| **BITUO TECHNIK SDM02-U00** | [View Documentation](https://www.zigbee2mqtt.io/devices/SDM02-U00.html)                         |
| **BITUO TECHNIK SDM02-U01** | [View Documentation](https://www.zigbee2mqtt.io/devices/SDM02-U01.html#bituo-technik-sdm02-u01) |
| **BITUO TECHNIK SDM02-U02** | [View Documentation](https://www.zigbee2mqtt.io/devices/SDM02-U02.html#bituo-technik-sdm02-u02) |
| Tuya SDM02V1                | [View Documentation](https://www.zigbee2mqtt.io/devices/SDM02V1.html#tuya-sdm02v1)              |
| Tuya SDM02V1-GT             | [View Documentation](https://www.zigbee2mqtt.io/devices/SDM02V1-GT.html#tuya-sdm02v1-gt)        |
| Zemismart SDM02-2Z1         | [View Documentation](https://www.zigbee2mqtt.io/devices/SDM02-2Z1.html#zemismart-sdm02-2z1)     |

Model

<table><thead><tr><th width="223">Product Name</th><th width="113">Status</th><th width="200">Local Update Interval (numeric)</th></tr></thead><tbody><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM01.html#tuya-spm01">Tuya SPM01</a></td><td>EOL</td><td>150-3600s</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM01V2.html">Tuya SPM01V2</a></td><td>EOL</td><td>150-3600s</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM01V2.5.html">Tuya SPM01V2.5</a></td><td>EOL</td><td>150-3600s</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM01V1-GT.html#tuya-spm01v1-gt">Tuya SPM01V1-GT</a></td><td>Active</td><td>5s-3600s</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM02.html#tuya-spm02">Tuya SPM02</a></td><td>EOL</td><td>300s-3600s</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM02V2.html">Tuya SPM02V2</a></td><td>EOL</td><td>300s-3600s</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM02V2.5.html">Tuya SPM02V2.5</a></td><td>EOL</td><td>300s-3600s</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM02V3.html#tuya-spm02v3">Tuya SPM02V3</a></td><td>Active</td><td>5s-3600s</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM02V1-GT.html#tuya-spm02v1-gt">Tuya SPM02V1-GT</a></td><td>Active</td><td>5s-3600s</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SDM01.html">Tuya SDM01</a></td><td>EOL</td><td>5s-3600s</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SDM01V1.5.html#tuya-sdm01v1-5">Tuya SDM01V1.5</a></td><td>EOL</td><td>5s-3600s</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SDM01V1-GT.html">Tuya SDM01V1-GT</a></td><td>Active</td><td>5s-3600s</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SDM02V1.html#tuya-sdm02v1">Tuya SDM02V1</a></td><td>EOL</td><td>150-3600s</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SDM02V1-GT.html#tuya-sdm02v1-gt">Tuya SDM02V1-GT</a></td><td>Active</td><td>5s-3600s</td></tr></tbody></table>

<br>


# Data & Measurement&#x20;

> Explain where the data displayed in the App comes from, how often it refreshes, and where it is stored.

### ⚡ Quick Answers

<details>

<summary><strong>What accuracy standard do your meters follow?</strong> <code>[SPM/SDM Products]</code></summary>

Both SPM and SDM comply with [**IEC 61557-12**](https://webstore.iec.ch/publication/65510), the international standard specifically designed for **Power Metering and Monitoring Devices (PMDs)** — covering active power, reactive power, power factor, and energy measurement accuracy in a unified framework.

This is distinct from IEC 62053, which applies to traditional utility billing meters. IEC 61557-12 is more appropriate for compact, embedded monitoring devices like SPM and SDM, and is increasingly adopted across the industry for this class of product.

> 📖 For a deeper dive, the blog post "Understanding the IEC 61557-12 Standard That Makes Meter Comparisons Easier-[Part 1](https://blog.se.com/energy-management-energy-efficiency/energy-regulations/2016/10/18/understanding-iec-standard-makes-meter-comparisons-easier/) and [Part 2](https://blog.se.com/energy-management-energy-efficiency/energy-regulations/2016/10/27/understanding-iec-standard-makes-meter-comparisons-easier-part-2/)", written by [Mr Franck Gruffaz](https://blog.se.com/author/franck-gruffaz/), is a good introductory material for the standard and its applications.

</details>

<details>

<summary><strong>Why does the SPM/SDM show lower (or different) energy consumption compared to another meter?</strong></summary>

Slight discrepancies are normal. If the difference is noticeable, it is typically due to one or more of the following:

**1. CT Installation Issues (SDM Only)** Ensure each clamp CT is fully snapped shut with no debris in the core gap — even a small gap causes flux leakage and lower readings.

**2. Calibration Accuracy vs. Consumer Smart Plugs** Consumer smart plugs are typically calibrated to a much looser tolerance than IEC Class 1, with errors more pronounced at low load levels.&#x20;

**3. Limited DC Component Tolerance (vs. Modern Utility Billing Meters)** SPM uses miniature CTs; SDM uses clamp CTs — both have limited immunity to DC components in the AC waveform. Modern utility billing meters are specifically rated for DC offset handling. High-power single-phase inverter-driven loads (e.g., heat pumps, variable-frequency drives) can produce asymmetric current waveforms that cause mild CT saturation, resulting in slightly lower readings. This is a known physical limitation of this class of monitors.

**4. Low-Load / Standby Accuracy Range** If the monitored circuit runs mostly at very low standby power (average current below **Imin \~50mA**), readings may fall outside the specified accuracy range. A comparison in this range is not meaningful.

**5. Accuracy Class Differences**  SDM01 comply with Class 1 (IEC61557-12). Lower-class meters or smart pluggers (±2%\~±5%) will accumulate diverging errors over time, especially under reactive or mixed loads.

**6. Other Causes** The above covers the most common scenarios, but measurement discrepancies can sometimes stem from factors specific to your installation or load profile. If you've worked through the above and the difference remains unexplained, we're happy to investigate together — and if it points to something we can improve in the product, we'll take it seriously.

> 💡 **For a clean comparison:** Use a pure resistive load (e.g., 1000W heater) and compare **real-time Wattage**, not accumulated kWh.

</details>

<details>

<summary><strong>How to download the historical data measured by SPM/SDM Meters (Tuya Version)?</strong></summary>

Previously, exporting historical energy data from standard Tuya connectivity products required complex cloud API configurations or third-party platforms like Home Assistant.

To solve this, we have fully upgraded our Tuya connectivity product range—including both **Tuya Wi-Fi and Tuya Zigbee** versions—to the new **"Davidia" (Gongtong) firmware**.

If you are using a Davidia-version SPM/SDM meter, you can download your data directly through the Smart Life App with zero programming required:

* **One-Click Data Export:** Simply tap the download icon on the completely redesigned Historical Chart Page. Your historical bi-directional energy data will be sent directly to your email in a convenient spreadsheet format.
* **Per-Phase Data Support:** For 3-phase models, you can even export historical data for each individual phase independently, which is perfect for precise analysis.

> 📖 For a detailed UI guide and a full list of supported models featuring the data export function, please check out our [product update](https://shop.bituo-technik.com/blogs/tech-hub/product-update-energy-meters-using-tuya-wifi-module-now-support-bi-directional-data-export-email-delivery).

</details>

<details>

<summary><strong>Tuya "Davidia" vs. "Basic" Version: What's the difference?</strong></summary>

Scheduled for **May 1, 2026**, all electricity meters produced and delivered by our company using Tuya AIoT services will be upgraded to the new **'Davidia'** version.

The key differences between the Davidia version and the Basic version are as follows:

**1. New Features**

* **Data Export:** Added functionality to export historical energy data and send it directly via email in a convenient spreadsheet format (Excel/CSV).
* **Per-Phase Data Support (3-Phase Models):** Users can now export and email historical data for each individual phase independently, allowing for more precise load monitoring and analysis.

**2. Technical & UI Changes**

* **Optimized Firmware:** The Davidia version utilizes specific, upgraded communication module firmware and PIDs from Tuya.
* **User Interface:** The most noticeable difference for end-users is the App interface layout. The Davidia version features a redesigned Historical Chart Page and a brand-new Data Export Page.

**UI Comparison**

| Interface                 | Tuya "Davidia" Version                                                                                                                                                                                                                        | Tuya "Basic" Version                                                                                                                                                                                              |
| ------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| **Historical Chart Page** | <p><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2F7MRv5bixOOV6GYPH7u04%2Fimage.png?alt=media&amp;token=cf81e114-ea4b-4896-a1d4-6eff4cc59ed8" alt=""><br></p> | ![](https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FHPRHeGRhVFbgdLLVkd5e%2Fimage.png?alt=media\&token=2584a72c-8ba2-4885-aeed-4780ae4aa714) |
| **Data Export Page**      | ![](https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FLaeY39a9vghreNszVnwH%2Fimage.png?alt=media\&token=1dffbc2c-41e8-4ecd-9c44-c6d50b85898f)                             | **Not Available**                                                                                                                                                                                                 |

> 💡 **Note:** Some Davidia version units have already been sold prior to May 1, 2026. If you require the data export feature, please verify the firmware version with your vendor before purchase.

</details>

<details>

<summary><strong>Does SPM/SDM support bi-directional energy measurement?</strong> <code>[SPM/SDM Products]</code></summary>

Yes! Both our SPM and SDM series support bi-directional energy measurement. They can accurately monitor both the energy consumed from the grid and the surplus energy exported back to the grid (e.g., from solar panels).

Note: If your application requires high-speed local data transmission for real-time control—such as solar export limiting—we highly recommend choosing the SDM01 Combo Gen2 series, as its dedicated metering MCU can deliver stable power readings in under 150ms.

</details>

<details>

<summary><strong>What accuracy standard does the SDM comply with?</strong> <code>[SDM Products]</code></summary>

The SDM series comply with **IEC 61557-12**, the international standard for Power Metering and Monitoring Devices (PMD). It is classified as **PMD-II / DD / Class 1**.

* **PMD-II** means the device measures all core parameters: active power (P), reactive power (Q), apparent power (S), active energy (Ea), reactive energy (Er), frequency (f), current (I), voltage (U/V), and power factor (PF).
* **DD** means the meter and its dedicated CT are calibrated and validated as a complete system.
* **Class 1** means active power and energy are measured within ±1.0% under normal load conditions (≥ 4A at PF = 1).

> This is different from IEC 62053-21, which only covers kWh billing accuracy. IEC 61557-12 covers all measured parameters in real time.

</details>

<details>

<summary><strong>What is the difference between IEC 61557-12 and IEC 62053-21?</strong> <code>[All Products]</code></summary>

|                                             | IEC 62053-21           | IEC 61557-12                   |
| ------------------------------------------- | ---------------------- | ------------------------------ |
| Designed for                                | Utility billing meters | Power monitoring devices (PMD) |
| Covers kWh                                  | ✅                      | ✅                              |
| Covers real-time P, Q, PF, I, V             | ❌                      | ✅                              |
| Suitable for export limiting / load control | ❌                      | ✅                              |

</details>

<details>

<summary><strong>Does "Class 1" mean the the device is always accurate to ±1%?</strong> <code>[All Products]</code></summary>

IEC 61557-12 Class 1 does not guarantee ±1% accuracy under all conditions. The standard defines different uncertainty limits across different current ranges and power factor conditions — and this applies to every Class 1 PMD on the market, not just the SDM01.

The table below reproduces the relevant portion of **IEC 61557-12:2021, Table 8** — the intrinsic uncertainty limits for active power and active energy, applicable to Class 1 (C = 1) PMD/DD devices:

**Table 8 — Intrinsic Uncertainty Limits (Active Power & Energy, PMD/DD, C = 1)**

<table><thead><tr><th width="211">Current Range</th><th width="141">Power Factor</th><th>Uncertainty Formula</th><th>Limit at C = 1</th></tr></thead><tbody><tr><td><span class="math">5\%I_b \leq I &#x3C; 10\%I_b</span></td><td>1</td><td><span class="math">1.0 \times C + 0.5</span></td><td><strong>±1.5%</strong></td></tr><tr><td><span class="math">10\%I_b \leq I \leq I_{max}</span></td><td>1</td><td><span class="math">1.0 \times C</span></td><td><strong>±1.0%</strong></td></tr><tr><td><span class="math">10\%I_b \leq I &#x3C; 20\%I_b</span></td><td>0.5L / 0.8C</td><td><span class="math">1.0 \times C + 0.5</span></td><td><strong>±1.5%</strong></td></tr><tr><td><span class="math">20\%I_b \leq I \leq I_{max}</span></td><td>0.5L / 0.8C</td><td><span class="math">1.0 \times C</span></td><td><strong>±1.0%</strong></td></tr></tbody></table>

*Note: For C ≥ 1, the standard sets no requirement below* $$5%I\_b$$ *at PF = 1, and below* $$10%I\_b$$ *at non-unity PF. This is consistent across all IEC 61557-12 Class 1 devices.*

Example: Applied to the SDM01-TWM-12 ($$I\_b$$ = 20A, $$I\_{max}$$ = 120A)

| Operating Zone        | Current Range | Power Factor | Accuracy  |
| --------------------- | ------------- | ------------ | --------- |
| Light load            | 1A – 2A       | 1            | **±1.5%** |
| Normal load           | 2A – 120A     | 1            | **±1.0%** |
| Light load, reactive  | 2A – 4A       | 0.5L / 0.8C  | **±1.5%** |
| Normal load, reactive | 4A – 120A     | 0.5L / 0.8C  | **±1.0%** |

The ±1.0% zone covers the vast majority of real-world operating conditions. The ±1.5% tolerance only applies at very light loads — below 2A for this model — which represents a small fraction of typical operating time in any residential or commercial installation.

</details>

<details>

<summary><strong>Can I use a third-party CT with the SDM?</strong> <code>[SDM Products]</code></summary>

No — and this is important for maintaining the accuracy specification.

Under IEC 61557-12, accuracy is a **system property** of the meter + CT combination, not the meter alone. The CT's ratio error and phase displacement must be known and compensated in the meter's calibration.

* **SDM01 Gen1:** Must use the factory-matched CT with the same Calibration ID. Substituting any other CT invalidates the Class 1 specification.
* **SDM02:** Must use the factory-matched CT with the same Calibration ID. Substituting any other CT invalidates the Class 1 specification.
* **SDM01 Gen2:** Compatible with any CT on the Bituo approved CT list. Each approved combination has been independently type-tested as a complete system.

Using an unapproved CT may cause measurement errors that cannot be corrected by firmware.

</details>

<details>

<summary><strong>What is the difference between SDM01 Gen1 and Gen2 in terms of accuracy?</strong> <code>[SDM Products]</code></summary>

Both generations meet **IEC 61557-12 Class 1** accuracy. The difference is in how that accuracy is achieved:

|                | Gen1                                         | Gen2                                          |
| -------------- | -------------------------------------------- | --------------------------------------------- |
| Accuracy class | Class 1                                      | Class 1                                       |
| CT approach    | Factory-matched pair (unique Calibration ID) | Approved CT list (multiple compatible models) |
| CT flexibility | Fixed — must use matched CT                  | Flexible — choose from approved list          |

Gen1 is a tightly matched system ideal for fixed installations. Gen2 offers more flexibility for projects where CT aperture or current rating needs to vary.

</details>

<details>

<summary><strong>What is a PMD, and how is it different from a regular energy meter?</strong> <code>[All Products]</code></summary>

A **Power Metering and Monitoring Device (PMD)**, as defined by IEC 61557-12, measures multiple electrical parameters simultaneously in real time — including active power, reactive power, apparent power, current, voltage, power factor, frequency, and bi-directional energy.

A regular energy meter (e.g., a billing meter per IEC 62053-21) typically only accumulates kWh over time. It does not provide instantaneous power readings or reactive parameters.

PMDs are used in applications where real-time power data is needed for control decisions — such as solar export limiting, EV charge management, and home energy automation.

</details>

### 🛠️ Detailed Guides

* [How to Reset Tuya Smart Switches and Smart Meters](/faq/data-and-measurement/how-to-reset-tuya-smart-switches-and-smart-meters)  `[SRS/SPM/SDM Products]`&#x20;


# How to Reset Tuya Smart Switches and Smart Meters

{% hint style="info" %}
**Status:** Stable | **Applies to:** SRS/SPM/SDM Tuya Versions | **Updated:** 2026-08-13&#x20;
{% endhint %}

\
\
Whether you are using smart switches and meters with Tuya WiFi/Zigbee connectivity, such as Bituo Technik's SRS Smart Relay Switches and SPM/SDM Smart Energy Meters, you may occasionally need to reset the device for network pairing or clear its historical energy data.

This guide provides comprehensive steps for both scenarios.

***

### 💡 Quick Guide: Which Reset Method Should You Choose?

Before you begin, identify your goal to avoid accidentally losing your data:

* **Scenario 1: Changing Wi-Fi network or switching phones, but want to perfectly retain historical energy records.** 👉 **Choose: Reset Network Pairing Only.** (Your device will reconnect, and old data will remain intact).
* **Scenario 2: Giving the device to someone else, or wanting to start energy measurement completely from zero.** 👉 **Choose: Reset Network + Clear Data.** *(Note: For SPM/SDM Smart Meters, you MUST also clear the accumulated total energy stored in the MCU's Flash memory. See the "Crucial Technical Note" at the bottom to ensure accurate App and Cloud data display).*

***

### Part 1: Smart Relay Switches

*Applicable to Bituo Technik* [*SRS Series*](https://docs.bituo-technik.com/product-document/srs-series) *and most standard Tuya Smart Switches.*

#### Scenario A: Reset Network Pairing Only

*Result: The device enters pairing mode. The virtual Device ID remains unchanged, and the energy data stored at the Tuya Cloud remains unchanged.*

You can do this in three ways:

1. **Hardware Button:** Press and hold the "Reset Button" on the device for more than 5 seconds until the LED starts flashing.
2. **Without Reset Button (Wall Switch Method):** If the relay is installed in a wall box and the physical button is inaccessible, turn off the switch between“S”, “S1” or “S2” and “L” for 5 seconds. Then, perform 5 precise switching cycles within 5 seconds: **ON → OFF → ON → OFF → ON**. The device will enter pairing mode. *(Refer to our YouTube tutorial at 01:22-01:32 for SRS01 1PM and 02:25-02:40 for SRS01 2PM).*

{% columns %}
{% column %}
**SRS01 1PM**

{% embed url="<https://www.youtube.com/watch?v=aPDcaC5aleg>" %}
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**SRS01 2PM**

{% embed url="<https://www.youtube.com/watch?v=hoEhraUdQIY>" %}

{% endcolumn %}
{% endcolumns %}

3. **Via Smart Life APP:** (Requires device to be online) Open the app -> Go to device page -> Tap the **Edit (Pen) icon** in the top right -> Tap **Remove Device** -> Select **Remove**.

#### Scenario B: Reset Network + Clear Data

*Result: The device generates a NEW virtual Device ID upon repairing. Previous cloud data (e.g., energy consumption charts) is permanently deleted.*

* **Via Smart Life APP:** Open the app -> Go to device page -> Tap the Edit (Pen) icon -> Tap Remove Device -> Select Remove and Clear data.&#x20;

{% columns %}
{% column %}
**Go to device page**&#x20;

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FlY9EsP9vqOWneBjkHRsO%2FScreenshot_20260814_143743_com_tuya_smartlifeiot_FamilyHomeActivity.jpg?alt=media&amp;token=c9a57646-9471-4c50-be32-56dd669c8ac2" alt="" width="188"><figcaption></figcaption></figure>
{% endcolumn %}

{% column %}
Tap the **Edit (Pen) icon**&#x20;

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FYo3d6LSbeUHnTvW3WY9j%2FSRS01-2PM-Main-UI-02.jpg?alt=media&amp;token=fca2f00f-7be6-4619-964b-f082bbd15f35" alt="" width="188"><figcaption></figcaption></figure>
{% endcolumn %}

{% column width="25%" %}
Tap **Remove Device**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FJFbrD2IwMZBdcrA0crFJ%2FSRS01-2PM-Main-Device-Editing.jpg?alt=media&amp;token=6ec8b29e-8660-4553-8105-03dc9b2a9ddc" alt="" width="188"><figcaption></figcaption></figure>
{% endcolumn %}

{% column width="25%" %}
Select **Remove and Clear data**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2F4qCvAduRFz2rremWg7M4%2FSRS01-2PM-Main-Device-Editing-Reset.jpg?alt=media&amp;token=1e02bdc8-2358-4a61-84b9-c199af6d80ea" alt="" width="188"><figcaption></figcaption></figure>
{% endcolumn %}
{% endcolumns %}

<br>

{% columns %}
{% column %}
***Before Data Clearing Screenshot***

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FV9xAYM9raXf4SovLJUYu%2FSRS-Energy-Data-Before-Clearing.jpg?alt=media&amp;token=61f4c38e-5b74-4587-9563-bbb9088f0d43" alt="" width="188"><figcaption></figcaption></figure>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FhydUoiR2J4hEn3qkuoXH%2FVirtual-ID-Old_20260814_150514_com_tuya_smartlifeiot_GZLActivity.jpg?alt=media&amp;token=b6389d7b-b44e-4d09-bb77-adb44fc5a53d" alt="" width="188"><figcaption></figcaption></figure>
{% endcolumn %}

{% column %}
***After Data Clearing Screenshot***

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FRKwrupSi0nfOR0WXBmsY%2FSRS-Energy-Data-After-Clearing.jpg?alt=media&amp;token=7f958214-c4f0-4eca-b520-8724679b9906" alt="" width="188"><figcaption></figcaption></figure>

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FZ9K2fGDoPQELL6DIPKho%2FVirtual-ID-New_20260814_150417_com_tuya_smartlifeiot_GZLActivity.jpg?alt=media&amp;token=af2626f6-0f00-45b2-a6d8-67d52ce01dc3" alt="" width="188"><figcaption></figcaption></figure>
{% endcolumn %}
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***

### Part 2: Smart Meters & Circuit Breakers

*Applicable to Bituo Technik's* [*SPM Series*](https://docs.bituo-technik.com/product-document/spm-series) *and*[ *SDM Series*](https://docs.bituo-technik.com/product-document/sdm-series)*, and most Tuya Smart Meters/Circuit Breakers.*

#### Scenario A: Reset Network Pairing Only

*Result: The device enters pairing mode. The virtual Device ID remains unchanged.*

1. **Hardware Button:** Press and hold the "Reset Button" for more than 5 seconds until the LED flashes.
2. **Via Smart Life APP:** Tap the **Edit (Pen) icon** -> **Remove Device** -> **Remove**.

#### Scenario B: Reset Network + Clear Data

*Result: New virtual Device ID generated, cloud data charts are cleared.*

* **Via Smart Life APP:** Tap the **Edit (Pen) icon** -> **Remove Device** -> **Remove and Clear data**.

To ensure accurate data display after a reset, you must also clear the MCU memory:

* Go to device page in App -> **Settings** -> **Energy Management** -> **Zero Energy** -> **Confirm**.

***

### ⚠️ Crucial Technical Note: Clearing MCU Flash Accumulated Energy

Please note that the "Remove and clear data" step above **does NOT clear the total accumulated energy stored inside the device's MCU (Microcontroller Unit) Flash memory**.

**Why is this important?** Tuya handles data differently depending on the device type:

* **Smart Relays:** Report energy changes periodically (e.g., every 15 mins/1 hour). The app displays the difference.
* **Smart Meters / Circuit Breakers:** Report the **absolute total accumulated energy** to the cloud. The cloud calculates the difference between two timestamps to show your daily/monthly usage.

If you only clear the cloud data but leave the MCU data intact, your app may display incorrect energy spikes when the meter reconnects and uploads the old accumulated total.

**How to completely zero out the Meter:** To ensure accurate data display after a reset, you must also clear the MCU memory:

* Go to device page in App -> **Settings** -> **Energy Management** -> **Zero Energy** -> **Confirm**.

***

#### 🛒 Ready to Upgrade Your Energy Monitoring?

If you are looking for highly accurate, industrial-grade smart energy meters or reliable smart relays for your next project, explore our full range of professional solutions. 👉 [**Shop Bituo Technik Products Here**](https://shop.bituo-technik.com/collections/all)


# How Data Export and Historical Storage Work for SPM/SDM Sensors

{% hint style="info" %}
**Applies to:** SPM/SDM | **Updated:** 2026-08-24
{% endhint %}

**Product Design Principle** SPM and SDM series devices are engineered as **high-precision, real-time energy sensing units (Sensors)** rather than standalone Data Loggers or billing meters.

In modern IoT and energy architectures, edge gateways (running smart home OS such as Home Assistant and Homey or industrial energy management systems like Siemens Sentron Powercenter 3000) and cloud servers handle large-scale data storage far more efficiently. Therefore, The Bituo Technik real-time energy sensors store cumulative total energy locally, while high-frequency historical interval data is logged and managed by your upstream gateway or cloud platform.\
\
\
Depending on your device version and integration architecture, you can export historical data through the following channels:

***

#### 1. Tuya Wi-Fi Version

The data export capability for Tuya Wi-Fi models depends on the module firmware version integrated into your device:

* **Tuya Wi-Fi "Davidia" Firmware Version (Manufactured from April 2026 onwards):**
  * **One-Click Email Delivery:** Features a brand-new, built-in Data Export page in the Smart Life / Tuya Smart App. You can export historical bi-directional energy consumption and generation data directly to your email in CSV/spreadsheet format.
  * **Per-Phase Data Export (3-Phase Models):** For 3-phase meters (e.g., SPM02, SDM02), historical data can be exported and emailed for each individual phase independently, facilitating precise load balancing analysis.
* **Basic SoC Firmware Version (Legacy):**

  * Data is rendered on the 6 default in-app charts (hourly, daily, monthly for forward/reverse energy). Direct CSV export via the mobile app is unavailable. Users requiring raw historical data are advised to utilize the paid Tuya Cloud API or transition to our Standard Zigbee/Wi-Fi versions for local gateway integration.

{% columns %}
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<p align="center"><strong>Davidia Version</strong></p>

<p align="center"><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FRmBMS9J3uuSmhuX3Rk1o%2Fimage.png?alt=media&amp;token=556362b9-1ce5-41a2-a00a-fa866d38bca9" alt=""></p>
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<p align="center"><strong>Basic Version</strong></p>

<p align="center"><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Ff2HcjXWZKPw5QBG7UXKU%2Fimage.png?alt=media&amp;token=744a4382-4fec-4d30-a097-7ecbe7145926" alt=""></p>
{% endcolumn %}
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***

#### 2. Tuya Zigbee Version

The Tuya Zigbee models used in SPM/SDM Manufactured from July 2026 onwards are also equipped with the **Davidia firmware**, providing upgraded cloud data reporting and export capabilities when paired with Tuya infrastructure:

* **Recommended Approach (Tuya Zigbee Gateway + App Export):** We strongly recommend connecting Tuya Zigbee devices to an official Tuya Zigbee Gateway. Powered by the Davidia firmware, the Tuya Cloud supports full bi-directional energy data export and per-phase historical logging via the Smart Life App directly to your email.

{% hint style="warning" %}
**Important Note on Z2M (Zigbee2MQTT)** While integration via Z2M is technically possible, **we do not recommend using Tuya Zigbee versions with Z2M for heavy data logging**. Multi-phase meters (e.g., SPM02) transmit a high volume of Data Points (DPs). Due to the lack of native data-packet aggregation in the Tuya Zigbee protocol, frequent polling via Z2M can clog the local Zigbee mesh network and cause packet drops. For dedicated Z2M or local smart home hubs, please select our **Standard Zigbee 3.0 (-U0X)** versions.
{% endhint %}

***

#### 3. Standard Zigbee 3.0 Version (Ordering Code: `-U0X`)

Standard Zigbee 3.0 models are optimized as pure, high-speed sensing nodes for open-ecosystem integration.

* **Edge Gateway Historical Storage:** The sensor continuously pushes real-time electrical parameters to standard Zigbee coordinators (e.g., Home Assistant, Zigbee2MQTT, or open-standard edge gateways).
* **Data Export:** All historical data persistence is managed at the gateway level. For example, in Home Assistant, you can view long-term trend lines in the **History / Energy Dashboard** and export raw logs as CSV files with a single click.

***

#### 4. Standard Wi-Fi Version

Standard Wi-Fi variants feature built-in open API endpoints, including **MQTT, UDP, HTTP, and Modbus TCP**.

* **Local & Cloud Push:** You can configure your target MQTT Broker or API server directly through the device’s Embedded Web Page. The sensor streams real-time telemetry to your local gateway or cloud server.
* **Flexible Storage & Export:** The receiving gateway or server handles database logging (e.g., InfluxDB, Grafana), allowing unrestricted historical data retrieval, custom interval reporting, and CSV/Excel exports.

***

#### 5. Modbus RTU (RS485) Version

* **Industrial System Integration:** As RS485/Modbus RTU sensors, these models continuously serve real-time register data upon request.
* **Data Logging & Export:** Connect the sensor to an industrial Edge Gateway, DTU, PLC, or SCADA system. Data export is performed via the host software (e.g., Modbus Poll logging) or the central EMS platform.


# Electrical Concepts

> Clarify common physical phenomena that are easily misunderstood, presenting them as educational knowledge points.

#### ⚡ Quick Answers

<details>

<summary><strong>What does “unbalancing load” mean and what may be the causes?</strong> <code>[Three-phase Products]</code></summary>

An **unbalanced load** (or load imbalance) occurs in a multiphase electrical system when the power or current is not distributed equally among the phases.

In a perfectly balanced three-phase system, each phase carries the exact same amount of load. However, in an unbalanced situation, one or more phases carry significantly higher or lower current than the others. This imbalance can lead to system inefficiency, overheating, and potential equipment damage.

Several common factors can cause an unbalanced load:

* **Uneven Distribution of Single-Phase Loads:** If single-phase loads are connected unevenly across the three phases of a three-phase system, it can result in unbalanced loads.
* **Faulty Equipment:** Malfunctioning or faulty electrical equipment can cause an imbalance in the distribution of power among the phases.
* **Unequal Impedance:** Variations in impedance or resistance across the phases can lead to unequal distribution of power.
* **Phase-to-phase faults**: Faults or short circuits occurring between phases can cause an imbalance in the load distribution.
* **Incorrect Wiring:** Errors in the installation or wiring of electrical equipment can lead to unbalanced loads.

</details>

<br>

#### 🛠️ Detailed Guides


# Built-in RDC-DD / RCD for EV Chargers

A guide for electronic engineers and purchasers on built-in residual current protection in EV chargers, covering product selection, integration, and testing.

### ⚡ Quick Answers

<details>

<summary><strong>What is an RDC-DD?</strong> <code>[BRCS]</code></summary>

**RDC-DD** stands for **Residual Direct Current Detecting Device**. It is specifically designed for Mode 3 electric vehicle (EV) charging in compliance with the **IEC 62955** standard. Its primary function is to ensure the proper functionality of upstream Type A or Type F RCDs, even in the presence of smooth DC residual currents exceeding 6 mA.

According to IEC 62955:2018, RDC-DDs are categorized into two types:

* **RDC-MD (Residual Direct Current – Monitoring Device):** Primarily used for monitoring DC residual currents. It prevents Type A or Type F RCDs from malfunctioning (blinding) due to DC leakage above 6 mA.
* **RDC-PD (Residual Direct Current – Protection Device):** Provides comprehensive protection. In addition to handling DC residual currents above 6 mA, it also protects against AC residual currents and pulsating DC residual currents.

**The Key Difference:** The primary difference between an RDC-MD and an RDC-PD lies in their protection capabilities. While the RDC-MD effectively monitors DC leakage to protect upstream RCDs, it does *not* offer protection against AC or pulsating DC residual currents. Therefore, it is unsuitable for directly protecting human life on its own.

Because of this specific monitoring role, engineers often refer to the RDC-MD as a **DC RCM (Residual Current Monitor)**.

</details>

<details>

<summary><strong>What is the difference between an RDC-DD and a Type B RCD?</strong> <code>[BRCS]</code></summary>

The primary differences lie in how they respond to various types of residual currents, particularly smooth DC currents and high-frequency composite currents.

The table below compares the responses of **RDC-MD** (one type of RDC-DD), **RDC-PD** (the other type of RDC-DD), and **Type B RCD**:

| Residual current form                                      | RDC-MD    | RDC-PD    | Type B RCD  |
| ---------------------------------------------------------- | --------- | --------- | ----------- |
| Sinusoidal AC residual current                             | N         | Y         | Y           |
| Pulsating DC residual current                              | N         | Y         | Y           |
| Smooth DC direct currents                                  | Y (3-6mA) | Y (3-6mA) | Y (15-60mA) |
| Composite residual currents with frequencies up to 1000 Hz | N         | N         | Y           |

**Notes:**

1. **Tripping Thresholds for Smooth DC:** Type B 30mA RCDs respond to smooth DC residual currents ranging from 15mA to 60mA ($$0.5 I\_{\Delta n}$$ to $$2 I\_{\Delta n}$$, where $$I\_{\Delta n} = 30mA$$). In contrast, RDC-DD devices respond to much lower smooth DC currents, specifically between 3mA ($$0.5 I\_{\Delta dc}$$) and 6mA ($$I\_{\Delta dc}$$).
2. **High-Frequency Currents:** Composite residual currents with frequencies up to 1000 Hz are generally not found in EV charging systems where the onboard charger (OBC) is properly isolated.

</details>

<details>

<summary><strong>Why do most EV charger manufacturers prefer built-in RDC-DDs over Type B RCDs for Mode-3 charging?</strong> <code>[BRCS]</code></summary>

**A:** While some engineers assume that RDC-DDs are simply cheaper to manufacture than Type B RCDs, cost is actually not the core factor. When implemented with proper sensors, the manufacturing costs of both solutions are comparable.

The real reason RDC-DD dominates Mode-3 EVSE design is the **simplicity of electrical installation** and the prevention of a critical safety hazard known as the **DC blinding effect** in residential power grids.

Here is the technical breakdown of why the RDC-DD + Type A RCD combination is preferred:

**1. The "Blinding" Hazard in Residential Panels** In a typical home installation, an EV charger equipped with a built-in Type B RCD is usually connected to a dedicated MCB (Miniature Circuit Breaker) branch within the distribution board. If the main incoming power supply of the house uses a general Type-A or Type-AC 30mA RCBO/RCCB, a severe safety risk emerges.

If a smooth DC fault current between 6mA and 15mA occurs on the EV charger branch, the charger's Type B RCD will *not* trip (since its DC tripping threshold is 15\~60mA). Instead, this specific 6\~15mA DC current will flow back into the household grid and **"blind" the main upstream Type-A/AC RCD**. If other MCB branches—such as those for bathroom outlets or kitchen appliances—rely on this main Type-A/AC RCD for leakage protection, the blinding effect completely disables their safety mechanism, posing a hidden and lethal danger to the entire household.

**2. The Installation Hassle of Type B Solutions** To mitigate this extreme risk when using an EV charger with a Type B RCD, installers are forced to use one of two complex approaches:

* **Approach A:** Replace the main upstream household Type-A/AC RCD with an expensive Type B RCD.
* **Approach B:** Rewire the distribution board so the EV charger's power supply bypasses the main RCD (connecting its incoming power supply directly to the incoming terminal of the upstream RCD).

**3. The RDC-DD Advantage** Neither of the above approaches is ideal for residential applications due to high installation costs and inconvenience. By integrating an **RDC-DD** (which strictly trips at 6mA DC) into the EVSE, manufacturers ensure that the upstream Type A RCD is perfectly protected from DC blinding. This configuration efficiently meets **IEC 61851-1** requirements while keeping the end-user's electrical installation safe, simple, and cost-effective.

</details>

<details>

<summary><strong>Should I design a Built-in RDC-PD or an RDC-MD for my AC EV charger?</strong> <code>[BRCS]</code></summary>

**A:** While an **RDC-PD** (Protection Device) sounds ideal because it combines AC, pulsating DC, and 6mA DC detection with mechanical switching in a single unit, **we generally do not recommend attempting a built-in RDC-PD design.**

To qualify as an RDC-PD, the device must be suitable for isolation and fully comply with the stringent requirements of **IEC 61008-1** or **IEC 61009-1** (as outlined in Annex O of IEC 62955:2018). In practice, achieving this full compliance on a PCBA is extremely challenging due to the physical and electrical limitations of standard PCB-mounted power relays.

**The Practical Approach: Two Viable Alternatives** Therefore, a more accurate question is: *Should I design a built-in Type-A mRCD & RDC-MD combination, or should I opt for a built-in RDC-MD design?*

Due to varying local policies, installation habits, and power distribution setups, we recommend making this decision based on your target market:

* **Option 1: Built-in Type-A mRCD (IEC 60947-2) & RDC-MD (IEC 62955)**
  * **Commonly used in:** Markets that can accept voltage-dependent RCDs for household applications, like the UK, Nordic countries, China and India.
* **Option 2: Built-in RDC-MD (IEC 62955) Only**
  * **Commonly used in:** Markets that do not accept voltage-dependent RCDs for household applications, such as European continental countries like Germany, France, Italy and Austria.

*(💡 **Learn More:** To understand the technical differences between these two types of residual current devices, check out our detailed blog post:* [*Can Voltage-Dependent RCDs Provide Sufficient Protection?*](https://www.bituo-technik.com/can-voltage-dependent-rcds-provide-sufficient-protection/)*)*

</details>

<details>

<summary><strong>What standards should we declare for the "integrated" or "built-in" residual current protection on our EV charger's Declaration of Conformity (DoC)?</strong> <code>[BRCS]</code></summary>

For Mode-3 EVSE (AC EV Charger) manufacturers integrating our residual current sensors onto a PCBA, we highly recommend declaring conformity based on **IEC 60947-2** and **IEC 62955**.

Drawing on our expertise since the introduction of IEC 62955 in 2018, we consistently advise using one of the following declarations, depending on your hardware design:

* **Option A:** Built-in Type-A mRCD (IEC 60947-2) & RDC-MD (IEC 62955)
* **Option B:** Built-in RDC-MD (IEC 62955)

**Why avoid IEC 61008-1?** We strongly advise against declaring your built-in solution as a standard Type-A RCCB (IEC 61008-1) or RDC-PD unless your assembly strictly fulfills all their specific mechanical and electrical criteria.

Electrical safety authorities in Europe and Asia closely scrutinize EVSE compliance. Using the recommended options above accurately reflects your integrated architecture and ensures smooth market entry.

</details>

<details>

<summary><strong>Do your AC/DC residual current sensors have independent IEC 62955 RDC-DD certification and reports from an accredited independent test laboratory?</strong> <code>[BRCS]</code></summary>

Yes, for the first product in our BRCS family. However, for subsequent models, we focus on system-level compliance.

The first product in our BRCS family—the BRCS01-\*-H1—was actually the world's first residual current sensor to obtain TÜV certification back in 2019. We are happy to provide this certificate and its test report upon request.

For subsequent products in the BRCS family, we no longer conduct expensive, standalone third-party certifications for every single model. Instead, we rely on our **rigorous internal testing, combined with integration testing by our pilot customers and the successful certification of their complete charging stations**. Here is why:

* **System-Level Mandate**: According to the IEC 62955 standard, the sensor must be validated as part of a complete system. In the context of an AC EV charging station's integrated leakage protection, this "system" includes the sensor, the charging control board's power supply, the MCU, the relays, and auxiliary components on the board.
* ​**No Exemption**: A standalone component certificate cannot exempt your final product (the charging station) from system-level testing. If you review our original BRCS01-\*-H1 TÜV report, you will see it was also tested as a combination with other components.
* **Real-World Validation:** Beyond our internal tests, new products are validated through integration by our pilot customers. Their EV chargers have successfully passed complete built-in RCD / RDC-DD tests at recognized testing institutions. With years of successful application, our sensors have been widely integrated by customers across Europe and Asia.

With a well-engineered charging controller design, passing the IEC 62955 tests for a Residual Direct Current Detecting Device (RDC-DD)—**whether configured as an RDC-PD (Protection Device) or an RDC-MD (Monitoring Device)**—is straightforward. If you encounter any challenges during your integration and design process, please feel free to contact our engineering team for support.&#x20;

</details>

<details>

<summary><strong>Why do testing laboratories reject standalone IEC 62955 reports for the sensor and insist on testing it within our complete EV charging station?</strong> <code>[BRCS]</code></summary>

This is a standard industry requirement because **IEC 62955 evaluates residual direct current protection or monitoring as a complete, integrated system**, rather than an isolated component.

As mentioned, this system includes the sensor, the charging control board's power supply, the MCU, the relays, and auxiliary components on the board.

When you integrate a sensor into a new charging station, testing labs must evaluate the whole assembly because **hardware variables**—such as any changes in the PCBA layout, power supply design, or surrounding components—can significantly impact the overall function of the system (including its Electromagnetic Compatibility / EMC performance).

Therefore, reputable certification bodies (such as TÜV, DEKRA, and SGS) will not accept a sensor's historical test report that was conducted using a specific, different controller. To ensure true safety and compliance, the sensor must be tested as an integrated part of your specific, complete charging system.

</details>

<details>

<summary><strong>How to understand the 85°C maximum operating temperature?</strong> <code>[BRCS]</code></summary>

The 85°C specified in the datasheet refers to the **maximum ambient operating temperature**, not the device's surface temperature.

**Detailed Explanation:**

* **Designed for Real-World Load:** The 85°C rating already accounts for the additional temperature rise when the charger is operating under load. In actual applications, high-current traces on the PCB directly underneath the sensor can sometimes exceed 90°C.
* **Ample Redundancy:** While our sensor is designed and its components are selected to fully cover the -40°C to 105°C range, we conservatively specify 85°C as the maximum ambient temperature. This approach ensures straightforward reliability and ample redundancy under actual load conditions, avoiding the controversial "no-load" 105°C claims made by some manufacturers.
* **High Heat Resistance:** There are no concerns about the device's casing getting too hot or melting. The plastic housing of the sensor is designed to withstand temperatures up to **150°C**.

</details>

### 🛠️ Detailed Guides


# Overview

Not sure where to start? Find your symptom in the table below and jump directly to the right guide.

***

### Connectivity & Networking

| What you see                                                                   | Most likely cause                                                                   | Text                                                                                                                         |
| ------------------------------------------------------------------------------ | ----------------------------------------------------------------------------------- | ---------------------------------------------------------------------------------------------------------------------------- |
| Multiple Zigbee devices stop responding or data points go missing in dashboard | Too many devices reporting at short intervals, overwhelming the gateway             | [Zigbee Network Congestion](/troubleshooting/connectivity-and-networking/zigbee-network-congestion)                          |
| Gateway crashes or becomes unresponsive in large deployments (15+ meters)      | Zigbee bandwidth saturated by high-frequency data packets                           | [Zigbee Network Congestion](/troubleshooting/connectivity-and-networking/zigbee-network-congestion)                          |
| Device responses are noticeably delayed across the whole Zigbee network        | Inefficient data packing on Tuya Private Zigbee firmware                            | [Zigbee Network Congestion](/troubleshooting/connectivity-and-networking/zigbee-network-congestion)                          |
| Wi-Fi device goes offline every few hours and reconnects on its own            | Weak signal inside metal enclosure / router band steering forcing device off 2.4GHz | [Wi-Fi product frequently goes offline?](/troubleshooting/connectivity-and-networking/wi-fi-product-frequently-goes-offline) |
| Wi-Fi device constantly reboots or won't stay connected                        | Grid voltage too low or unstable for device operating range                         | [Wi-Fi product frequently goes offline?](/troubleshooting/connectivity-and-networking/wi-fi-product-frequently-goes-offline) |
| Device works on the bench but drops offline after installation in panel        | Metal distribution board acting as Faraday cage blocking Wi-Fi signal               | [Wi-Fi product frequently goes offline?](/troubleshooting/connectivity-and-networking/wi-fi-product-frequently-goes-offline) |
| Too many devices on the network and some randomly get kicked offline           | Router device connection limit reached                                              | [Wi-Fi product frequently goes offline?](/troubleshooting/connectivity-and-networking/wi-fi-product-frequently-goes-offline) |

***

### Wiring & Measurement

| What you see                                                                   | Most likely cause                                                                  | Go to                                                                                                                                        |
| ------------------------------------------------------------------------------ | ---------------------------------------------------------------------------------- | -------------------------------------------------------------------------------------------------------------------------------------------- |
| Power reads negative, no solar, using **SDM** series with CT clamp             | CT clamp installed in wrong direction on the wire                                  | [Wiring & Measurement](/troubleshooting/wiring-and-measurement#negative-active-power-reading)                                                |
| Power reads negative, no solar, using **SPM** series pass-through meter        | Main wire threaded through meter hole in wrong direction                           | [Wiring & Measurement](/troubleshooting/wiring-and-measurement#negative-active-power-reading)                                                |
| Power reads negative and you have solar panels                                 | Normal — solar is exporting surplus energy back to grid                            | [Wiring & Measurement](/troubleshooting/wiring-and-measurement#negative-active-power-reading)                                                |
| Displayed power is lower than V × I you calculated manually                    | Meter shows Active Power (W), not Apparent Power (VA) — Power Factor < 1.0         | [Wiring & Measurement](/troubleshooting/wiring-and-measurement#displayed-power-voltage-current)                                              |
| Heat pump circuit reads 0W or 0A even when heat pump is clearly running        | CT core magnetically saturated by DC offset injected by inverter                   | [Measurement Failure with Heat Pumps](/troubleshooting/wiring-and-measurement/measurement-failure-with-heat-pumps)                           |
| Heat pump power reading is far lower than nameplate rating                     | High-frequency harmonic interference from inverter disrupting CT and metering chip | [Measurement Failure with Heat Pumps](/troubleshooting/wiring-and-measurement/measurement-failure-with-heat-pumps)                           |
| One or more phases show large negative wattage (e.g., -500W) in 3-phase system | Voltage reference wire and current wire are on different physical phases           | [Phase Mismatch (Crossed Phases) in 3-Phase Meters](/troubleshooting/wiring-and-measurement/phase-mismatch-crossed-phases-in-3-phase-meters) |
| Power Factor reads around 50% or -50% on a standard resistive load             | Classic sign of crossed phases — voltage and current are 120° apart                | [Phase Mismatch (Crossed Phases) in 3-Phase Meters](/troubleshooting/wiring-and-measurement/phase-mismatch-crossed-phases-in-3-phase-meters) |
| One phase shows positive power while others show negative simultaneously       | CT clamped on wrong phase wire / comb busbar shifted phase sequence                | [Phase Mismatch (Crossed Phases) in 3-Phase Meters](/troubleshooting/wiring-and-measurement/phase-mismatch-crossed-phases-in-3-phase-meters) |

***

### App & Cloud

| What you see                                                                                        | Most likely cause                                                                               | Go to                                                                                                                                 |
| --------------------------------------------------------------------------------------------------- | ----------------------------------------------------------------------------------------------- | ------------------------------------------------------------------------------------------------------------------------------------- |
| Smart Life app shows "Failed to add the device" during pairing                                      | App version too old to recognize latest firmware / wrong product version (non-Tuya module)      | ["Failed to Add the Device" Error in Smart Life App](/troubleshooting/app-and-cloud/failed-to-add-the-device-error-in-smart-life-app) |
| App can find the device but pairing always times out                                                | Device has Standard Zigbee 3.0 or Open Wi-Fi module — not compatible with Smart Life            | ["Failed to Add the Device" Error in Smart Life App](/troubleshooting/app-and-cloud/failed-to-add-the-device-error-in-smart-life-app) |
| Support team asks for your device ID for remote diagnosis                                           | Need to locate Virtual ID from Smart Life app to share cloud logs                               | [Virtual ID for Tuya Connectivity Products](/troubleshooting/app-and-cloud/virtual-id-for-tuya-connectivity-products)                 |
| Device appears online in app but data never updates or refreshes                                    | Virtual ID not provided / cloud log access needed for remote diagnosis                          | [Virtual ID for Tuya Connectivity Products](/troubleshooting/app-and-cloud/virtual-id-for-tuya-connectivity-products)                 |
| Cannot set high-frequency update interval (e.g., 5s or 10s) in Zigbee2MQTT for Tuya Zigbee Products | Restrictions applied to EOL products after an accidental OTA update via the Tuya Zigbee gateway | [App & Cloud](/troubleshooting/app-and-cloud#unable-to-set-high-frequency-update-intervals-in-zigbee2mqtt-for-tuya-zigbee-products)   |

***

### &#x20;BRCS Hardware Checklist

| What you see                                          | Most likely cause                     | Go to           |
| ----------------------------------------------------- | ------------------------------------- | --------------- |
| Your issue is not listed in any of the sections above | May be a rare or model-specific issue | Contact Support |

***

### &#x20;Others

| What you see                                          | Most likely cause                     | Go to           |
| ----------------------------------------------------- | ------------------------------------- | --------------- |
| Your issue is not listed in any of the sections above | May be a rare or model-specific issue | Contact Support |

***

### 🆘 Still Stuck?

If your symptom isn't listed above, or the guide didn't resolve your issue:

* 📧 **General Support:** <support@bituo-technik.com>


# Connectivity & Networking

### ⚡Quick Fixes

### 🛠️ Detailed Guides

* [Zigbee Network Congestion](/troubleshooting/connectivity-and-networking/zigbee-network-congestion) `[All Zigbee Products]`&#x20;
* [Wi-Fi product frequently goes offline?](/troubleshooting/connectivity-and-networking/wi-fi-product-frequently-goes-offline) `[All Wi-Fi Products]`


# Zigbee Network Congestion

{% hint style="info" %}
**Applies to:** All Zigbee Connectivity Products | **Scenario:** Connectivity Issue | **Updated:** 2026-03-24
{% endhint %}

### Symptom

When deploying multiple SPM (Miniature Energy Meter) or SDM (Compact Energy Meter) devices, you may experience one or more of the following issues:

* Zigbee network congestion or "data storms"
* Dropped packets or missing data points in your dashboard
* Delayed device responses
* Gateway crashes or unresponsiveness

These symptoms typically occur in high-density setups, such as a smart home with 15+ meters in a distribution box, or a commercial electrical panel with dozens of meters.

### Cause

Network congestion in Zigbee energy monitoring systems is usually caused by the sheer volume of data being transmitted. This stems from two main factors:

1. **High-Frequency Default Reporting:** Out-of-the-box, our meters come with a fixed 30-second reporting cycle for all attributes (Voltage, Current, Power, Energy, etc.) to provide a reliable baseline. While most gateways handle this fine for a few devices, it can easily overwhelm Zigbee bandwidth as you scale up.
2. **Inefficient Data Packing (Tuya Private Zigbee):** If you are using Tuya Private Zigbee firmware, the adaptive data packing mechanism is disabled. The device sends separate data packets for each individual attribute (one for voltage, another for current, etc.), creating massive overhead.

### Resolution

To resolve network congestion and optimize your energy monitoring system, follow the steps below.

#### Step 1: Ensure you are using Standard Zigbee 3.0 Firmware

For local integrations (like Home Assistant via Z2M/ZHA) and high-density deployments, we strongly recommend using our **Standard Zigbee 3.0 models** rather than Tuya-compatible models.

* **Why?** Standard Zigbee 3.0 retains native **Attribute Batching**. It intelligently bundles multiple attributes into a single payload (or at most 2-3 optimized packets). This drastically reduces the number of radio transmissions, keeping the airwaves clean and your network rock-solid.

#### Step 2: Optimize ZCL Reporting Intervals

Standard Zigbee 3.0 firmware allows you to independently configure the update frequency for every parameter using the **ZCL Configure Reporting** command.

To reduce network load, you should adjust the **Min Interval**, **Max Interval**, and **Reportable Change (Threshold)** away from the factory defaults (30s/30s/0) based on your specific use case.

**Recommended Configuration Profiles**

Choose the profile that best matches your deployment scale:

* **Profile A: Automation & Granular Tracking (HEMS)** *Best for DIY smart homes requiring fast reactions to power changes to trigger automations (e.g., dynamic load balancing).*
* **Profile B: High-Density Pure Monitoring (BEMS / Sub-metering)** *Best for commercial buildings or branch-monitoring focusing on load profiling without choking the network.*

| Parameter        | Profile A: HEMS (Automation)                      | Profile B: BEMS (High-Density)                    | Configuration Logic & Rationale                                                                                                                                                                                                   |
| ---------------- | ------------------------------------------------- | ------------------------------------------------- | --------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------- |
| **Active Power** | <p>Min: 2s<br>Max: 900s<br>Change: 20W</p>        | <p>Min: 60s<br>Max: 300s<br>Change: 50W\~100W</p> | <p><strong>HEMS:</strong> Needs fast reporting for triggers.<br><strong>BEMS:</strong> Pure monitoring doesn't need sub-second reactions. A 60s Min and 50W threshold capture meaningful trends without spamming the network.</p> |
| **RMS Current**  | <p>Min: 3s<br>Max: 900s<br>Change: 0.1A</p>       | <p>Min: 60s<br>Max: 300s<br>Change: 0.5A</p>      | Similar to Active Power. In high-density setups, minor current fluctuations under 0.5A are treated as noise and ignored.                                                                                                          |
| **RMS Voltage**  | <p>Min: 5s<br>Max: 3600s<br>Change: 3V</p>        | <p>Min: 5s<br>Max: 3600s<br>Change: 5V</p>        | A short Min interval (5s) allows for near real-time over/under-voltage alerts. Relying on a solid threshold (3V-5V) filters out normal grid noise.                                                                                |
| **Power Factor** | <p>Min: 60s<br>Max: 3600s<br>Change: 0.05</p>     | <p>Min: 300s<br>Max: 3600s<br>Change: 0.05</p>    | <p><strong>HEMS:</strong> Rarely used for logic.<br><strong>BEMS:</strong> Crucial for power quality audits, but changes slowly. 5-minute intervals are perfect.</p>                                                              |
| **AC Frequency** | <p>Min: 300s<br>Max: 3600s<br>Change: 0.5Hz</p>   | <p>Min: 300s<br>Max: 3600s<br>Change: 0.5Hz</p>   | Grid frequency is highly stable. Set a high threshold so it only reports during severe grid anomalies, saving massive bandwidth.                                                                                                  |
| **Energy (kWh)** | <p>Min: 60s<br>Max: 3600s<br>Change: 0.01 kWh</p> | <p>Min: 300s<br>Max: 900s<br>Change: 0.1 kWh</p>  | <p><strong>HEMS:</strong> 0.01 kWh increments provide smooth daily charts.<br><strong>BEMS:</strong> 0.1 kWh thresholds with 5m/15m intervals align perfectly with 15-minute billing cycles, optimizing database storage.</p>     |

> 💡 **Key Takeaway for High-Density Installations:** For large-scale setups (like the SPM02 FLEX or SDM01 Combo installed in distribution boards), increasing the **Min interval** and **Threshold (Change)** is the ultimate key to balancing accurate energy monitoring with long-term network reliability.

<br>


# Wi-Fi product frequently goes offline?

Wi-Fi connectivity issues are typically caused by physical barriers, network settings, or electrical power factors. If your device frequently drops offline, please check the following common scenarios:

**1. Weak Signal or Metal Enclosure Interference**

* **Cause:** If the sensor is installed inside a fully metal distribution board, or separated from the router by thick concrete walls, the Wi-Fi signal will be significantly weakened (acting as a Faraday cage).
* **Solution:** Plug a Wi-Fi repeater/extender into an outlet as close to the distribution board as possible. Alternatively, consider using a distribution board with a plastic front cover/door, which allows Wi-Fi signals to pass through while keeping the metal back box compliant with local regulations.

**2. "Band Steering" & 2.4GHz Compatibility**

* **Cause:** Modern routers often use "Band Steering" (combining 2.4GHz and 5GHz under one Wi-Fi name). To optimize overall network speed, the router's logic will actively disconnect devices from the 2.4GHz band to force them onto the faster 5GHz band. Since the smart meter only has a 2.4GHz chip, it cannot connect to 5GHz and simply drops offline.
* **Solution:** Log into your router settings and separate the 2.4GHz and 5GHz networks into two different names (SSIDs), or create a dedicated 2.4GHz "Guest Network" specifically for your smart home devices.

**3. Router Device Limit (Overcrowded Network)**

* **Cause:** Standard home routers have a limit on how many devices can connect simultaneously. When overloaded, the router may temporarily kick devices offline to free up bandwidth.
* **Solution:** Disconnect a few inactive Wi-Fi devices to see if stability improves, or consider upgrading your router/adding a dedicated Access Point.

**4. Incorrect Voltage System (Mismatched Grid)**

* **Cause:** Installing the device on an incompatible power grid. For example, using an IEC 220-240V rated product on a 120V system (such as a single leg of a North American Split-Phase system). The 120V supply is far below the required operating voltage, causing the Wi-Fi module to fail or constantly reboot.
* **Solution:** Verify your local grid type before installation. Ensure the device is connected to the correct voltage (e.g., connecting across L1 and L2 for 240V in a split-phase system, or using a specific 120V version of the product).

**5. Grid Voltage Fluctuations**

* **Cause:** The device may reboot or drop offline if the local grid voltage fluctuates beyond its standard operating range (85% to 110% of the rated voltage).
* **Solution:** Ensure your local grid voltage is stable. For example, the IEC version of the SPM01 Wi-Fi is rated for 220V–240V. It requires a stable voltage between 187V and 264V (220V × 0.85 to 240V × 1.1). Extreme voltage drops or surges will cause the device to power cycle and lose connection.

**💡 Pro Tip: Assign a Static IP** To prevent IP conflicts (which can also cause offline issues when your router reassigns IP addresses after a power outage), we highly recommend logging into your router and assigning a **Static IP (DHCP Reservation)** to the sensor.


# Smart Life Failed to Add Device During Pairing

## Smart Life Failed to Add Device During Pairing

If Smart Life or Tuya Smart displays **“Failed to Add Device”** while pairing a Bituo Technik smart energy meters- such as SPM01 and SPM02, first confirm that you have the correct product version, electrical system, and connection method.

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FUImBV1es1FRrQtVT2MFT%2Fimage.png?alt=media&amp;token=4d76c59d-03ef-4cab-984b-d8d0982044c3" alt="" width="353"><figcaption></figcaption></figure>

{% hint style="warning" %}

### Important: SPM01/02 Voltage Compatibility

* **SPM01** is designed for **220–240 VAC single-phase systems**.
* **SPM02** is designed for **220–240 VAC (L–N)** or **380–415 VAC (L–L) three-phase systems**.

**SPM01 and SPM02 are not designed, rated, or supported for 120 VAC systems**, including 120/240 VAC split-phase installations.

A device powering on or appearing in an app does not confirm that it is suitable or supported for a 120 V system. Always use a meter rated for the installation voltage and wiring configuration.
{% endhint %}

### 1. Confirm the Communication Version

Bituo meters are available with different communication options. Make sure you are using the correct setup method for your device.

| Version    | Connection method                                                                                           |
| ---------- | ----------------------------------------------------------------------------------------------------------- |
| **Wi-Fi**  | Add the device in Smart Life or Tuya Smart using a 2.4 GHz Wi-Fi network.                                   |
| **Zigbee** | Add the device through a compatible Tuya Zigbee gateway. It does not connect directly to your Wi-Fi router. |

### 2. For Wi-Fi Models: Check the 2.4 GHz Network

Most Tuya Wi-Fi devices support **2.4 GHz Wi-Fi only**. They cannot join a 5 GHz-only network.

If Smart Life fails to add the device:

* Connect your phone to a 2.4 GHz Wi-Fi network.
* If your router combines 2.4 GHz and 5 GHz under one network name, temporarily separate the bands or disable band steering during setup.
* Move closer to the router or access point.
* Use a visible Wi-Fi network with WPA2-Personal or WPA2/WPA3 mixed security where possible.
* Avoid enterprise Wi-Fi, captive portals, hidden SSIDs, client isolation, and WPA3-only networks during pairing.

{% hint style="info" %}
These Wi-Fi checks apply only to Wi-Fi versions. Zigbee, BLE, and Modbus RTU / RS485 versions use different connection methods.
{% endhint %}

### 3. Reset the Meter and Check App Permissions

Reset the device according to its product manual before pairing. Switching the power off and on does not always place the device in pairing mode.

Also check that Smart Life or Tuya Smart is updated and has the permissions it requests, including:

* Bluetooth
* Nearby Devices
* Location
* Local Network

If the app is not finding the device, temporarily disable VPN or private DNS services that may interfere with local network setup.

### 4. Check Signal Strength at the Installation Location

SPM meters are often installed inside electrical distribution boards. Metal enclosures, concrete walls, and dense wiring can weaken Wi-Fi, Bluetooth, and Zigbee signals.

Try the following:

* Open the electrical panel door during pairing.
* Move the router, access point, or temporary hotspot closer to the panel.
* Complete setup before closing the enclosure.
* Check wireless coverage at the final installation location.

### 5. Try AP Mode Only If It Is Supported

AP Mode, also called Compatibility Mode, is a fallback method for some Tuya Wi-Fi devices. It is not the default pairing method for every device.

Try AP Mode only if it is listed in the product manual or shown in Smart Life / Tuya Smart for your selected device category. Follow the device-specific reset and indicator instructions.

### Still Cannot Add the Device?

Restart your phone, router, and meter, then reset the meter and try again near the router.

When contacting Bituo technical support, please provide:

* Product model and communication version
* Installation voltage and wiring configuration
* Smart Life or Tuya Smart app version
* Phone model and operating system
* Router or gateway model
* Screenshot of the error message
* The setup step where pairing fails

For specifications and product documentation, visit the [Bituo product documentation center](https://docs.bituo-technik.com/product-document/overview).


# Wiring & Measurement

### ⚡Quick Fixes

<details>

<summary><strong>Negative Active Power Reading</strong></summary>

A negative active power value indicates that energy is flowing in the reverse direction. This can be a normal operating state or an installation error. Please check the following scenarios based on your setup:

**1. Solar PV Export (Normal Operation)**

* **Cause:** If you have a solar panel or wind generation system, a negative value simply means your system is generating more power than your home is consuming, and the surplus energy is being exported back to the grid.
* **Solution:** No action required. This is normal behavior for bi-directional energy measurement.

**2. SDM Series: CT Clamp Reversed**

* **Cause:** For meters using external split-core Current Transformers (SDM series), the CT clamp is installed backward on the wire.
* **Solution:** Check the directional arrow printed on the CT clamp. The arrow **must point towards the load** (the appliance consuming power). Unclip and reverse the CT direction if necessary.

**3. SPM Series: Wire Threaded Backward**

* **Cause:** The SPM series features a pass-through (solid-core) design. If the main wire is threaded through the meter's Ø9.6mm hole in the wrong direction, the reading will be reversed.
* **Solution:** Check the directional arrow printed on the SPM device casing. Turn off the main breaker, disconnect the wire, and either **flip the device** or **thread the wire through from the opposite side** so that the actual current flow aligns with the arrow.

**4. Phase Mismatch (Multi-Phase Systems)**

* **Cause:** If you are measuring a 3-phase or split-phase system, the current sensor (CT or SPM device) might be installed on a different phase than its corresponding voltage reference (e.g., measuring the Phase B wire while powered by the Phase A voltage terminal). This phase angle mismatch will result in incorrect, often negative, power readings.
* **Solution:** Double-check your wiring map. Strictly ensure that the current measurement aligns with the correct voltage source (L1 to L1, L2 to L2, etc.).

</details>

<details>

<summary><strong>Displayed Power ≠ Voltage × Current</strong></summary>

**Cause:** The value you manually calculated ($$V \times I$$) is **Apparent Power (VA)**. However, the meter and the app display the actual **Active Power (W)**.

**Explanation:** Active Power takes the appliance's efficiency into account using the Power Factor (PF): $$Active\ Power = V \times I \times PF$$

For most household appliances (e.g., AC units, LED drivers), the Power Factor is less than 1.0. Because of this, the actual Active Power will always be lower than simply multiplying Voltage by Current.

**Note on SPM Tuya Version:** The Tuya app interface does not display the Power Factor (PF) value, which often causes this manual calculation mismatch. Rest assured, the meter's internal chip automatically includes the PF in its calculations, ensuring the displayed Active Power is 100% accurate.

</details>

### 🛠️ Detailed Guides

* [Measurement Failure with Heat Pumps](/troubleshooting/wiring-and-measurement/measurement-failure-with-heat-pumps)  `[SPM/SDM Products]`&#x20;
* [Phase Mismatch (Crossed Phases) in 3-Phase Meters](/troubleshooting/wiring-and-measurement/phase-mismatch-crossed-phases-in-3-phase-meters)   `[SPM/SDM Products]` <br>


# Measurement Failure with Heat Pumps

{% hint style="info" %}
**Applies to:** All Products with CT Clamps | **Scenario:** Heat Pump Monitoring | **Updated:** 2026-04-29
{% endhint %}

***

### 1. Overview & Symptoms

In the global market, some users may experience abnormal or completely lost readings when using standard split-core current transformers (CTs) to measure certain high-end central inverter heat pumps or single-phase inverter devices.

**Typical Symptoms:**

* **Symptom 1:** The meter reading is completely stuck at 0A / 0W, failing to capture the actual power consumption of the heat pump.
* **Symptom 2:** The reading is significantly lower than the expected power consumption based on the device's nameplate or typical operating status.

> ⚠️ **Important Note:** Cross-validation has proven that these CTs read perfectly accurately when measuring pure resistive or standard AC loads, and there are no wiring or phase sequence errors. **This is not a software bug or a quality defect of the meter.** Rather, it is a physical sensor compatibility issue caused by the extreme non-linear electrical characteristics of certain inverters affecting standard split-core CTs.

### 2. Root Cause Analysis

The complex AC-DC-AC rectification process inside inverter heat pumps causes severe distortion to the grid waveform, posing a massive challenge to standard metering equipment from the physical layer to the algorithm layer.

#### 2.1 Physical Layer: Magnetic Saturation (The Root Cause)

During operation, inverters inject a non-negligible DC offset current back into the grid. The iron core of a standard split-core CT is extremely sensitive to direct current. When superimposed with DC, the operating point of the CT core is forced into the saturation region. Once deeply saturated, the CT almost completely loses its ability to induce alternating current, **causing the secondary signal output to approach zero, making it impossible for the metering chip to sample effectively.**

#### 2.2 Algorithm Layer: High-Frequency Harmonic Interference

Severe high-frequency ringing generated by the inverter causes numerous false zero-crossings in the current waveform. This causes the Phase-Locked Loop (PLL) inside the metering chip to unlock, leading to severe deviations in Power Factor (PF) calculations.

#### 2.3 Logic Layer: The "Anti-Creep" Mechanism

Because the CT core is deeply saturated, the fragmented signal transmitted to the metering chip is extremely weak. The internal "Anti-Creep" mechanism of the chip will judge this weak signal as "background noise" and forcibly clear the registers to zero. This is why the dedicated heat pump circuit displays a perfect 0W / 0A.

### 3. Regional Market Differences

The manifestation of this physical phenomenon varies significantly across different global grid environments.

* **North American Market (High Incidence):** North American homes primarily use 120V/240V split-phase power. The DC offset and harmonics injected by high-power single-phase inverters are usually extremely severe, easily causing instant deep saturation of the CT (e.g., Lennox inverter heat pump cases).
* **European Market (Generally Good, Locally Limited):**
  * **Mitigating Factors:** European homes widely utilize 400V 3-phase connections. The symmetrical rectification architecture of 3-phase inverters naturally cancels out a large portion of the DC offset. Furthermore, strict European EMC standards (such as EN 61000-3-2) force mainstream heat pumps to be equipped with high-quality filtering circuits, drastically reducing grid pollution.
  * **Specific Trigger Scenarios:** Standard split-core CTs may still encounter measurement challenges in specific scenarios, such as **single-phase inverter devices**, **low-frequency/standby operation** (where waveform distortion peaks), or with **older/cheaper devices** where internal filtering circuits are less effective.

### 4. Issue Confirmation Steps

If you encounter a suspected 0W phenomenon caused by an inverter on-site, you can confirm it through the following simple cross-validation:

1. **Resistive Circuit Test:** Remove the CT from the heat pump circuit and clamp it onto a known circuit consisting primarily of pure resistive loads (such as an electric water heater, electric oven, or traditional incandescent lighting).
2. **Conclusion:** If the meter can immediately and accurately measure the power of this resistive circuit, it confirms that the meter and CT hardware are perfectly intact. The current 0W/low reading phenomenon is definitively a magnetic saturation failure caused by the inverter's DC offset.

### 5. Temporary Workarounds

Faced with such extreme non-linear loads, standard split-core CTs have reached their physical measurement limits. At this stage, we recommend the following on-site adjustment to restore system-level measurement:

#### Move the Measurement Point Upstream (Diluting the DC Offset)

* **Action:** Instruct the installer or electrician **not to clamp the CT solely on the dedicated, independent circuit of the inverter heat pump.** Instead, move the CT to an upstream main bus or a mixed branch circuit that includes other pure AC loads (such as whole-house lighting, standard sockets, etc.).
* **Physical Principle:** The normal alternating current generated by other pure AC loads will "dilute" the overall ratio of the DC offset in that circuit, helping the CT core retreat from the "deep saturation" state.
* **Limitation:** It is no longer possible to independently monitor the energy consumption of the heat pump, and the overall measurement accuracy of the mixed circuit may fluctuate slightly. However, it effectively prevents the entire energy management system's control logic from failing due to a 0W reading.

**Workaround Expectation Management Table:**

| Solution                                 | Applicable Scenario                 | Impact on Accuracy & Functionality                                   | Operation Difficulty                            |
| ---------------------------------------- | ----------------------------------- | -------------------------------------------------------------------- | ----------------------------------------------- |
| **Move CT to an upstream mixed circuit** | Immediate on-site mitigation        | Cannot measure HP independently; main bus accuracy slightly affected | Low (Electrician rewiring on-site)              |
| **Wait for next-gen DC-Tolerant CTs**    | Long-term precise measurement needs | Restores 100% independent and high-precision metering                | None (Requires waiting for new product release) |

### 6. Hardware Roadmap

We recognize the limitations of current industry-standard split-core CTs under extreme inverter loads. To meet users' demands for precise measurement of complex loads like high-end heat pumps and PV inverters, our hardware R\&D team is actively evaluating and developing **DC-Tolerant sensor solutions**.

While ensuring compatibility with the compact space of European domestic distribution boxes, we will introduce new transformer accessories with a much higher threshold against DC saturation in the future.

> 💡 **Need precise metering for these loads?** If you or your customers have precise metering requirements for such special loads, please contact your dedicated sales representative or technical support team to register a ticket. We will notify you immediately before these DC-tolerant accessories are launched.

In the meantime, please avoid using standard split-core CTs for independent metering on dedicated circuits of high-end inverter heat pumps. Thank you for your understanding and support.


# Phase Mismatch (Crossed Phases) in 3-Phase Meters

{% hint style="info" %}
**Applies to:** All 3-Phase Meters  | **Scenario:** Installation | **Updated:** 2026-04-25
{% endhint %}

***

### 1. Overview & Symptoms

When installing a 3-phase meter or Current Transformers (CTs), one of the most common installation errors is a **Phase Mismatch** (also known as Crossed Phases). This occurs when the voltage reference phase does not match the current measurement phase.

**Typical Symptoms:**

* **Negative Active Power:** The meter displays large negative wattage (e.g., -500W) on one or more phases, even when the system is consuming power (importing), not generating it.
* **Abnormal Power Factor (PF):** The PF drops to around 50% (0.5) or -50% (-0.5) for standard household appliances.
* **Mixed Readings:** One phase shows positive power, while the others show negative power simultaneously.

### 2. Root Cause Analysis

For a meter to calculate power correctly, the voltage reference wire (e.g., Va) and the current wire passing through the corresponding CT or meter hole (e.g., Ia) **must belong to the exact same physical phase (L1)**.

A mismatch typically occurs due to one of the following reasons:

1. **CT Installation Error:** The CT labeled "Phase A" was accidentally clamped onto the L2 or L3 physical wire.
2. **Terminal Wiring Error:** The installer manually crossed the small voltage reference wires (Va/Vb/Vc) at the meter's terminals.
3. **Comb Busbar Shifts (Common in Europe):** While some regions (like Asia) commonly use jumper wires, European markets frequently use comb busbars at the breakers. This can easily shift the physical L1-L2-L3 sequence. For example, the first slot of a new breaker might actually be sitting on L2 or L3 of the busbar.
4. **Junction Box Inconsistency:** The phase sequence inside a 3-phase appliance's plug or junction box does not match the sequence at the main distribution board.

***

### 3. Diagnosis Methods

Here are 4 methods to confirm a phase mismatch, ranked from the easiest remote check to the definitive physical test.

#### Method 1: The Power Factor (PF) Math Check (Remote / Software)

*Best for: Remote technical support analyzing data via an App or Portal.*

1. Turn off complex appliances (motors, ACs, computers) on the suspected circuit.
2. Turn on a **purely resistive load** on one phase *(e.g., plug an electric kettle into a single-phase wall socket on the suspected circuit)*.
3. **Check the Data:**
   * ✅ **Correct:** The PF should be very close to **100% (1.0)**, and the active power should be positive.
   * ❌ **Mismatched:** If the PF shows around **-50% (-0.5)** or **50% (0.5)**, it is a textbook phase mismatch.
   * **The Math Behind It:** In a 3-phase system, phases are separated by 120 degrees. If the voltage and current are from different phases, the angle between them becomes 120° (or 240°). Since $$\cos(120^\circ) = -0.5$$, the calculated Power Factor will mathematically be forced to -50%.

#### Method 2: The Single-Phase Isolation Test (User-Friendly)

*Best for: End-users who can safely flip breakers without opening the panel.*

1. Turn off 2 out of the 3 breakers for the 3-phase load (e.g., turn off L2 and L3, keeping only L1 on).
2. Turn on an appliance to draw current.
3. **Check the Data:**
   * ✅ **Correct:** The meter should show Voltage on Phase A (Va), and Current/Power **only on Phase A (Ia)**.
   * ❌ **Mismatched:** If the meter shows Voltage on Phase A, but the Current/Power appears on **Phase B or Phase C**, the wires passing through the CT holes are completely misaligned with the voltage references.

#### Method 3: The Multimeter Voltage Difference Test (Definitive)

*Best for: On-site electricians for 100% physical confirmation.*

> 🛑 **DANGER / HIGH VOLTAGE:** This test involves working inside an energized distribution panel. It must ONLY be performed by a **qualified electrician** equipped with appropriate Personal Protective Equipment (PPE). Never touch bare conductors directly.

1. Set a multimeter to AC Voltage mode (above 400V).
2. Place one probe on the meter's voltage reference terminal (e.g., `Va`).
3. Place the other probe on the exposed metal of the actual thick wire passing through Hole 1 / CT A (e.g., the screw of its breaker).
4. **Check the Reading:**
   * ✅ **Correct (Same Phase):** The multimeter reads **\~0V** (No potential difference between the same phase).
   * ❌ **Mismatched (Different Phases):** The multimeter reads a high voltage. This confirms the mismatch.
     * *\~400V* in European/Asian 3-phase systems.
     * *\~208V* in North American 3-phase WYE systems (commercial). For other configurations (e.g., 480V or 240V Delta), consult local electrical standards.

#### Method 4: Visual Wire Tracing

*Best for: Simple distribution boxes with clear, uncrowded wiring. (Note: In complex panels, this method is highly error-prone. Please use Method 3 instead).*

1. Gently tug the small wire connected to the meter's `Va` terminal and trace it back to its source breaker (e.g., L1).
2. Trace the thick main wire coming from that exact same breaker (L1).
3. **Check:** Does this thick wire pass through the 1st hole of the meter (or CT A)? If it passes through Hole 2 or 3 instead, the phases are crossed.

***

### 4. Resolution & Verification

**Do NOT rewire the thick main power cables.** The easiest and safest way to fix a phase mismatch is to rearrange the small voltage reference wires.

1. **Identify True Phases:** First, identify the true physical phases (L1, L2, L3) of the thick main wires passing through the meter holes by tracing them back to the main incoming supply or checking the breaker labels.
2. **Match with Multimeter:** Use **Method 3 (Multimeter)** to find the corresponding voltage reference wire for each phase (e.g., the small wire that reads \~0V against the L1 thick wire is your true `Va`).
3. **Rearrange Terminals:** Rearrange the small voltage reference wires (`Va`, `Vb`, `Vc`) on the meter's terminals so they perfectly match the physical wires passing through Hole 1, Hole 2, and Hole 3 respectively.
4. **Verification:** Before closing the panel, repeat **Method 1**. Turn on a resistive load and confirm that the Power Factor (PF) has returned to \~1.0 (100%) and the active power is positive on all phases.


# App & Cloud

### ⚡Quick Fixes

<details>

<summary><strong>Unable to Set High-Frequency Update Intervals in Zigbee2MQTT for Tuya Zigbee Products</strong></summary>

**Issue:** You are trying to set a high-frequency update interval (e.g., 5 or 10 seconds) for your SPM or SDM series Tuya Zigbee device, but the setting is not applied or supported.

**Context & Root Cause:** The intervals listed in the table below refer to the adjustable range available through the **"Update Frequency"** expose in Zigbee2MQTT (which is visible once the Product Model is loaded via MQTT).

Because Tuya's cloud platform imposes penalty restrictions on high-frequency data reporting, we had to restrict the minimum adjustable limits on older (EOL) models to ensure device stability. Currently, only newer Active models fully support high-frequency intervals down to 5 seconds.

**Supported "Update Frequency" Ranges by Model:**

<table><thead><tr><th width="223">Product Name</th><th width="113">Status</th><th width="200">Local Update Interval</th></tr></thead><tbody><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM01.html#tuya-spm01">Tuya SPM01</a></td><td>EOL</td><td>150-3600s</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM01V2.html">Tuya SPM01V2</a></td><td>EOL</td><td>150-3600s</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM01V2.5.html">Tuya SPM01V2.5</a></td><td>EOL</td><td>150-3600s</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM01V1-GT.html#tuya-spm01v1-gt">Tuya SPM01V1-GT</a></td><td>Active</td><td>5s-3600s</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM02.html#tuya-spm02">Tuya SPM02</a></td><td>EOL</td><td>300s-3600s</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM02V2.html">Tuya SPM02V2</a></td><td>EOL</td><td>300s-3600s</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM02V2.5.html">Tuya SPM02V2.5</a></td><td>EOL</td><td>300s-3600s</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM02V3.html#tuya-spm02v3">Tuya SPM02V3</a></td><td>Active</td><td>5s-3600s</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SPM02V1-GT.html#tuya-spm02v1-gt">Tuya SPM02V1-GT</a></td><td>Active</td><td>5s-3600s</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SDM01.html">Tuya SDM01</a></td><td>EOL</td><td>5s-3600s</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SDM01V1.5.html#tuya-sdm01v1-5">Tuya SDM01V1.5</a></td><td>EOL</td><td>5s-3600s</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SDM01V1-GT.html">Tuya SDM01V1-GT</a></td><td>Active</td><td>5s-3600s</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SDM02V1.html#tuya-sdm02v1">Tuya SDM02V1</a></td><td>EOL</td><td>150-3600s</td></tr><tr><td><a href="https://www.zigbee2mqtt.io/devices/SDM02V1-GT.html#tuya-sdm02v1-gt">Tuya SDM02V1-GT</a></td><td>Active</td><td>5s-3600s</td></tr></tbody></table>

⚠️ **IMPORTANT WARNING FOR EOL USERS:** If you are currently using an EOL product and your current update interval is *faster* than the new limits (for example, an SPM01V2 running at 30 seconds), **DO NOT perform an OTA firmware update** via the Tuya Zigbee gateway. Updating the firmware will force your device to adopt the restricted intervals listed above, and this process cannot be reversed.

💡 **PURCHASING TIP:** When buying new products, **please confirm the specific product version with your seller** to ensure it supports the high-frequency update intervals you need.

</details>

### 🛠️ Detailed Guides

* [Virtual ID for Tuya Connectivity Products](/troubleshooting/app-and-cloud/virtual-id-for-tuya-connectivity-products)  `[All Tuya Products]`&#x20;
* ["Failed to Add the Device" Error in Smart Life App](/troubleshooting/app-and-cloud/failed-to-add-the-device-error-in-smart-life-app)  `[All Tuya Products]`&#x20;


# Virtual ID for Tuya Connectivity Products

{% hint style="info" %}
**Applies to:** All Tuya Connecititvy Products | **Scenario:** Remote Support | **Updated:** 2026-04-25
{% endhint %}

### Virtual ID for Tuya Connectivity Products

If you encounter any operational issues with your connected devices **during daily use**—after the initial installation are complete—our technical support team can remotely diagnose the problem to provide a faster resolution. To do this, we will need your device's **Virtual ID**.

#### What is a Virtual ID?

The **Virtual ID** is a unique serial number assigned to each specific device. Providing this ID allows our technical support team to retrieve the device's cloud operational logs from the **last seven days**. This data is crucial for checking connectivity drops, error codes, and other anomalies without needing to inspect the device in person.

> 🔒 **Privacy Note:** Sharing your Virtual ID only grants our engineers access to the device's technical logs for troubleshooting purposes. It does not expose your personal account information.

***

#### How to Find Your Virtual ID

You can easily locate the Virtual ID of your device by following these steps within the **Smart Life app**:

1. **Open the Device Panel:** Open the Smart Life app and tap on the specific device you are experiencing issues with.
2. **Go to Device Settings:** Tap the **Edit/Settings icon** (usually a pencil `📝` or hexagon icon) located in the top right corner of the screen.
3. **Access Device Information:** In the settings menu, tap on **Device Information** (often indicated by an `ℹ️` icon).
4. **Copy the Virtual ID:** Look for the **Virtual ID** in the list. You can simply tap the **Copy** button next to it to save it to your clipboard.

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Ft5bA8QbM5XqObdESzurh%2Fimage.png?alt=media&amp;token=8753eb05-6018-4fb5-b9ea-b9af84688d20" alt=""><figcaption></figcaption></figure>

***

#### What to Do Next

Once you have copied the Virtual ID, please paste it into your support ticket, email, or chat window when communicating with our technical support team.

**Example format to send to support:**

* **Device Model:** \[e.g., Smart Plug Gen 2]
* **Issue Description:** \[e.g., Device goes offline every few hours]
* **Virtual ID:** `6cf2db04d11811623980ka`


# "Failed to Add the Device" Error in Smart Life App

{% hint style="info" %}
**Applies to:** All Tuya Connectivity Products | **Scenario:** Connectivity Issue | **Updated:** 2026-04-25
{% endhint %}

### 🔴 Symptom

When pairing SPM, SDM, or SRS series devices, the Smart Life app times out and displays a red **"Failed to add the device"** error message.

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2F9KhYxoG4OeAKAXVeWEyQ%2Fimage.png?alt=media&amp;token=1415680a-5fe8-4b10-b951-b0c03470b05e" alt=""><figcaption></figcaption></figure>

***

### 🟢 How to Fix

*Every Tuya-enabled device from Bituo undergoes strict factory testing before shipment. If you encounter this error, it is typically related to app compatibility or a product version mismatch. Please check the following two common causes:*

**1. Update the Smart Life App** Older versions of the app might not recognize our newest device firmware.

* **Action:** Go to the App Store (iOS) or Google Play (Android), update **Smart Life** to the latest version, and try pairing again.

**2. Verify Your Device Version** Bituo offers different connectivity versions for the SPM/SDM/SRS series. The Smart Life app **only** works with devices equipped with Tuya Wi-Fi or Tuya Zigbee modules.

* **Action:** Check the label on your device or your original order details. Ensure you have the **Tuya Wi-Fi** or **Tuya Zigbee** version. *(For example, versions like Standard Zigbee 3.0 or Open Wi-Fi are not compatible and cannot be added to the Smart Life app.)*

***

### 💬 Still Need Help?

If the issue persists after completing the steps above, please contact our support team at [**support@bituo-technik.com**](mailto:support@bituo-technik.com) with your device's serial number (SN) or order details. We are here to help!


# Why Are Values Not Displayed on Charts in the Smart Life App?

{% hint style="info" %}
**Applies to:** All Tuya Connectivity Products | **Scenario:** App & Cloud Issue | **Updated:** 2026-08-24
{% endhint %}

If your real-time values (voltage, current, power) display correctly on the dashboard, but historical charts (hourly, daily, or monthly graphs) show no data or abnormal values, the issue usually stems from Tuya's chart calculation logic or incomplete device reset procedures.

Follow this troubleshooting guide to diagnose and fix the issue.

***

#### Cause 1: Normal Cloud Data Aggregation Delay

The Tuya Cloud platform processes real-time telemetry into historical chart intervals on a schedule, rather than instantly.

* **Hourly Charts:** Require at least **1–2 hours** of continuous online operation after initial pairing before the first bar renders.
* **Daily / Monthly Charts:** Require at least **24 hours** of continuous logging to aggregate interval metrics.

> **Action:** If you recently paired the device, keep it powered on and connected for at least 2 hours before evaluating the charts.

***

#### Cause 2: Incomplete Reset — Cleared Cloud Data, But Skipped MCU Flash

When unbinding or resetting a device via **Remove and Clear Data**, Tuya generates a new Virtual Device ID and wipes the historical cloud database. However, **this action does NOT clear the total accumulated energy stored in the meter's local MCU Flash memory.**

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2FI7PyiMeONndoVwgpPVuG%2Fimage.png?alt=media&amp;token=62429a92-112b-429c-bb89-1c4e2602e5c5" alt="" width="188"><figcaption></figcaption></figure>

**Why This Causes Chart Issues**

Tuya handles chart rendering differently based on device categories:

* **Smart Relays:** Periodically report incremental energy changes (e.g., every 15 minutes).
* **Smart Meters (SPM/SDM):** Report the **absolute total accumulated energy** (kWh). The Tuya Cloud calculates daily/monthly usage by taking the difference between two timestamps.

If you reset cloud data without clearing the MCU, the meter will upload its existing high accumulated value (e.g., 45,800 kWh) to the freshly reset cloud account, leading to massive display **spikes or broken chart** calculations.

{% hint style="info" %}
**How to Completely Zero Out the Meter:** To ensure clean chart generation after a reset, you must clear both cloud and hardware memory:

1. **Clear Cloud Data:** In the Smart Life App, tap the **Edit (Pen) icon** -> **Remove Device** -> **Remove and Clear data**.
2. **Clear MCU Flash Memory:** Go to device page in App -> **Settings** -> **Energy Management** -> **Zero Energy** -> **Confirm**.<br>
   {% endhint %}

***

#### Cause 3: Incomplete Reset — Cleared MCU "Zero Energy", But Skipped Cloud Data

Conversely, if you trigger **Zero Energy** in the app settings without clearing the historical cloud records, Tuya's monthly delta logic will break.

**Example Scenario**

* Suppose your meter accumulated **45,800 kWh** in the cloud history.
* You tap **Zero Energy** (MCU resets to 0 kWh), but keep the existing cloud device profile.
* As the meter starts counting up again (1 kWh, 2 kWh, etc.), Tuya's monthly algorithm compares new incoming values against the highest recorded historical peak (45,800 kWh).
* Since the new values do not exceed 45,800, the cloud calculates a zero or negative difference and **fails to render any bars in the Monthly view** (even if Daily views show active readings).

<figure><img src="https://68488808-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FTmsWivaZjkubbVKrCezC%2Fuploads%2Foj5XcnezDUJ2DaOGp810%2Fimage.png?alt=media&amp;token=79f0c91b-8268-493f-a285-54086cf13881" alt="" width="548"><figcaption><p>Data appears in the daily view but is missing when switching to the monthly view.</p></figcaption></figure>

> **Solution:** Unbind the device using **Remove and Clear Data** in the Smart Life App, perform a **Zero Energy** reset, and re-add the device to reset both cloud baselines and local MCU registers simultaneously.

***

#### Additional Quick Checks

If the reset procedures above do not resolve the issue, check these environment settings:

* **Signal Strength & Offline Drops:** Ensure your Wi-Fi or Zigbee signal strength is sufficient (RSSI $\ge -70 \text{ dBm}$). Poor signal causes telemetry packet loss, leading to gaps in interval data.
* **App Time Zone:** Verify that your smartphone and Smart Life App profile are synced to your local time zone. Time zone mismatches can cause chart data to render outside the selected date ranges.

***

#### Still Need Help?

If you have verified all the steps above and your historical chart remains blank after 24 hours of operation, please contact our support team with:

* Device Model (e.g., `SPM01-D2TW`)
* Virtual ID (Found under *Device Settings* -> *Device Information*)
* A screenshot of your real-time dashboard and the empty chart page.


# BRCS Hardware Checklist

### ⚡Quick Fixes

### 🛠️ Detailed Guides


# Others

### ⚡Quick Fixes

### 🛠️ Detailed Guides


# Electrical Monitoring Devices

{% hint style="info" %}
**Status:** Active | **Updated:** 2026-10-03
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## SPM Series - Miniature Energy Meters

<table data-full-width="false"><thead><tr><th width="140">Model</th><th width="294.5555419921875">Description</th><th width="163.4443359375">Version</th><th>Download</th></tr></thead><tbody><tr><td><strong>SPM01 FLEX</strong></td><td>1-Phase Flexible Energy Meter</td><td>V3.2 (2026/05)</td><td><a href="https://downloads.bituo-technik.com/Datasheet/SPM01-FLEX-All_Datasheet_EN.pdf">⬇️ PDF</a></td></tr><tr><td><strong>SPM02 FLEX</strong></td><td>3-Phase Flexible Energy Meter</td><td>V3.2 (2026/05)</td><td><a href="https://downloads.bituo-technik.com/Datasheet/SPM02-FLEX-All_Datasheet_EN.pdf">⬇️ PDF</a></td></tr><tr><td><strong>SPM01 MCBM</strong></td><td>1-Phase MCB-Mounting Meter</td><td>V3.2 (2026/05)</td><td><a href="https://downloads.bituo-technik.com/Datasheet/SPM01-MCBM-All_Datasheet_EN.pdf">⬇️ PDF</a></td></tr><tr><td><strong>SPM02 MCBM</strong></td><td>3-Phase MCB-Mounting Meter</td><td>V3.2 (2026/05)</td><td><a href="https://downloads.bituo-technik.com/Datasheet/SPM02-MCBM-All_Datasheet_EN.pdf">⬇️ PDF</a></td></tr></tbody></table>

## SDM Series - Compact Energy Meters with Clamp CTs

<table><thead><tr><th width="142.11114501953125">Model</th><th width="295.4444580078125">Description</th><th width="153.7779541015625">Version</th><th>Download</th></tr></thead><tbody><tr><td><strong>SDM01 Combo</strong></td><td>3-Phase Meter with Clamp CTs</td><td>V2.2 (2026/05)</td><td><a href="https://downloads.bituo-technik.com/Datasheet/SDM01-Combo_Datasheet_EN.pdf">⬇️ PDF</a></td></tr><tr><td><strong>SDM02 SP</strong></td><td>Split-Phase Meter with Clamp CTs</td><td>V2.2 (2026/05)</td><td><a href="https://downloads.bituo-technik.com/Datasheet/SDM02_Datasheet_EN.pdf">⬇️ PDF</a></td></tr><tr><td><strong>SDM01 Combo Gen2</strong></td><td>3-Phase Meter with Clamp CTs (Gen2)</td><td>V0.5 (2026/07)</td><td><a href="https://downloads.bituo-technik.com/Datasheet/SDM01G2-Combo_Datasheet_EN.pdf">⬇️ PDF</a></td></tr><tr><td><strong>SDM01G2X</strong></td><td>3-Phase Meter with Clamp CTs and External Antenna </td><td>V0.3 (2026/05)</td><td><a href="https://downloads.bituo-technik.com/Datasheet/SDM01G2X_Datasheet_EN.pdf">⬇️ PDF</a></td></tr></tbody></table>

## SRS Series - Smart Relay Switches

<table data-full-width="false"><thead><tr><th width="141.66668701171875">Model</th><th width="299.111083984375">Description</th><th width="135.3333740234375">Version</th><th>Download</th></tr></thead><tbody><tr><td><strong>SRS01 1PM</strong></td><td>1-Channel Smart Relay Switch with Built-in Power Measurement(16A)</td><td>V1.1 (2026/02)</td><td><a href="https://downloads.bituo-technik.com/Datasheet/SRS01-1PM_Datasheet_EN.pdf">⬇️ PDF</a></td></tr><tr><td><strong>SRS01 2PM</strong></td><td>2-Channel Smart Relay Switch  with Built-in Power Measurement (2x10A)</td><td>V1.1 (2026/02)</td><td><a href="https://downloads.bituo-technik.com/Datasheet/SRS01-2PM_Datasheet_EN.pdf">⬇️ PDF</a></td></tr></tbody></table>
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## SPM Series - Miniature Energy Meters

<table data-full-width="false"><thead><tr><th width="148">Model</th><th width="269.6666259765625">Description</th><th width="151.888916015625">Version</th><th>Download</th></tr></thead><tbody><tr><td><strong>SPM01 FLEX</strong></td><td>1-Phase Flexible Energy Meter</td><td>V3.1.3 (2025/09)</td><td rowspan="4"><a href="https://downloads.bituo-technik.com/User-Guide/SPM0102-TWTZEWUZ-All-in-One_User-Guide_EU6Languages.pdf">⬇️ PDF</a></td></tr><tr><td><strong>SPM02 FLEX</strong></td><td>3-Phase Flexible Energy Meter</td><td>V3.1.3 (2025/09)</td></tr><tr><td><strong>SPM01 MCBM</strong></td><td>1-Phase MCB-Mounting Meter</td><td>V3.1.3 (2025/09)</td></tr><tr><td><strong>SPM02 MCBM</strong></td><td>3-Phase MCB-Mounting Meter</td><td>V3.1.3 (2025/09)</td></tr></tbody></table>

## SDM Series - Compact Energy Meters with Clamp CTs

<table><thead><tr><th width="148.11114501953125">Model</th><th width="289.4444580078125">Description</th><th width="144.7779541015625">Version</th><th>Download</th></tr></thead><tbody><tr><td><strong>SDM01 Combo</strong></td><td>3-Phase Meter with Clamp CTs</td><td>V1.1.1 (2025/10)</td><td><a href="https://downloads.bituo-technik.com/User-Guide/SDM01-All-in-One_User-Guide_EU6Languages.pdf">⬇️ PDF</a></td></tr><tr><td><strong>SDM02 SP</strong></td><td>Split-Phase Meter with Clamp CTs</td><td>V2.1 (2026/02)</td><td><a href="https://downloads.bituo-technik.com/User-Guide/SDM02-IEC-All-in-One_User-Guide_EU6Languages.pdf">⬇️ PDF-IEC</a><br><a href="https://downloads.bituo-technik.com/User-Guide/SDM02_UL-User-Guide_EN.pdf">⬇️ PDF-UL</a></td></tr><tr><td><strong>SDM01 Combo Gen2</strong></td><td>3-Phase Meter with Clamp CTs (Gen2)</td><td>V1.0 (2026/07)</td><td><a href="https://downloads.bituo-technik.com/User-Guide/SDM01G2_All-in-One-User-Guide_EU6Languages.pdf">⬇️ PDF</a></td></tr><tr><td><strong>SDM01G2X</strong></td><td>3-Phase Meter with Clamp CTs and External Antenna </td><td>V1.0 (2026/07)</td><td><a href="https://downloads.bituo-technik.com/User-Guide/SDM01G2X_All-in-One_User-Guide_EU6Languages.pdf">⬇️ PDF</a></td></tr></tbody></table>

## SRS Series - Smart Relay Switches

<table data-full-width="false"><thead><tr><th width="149.66668701171875">Model</th><th width="328.111083984375">Description</th><th width="140.3333740234375">Version</th><th>Download</th></tr></thead><tbody><tr><td><strong>SRS01 1PM</strong></td><td>1-Channel Smart Relay Switch with Built-in Power Measurement(16A)</td><td>V1.1 (2026/02)</td><td><a href="https://downloads.bituo-technik.com/User-Guide/SRS01-1PM_User-Guide_EN.pdf">⬇️ PDF</a></td></tr><tr><td><strong>SRS01 2PM</strong></td><td>2-Channel Smart Relay Switch  with Built-in Power Measurement (2x10A)</td><td>V1.1 (2026/02)</td><td><a href="https://downloads.bituo-technik.com/User-Guide/SRS01-2PM_User-Guide_EN.pdf">⬇️ PDF</a></td></tr></tbody></table>
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💡For 3D Assets, Certificates and DoC, please contact our support team <support@bituo-technik.com>


# Electronic Components & Systems

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### BRCS AC/DC Residual Current Sensors (IEC62955)

<table><thead><tr><th width="148.11114501953125">Model</th><th width="333.4444580078125">Description</th><th>Version</th><th>Download</th></tr></thead><tbody><tr><td><strong>BRCS01C IEC</strong></td><td>BRCS01C, Flexible, A30+DC6mA and DC6mA, 5V/12VDC</td><td>V1.3 (2025/01)</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BRCS01C-IEC_Datasheet_EN.pdf">📥</a></td></tr><tr><td><strong>BRCS03C IEC</strong></td><td>BRCS03C, PCB-mounting (Copper jumper), A30+DC6mA and DC6mA, 5V DC</td><td>V1.2 (2024/07)</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BRCS03C-IEC_Datasheet_EN.pdf">📥 </a></td></tr><tr><td><strong>BRCS03X IEC</strong></td><td>BRCS03X, PCB-mounting (Horizontal Through hole), A30+DC6mA and DC6mA, 5V DC</td><td>V2.1 (2025/01)</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BRCS03X-IEC_Datasheet_EN.pdf">📥 </a></td></tr><tr><td><strong>BRCS01V IEC</strong></td><td>BRCS01V, PCB-mounting (Vertical Through hole), A30+DC6mA and DC6mA, 5V DC</td><td>V1.4 (2025/04)</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BRCS01V-IEC_Datasheet_EN.pdf">📥</a> </td></tr></tbody></table>

### BRCS AC/DC Residual Current Sensors (CCID20 & IEC62955)

<table><thead><tr><th width="157">Model</th><th width="320.333251953125">Description</th><th>Version</th><th>Download</th></tr></thead><tbody><tr><td><strong>BRCS01C UL</strong></td><td>BRCS01C, Flexible, CCID20 and DC6mA/Type A 30mA+DC6mA, 5V/12VDC</td><td>V1.1 (2025/01)</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BRCS01C-UL_Datasheet_EN.pdf">📥 </a></td></tr><tr><td><strong>BRCS03C UL</strong></td><td>BRCS03C, PCB-mounting (Copper jumper), CCID20 and DC6mA/Type A 30mA+DC6mA, 5V DC</td><td>V1.3 (2025/01)</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BRCS03C-UL_Datasheet_EN.pdf">📥 </a></td></tr><tr><td><strong>BRCS03X UL</strong></td><td>BRCS03X, PCB-mounting (Horizontal Through hole), CCID20 and DC6mA/Type A 30mA+DC6mA, 5V DC</td><td>V1.4 (2025/01)</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BRCS03X-UL_Datasheet_EN.pdf">📥 </a></td></tr><tr><td><strong>BRCS01V UL</strong></td><td>BRCS03X, PCB-mounting (Vertical Through hole), CCID20 and DC6mA/Type A 30mA+DC6mA, 5V DC</td><td>V1.1 (2025/04)</td><td><a href="https://downloads.bituo-technik.com/Datasheet/BRCS01V-UL_Datasheet_EN.pdf">📥 </a></td></tr></tbody></table>

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# Service & Support

* Section 1: General FAQ (通用常见问题)
  * Ordering & Payment (如何下单、付款方式)
  * Shipping & Lead time (物流周期，针对欧/亚市场)
  * Compliance (REACH, RoHS, GDPR 说明)
* Section 2: Service & Policies (服务协议)
  * Warranty Policy (保修条款 - 硬件厂商的核心)
  * Return & Refund (退换货流程)
  * Privacy Policy (隐私政策)
* Section 3: Contact Us (联系我们)

  * Technical Support (技术支持入口)
  * Sales Inquiry (大客户/SI 询价)
  * Latest News

  Section 4: Change Log<br>

  #### 💡 最佳实践方案：把卡片改为“Changelog（更新日志）”

  建议你不要删除这个入口，但改变它的定位。把 `Product Updates` 改名为 Changelog 或 What's New，并采取以下策略：

  1. 卡片内容做成“时间轴”： 全局卡片只记录大版本或跨产品线的改进（比如：*2026-Q1: 全线设备 Zigbee 协议优化*）。
  2. 做成“链接集合”： 全局卡片内部不需要写具体细节，而是通过列表链接到各个 `Product Document` 里的具体 `Release Notes`。

<details>

<summary><strong>Do you offer ODM collaboration?</strong> <code>[SPM/SDM/SRS Products]</code></summary>

Yes, we offer ODM collaboration for most of our **Electrical Monitoring Devices**. We are glad to stay behind the scenes if an ODM business model can accelerate the digitalization of power distribution systems and make smart energy management accessible to more people.

**For hardware product brand customers**, our ODM program is primarily focused on:

1. **Electrical installation product brands** — promoting energy efficiency management within power distribution systems of homes, buildings, and infrastructure.
2. **Residential clean energy equipment brands** — including solar inverter, battery storage, and EV charger manufacturers whose products typically require local automation integration with energy meters for real-time control and optimization.
3. **Smart home product brands** — looking to expand their product line beyond home automation into energy management, extending their ecosystem from smart living to smart energy.

**For system integrators and total solution providers**, we understand your business is largely project-driven. For smaller projects, a standard off-the-shelf solution is likely the most practical path. However, for large-scale projects with significant volume and scope, we are fully committed to providing dedicated ODM support to help you deliver a tailored, competitive solution.

We can further provide **customer-specific design and customization** for ODM partners who have an ambitious and feasible plan to grow together.

</details>

<details>

<summary><strong>Where can I buy your products?</strong> <code>[All Products]</code></summary>

If you would like to purchase directly from us, there are currently two options:

* **Direct Contact (B2B & ODM):** You can reach out to us at **<info@bituo-technik.com>**. Whether you are looking for ODM collaboration or want to directly purchase our branded products in volume, our team is ready to assist you.
* **Official Online Store (Orders typically under $2,000 / €2,000):** For smaller orders or sample purchases, you can shop conveniently at our independent online store: [**shop.bituo-technik.com**](https://shop.bituo-technik.com). We offer **tiered volume discounts** directly on the site. Additionally, long-term customers can contact us to apply for an exclusive **loyalty partner discount**.

**Retail E-commerce Partners:** We also work with various retail e-commerce partners, primarily focusing on our Standard Zigbee 3.0 product lines. For instance, customers can also purchase our devices through **Domadoo** (France) at [**https://www.domadoo.fr/**](https://www.domadoo.fr/).

</details>


# Developer Platform

Welcome to your team’s developer platform

<p align="center">to be continued</p>