> For the complete documentation index, see [llms.txt](https://docs.bituo-technik.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.bituo-technik.com/product-document/spm-series/spm02r-flex.md).

# SPM02R FLEX

{% hint style="info" %}
 **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.md)
{% endcontent-ref %}

***

### 10. Troubleshooting

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

### 11. Printed User Guide

### 12. Explore More

<br>