> 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/spm01r-flex.md).

# SPM01R FLEX

{% hint style="info" %}
 **Applies to:** SPM01R FLEX | **Hardware Revision:** V1.0+ | **Last Updated:** 2026-07-18
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### 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.md)
{% endcontent-ref %}

***

### 10. Troubleshooting

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

***

### 11. Printed User Guide

***

### 12. Explore More