SDM72 Modbus Library and Tool

This repository contains a Rust library and a command-line tool for interacting with Eastron SDM72 series energy meters via the Modbus protocol.

Table of Contents

• Hardware Requirements
• Technical Documentation
• Technical Specifications
• Installation & Compilation
• Command-Line Usage
• Library Usage
• Cargo Features
• License

Hardware Requirements

To use this tool, you need:

• An Eastron SDM72 series energy meter.
• A USB-to-RS485 converter (for RTU mode) or a Modbus TCP gateway.

Technical Documentation

For more detailed information, please refer to the official datasheets available in the docs/ directory:

• eastron_sdm72dmv2.pdf

Technical Specifications

Feature	Details
Nominal Voltage	230/400V AC (3~)
Operational Voltage	80%~120% of nominal voltage
Current Measurement	Up to 100A direct connection
Communication Protocol	Modbus RTU/TCP
Baud Rates	2400, 4800, 9600, 19200, 38400
Data Format	N, 8, 1 (No parity, 8 data bits, 1 stop bit)

Installation & Compilation

Prerequisites

Ensure you have the following dependencies installed before proceeding:

• Rust and Cargo: Install via rustup
• Git: To clone the repository
• A C compiler and linker

Building from Source

1. Clone the repository:

   git clone https://github.com/acpiccolo/SDM72-Powermeter.git
   cd SDM72-Powermeter

2. Compile the project:

   cargo build --release

   The compiled binary will be available at:

   target/release/sdm72

3. (Optional) Install the binary system-wide:

   cargo install --path .

   This installs sdm72 to $HOME/.cargo/bin, making it accessible from anywhere.

Command-Line Usage

View Available Commands

To list all available commands and their options, run:

sdm72 --help

Read All Values

For RTU Modbus (RS485) connected devices:

sdm72 rtu --address 1 --baudrate 9600 read-all

For TCP Modbus connected devices:

sdm72 tcp 192.168.0.222:502 read-all

Daemon Mode with MQTT

You can also run the tool as a daemon that publishes data to an MQTT broker. The connection is configured via an mqtt.yaml file.

sdm72 rtu --address 1 --baudrate 9600 daemon mqtt

Library Usage

The sdm72_lib crate provides two main ways to interact with the SDM72 energy meters:

1. High-Level, Safe Clients: Stateful, thread-safe clients that are easy to share and use in concurrent applications. This is the recommended approach for most users. See tokio_sync_safe_client::SafeClient (blocking) and tokio_async_safe_client::SafeClient (async).

2. Low-Level, Stateless Functions: A set of stateless functions that directly map to the device's Modbus commands. This API offers maximum flexibility but requires manual management of the Modbus context. See the tokio_sync and tokio_async modules.

Quick Start: Synchronous Client

Here's a quick example of how to use the synchronous SafeClient to read all values over a TCP connection.

Dependencies

First, add the required dependencies to your project:

cargo add [email protected] --no-default-features --features "tokio-tcp-sync,safe-client-sync,serde"
cargo add [email protected]
cargo add tokio@1 --features full

Example Usage

use sdm72_lib::{
    protocol::Address,
    tokio_sync_safe_client::SafeClient,
};
use tokio_modbus::client::sync::tcp;
use tokio_modbus::Slave;
use std::time::Duration;

fn main() -> Result<(), Box<dyn std::error::Error>> {
    // Connect to the device and create a stateful, safe client
    let socket_addr = "192.168.1.100:502".parse()?;
    let ctx = tcp::connect_slave(socket_addr, Slave(*Address::default()))?;
    let mut client = SafeClient::new(ctx);

    // Use the client to interact with the device
    let values = client.read_all(&Duration::from_millis(100))?;

    println!("Successfully read values: {:#?}", values);

    Ok(())
}

Cargo Features

This crate uses a feature-based system to minimize dependencies. When using it as a library, you should disable default features and select only the components you need.

• default: Enables bin-dependencies, intended for compiling the sdm72 command-line tool.

Client Features

• tokio-rtu-sync: Synchronous (blocking) RTU client.
• tokio-tcp-sync: Synchronous (blocking) TCP client.
• tokio-rtu: Asynchronous (non-blocking) RTU client.
• tokio-tcp: Asynchronous (non-blocking) TCP client.

High-Level Wrappers

• safe-client-sync: A thread-safe, stateful wrapper for synchronous clients.
• safe-client-async: A thread-safe, stateful wrapper for asynchronous clients.

Utility Features

• serde: Implements serde::Serialize and serde::Deserialize for protocol structs.
• bin-dependencies: All features required to build the sdm72 binary.

License

Licensed under either of

• Apache License, Version 2.0, (LICENSE-APACHE or http://www.apache.org/licenses/LICENSE-2.0)
• MIT license (LICENSE-MIT or http://opensource.org/licenses/MIT)

at your option.