A Domoticz Python plugin for reading Eastron SDM energy meters over Modbus RS485.

Supports multiple meters on a single RS485 bus from one plugin instance — no more serial port conflicts or duplicate hardware entries.

• Domoticz 2023.2 or newer
• USB to RS485 converter module (e.g. CH340, FTDI, etc.)
• Python 3 (included with Domoticz)

cd ~/domoticz/plugins
git clone https://github.com/gizmocuz/SDM630-Modbus
sudo systemctl restart domoticz

Copy the example configuration file and edit it for your setup:

cd ~/domoticz/plugins/SDM630-Modbus
cp config.json.example config.json
nano config.json

Define each meter on your RS485 bus:

{
    "meters": [
        {"name": "Shed", "type": "SDM72V2", "id": 1, "offset": 0, "enabled": true},
        {"name": "House", "type": "SDM120", "id": 2, "offset": 1, "enabled": false},
        {"name": "Garage", "type": "SDM630", "id": 5, "offset": 2, "enabled": true}
    ]
}

1. Go to Setup → Hardware
2. Select Eastron SDM630-Modbus from the Type dropdown
3. Set the serial port (e.g. /dev/ttyUSB0)
4. Set the baud rate (must match your meters, typically 9600)
5. Set the poll interval in seconds (minimum 5)
6. Click Add

The plugin reads the meter configuration from config.json — the Domoticz hardware page only configures the serial port and timing.

sudo systemctl restart domoticz

Check the Domoticz log for:

Eastron Modbus plugin started. 2 meter(s) configured.

• Each meter must have a unique Modbus ID configured on the meter itself (via the meter's front panel menu)
• Each meter must have a unique offset value in config.json
• Disabled meters are skipped entirely — no serial traffic, no devices created
• If a single meter fails to respond, the plugin logs the error and continues polling the remaining meters
• The plugin uses a single serial port connection, polling meters sequentially to avoid RS485 bus collisions

Forked from MFxMF/SDM630-Modbus. Register definitions based on nmakel/sdm_modbus.