/sml_to_mqtt

Reads SML data from an Landis+Gyr E220 power meter and publishes to MQTT for Home Assistant

Primary LanguagePythonMIT LicenseMIT

Converting SML to MQTT

This sml_to_mqtt.py runs on a Rasberry Pi. It reads SML energy data from a Landis+Gyr E220 energy meter and publishes that data to MQTT to Home Assistant.

imgs/block_diagram.drawio.png

How to run

Start sml_to_mqtt.py from the project directory

username@raspberrypi:~/Desktop/sml_to_mqtt $ python sml_to_mqtt.py

OR

Let crontab run the program upon reboot. To do so, open crontab in edit mode:

username@raspberrypi:~/Desktop $ crontab -e

and add the following line

@reboot python /home/pi/Desktop/sml_to_mqtt/sml_to_mqtt.py &

How to configure

Configuration is done via setting.yaml and entities.yaml (parameters documented within the files) as well as an secrets.yaml, which is not part of this repository. It must hold MQTT username and password in the form:

mqtt_auth:
  user: YOUR_MQTT_USERNAME
  password: YOUR_MQTT_PASSWORD

Notes to the development

  • The SML decoder is inspired by https://github.com/huirad/pysml´.

  • When applying that SML decoder to my particular Landis+Gyr E220 energy meter I found only two "offsets" to be useful:

    offset Interpretation MQTT entity
    171 Meter value 1.8.0 in kWh energy_imported
    202 Meter value 2.8.0 in kWh energy_exported

  • The MqttDevice class is reused from the Raspi_Walli_MQTT project.