lrswss / esp32-sml-multi-reader

ESP32 reads SML messages from multiple smart electricity meters using an IR reading head and publishes decoded data via MQTT

Read and publish data from multiple smart meters with an ESP32 microcontroller

Motivation

As part of a small project, data from several smart meters in a large meter cabinet (all equipped with a SML IR interface) had to be read more or less simultaneously and published via MQTT. To avoid installing an ESP8266 with Tasmota and IR reading head for each electricity meter, this firmware was developed for an ESP32 microcontroller that can read SML messages from up to eight smart meters simultaneously using RTOS tasks.

Features

• based on sml_parser library
• read data from up to 6 smart meters simultaneously
• publish readings with timestamp to MQTT broker
• optional MQTT authentication
• TLS support

Hardware components

• ESP32 development board (e.g. Wemos LolinD32)
• multiple SML IR reading heads
• 3D printed IR reading head housing with 27mm neodymium ring magnet
• 5V USB power supply

Upload firmware

To compile the firmware for the ESP32 controller just download Visual Studio Code and install the PlatformIO add-on. Open the project directory and adjust the settings in include/config.h to your needs.

Since the software was developed on a MacBook you might need to adjust the upload port settings in the section [common] in platformio.ini. For further firmware updates use the OTA option in the web interface.

Contributing

Pull requests are welcome! For major changes, please open an issue first to discuss what you would like to change.

License

Copyright (c) 2023 Lars Wessels
This software was published under the Apache License 2.0.
Please check the license file.