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Introduction

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OpenDTU

Open Source software to talk to Hoymiles solar inverters. It is an alternative to their DTUs1 which sync everthing into the s-Miles cloud.

Note

You can only use one DTU for a specific inverter. You cannot query a inverter with two DTUs. Mixing up multiple DTUs may lead to an unexpected behavior!

Remarkable features

  • Read live data from inverter
  • Show inverters internal event log
  • Show inverter information like firmware version, firmware build date, hardware revision and hardware version
  • Show and set the current inverter limit
  • Show the current grid profile settings
  • Function to turn the inverter off and on
  • Supports up to 10 inverters
  • MQTT support (with TLS)
  • Home Assistant MQTT Auto Discovery support
  • Nice and fancy WebApp with visualization of current data
  • Firmware upgrade using the web UI
  • Time zone support
  • Ethernet support
  • Prometheus API endpoint (/api/prometheus/metrics)
  • English, german and french web interface (additional languages can be installed by uploading a language pack)
  • Displays (SSD1306, SH1106, PCD8544)
  • Status LEDs
  • Configuration management (export / import configurations)
  • Dark Theme

Features for developers

Background

This project was started from this discussion (Mikrocontroller.net). It was the goal to replace the original Hoymiles DTU (Telemetry Gateway) with their cloud access. With a lot of reverse engineering the Hoymiles protocol was decrypted and analyzed.

Support

For support using OpenDTU you can find us on Github or Discord:

Github Discussions Discord Chat

The firmware is opensource and free to use!

If you like this project you can show your appreciation by making a small donation. This will help with offsetting the cost of the different hardware devices we support.

Buy a coffee

  1. Data Transfer Unit ↩