I recently came across an exciting project where someone shared their code for connecting an ESP32 to a Danfoss solar inverter. The goal was to integrate this setup with Home Assistant (HA), but they were looking for help to finalize the integration. I thought this would be a great opportunity to explore the possibilities and share my journey.
The code provided uses an ESP32 with an RS485 to TTL converter board, which communicates with the Danfoss solar inverter. It retrieves various data points such as total production, instantaneous power, panel temperature, and more. The user mentioned that while the code works, they need assistance in setting it up within HA.
I decided to take on this challenge and started by understanding the code structure. The code uses a series of predefined strings for communication, including start frames, destination addresses, and specific commands to retrieve data from the inverter. The data is then parsed and converted from hexadecimal to decimal for readability.
One of the first steps I took was to ensure the ESP32 was correctly configured and communicating with the inverter. I tested the code on my setup and was able to retrieve data successfully. The next step was to figure out how to send this data to HA. I considered using MQTT as the communication protocol since it’s widely supported in HA and allows for easy integration.
I modified the code to include MQTT publishing functionality. This involved setting up the ESP32 as an MQTT client, connecting to my local MQTT broker, and publishing the retrieved data to specific topics. I also added error handling to ensure the connection remains stable and data is reliably published.
On the HA side, I created a custom sensor platform to listen to the MQTT topics and display the data in a user-friendly manner. I configured the sensors to update at regular intervals, ensuring real-time monitoring of the solar inverter’s performance.
Throughout this process, I encountered a few challenges, such as ensuring the ESP32’s MQTT client could handle the data volume without crashing and making sure the data parsing was accurate. However, with some research and testing, I was able to overcome these issues.
The end result is a seamless integration where I can monitor my solar inverter’s performance directly within HA. This has been incredibly useful for tracking energy production, identifying trends, and optimizing my solar setup.
I’d like to thank the original code contributor for sharing their work and the HA community for their support and resources. This project has not only enhanced my understanding of solar inverters and ESP32 programming but also provided a practical solution for monitoring my energy systems.
If anyone has questions or needs assistance with similar integrations, feel free to reach out! Happy coding and integrating!