Getting Started
OpenDTU supports the ESP32 family of microcontrollers.
Depending on the inverter to be addressed, different RF modules are required. The HM series requires the NRF24L01+ module, while the HMS/HMT series requires the CMT2300A module. Please see the inverter overview to see if your inverter is supported and to determine the required RF module.
For an easy start, use a "NodeMCU32 ESP32 DEVKIT DOIT" or "ESP32 NodeMCU Development Board" with an ESP32-S3 or ESP-WROOM-32 chipset on it.
Sample Picture:
Boards with Ethernet-Connector and Power-over-Ethernet are also supported. For example Olimex ESP32-POE or LilyGo T-Internet-POE
Steps to build your own DTU
- Determine the RF module you need
- Get a ESP32 module.
- Use a power suppy with 5 V and 1 A. The USB cable connected to your PC/Notebook may be powerful enough or may be not. Also the quality of the used USB cable might have an impact.
- Wire the module and RF module
- Wire a optional display
- Wire optional LEDs
- Flash the firmware via USB
- Upload a device profile which describes your hardware (or look at the profile first and connect your pins accordingly) using the Config Managment