OpenNETek
You have a Smart Inverter with a name like SG600MD and it looks like this?
Then this might be of use to you :)
This repo is inspired by a comment in the NETSGPClient Project ( https://github.com/atc1441/NETSGPClient/issues/13#issuecomment-1147458860 ) which was a quick and dirty way of throwing some example code together and the result was a firmware for an esp that offers a webgui and mqtt capabilities. I loved it so much that I created this here to iron out some issues.
This project offers ESP firmware that improves inverters from newenergytek ( www.newenergytek.com ) sold under many brands. They can be bought from AliExpress, Amazon etc. . They have very limited monitoring capabilities via proprietary "databoxes" which transfer the serial interface unencrypted over the air. Newer Versions (gen3) have a Smart Life/Tuya CBU adapter that works only with the smart life app via a cloud service hosted from china.
The idea is to put an ESP into the inverter to connect it to wifi. The ESP reports performance data via MQTT and offers a simple web page - all without the need of any cloud service.
Guide:
Hardware modification:
- open inverter
- remove LC12S wireless uart module "LC12S" (6 pins, 4 used)
- flash image onto your ESP (depending on your ESP connection to the inverter, you might power the inverter logic when connecting USB to the ESP to flash it. So better do it unconnected) You can update the firmware later using
http://opennetek-<InverterID\>/updatewithout usb connection. This way the esp can stay in the inverter and still receive firmware updates. - connect your ESP to the now free 3.3v, GND, RX and TX pins where the LC12S was connected to. The pinout is:
- black is ground
- yellow is RX (which goes to TX of the ESP32, which is PIN17)
- white is TX (which goes to RX of the ESP32, which is PIN16)
- red is 3.3v
- (optional) remove blue plastic on thermal pads if neccessary. mine were still on. (also on the back of the mainboard)
Configuration:
- after connecting DC power to the inverter, the ESP32 initializes
- after a minute or so: connect to SSID:OpenNETek Pass:opennetek!
- a captive portal pops up and you can enter wifi, mqtt details and the inverter-id from the chassis
- after that, the inverter publishes performance data via mqtt and http (Accessible via
http://opennetek-<InverterID\>.local/from the same Network)
I suggest using an ESP with the possibility to connect an external antenna. This way you can repurpose the hole (and even the antenna) from the LC12S. I used ESP32-WROOM-32U, ESP32C3 and also ESP8266.
Beware: some ESP with external antenna socket and internal antenna need hardware modification to "switch" to the external antenna.
