MQTT INA3221 Triple-Channel Shunt Current Voltage Sensor via IIC I2C I²C WLAN on Tasmota D1 Mini

Thread Starter


Joined Apr 12, 2024
I would like to monitor the DC voltages of my solar system and broadcast those via MQTT.
For now I have no current monitoring planned with this IC.

But I am more than happy about your suggestions on how to monitor 200A@60V and 20@120V

The battery bank voltage can go up to 65V
The solar panels to 150V
The INA3221 module can do maximum 26V

65V 1kOhm/670Ohm=26.078V (Voltage Divider)
The ratio is ‭‭‭‭2.492522432701894‬‬?
So 1V would be ‭‭0.4012V?

150V 1kOhm/210ohms=26.033V
The ratio is ‭‭5.76191756616602‬
So 1V would be ‭‭0.1735533333333333‬‬V

Do these resistor values make sense? What resistors to use, 1% 0.1%... I am not sure what even excists and need to verify.

I was planning on doing this via ESP8266 or ESP32 and tasmota I2C broadcasting over MQTT.