Owen on Nostr: Why isnt the current sensor on the Battery Line? If you want to measure charge ...
Why isnt the current sensor on the Battery Line? If you want to measure charge current/drain from the unit you need to monitor the battery, not the solar panel.
The wiring in the diagram looks fine at first:
BUT; using this current senso on on the high side of the solar panel, is dangerous.
- on a sunny day, once the battery is charged, the voltage on the solar panel + line might get quite high
- the INA219 is only rated to 26V on the sensor side (relative to the 0v line of the I2C bus)
- If the solar+ voltage gets high enough and there is a significant breakdown or leakage from the current sensor to the RAK, it will kill the module.
- This is very dependent on the panel size and specs! With a small panel you will be OK; but use a large panel and ???
I basically think the circuit is 'wrong', it measures the wrong current, in the wrong place.
The wiring in the diagram looks fine at first:
BUT; using this current senso on on the high side of the solar panel, is dangerous.
- on a sunny day, once the battery is charged, the voltage on the solar panel + line might get quite high
- the INA219 is only rated to 26V on the sensor side (relative to the 0v line of the I2C bus)
- If the solar+ voltage gets high enough and there is a significant breakdown or leakage from the current sensor to the RAK, it will kill the module.
- This is very dependent on the panel size and specs! With a small panel you will be OK; but use a large panel and ???
I basically think the circuit is 'wrong', it measures the wrong current, in the wrong place.