INA219 sensors and measure of the solar panel and lead acid battery

Thread Starter

Vít Zaoral

Joined Oct 8, 2019
I have two INA219 sensors, 18V/40W solar panel, solar charger controller and 12V lead acid battery. I want to measure the voltage / current on the battery and the same on the solar panel. I use the circuit that is attached in the attachments.

Battery measuring works nice, but solar panel voltage measuring is wrong. It shows same voltage as battery (so 12V), even if solar voltage gives for example only 5V. I think that solar charger controller somehow blocks voltage measuring, or is my circuit bad? Thank you.