I’m using the Automation HAT Mini for a solar monitoring system in a shed. The 3 A/D channels are used to record 5vdc (From PI), 3vdc (from Pi), and 12vdc from Solar charged 12vdc AGM battery(100 AH).
The 12vdc channel has suddenly started to randomly provide bad (low) readings which causes the system to send me alerts. I think the A/D circuit is malfunctioning on the board, how can I get a replacement? As you can see in the log files below, the 12vdc goes from a low (12.2vdc) to a normal (13.82vdc) in 1 minute.
Hear are some sample log files of the readings:
09-23-25 12:21:24 PM
Temp=82.0ºF, Humidity=41.5%
One Wire Temp:88.7 °F
Pi Voltage:5.19 vdc
3.3 Voltage:3.26 vdc
Batt Voltage:12.2 vdc
Battery Percent:60
09-23-25 12:22:37 PM
Temp=82.2ºF, Humidity=41.4%
One Wire Temp:88.7 °F
Pi Voltage:5.19 vdc
3.3 Voltage:3.26 vdc
Batt Voltage:13.82 vdc
Battery Percent:100
Can you test your ADCs with a bench power supply with given voltages? This would rule out any other source of error.
unrelated: I would recommend the INA3221 for your setup. It is a 3 channel voltage/current monitor and it is ideal for measuring solar, battery and load at the same time.
The ADC works fine most of the time and reads the proper 12vdc as I can check it against the readout on the solar charge controller. I’ve been to the shed when it was going whacky and compared readings with the controller.
As for the INA3221, the Mini is doing more than just monitoring voltages. It also reads the temp in the shed and controls ventilation fans. The mini also controls a cooling fan for the PI as it is all mounted in a sealed enclosure.
I still think the ADC has developed a bad channel.
As I said: try to isolate the problem and test it with a bench supply. If this shows that the channel is faulty, you can write to support and ask for a replacement. You can also skip the first step and hope that they don’t ask too many questions. They usually don’t.