I live in a rural area that has frequent power outages (Several per month. Less than a minute in duration). When the power is restored, several GFI outlets always trip. I am trying to track down the cause of these trips, as one of the outlets powers a livestock water heater (Which needs to stay powered during freezing months) for the safety of the animals.
The GFI outlets that trip are connected to a sub panel that is fed from the main panel. Turning the breaker that feeds the sub panel off and on also reliably trips the GFI outlets in question. I have reproduced this with nothing plugged into the outlets (And load side of GFI disconnected).
This problem has occurred ever since the GFI outlets were installed (Several years ago).
I am looking for the next troubleshooting steps to solve this issue.