Mike, The 8 hours that you lost power was the coach plugged in to the 15amp recept? If so, then the inverter drained your batteries and when the power was restored it went into bulk charge which exceeds 20amps. If the coach was not plugged in then the power outage may have compromised the GFI recept you normally plug into. Another test you can perform is to turn all the circuit breakers off inside the coach except the 50amp main. Plug the coach in and turn the inverter breakers on only and wait 5 minutes and see what happens. If all good, turn the rest of the breakers on 1 at a time and wait on each one for a minute to help isolate the issue. Fred