Because your home breaker does not trip when you have the trailer main breaker turned off but trips when turned back, that would indicate a ground fault somewhere on a branch circuit in the trailer. I would turn off ALL branch breakers in the converter panel and one by one, turn a branch breaker on and off until you find one that trips the house breaker. There are a number of things that can cause a ground fault inside an RV, one of which is a faulty heater element. If it appears that it is the element, try turning the heater off at the switch at the heater and see if the house breaker still trips. If it does, it should be a faulty element.
A weak or defective GFCI receptacle (or breaker) is the last thing that should be suspected. If they trip on ground fault (and not from overload or short circuit), then it is just doing it's job and protecting someone from a shock.
BTW, having GFI receptacles in series is not a great idea. Not unsafe but they can "fight" each other and one or the other can trip. For example, you could actually have a ground fault downstream of a GFI receptacle in the trailer but the house GFI is tripping instead.
DonkeyEars wrote:
Well, absolutely everything is turned off in the trailer. The home circuit is a gfi breaker, I just push the button to reset. I don't think it's the home breaker, I run my compressor, power washer etc off this circuit. The shore power cable does have some cracks in it next to the metal prongs. It could be the shore cable as suggested. I tried turning off the trailer main ac breaker, and no home breaker kicked off. But it did kick off the home breaker as soon as I turned on the trailer main breaker. Unless there's any other suggestions, it looks like a new cable to me. Thanks a bunch.
