Ground fault when I plug into 120 v outlet

If it is a GFCI there likely is your problem. Two GFCIs dont play nice together.

donn0128 wrote:
If it is a GFCI there likely is your problem. Two GFCIs dont play nice together.

I'm sorry but that's not true, you can gave a thousand of them linked together w/ no issue.
OP, you have a fault and need to find it. Probably fridge heater.

My first thought would be your adapter.
Disconnect the shore power cord from the adapter, then plug adapter only into the GFCI receptacle. If it trips, get a new adapter!

Neither a generator nor a standard 50A RV outlet has a ground fault interruptor on them, and so a ground fault (except a low-impedance hot to ground fault that carries a lot of current) will never trip them.

As ScottG says, there's a fault somewhere, and while finding a ground fault can sometimes be tricky, it's something that needs to be fixed and under the right (wrong?) circumstances could be a genuine safety hazard. Fridge and water heater elements leaking a bit of current are common sources of ground faults. A neutral wire making contact with ground somewhere also is not uncommon, and can be less than easy to locate.

Occasionally it is possible that individual harmless leakages, expected ones from things like RFI filters on the inputs of grounded electronic devices, can add together enough to make a ground fault interruptor trip. This is comparatively rare, though.

One way to begin troubleshooting is to start with all the breakers in the RV turned off and see if the GFCI trips. If it does, look for a neutral/ground fault--possibly in the breaker box, possibly somewhere else. If it holds, turn on the main breaker, and then the branch circuits one by one until you find one that is causing the fault.

I have isolated the refrigerator and I have tried totally separate adapters so I know that neither of those is the problem. I am running off of my generator right now and it's pulling about 900w but that's probably because the charger is in high-level charge. I will wait to see what it drops to. I can't imagine any other load that could be demanding 900 watts

If it is a GFCI there likely is your problem. Two GFCIs dont play nice together.

When I plug the RV into a GFCI outlet, then use a hair dryer in the RV, there are GFCIs chained. Never had a problem. When I plug the pressure washer into a GFCI outlet there are 2 GFCIs chained. Never had a problem.

A GF has nothing to do with high current loads. It can happen with the smallest load.
Also, just flipping a breaker doesn't always isolate a possible GF source. Try unplugging the fridge, water heater, etc.

Only issue with multiple GFCIs in series is which one will trip first. Could be the shore power cord itself and I would start by checking that and if okay, then move onto other things inside the RV. As mentioned, could be something as simple as a bad adapter.

I have a similar annoying problem. My RV has a hybrid Magnum inverter/charger. Some 15 amp outlets "hate" the Magnum--and others are just fine. It is totally hit and miss.

If you turn off ALL the breakers in the RV does it still trip?
Yes? Probably in the supply cord, transfer switch, adapter etc before the panel.
No? Turn on one main and then one branch at a time on that side. Then to the other main and branch circuits. Make a note of what breaker trips the GFCI.