GFI electrical question

My mind keeps coming back to inverter, if equipped. Feed through function.
Do you have an inverter? If yes, turn it off, then restart.
Does receptacle work on battery power through the inverter?
Try turning off all circuit breakers in the rig. Apply slight pressure toward off. Turn on main breaker, then branch breakers one at a time.
Does your rig have a detachable cord? Check connections in cord body.

I was having a GFCI tripping quiet often & replaced and kept tripping. I checked the wires in panel & found the neutral on the gnd bus and the gnd wire on neutral. Swapped wires to correct bus ( these should be set up as subfeed panels ) & no more nuisance trips. Why it had not done this for 8 years since new don't have a clue. Just something to check.

Do you have more than one GFCI outlet in the RV? And if so, does it also trip?

A GFCI outlet functions by comparing the amount of current flowing in the hot pin to the amount of current flowing in the neutral pin. They should be exactly the same. A difference of around 4 milliamps will trip the GFCI outlet. That difference means some of the current flowing into one pin is not reaching the other pin, i.e. some is “leaking” out somewhere. To be leaking out means it has to be reaching the power source (generator or shore power) via a ground path bypassing the outlet. And since ground and neutral are bonded at the source, that leakage gets back to the source neutral.

This makes me wonder if your generator ground is grounded to your trailer. Or your generator neutral is not bonded to generator ground. GFCI tripping when connected to shore power indicates you have a ground fault in one of your circuits or something plugged into one of those circuits. Not tripping on generator seems to indicate no ground path back to generator neutral.

Allworth wrote:
GFI needs a hard ground.

Generator power is a floating ground. You are grounded to the generator, not the power grid.

A GFCI requires no ground at all of any form. It is perfectly fine, and a good idea, to install GFCIs in place of old two prong outlets.

How would I ground to the shore power? I would think the 4 prong 50 amp cord would ground the unit??

I understand the not resetting unless powered and it was. Also does this on several different campgrounds. The comment on inverter was good but you would think it would do it on both generator and shore power. Not just the one. Thanks for relies

GFI needs a hard ground.

Generator power is a floating ground. You are grounded to the generator, not the power grid.

I would suggest you check shore power outlet with a meter along with shore power cord.

GFCI outlets can not be reset unless there is power coming in.

Check to see if you have an inverter feeding this receptacle.
Not being able to reset is a sign that there is no 120 volts AC to the receptacle.