Why do RV's not play nice with GFCI circuits?

[NLOVNIT]

I've read a LOT of posts about RV's tripping GFCI protected circuits to which they are plugged in. I know this first hand because I've never been able to plug any of our RV's into the GFCI protected circuit outlets in my home garage (which would be the most convenient). What I've always had to do is connect to a non-GFCI protected outlet inside my home - which means running the cord under the garage door, through the garage, attached to a heavy duty extension cord, then leaving the door from the house to the garage open enough to get the extension cord into the house to an interior outlet. 99.9% of the time, my RV is just sitting out there, no appliances on & only the parasitic draws (i.e. microwave panel, LED light on the LPG detector or fantastic fan, cycling of the converter)

But WHY do they trip that breaker all the time? I've not actually read an explanation. Any electric experts out there who can answer this? I'm kinda one of those who wants an explanation.

[vsheetz]

Could be the GFCI itself. Has it been replaced? Perhaps try a 'hospital grade' or similar rated heavy duty GFCI.

If you want to try to isolate a ground fault source to a device or appliance during it's operation. Drop all breakers in the main/sub breaker panel. Then bring them on individually until it trips. Else it's a matter of disconnecting device or appliances - by unplugging or disconnecting wiring.

A ground fault may be occuring when the inverter relay transfers the neutral/ground bonding. It may be timing sensitive - so occurs intermittently.

Note. GFCI do not trip on excess power draw, rather a ground fault. Unless - its current sensor has saturated (ensure charger shore setting is reduced, no air conditioning on, etc). So excess current is a possibility. Ensure all high power draw items are turned off when connecting shore power.

[TacomaJoe]

If you were to plug your house into the neighbor's GFCI outlet, it would probably trip. My house water heater, furnace, lighting, stove etc are not on GFI circuits, only the outlets. I can add from my traffic signal experience we had a Radio Interference Filter that is guarantied to trip a GFI because of a capacitor between the hot and ground. It keeps all the switching "noise" of the equipment from affecting nearby radios but that connection will trip any GFI. The bonding of the neutral and ground wires will solve some of the issues but creates others.

It is not that fact of chaining GFCI outlets together. I just worked on the son's place and he had 4 GFCIs daisy chained with no problem, his issue turned out to be an extension cord laying in the yard with a little moisture on the exposed end.

[TacomaJoe]

Take what I say with a grain of salt. I just noticed on my signature that my truck hasn't been built yet. Edit coming.

[NLOVNIT]

Thanks, both of you.

Vince - that GFCI in the garage is at least 20 years old. Do they have a lifespan?

Joe - the moisture thing rings a bell. I used to have a fountain connected to a garage outlet. It needed an extension cord to get there & I had the connector ends inside one of those outdoor cord connection protectors, but if it was raining out or heavy dew, that fountain would trip the garage circuit every time.

[vsheetz]

Originally Posted by NLOVNIT

Vince - that GFCI in the garage is at least 20 years old. Do they have a lifespan?

At 20 years, age could be a factor.

[ArtJoyce]

I not 100 percent sure about this. But I think the issue is when you have one gfi circuit that is feeding another circuit such as power center in a RV. If the power center is bonded. It looks to the gfiand there is a short between ground and natural.

[vsheetz]

Originally Posted by ArtJoyce

I not 100 percent sure about this. But I think the issue is when you have one gfi circuit that is feeding another circuit such as power center in a RV. If the power center is bonded. It looks to the gfiand there is a short between ground and natural.

Should not be bonded in the RV circuit breaker panel. Nuetral/ground bonding is only done at the power source.

When on shore power, it's bonded there. When on generator, it's bonded in the generator. When on inverter, bonding is internal to the inverter.

There should be a relay in the inverter that lifts it's bonding when shore/genny is active (this is the transition I mentioned in another responce that can trip a GFCI).

[Jkwilson1989]

Usually either an improperly wired ATS or a compressor refrigerator. Properly wired, there is no reason a GFCI won’t work with an RV.

[Old-Biscuit]

GFCI trips on as little as 5ma difference between hot and ground
*Class A GFCI/5ma --- Class B GFCI/20ma

current leakage:
*adapters, extension cords, AC heater elements (water heater/fridge---fridge are common), moisture/dirt/dust

It doesn't mean there is a MAJOR electrical short ----just an imbalance it current flow (hot to ground)

[vsheetz]

Originally Posted by Old-Biscuit

GFCI trips on as little as 5ma difference between hot and ground
*Class A GFCI/5ma --- Class B GFCI/20ma

current leakage:
*adapters, extension cords, AC heater elements (water heater/fridge---fridge are common), moisture/dirt/dust

It doesn't mean there is a MAJOR electrical short ----just an imbalance it current flow (hot to ground)

As I understand - class A GFI is used for personnel protection and a class B is used for equipment protection.

[NITEHAWK]

Had similar problem with our coach when I tried to plug into an OLD, OLD cottage up by Lake Tomahawk, WI. Tried plugging a little idiot tell-tail wiring indicator and the wrong lights came on and told me the wiring in the cottage was reversed. So I made an adapter that I could change around the wiring in the adapter until the problems went away.

[Mile Marker 42]

Change your garage GFI to non GFI and call it a day.

[NLOVNIT]

I wonder why a GFCI is in my garage? I know they're code for any place there's a water source, but my garage doesn't have one. The only thing that gets wet in there is the floor if I pull my car in after driving it in the rain.