Shore GFI opens when RV is plugged in to it.

teddyu wrote:
GFCI should not be use to power an RV. The AC refrig and water heaters are prone to causing the GFCI to trip. Change to a non-GFCI receptacle. JM2¢...

GFCI are used for a purpose to protect life and property.
Tripping GFCI are either indicating a problem or have become defective.
Us and ohm meter and check for continuity between the ground and neutral on the coach when not connected to shore power you should show no reading...
ie no continuity between the two.

Look up neutral ground fault and you will find a good deal about your situation. My TT had the same problem and the culprit was the electric heating coil in the water heater. The coil element shroud failed allowing the element to be exposed to water, this allowed current to flow rather than to the circuit neutral as it should, to ground hence tripping the GFI at the shore.

I was able to find the problem by disconnecting each neutral 1 at a time at the camper breaker box and plugging back into the gfi. The gfi did not trip when I disconnected the heating coil neutral so I figured it was the coil.

Good luck.

This happened to me when connecting to a GFI campground plug.
Problem was found in the RV breaker panel. The routing of a bare copper
ground wire was such that it was just touching the a neutral connector bar
inside the panel. This may have happened from road vibration while traveling.
re-routed the bare wire to the out side edge of the inside of the breaker box and
all was OK after that.

wa8xym
Thank you for your learned response. Shutting down all A/C ckt bkrs was one of the first items I had preformed. I had previously worked my way thru voltage and continuity (resistance) checks to the ATS. With shore and gen disconnected from the ATS. Connected shore and gen (no power applied condition) to ATS, applied GFI shore and it went off line. The ATS is 11 years old...never opened. Believe a high resistance (just high enough to cause a voltage differential to set the GFI off) between shore contacts and the ckt bkr panel contact in the ATS. One of the reasons I wanted to locate a complete internal wiring diagram of the ATS301. As the ATS has in internal converter/rectifier for the ATS coil and the time-Delay ckt.

I see a lot of information of questionable accuracy.

Many motor homes do not play nice with GFCI, some older units they actually bonded neutral and ground (A guaranteed tripper of GFCI systems) some may have an improperly wired inverter or power monitor/manager that does it. Some a partial short in a heater element (Water or Fridge)

Some converters do not play nice, either tripping when batteries are empty, or full.

HOW TO TRACK

First, Turn off ALL circuit breakers in motor home.. Now plug in your adapter and your motor home to one half of a 15 amp duplex outlet.

Plut a trouble lamp, drop lamp or whatever you call it into the other half, run cord of drop lamp in via window so you can see it.

now, one at a time, starting with the main breaker(s) (if 50 amp there will be 2 ganged, teat them as "#1" turn on the breakers, count to 5 turn on the next and keep doing this till darkness ensues (The Drop lamp goes out). NOTE which breaker that was, turn it off, reset outlet, and continue with the rest of the breakers till you have identified EVERY one that turns off the light.

Post the results here.. Breaker name and what it powers.

NOTE: in some cases, even with all breakers OFF it will trip. that too is helpful so if that's the case.. POST.

papakilo42 wrote:
I have a 2004 Coachmen Leprechaun 292. Opens the shore GFI. The shore GFI operates fine with tools and other loads. Just reacts to the RV. Coach circuit breakers in off position, A/C off. When the Onan/Cummins Generator is ON Line all Coach circuits operate normally, including the A/C. I am a novice at troubleshooting RVs without wiring diagrams and specific information concerning the Energy Conditioner unit, ATS #032-00061 opt. G, Gen time-out circuit for the ATS, and what voltage/resistance/continuity measurements I should see at various connections. Where is the rectifier/diode for the ATS coil? I have been in the electronics/electrical fields for over 50 years and have never worked with RVs or not been able to obtain wiring diagrams.
Any assistance or wiring diagrams will be appreciated.
Additional Info: RV has been connected to a shore GFI for 5 years, without problems. Operation of GFI: It senses a difference of potential between Ground and Return of shore lines. The generator cannot have the Return and Ground leads connected. The generator A/C lines are normally disconnected by the ATS in Shore Power use.

It only takes 4 - 6 ma of current flow to trip a GFI (UL approval requires 5 ma)and not something a human can even feel, so any little thing at all, will trip it and long before it ever becomes a safety issue. I once had a coach that would trip the GFI when operating the rear ac directly from it. Best thing to do, other than going crazy trying to find it, is to not use a GFI for coach power and if a campground pedestal, use one of the 30 or 50amp outlets with a converter cord and whatever other adapters are necessary.

rgatijnet1 wrote:
Since it is a GFI outlet, it is NOT a 30 amp or 50 amp RV outlet. I would check the pig-tail first for a loose wire that is causing the GFI to trip.

But it could be.

30 GFI circuit breaker

Since it is a GFI outlet, it is NOT a 30 amp or 50 amp RV outlet. I would check the pig-tail first for a loose wire that is causing the GFI to trip.

I has the same problem when plugged into my garage outlet and finally figured out the MH and GFI were simply not compatible so I pulled the GFI and replaced it with a non-gfi.

No longer an issue though as I had a 50A RV outlet installed. I always found it interesting that a 20 A outlet had GFI but a 30A RV outlet does not. That sort of tells you something.

gfci's dont like reverse polarity. maybe as simple as that.