30A GFCI on Pedestal Tripping

Topic: 30A GFCI on Pedestal Tripping (Read 1713 times) previous topic - next topic

30A GFCI on Pedestal Tripping

July 22, 2025, 03:43:06 pm

I am at a campground that has a GFCI on the 30A circuit (no 50A). The GFCi trips as soon as the transfer switch on the coach kicks in. I have run into this problem a couple times before. I tried narrowing down the problem by first turning off all of the 110 breakers. The ground fault trips as soon as I turn on the main breaker, even with all the other breakers off. Just to be certain, I pulled all the breakers from the main panel except the main, and pulled the main breaker from the secondary panel, and it still trips as soon as I turn on the main breaker in the coach and the transfer switch engages. I have enough solar to get by with everything but the air conditioning, but I would like to figure out what is causing the problem.

Re: 30A GFCI on Pedestal Tripping

Reply #1 – July 22, 2025, 04:31:00 pm

Which GFCI - one in the coach or does the campground have one at the site breaker?

Re: 30A GFCI on Pedestal Tripping

Reply #2 – July 22, 2025, 05:04:41 pm

It is possible that in your transfer switch or the breaker panel the ground and neutral are attached together. If a gfci sees this it will trip out. Check with a VOM meter and verify that you do not have any continuity between the neutral and ground wire.

You probably will have the neutral and ground connected on the generator side, but this should be isolated by the transfer switch from showing up when connected to shore power.

You may need to disconnect the neutral wires one by one, with the breaker off, to find where the problem of the GFCI tripping.

Re: 30A GFCI on Pedestal Tripping

Reply #3 – July 22, 2025, 06:31:40 pm

Quote from: Michelle – July 22, 2025, 04:31:00 pm

Which GFCI - one in the coach or does the campground have one at the site breaker?

The one on the site's pedestal.

Re: 30A GFCI on Pedestal Tripping

Reply #4 – July 22, 2025, 07:22:05 pm

Quote from: dbennett9 – July 22, 2025, 06:31:40 pm

The one on the site's pedestal.

Out of curiosity, what inverter/charger do you have?

ETA - I have seen some recent articles regarding RV parks adding GFCI to their site electrical hookups. We've not encountered it ourselves and I don't believe code currently requires it for 30 or 50 amp, only 15/20 amp.

ETA2 - just found this RVIA article Grounding Monitor Interrupters On RVs And Its Impact On RV Campgrounds | RVIA which states

On the RV Park side, it was suggested that Ground Fault Circuit Interrupter (GFCI) receptacles for the 30A and 50A services be installed on the RV pedestal. That suggestion was not adopted because electrical leakage current from the various electrical devices in an RV would cause a nuisance trip of the GFCI.

Re: 30A GFCI on Pedestal Tripping

Reply #5 – July 22, 2025, 07:23:27 pm

Can run power to another pedestal maybe the gifs weak

Re: 30A GFCI on Pedestal Tripping

Reply #6 – July 22, 2025, 10:48:10 pm

Gfci was required on RV pedestals per the National Electrical Code (NEC) Shortly later they removed the required for RV parks. This Gcfi 30 amp receptacle was either installed when the NEC required, insurance required, or inspector required it. Inspectors are almost God, majority of the time, when an electrical inspector says that we have to do something, contractor do it to get job inspection passed.

It is possible that an old inverter/charger could be causing the problem.

Re: 30A GFCI on Pedestal Tripping

Reply #7 – July 23, 2025, 12:32:54 am

If you said the pedestal did not trip until coach main breaker was closed, would leave out the transfer switch as it would close as soon as coach power was present at the transfer switch.

Re: 30A GFCI on Pedestal Tripping

Reply #8 – July 23, 2025, 11:01:21 pm

Quote from: Michelle – July 22, 2025, 07:22:05 pm

Out of curiosity, what inverter/charger do you have?

It is a Xantrex Prosine 2.0. I believe it is the original inverter/charger.

Re: 30A GFCI on Pedestal Tripping

Reply #9 – July 23, 2025, 11:04:26 pm

Quote from: fatheeler – July 22, 2025, 07:23:27 pm

Can run power to another pedestal maybe the gifs weak

The entire electrical system at this park is new as of this season, so it is unlikely the GFCI is bad. Plus, I have had this issue in the past at other parks with ground fault protection, so I believe the problem is with the coach.

Re: 30A GFCI on Pedestal Tripping

Reply #10 – July 23, 2025, 11:09:11 pm

Quote from: turbojack – July 22, 2025, 10:48:10 pm

This Gcfi 30 amp receptacle was either installed when the NEC required, insurance required, or inspector required it.

This is in a Quebec National Park. I assume they installed it because their codes require it, but I don't know for sure. The entire electrical install is new as of this season.

Re: 30A GFCI on Pedestal Tripping

Reply #11 – July 23, 2025, 11:15:16 pm

Quote from: Barry & Cindy – July 23, 2025, 12:32:54 am

If you said the pedestal did not trip until coach main breaker was closed, would leave out the transfer switch as it would close as soon as coach power was present at the transfer switch.

I agree. Also, it trips when the coach main breaker is closed, even with all the other breakers pulled from the main panel and the main breaker pulled from the sub panel. That indicates to me that the problem is not in any of the branch circuits. Also, the generator should be out if the circuit when it is not running. That seems to leave the inverter, unless I am overlooking something.

Re: 30A GFCI on Pedestal Tripping

Reply #12 – July 24, 2025, 12:22:00 am

With all your diagnosis, problem has been isolated to main breaker panel. Inverter is out of the picture as it gets power off main breaker panel.

Look carefully to see if any green ground buss bar is wired to any white neutral buss bar. With power off like another said you could use a meter to check for continuity between neutral & ground buss bars in main breaker box. If this is all too much to do at this campground, if you have electricity somewhere else you could make a 20-amp test bed with an extension cord & store bought 20-amp GFCI, using 30-to-20 adapter, taking your time to open the main breaker and find the problem.

Pedestal GFCI trips when any amount of hot wire current is not exactly equal to current on neutral wire.

Another test could be to use a 30-to-20-amp adapter and see if the pedestal 20-amp GFCI trips. If not tripping use a long temporary extension and connect to another pedestal for a moment if you can.

Normally there are a lot of RV devices that could trip a GFCI, but you have all breakers off. And you have determined that your transfer switch does not trip GFCI when main breaker is off.

Your 30-to-50 amp adapter combines the RV power cord line-1 & 2 (red & black) hot wires to campground single black hot. Be interesting to remove one of the main breaker hot wires so when you close the main breaker you are only flowing current to one side of the main breaker, to see if one side or the other could be contributing to the trip.

How about closing the main breaker with downline breakers open, before closing the pedestal 30-amp breaker. Assume this was your original trip scenario.

Keep in touch

Re: 30A GFCI on Pedestal Tripping

Reply #13 – July 24, 2025, 02:49:09 am

There is a possibility that since the system is new that the breaker is bad. You need to verify that there is no continuity between the neutral and ground wires. First test at the 50 amp plug, I would also test your dog bone to verify that it does not have the neutral and ground together.

Re: 30A GFCI on Pedestal Tripping

Reply #14 – July 24, 2025, 06:48:34 am

Why not get in touch with Mike Sokol, he is an authority on most things electric(especially RV's and campground electric problems) and has a daily blog. This might be something he might like to expound on his website.

Re: 30A GFCI on Pedestal Tripping

Reply #15 – July 24, 2025, 09:22:39 am

Quote from: turbojack – July 24, 2025, 02:49:09 am

There is a possibility that since the system is new that the breaker is bad. You need to verify that there is no continuity between the neutral and ground wires. First test at the 50 amp plug, I would also test your dog bone to verify that it does not have the neutral and ground together.

yep, new definitely doesn't guarantee that it's good.

Re: 30A GFCI on Pedestal Tripping

Reply #16 – July 24, 2025, 10:08:21 am

Quote from: turbojack – July 24, 2025, 02:49:09 am

There is a possibility that since the system is new that the breaker is bad. You need to verify that there is no continuity between the neutral and ground wires. First test at the 50 amp plug, I would also test your dog bone to verify that it does not have the neutral and ground together.

I tried hooking up to the 110 GFCI on the pedestal using an adapter, snd it tripped as well. That seems to indicate the ground fault breaker is not the issue. I also checked continuity on the 50A plug and the 30 to 50 adapter and found no problems. The fact the breaker doesn't trip until the transfer switch kicks in also indicates the problem is not with the plug/cord or the adapter.

Re: 30A GFCI on Pedestal Tripping

Reply #17 – July 24, 2025, 10:16:05 am

Quote from: Barry & Cindy – July 24, 2025, 12:22:00 am

How about closing the main breaker with downline breakers open, before closing the pedestal 30-amp breaker. Assume this was your original trip scenario.

I tried it in that order as well and the result was the same. I also visually checked for wires connecting the neutral and ground in both breaker boxes and didn't find any. The one thing I didn't do was check for continuity between the neutral and ground. I will have to do that whenever I get the boxes opened up again.

One question I have is whether opening the breaker for the inverter, or even pulling it like I did, necessarily eliminates the inverter. If the neutral and ground are bonded through the inverter, wouldn't that connection remain even if the power going to the inverter is removed? The breaker only affects the hot leg; it doesn't change how the neutral and ground are connected.

Re: 30A GFCI on Pedestal Tripping

Reply #18 – July 24, 2025, 11:36:55 am

It is possible that the inverter has neutral and ground connected and backfeed to the panel. If you disconnect the neutral wire in your main panel it would eliminate the inverter.

Just to verify pedestal is wired correctly, do you have a toaster or other high wattage appliance that you can plug into the 20amp plug on the pedestal. If that works, then we can eliminate pedestal as the problem

Re: 30A GFCI on Pedestal Tripping

Reply #19 – July 24, 2025, 11:45:12 am

Quote from: dbennett9 – July 24, 2025, 10:16:05 am

One question I have is whether opening the breaker for the inverter, or even pulling it like I did, necessarily eliminates the inverter. If the neutral and ground are bonded through the inverter, wouldn't that connection remain even if the power going to the inverter is removed? The breaker only affects the hot leg; it doesn't change how the neutral and ground are connected

Pulling the breaker does not eliminate the inverter as the problem. Removing the hot and white wire from the panel will remove the inverter complete from the system. The inverter should only be combining the neutral and ground when it is inverting on the load side. The line side should stay separate.

Re: 30A GFCI on Pedestal Tripping

Reply #20 – July 24, 2025, 04:22:44 pm

Quote from: dbennett9 – July 22, 2025, 03:43:06 pm

I am at a campground that has a GFCI on the 30A circuit (no 50A). The GFCi trips as soon as the transfer switch on the coach kicks in. I have run into this problem a couple times before. I tried narrowing down the problem by first turning off all of the 110 breakers. The ground fault trips as soon as I turn on the main breaker, even with all the other breakers off. Just to be certain, I pulled all the breakers from the main panel except the main, and pulled the main breaker from the secondary panel, and it still trips as soon as I turn on the main breaker in the coach and the transfer switch engages. I have enough solar to get by with everything but the air conditioning, but I would like to figure out what is causing the problem.

I would start by making sure the neutral ang ground is not bonded in that main panel. There may be a misconnection on one of the branch circuits or even in an appliance. Having the breakers off will not isolate a downstream ground-neutral connection. There could also be a wiring failure in the rig. The inverter bypass relay could also be cause of fault. It would need to have the ground and neutral disconnected to isolate.

Re: 30A GFCI on Pedestal Tripping

Reply #21 – July 24, 2025, 04:28:27 pm

Have you done a reset on the Prosine?

Re: 30A GFCI on Pedestal Tripping

Reply #22 – July 24, 2025, 05:46:29 pm

This is a good read on the topic: https://www.rvtravel.com/rv-electricity-what-is-a-gfci-nuisance-trip/

Quote from: snip

What's a GFCI nuisance trip?

Well, let's define a "nuisance trip" first. Note that a GFCI (Ground Fault Circuit Interrupter) is there to monitor ground fault currents, and will trip off the power if the leakage exceeds 5mA (that's 5 milliamps or 0.005 amps) of current. And, of course, that's what shuts off the power. But most people don't understand that the leakage currents of ALL of the appliances in your RV add together.

Re: 30A GFCI on Pedestal Tripping

Reply #23 – July 24, 2025, 09:26:56 pm

Quote from: turbojack – July 24, 2025, 11:36:55 am

It is possible that the inverter has neutral and ground connected and backfeed to the panel. If you disconnect the neutral wire in your main panel it would eliminate the inverter.

Just to verify pedestal is wired correctly, do you have a toaster or other high wattage appliance that you can plug into the 20amp plug on the pedestal. If that works, then we can eliminate pedestal as the problem

The campground sent someone out to check the pedestal. He checked it over and tested it with a circular saw. It didn't trip.

Re: 30A GFCI on Pedestal Tripping

Reply #24 – July 24, 2025, 09:30:10 pm

Quote from: erniee – July 24, 2025, 04:28:27 pm

Have you done a reset on the Prosine?

What sort of reset do you mean? I have turned it on and off at the inverter, but nothing beyond that.

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