Electrical blowing house ground fault

[Swampy]

Originally Posted by SueRoeske

We plug in our No Bo 19.5 to our house 20 amp to get refrigerator cooled for the next trip. Tonight the ground fault is blowing every time we plug in the No Bo. This has not happened before.

Nothing is on in the camper, we have not turned the refrig on yet.

We checked our house circuit breaker and reset each. No difference
We used a different extension cord from camper to house. No difference

What else could be causing this?

SueRoeske,
It does not take much conductivity to trip a GFCI. I would start by turning off everything (all the breakers ) in the TT, then turn on main and the one feeding the refrigerator. this should isolate the circuit with the offending ground path. You need to open any outlets on the outside of the TT and make sure there are no spider webs , dirt, or moisture ... any or all will cause a GFCI to trip if there is a hot to ground electrical path. If asll else fails, unplug your refrigerator from the internal TT outlet and plug it into the extension cord, directly. If the GFCI in your house still trips, then just plug the extension cord into a non GFCI outlet inside. The circuit breaker will protect from any overloads, but you could have a problem with the 120V electrical in the fridge. it could have an electrical current leak to ground that could cause it to have a "hot skin" condition. So make sure you wear shoes and don't stand in water while touching the fridge. Or touch the fridge and another 120 volt appliance at the same time.
I hope that helps you enjoy your trip. BTW the advice you received from your ME acquaintance is not correct. I'm an EE and electrician (retired)... Swampy

[KyDan]

Swampy,, you might be right BUT.... many of us have found that plugging a RV with a GF breaker/outlet into a supply with another GF breaker just won't work.
Some GF outlets just don't play well with another one in the mix.
We should all be careful but telling those folks not to touch their appliances is a bit much IMO.....
Now if they said they felt a "tingle" when they touched their rig like some have posted here-- I'd be all over that with extra caution and something is definitely wrong there!

[Swampy]

Originally Posted by KyDan

Swampy,, you might be right BUT.... many of us have found that plugging a RV with a GF breaker/outlet into a supply with another GF breaker just won't work.
Some GF outlets just don't play well with another one in the mix.
We should all be careful but telling those folks not to touch their appliances is a bit much IMO.....
Now if they said they felt a "tingle" when they touched their rig like some have posted here-- I'd be all over that with extra caution and something is definitely wrong there!

I concur that a series of GFCI devices will likely cause nuisance trips. If she had already isolated the 120V section of the fridge and it still tripped the GFCI, then the fridge is the suspect equipment with the leakage current. I am assuming she has plugged the extension cord into a non-GFCI protected source and she does not have a non-contact voltage sensor.The TT would not be plugged in, so not a part in the circuit, except the ground and grounded conductors which include the chasis of the TT. Thus if the fridge is the leakage source, there could be as much as a 120V "tingle" between the isolated fridge and the other appliances. That could be a rather severe "tingle", maybe even fatal. If the TT is in a "hot skin" situation, this would connect the leakage from the fridge chasis to the TT chasis with the TT not even plugged in.
The worst case I have encountered in a residence was caused by a heating element in a water heater that was still working, but had internal leakages through the heater element which energized the plumbing to nearly 230V and ultimately caused the telephone and CATV to burn off their grounds at the service entrance and melt the siding. That takes some "tingle" to burn a #6 copper wire in half! Just think what could have happened to the homeowner if his telephone and CATV hadn't started acting up. Sometimes that tingle may be fatal.......... Swampy

[KyDan]

In your 1st paragraph you "assumed" something you do not know for a fact.
In the 2nd you veer off to tell a horror story involving a residential issue.
Now I'm scared to touch my rig without rubber gloves.....

[Swampy]

Originally Posted by KyDan

In your 1st paragraph you "assumed" something you do not know for a fact.
In the 2nd you veer off to tell a horror story involving a residential issue.
Now I'm scared to touch my rig without rubber gloves.....

KyDan,

I have experienced many weird electrical phenomena over the years, and have performed forensic studies on several electrical contact fatalities. The scariest I ever encountered was a condition called ferroresonance. I was switching off line a 34.5kV 3-phase transformer overnight at a marina and isolating the HV connectors on the end of a 10 foot fiberglass hotstick. The high voltage from the ferroresonance condition caused the corona to travel about 3 feet up the hotstick toward my hands. I was fearful that even my class 4 gloves wouldn't be enough for that, nothing behind me but water, but I managed to park the hot cable and the glow extinguished. I later calculated the resonating voltage to be near 100kV.
So what does that have to do with a potential hotskin on a TT? Well, you should always test before you touch. (So without a tester your rubber gloves are a good idea! I recommend at least a class 0.) I am a firm believer in non-contact voltage testers. They are little battery operated devices about the size of a fat ballpoint pen that will beep and flash when in the presence of an electrical field. I always test my TT after plugging into the power pedestal at the CG. You may never know what electrical component has vibrated loose on the trip there. And as it is, I have a hard enough time just getting DW to go camping, much less without worrying about electrocuting her! ... Swampy