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Hi out there! I'm looking for some help from Freddie Kilowatt!! Bought a new (new to me)5er. Brought it home a couple of weeks ago. Plugged it into 30 Amp outlets while on the road, used the 110VAC outlets for charging flashlights , laptops etc. all's well. Come home and plug it into my 15 amp GFI in the garage and it trips the GFI every time, even with everything turned off. No blown fuses in the inverter cabinet, battery is a new marine deep cycle. Checked the breaker in the water heater. How do I go about looking for a short on the 110 circuit of the trailer. Today I started removing all of the outlets to see if there was anything behind the wall that would contribute, found nothing apparent. How do I approach this? Mechanical stuff I can work thru, this stuff baffles and scares me!! Thanx for any input.
 
GFCI's detect minute differences in the power going out the hot wire and the power coming in the neutral. When everything is working properly, the power going out will me virtually identical to the power coming back. If something "bleeds off" some of that power to ground, it will cause it to trip.

Try turning off every breaker in the panel and see if it happens. If not, turn them back on one by one till it trips.
If you have a removable power cord (plug in the side of the trailer that the cord plugs in to) try plugging that only in to the outlet.

Is there a chance you have any moisture in any of the outlets? Plugging in an extension cord that is wet is enough to trip a gfi.

Have you tried plugging in a drill or hair dryer to the outlet? Some outlets just flat fail and trip for no reason.

Place to start and we can go from there.
 
Thanx guy's you've given me some order to the madness. I'll start simple and work toward the trailer as you have suggested. Stay tuned!!BBBZZZZZZZZZ Yeow!
 
409, it sounds like your neutral is bonded on the trailer. If it were me, I would do like ckelley1 suggested and install a standard breaker. I'm an electrician and have seen similar setups in the past. Look in the panel in the trailer and see if the white wire is hooked up to the green or hooked by jumper or bonding screw. And, if you have a volt meter with a continuity tester, (ohms) then go from the white wire to the green or metal of the panel or frame. If it buzzes or shows a low ohm reading, then that is what's tripping your GFCI. The white wire (neutral) cannot touch steel or green wire or the GFCI will not work. A regular breaker will, however, work fine.
 
Thanks Cole and Powder! It's a 07 Sabre 33ft. Most everything appears to be in good shape, but I will look at the details. Had a 04 Cougar previous, it ran fine on the 20amp GFI Circuit, except for when the AC kicked on. Got used to what could run and what couldn't during load/unload chores.
 
409, it sounds like your neutral is bonded on the trailer. If it were me, I would do like ckelley1 suggested and install a standard breaker. I'm an electrician and have seen similar setups in the past. Look in the panel in the trailer and see if the white wire is hooked up to the green or hooked by jumper or bonding screw.
Good call. If the trailer has a generator then it can be bonded there. You'd have to look up the generator specs since it might be internal.
 
Good call. If the trailer has a generator then it can be bonded there. You'd have to look up the generator specs since it might be internal.

It should be bonded on the generator side of the transfer switch so that the neutral-ground bond is only effective when the generator is running since the RV's power distribution panel is the main panel in that application. When the transfer switch is on shore power, neutral should not be bonded to ground at the RV's power distribution panel since it is not the main panel - rather, the house power distribution panel that feeds the 15 amp GFI outlet in the garage should be where the neutral-ground bond is made, unless that outlet is fed by a sub-panel.

If all your outside outlets are dry, concentrate on the water heater's electric heating element, the power converter and (if equipped) inverter circuits in the RV. Some of these will drive a GFCI crazy.

Rusty
 
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One last thought... if you have a converter that changes 120 VAC to 12VDC to charge the batteries.... mine is a max 60 amp charge unit that tapers off.... 60 amp DC is at least 6-10 amps AC... this draw could put you over the limit with the other times that are on.... and thus trip the 15 amp circuit.... I know my trailer won't work on that... but it will run with minimum items on a 20 amp circuit...
 
Well! I isolated the circuit to the WH. The WH is dual/gas-electric. I took the leads off of the element and it still tripped! So I suspect as you earlier suggested either the GFI is weak (although it powers my battery charger etc.) or the GFI is popping because of the charger in the inverter. I bought a brand new marine battery as the original was bad, and have not heard the inverter fan since. I'm taking it to a local RV Service shop in the morning to get on a 30 Amp circuit and find out what is happening???? dazed & confused!! Thanx for everyone's input, I'll let you know the outcome regardless if obscure or obvious!? :)
 
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