GFI keeps popping

[solo pilot]

While trying to install anew boondocker inverter/charger have tried to hook up shore power. Last week had lights this week the GFI keeps popping. Have unplugged everything and have made sure AC is off. The 12 volt system is completely unhooked. Have I missed a ground somewhere. Any help is welcome.

[TheGreatleys]

Do you have the 120v neutral hooked to a ground at any point inside the trailer?

[solo pilot]

Installed new outlet for charger using existing wire. Try disconnect bare ground?

[Wayne&Sam]

Are you referring to a GFI your umbilical is plugged into or a GFI in the Airstream?

[A W Warn]

Originally Posted by solo pilot

Installed new outlet for charger using existing wire. Try disconnect bare ground?

Did you reinstall the wires with correct polarity. Black wire should go on the brass colored screw and white wire should go on the silver colored screw. It's easy to reverse them. (it seems like you are saying you installed a new receptacle where there was an old one, using the existing wire).

[ijustlee]

GFI's measure the electricity going through both the hot and neutral wires and if all the electrons that went out through the hot don't come back through the neutral they trip. Look for anyplace that the electrons can be diverted from their appointed rounds. A neutral to ground connection can cause just as big a problem as a hot to ground connection. A digital Ohm Meter is really helpful. It can really help to draw the circuit with all connections onto a piece of paper if you don't have a schematic.

[A W Warn]

One other thing I just remembered; on a 1970's model trailer I owned several years ago some previous owner had rewired and added a bonding screw in the breaker box. You might check to make sure the neutrals and grounds are not bonded in any way. I'm speaking only of the 120v system:
(1. Make sure the white and bare copper wires are not connected into the same bar inside the breaker box) There should be a separate bar for neutral (white wires) and a separate bar for ground wires (bare copper or green).
and
(2.Make sure that the neutral bar is isolated/insulated from the breaker box. The neutral bar's mounts should have some non-conducting material separating it from the metal breaker box and also separating it from the mounting screws that fasten it to that box.)

[TomS]

Has your outside outlet gotten wet lately? That caused ours to trip...

[HiJoeSilver]

Originally Posted by solo pilot

Installed new outlet for charger using existing wire. Try disconnect bare ground?

So you installed a gfci outlet specifically for the converter, if I read this correctly.

Other than its normal purpose the ground wire doesn't have any additional purpose in a gfci. A gfci simply looks for a difference in current between hot and neutral. It can take as little of an imbalance of 5 mA to trip. Converters usually have good size capacitive circuits so as the capacitor charges it causes a current imbalance betwee inlet and outlet of the inverter because some of the charge is being stored in the capacitor. Easily enough to trip a gfci outlet.

One other common cause is wiring the hot supply and load wires backward. If the gfci has more outlets downstream they're both black so it's easy to swap during install. See professional electricians do it regularly.

[solo pilot]

Thanks to all. Polarity seems to be the overall concern. Next day off will check all points mentioned.