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jagcb750 · 06-18-2008, 07:33 AM

Last year I wired the rear a/c unit to a plug in through a knife-switch style box. This allows me to run a plug-in through it and run both a/c units at the same time when on land power, not just the generator. It works fine at the house like this. When I go camping at a place that has 30 amp service, the plug-in for the rear air throws the gfi switch immediately when I plug it in. What's up with this? This has happened at three places I went camping: KOA, Baileyton rv park, and HollyBay Marina. Works fine plugged in at home. Do you think I may have the polarity reversed from the knife-switch through the plug-in? Would that do it?

Excella CM · 06-18-2008, 08:02 AM

GFCI works by monitoring the amount of electricity going out in the circuit tothat coming back from the circuit. Any discrepancy indicates a "leak" of some kind and will trip the breaker. I assume you're not running a GFCI at home? If you're mis-wired or have a ground problem or short somewhere that can do it. An appliance can work ok and still trip the GFCI, but if it does so, that indicates a problem that should be addressed.

Aage · 06-18-2008, 09:05 AM

Personally, before I blamed the GFI, I would get out a VTVM and one of those simple plug-in polarity checkers and have a look around at the mods I made.

richinny · 06-18-2008, 09:10 AM

http://www.airforums.com/forums/212338-post1.html

that thread might have your answer. you might want to read the last 10 or so posts first.

nodpete · 06-18-2008, 10:09 AM

There probably isn't anything wrong with your wiring set-up. If both AC units are on at the same time, whenever both compressors try to run at the same time, the amperage is just to high. When a compressor ( or any motor starts), it draws 3 times the rated run amps. GFI's are not made to protect equipment, they are to protect people. Change the breaker to a regular one and it should work.

jagcb750 · 06-25-2008, 11:44 AM

Thanks for the replies. What I thought was so strange was that when I plugged in the rear a/c to the gfi switch at the campgrounds, it would immediately throw the switch. The a/c was not even on at the time. just plugging it in with it off would make it throw. Strange, eh?

myfirstrv · 06-25-2008, 12:18 PM

I would say your Ground is getting current, either from the way you wired it, or back feeding from antother source

garry · 06-25-2008, 05:05 PM

It is my understanding at the generator the ground & neutrals are tied together and this causes the GFCI to trip. This is a normal configuration and not sure how you can get around it.

Ground and neutral should only be connected at the "main" campground breaker panel same as in your house wiring.

Garry

edit to add quotes"

bkahler · 06-26-2008, 01:35 PM

Quote:

Originally Posted by garry

It is my understanding at the generator the ground & neutrals are tied together and this causes the GFCI to trip. This is a normal configuration and not sure how you can get around it.

On our 310 I believe the ground and neutral are tied together, however there is an isolation relay that disconnects the neutral side of the generator from the coach side wiring. If the generator is not running the isolation relay is de-energized and the generator neutral is isolated from the coach. When the generator starts the isolation relay energizes and provides power to the coach. At this time the ground and neutral on the coach are tied together. There is another isolation relay at the main entrance panel to the coach that also energizes when the generator is running which isolates the coach from shore power all together.

Quote:

Ground and neutral should only be connected at the "main" campground breaker panel same as in your house wiring.

Agreed. Same as your house wiring, ground and neutral are only connected in your entrance panel, no where else.

Brad