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astraelraen's avatar
astraelraen
Explorer
Aug 11, 2014

RV electrical

We just built a new house and I had a 20amp breaker put in. Went with a 20amp because the electrician said that should run 95% of RV's just fine, including AC... hindsight tells me I should have gone with a 30amp, but that's done and gone at this point.

My 20 amp outlet has GFI on it and the RV trips the GFI every time it is plugged in. My old house had a 15 amp outlet with GFI and the RV would at least plug in without tripping GFI.

I calld the electrician who wired the house and he mentioned maybe the GFI was "extra sensitive." In my old house the GFI outlet was only about 5 years old, so I would guess they would be of similar "sensitivity."

I tried a variety of combinations of turning the different breakers off inside the RV and plugging the outlet into the wall.

There are six breakers, main, general #1, general #2, microwave, water heater, and A/C.

I could plug it in without tripping GFI by turning on any TWO breakers except for main & general #2. If main and general #2 were on in the RV, it would always trip GFI. This made me think general #2 has issues, but, any time I turned on any combination of three breakers the GFI would trip.

Any tips?

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  • time2roll's avatar
    time2roll
    Nomad
    Aug 11, 2014
    Remove the panel that covers the wires behind the breakers.
    Verify all grounds and neutrals are grouped on separate buses. Ground and neutral need to remain separated in the RV or you get a loop that will tend to trip GFCI.

    Next you may need to start disconnecting branch circuits. Eventually you need to separate and isolate to find the issue.
  • enblethen's avatar
    enblethen
    Nomad
    Aug 11, 2014
    Get one of these and test receptacle at the house. It could be wired incorrectly.
    Circuit tester
    If tester shows correct wiring at the house, it could be a bad element such as refer in the rig or a bad GFCI receptacle.
    Turn off all circuit breakers in the rig. Plug into shore power. Does it trip? If yes, then there is a connection between the neutral and ground in the rig. Again element or GFCI receptacle.
    If it does not trip, turn on main, then one branch circuit at a time. If one trips the GFCI it is on that circuit.
  • astraelraen's avatar
    astraelraen
    Explorer
    Aug 11, 2014
    I am not using an extension cord, it is close enough to make it with the RV cord & an adapter.

    I will try the fridge idea. I have done some general searching and it appears the fridge and water heater are two main culprits. The water heater is on it's own breaker and that breaker being on doesn't seem to cause any problems.

    The fridge does not appear to have it's own breaker though, maybe it is on general #2, which seems to have a problem...
  • RoyB's avatar
    RoyB
    Explorer II
    Aug 11, 2014
    How are you connecting to the house system.

    I am guessing you have a 20AMP 120VAC Receptacle maybe in the garage and then you are using an extension cord to get out close to the trailer. Then you plug into the extension cord using a RV30A-15A long DOGBONE type adapter (WALMART)...


    The extension cord should be no smaller than a 12GAUGE (12-3) but would be very good if you was using a 10-GAUGE (10-3) Extension cord. I am using two 50-foot extension cords coming from my garage and connecting to my POPUP and 5th wheel trailers.


    You must always use the LONG DOGBONE type adapter as the small round ones will get hot on you after just a few time of using them...
    DO NOT use these type of RV 30A-15A adapters


    This is what we do with our 15/20AMP Service receptacle out of our garage...

    Works great here with my OFF-ROAD 30AMP POPUP and also my 5th wheel on a different 15/20AMP circuit in the garage... I can run my 13,500 A/C and all the other items just fine. I do have be cautious on what I have on when I try to use a couple of heavy current items at the same time like the A/C and the Microwave etc. Otherwise it will trip my garage breaker.

    Roy Ken
  • pianotuna's avatar
    pianotuna
    Nomad III
    Aug 11, 2014
    Hi,

    A drill is not a very high wattage device. Use a hair dryer or heater.
  • ScottG's avatar
    ScottG
    Nomad
    Aug 11, 2014
    Get in the compartment behind the fridge and unplug it. If it doesn't trip the GFCI after that then the heater is failing and needs replacement.
  • astraelraen's avatar
    astraelraen
    Explorer
    Aug 11, 2014
    I will try a drill or something high watt this evening or tomorrow.

    The trailer was purchased used. I know the trailer wire that plugs into the tow vehicle was a little worn as I see obvious signs of electrical tape/cord repair. I did not investigate that further though as it seemed to operate fine. Maybe I will investigate the actual power cords and look for signs of wear.
  • westend's avatar
    westend
    Explorer
    Aug 11, 2014
    It sounds like your RV has a wiring issue, many times it can be as simple as the cord. Could you try plugging into the new 20 amp service, some higher watt devices and see if the GFCI trips. That should eliminate the GFCI and circuits in the house.

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