Forum Discussion

duggram's avatar
duggram
Explorer
Sep 19, 2015

ATS (Automatic Transfer Switch) fried?

Last time out with the fifthwheel I saw a flash out of the corner of my eye when I had the basement door open coming from the vicinity of the ATS. Everything in the trailer kept working but I can't remember if I used anything that was 110 volt.

Today I bring the trailer home to work on it. I plugged the power cord with 50 amp surge suppressor in which then puts on its time delay light. After about 3 minutes the suppressor starts making a clicking sound and vibrates for about 10 seconds then stops. It pops the house breaker to the outside outlet which is the one I normally use with the trailer. When I plug in the trailer line without the suppressor and switch the house breaker on, it pops immediately.

I took the cover off of the ATS and I see nothing to indicate a flash has occurred inside of it or on the outside around it. Any suggestions on what I can check next? I don't want to buy a new ATS if I don't need it.

23 Replies

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  • D_E_Bishop's avatar
    D_E_Bishop
    Explorer
    Sep 21, 2015
    In your last post you stated that with the CB labeled GCA off and all others on the ATS hummed and yet you had no 120vac. I find that suspect. Do you have a DMM or a 120vac test light? If so have you tested the load side of the CB's? How many do you have?

    The GFCI would be on the load side of one of the breakers and shouldn't cut all power in your trailer. I would guess that the ATS is working if turning on the breaker labeled GCA trips the house breaker. If you have unplugged or turned off all 120vac powered items and you are still tripping the house breaker, you have a dead short on the load side of that breaker.

    This is why it is so important to label all your breakers, and to designate which breaker feeds the GFCI(s).
  • CA_Traveler's avatar
    CA_Traveler
    Explorer III
    Sep 21, 2015
    Well now you know the problem is downstream from the CB. Unplug all AC appliances like HW, refer, MW, etc and see if that helps to isolate the problem.

    GFCI's don't normally cause a short instead they open to kill downstream power from the GGCI.

    Do you really have 120V lights and ceiling fan? My RVs were 12V.
  • duggram's avatar
    duggram
    Explorer
    Sep 21, 2015
    Bobbo wrote:
    duggram wrote:
    Thanks for the quick replies. I was hooked up to a 15 amp 110 volt outlet

    This changes everything. If you have much stuff powered on, you will trip the 15 amp breaker at the house. The converter alone can pull half of that or more if the batteries are very low.

    If you re-read my first response above, I stated that you had problems if you were popping a 50 amp breaker at the house. I didn't know it was only a 15 amp breaker.

    Turn off EVERYTHING in the RV and try again.


    Thank you for your comment, however I've been using that 110 outlet at home with my trailer for more than 6 years now and I've never had a circuit breaker issue on that circuit. I understand how to safely use it.
  • duggram's avatar
    duggram
    Explorer
    Sep 20, 2015
    OK it's a trailer breaker labeled GCA. When it's off all other trailer breakers can be on and you can hear the TS humming. As soon as I turn that breaker on the house breaker turns off. Is this the breaker that the GCI outlet would be wired to? Is this also why nothing 110 works like the 110 lights, ceiling fan? Any suggestions on next move?
  • CA_Traveler's avatar
    CA_Traveler
    Explorer III
    Sep 20, 2015
    Bobbo wrote:
    duggram wrote:
    Thanks for the quick replies. I was hooked up to a 15 amp 110 volt outlet

    This changes everything. If you have much stuff powered on, you will trip the 15 amp breaker at the house. The converter alone can pull half of that or more if the batteries are very low.

    If you re-read my first response above, I stated that you had problems if you were popping a 50 amp breaker at the house. I didn't know it was only a 15 amp breaker.

    Turn off EVERYTHING in the RV and try again.
    X2 Turn off all rig CB's, plug in and if the house CB doesn't trip turn on the rig main CB followed by individual CBs one at a time to isolate the problem.
  • Bobbo's avatar
    Bobbo
    Explorer III
    Sep 20, 2015
    duggram wrote:
    Thanks for the quick replies. I was hooked up to a 15 amp 110 volt outlet

    This changes everything. If you have much stuff powered on, you will trip the 15 amp breaker at the house. The converter alone can pull half of that or more if the batteries are very low.

    If you re-read my first response above, I stated that you had problems if you were popping a 50 amp breaker at the house. I didn't know it was only a 15 amp breaker.

    Turn off EVERYTHING in the RV and try again.
  • time2roll's avatar
    time2roll
    Nomad
    Sep 20, 2015
    This might be going beyond what can be done via message.

    The 30/50 adapter will connect L1 & L2 and should not be connected during any tests.

    It is just a logic process to find the short between L1, L2 and N or G.

    Probably a junction box as the cord inlet connects to the romex that feeds to the TS. May as well pull it all apart and test.

    Then start putting it back together until something shorts. Disassembly and reassembly may fix the issue also.
  • duggram's avatar
    duggram
    Explorer
    Sep 20, 2015
    With the line from the TS to the RV breaker panel disconnected from the TS I have continuity between all three connections on the inbound (chord) side. When I disconnect the 30 amp adapter from the chord, I have no continuity between L1 to either L2 or L3. With the 30 amp adapter back on the chord, and with the 110 volt adapter removed I still have continuity between all connections.

    No signs of any burning on any thing.
  • time2roll's avatar
    time2roll
    Nomad
    Sep 20, 2015
    Indicates the cord is good. Now remove the TS to breaker panel romex from the TS. Do look again if any wires look crossed up, heated etc in the TS.

    Then check the cord again while connected to the RV.
  • wolfe10's avatar
    wolfe10
    Explorer
    Sep 20, 2015
    No, that does not indicate a problem.

    In your 30 amp male to 50 amp female, the single hot on the 30 amp end is connected to BOTH hots on the 50 amp end. Take off your adapter and verify this yourself.

    Said another way, the 30 amp end has ONE hot, one neutral and one ground. The 50 amp end has TWO hots (fed by the single hot on the 30 amp end), a neutral and a ground.

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