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helix528's avatar
helix528
Explorer
May 07, 2019

Inverter and Auto Transfer Switch

I'm working on a project on my 5th wheel to add an Inverter, with a Auto Transfer Switch. I am trying to make it as automatic and fool proof as possible. I want to power just wall receptacles, and not AC, Micro, Water Heater, Fridge, power converter etc. I've seen some installations where the whole RV is powered by the inverter, and they just shut off breakers for the items they don't want drawing power. I want to avoid this scenario and keep it all automatic. So my idea is to feed power from the one breaker that controls the majority of the plugs. I would pull the romex that is currently on that breaker, and wire it to the output load of the transfer switch, then wire the breaker to the AC Input 1 on the transfer switch, and the input 2 would feed from the inverter. See the attached diagram.

My biggest concern, is with this method, when running on inverter power, the receptacles are not behind the breaker. They are only running through the breaker when on shore power. Is the internal protections of the inverter enough, or is what I've mapped out not going to work?

I cant get the wiring diagram jpg to work, but you can see it here
https://www.dropbox.com/s/l1aadigxn7gwqps/Trailer%20Wiring.jpg?dl=0

13 Replies

  • helix528 wrote:
    Put it before all the breakers?

    Just not sure if Inverted power is typically behind a breaker, or if it needs to be.
    No, I meant just the one breaker.

    Inverted power always goes before the panel for whole-house installations, or sub-panel installations, which are not easy.

    I'm sure you'd be ok with your original plan, but down the road you may get more batteries and wish to run your microwave. Then you have to do this all over again.
  • Put it before all the breakers? I want to avoid doing that, or I will have to manually shut off breakers every time it swaps to inverted power and back on when on shore power.

    I don't think I could wire it before the one breaker, unless I did a sub distribution box and ran power from the main box, to the secondary box, and put the switch between the main and secondary boxes. Trying to avoid that complication.

    Just not sure if Inverted power is typically behind a breaker, or if it needs to be.
  • Could you move the xfer switch to *before* the ac breaker? That's usually how it's done.

    For some reason newbies don't get to post links.

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