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 herehttps://www.dropbox.com/s/l1aadigxn7gwqps/Trailer%20Wiring.jpg?dl=0

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.

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.

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.

Ok, that makes sense. To put it before the one breaker, I would have to do a sub panel? There is not a way to put it before a single breaker in the existing panel, correct?

This is what I did with mine. GFCI is the breaker for my outlets. K2 is the relay I added.

Inverter and Auto Transfer Switch | Good Sam Community

2oldman
Explorer II
May 07, 2019
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.
helix528
Explorer
May 07, 2019
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.
2oldman
Explorer II
May 07, 2019
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.
helix528
Explorer
May 07, 2019
Ok, that makes sense. To put it before the one breaker, I would have to do a sub panel? There is not a way to put it before a single breaker in the existing panel, correct?
Tom_M1
Explorer
May 07, 2019
This is what I did with mine. GFCI is the breaker for my outlets. K2 is the relay I added.
opnspaces
Navigator II
May 07, 2019
helix528 wrote:
Ok, that makes sense. To put it before the one breaker, I would have to do a sub panel? There is not a way to put it before a single breaker in the existing panel, correct?

Correct, you would need a separate sub panel to run one breaker.
hedge
Explorer
May 07, 2019
hmm, I ran mine just how you outlined... I didn't even think of the breaker. Now you have me wondering if this is ok.

I would think the breaker would protect it when it is the power source and the inverter overload would protect it when running from the inverter wouldn't it?
Just_There
Explorer
May 07, 2019
I am planning on a similar scenario. My latest idea:
Use an inverter with automatic passthrough switching, move the outlets to the output of the inverter, wire the AC input of the inverter to the now empty breaker. I would count on the internal breaker of the inverter to protect the outlets/wiring. Your outlets will always be hot unless you shut down the inverter.
Just_There
Explorer
May 07, 2019
helix528, what load/inverter size are you planning?
wa8yxm
Explorer III
May 07, 2019
I will make it as easy as possible

Instead of an "inverter" get an "Inverter/Charger" A suggestion is somethign like the Xantrex Freedom XC-2000 I will give you the counter on that specific in a bit.

It hooks up like this

Main panel--30 amp branch----Freedom XC---Sub panel--TV, MICROWAVE, GFCI or other outlets) Each circuit has itss own Sub Panel Breaker

Notes:
A Sub panel DOES NOT HAVE Neutral and Ground bonded (Neither should an RV's main that is done at the park end of thigns)

Second: On my Freedom XC I really DO NOT LIKE the way the 120 volt wires connect I broke some of the connectors and had to use "other means" to hook it up.
(Thankfully that's not a problem for me).

THe charger on the Freedom. Is programmable

Before that I had a Prosine 2.0 (Basically the same thing. wired the same way but I like the connections way way way better)

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