Aaron,

You overestimate the cost and complexity of a DIY auto transfer switch.
Here's a first-look relay for $18.49:
http://www.mouser.com/ProductDetail/TE-Connectivity-PB/T92S7D22-110/?qs=sGAEpiMZZMtSzCF3XBhmW6vMa%2fMpJxoP71VMV4XEUfE%3d

Only one relay is needed if you only want to transfer between shore and
generator -- just delete all the connections and components in the Inverter
section.

But if you're not comfortable with that level of electrical fabrication,
stick with the factory-built solution. But remember that with your
isolated ground system, you shouldn't need a 50A switch. I believe you'll
find that all commercial transfer switches operate just about like my
diagram, meaning that the shore power will never see the Onan's combined
Neutral and Ground connection.

HTH,

Ken H


On Fri, Sep 1, 2017 at 9:29 PM, Aaron Bush wrote:

> Ken Henderson wrote on Fri, 01 September 2017 15:36
>> Aaron,
>>
>> I'm with Rick; your solution needn't be too complicated; the Coachmen
>> should have had separated Neutral and Ground busses.
>
>
> That's correct - my busses are separate at all boxes on my coach - the
> ground and neutral are only connected at the generator and that neutral is
> not
> switched anywhere, nor is the ground from the generator. The comment about
> the neutral and ground busses being connected was not mine, and it's not
> actually the problem that I have. I guess the *simplest* thing for me to
> do would be to put in a double pole breaker at the main generator box - but
> that still leaves a convoluted set-up with more boxes, more wire, and
> certainly more junction boxes and wire nuts, than I actually need. Also, if
> I
> get rid of the excess boxes and wire I will gain some usable storage
> space. Also doesn't resolve power for my 2nd AC on shore power. So toss that
> idea.
>
>
> Quote:
>> As for the switching, I'm not sure ordinary 50A Automatic Transfer
> Switches
>> will recognize the 30A plugs you intend to use. Further, there
> complexity
>> and cost are not justified. Here's DIY version of a 30A transfer I've
>> used, without attention, for the past 19 years:
>>
>> http://www.gmcmhphotos.com/photos/g3484-automatic-120-
> vac-power-source-selection.html
>>
>> It's simply wired; in fact, mine's in excess space inside my replaced
>> circuit breaker panel (that's probably not Kosher, 'tho').
>
>
> Mmmmm, this seems a bit complicated to me. It's certainly a little more
> than I'm easily comfortable with in terms of electrical diagrams - but it
> looks like I would need two of the power relays ($50 each), two diodes(14
> cents each), and two capacitors (don't know the price.) That puts me at
> around before the capacitors $100, about $50 less than the switch I am
> looking at. Basically you built your own automatic transfer switch correct?
> It
> might be worth $50 of my money right now to pay some one else to build it
> for me. I would probably enjoy doing that if I had a little more time for
> it.
>
> I'll double check on whether the PD52 transfer switch will work with 30
> amps - I believe it will, but the connection instructions for that switch
> are
> not entirely clear.
>
>