Another consideration, and it likely doesn't apply to the OP nor most TC'ers, but I mention it just in case there are folks that does apply to, is ferry crossings. Our ferry is only an hour and a half-ish and you must turn off your propane. I just leave the fridge off as it stays cold just fine for that length of time. But if you have a multi hour crossing, it might need consideration, like so Euro ferries.

 

That's the way that the Lance dealers do it using a #8 wire from the socket directly to the battery thru a 40 amp circuit breaker.