Well… since you cracked open the lid to Pandora’s Box I might as well open it all the way.  I know this thread started with a simple question and now I have made it into a complex issue.  If I did not think it is important I would not have taken the time to respond. Mike and I agree on how to connect shore power to a RV, or in this case a truck being modified for inclusion of 120 VAC shore power. But, we do not agree on how to wire in an inverter or generator.  Mike’s answer complies w