Issues such as this caused be to quit my electrical engineering education and switch to mechanical engineering...
I received delivery of a 1969 AS Sovereign
trailer the other day. It is currently sitting on a plot of land without available shore power. It has a 30 AMP voltage center installed (Parallax Power Supply 5300 series power converter) with a standard round 30AMP type plug input.
I can power it with no problem off of a portable generator. I have an adaptor that I use to convert the 30AMP round plug to a standard 15AMP plug. I plug it into the generator and everything works well.
I use the same setup to plug my Airstream Interstate into 15AMP shore power when I'm at home.
Seeing that I don't want to constantly run the generator to power the trailer, I figured that I would try to power it from my Interstate (I have a fair amount of battery storage and a rocking solar system). When I initially plugged the cord into the Interstate outlet, I immediately tripped the Interstate's GFCI outlet. I figured the trailer load was too high, so I shut everything down in the trailer and tried it again. Same result. I thought maybe it was a wiring issue with the trailer, so I just plugged in the 15AMP side with the 30AMP side disconnected. Same thing. The GFCI trips immediately without any load present. Seems like it is wiring issue, however the wire setup works fine when powered by the generator.
Being that it was dark and cold while I was doing this, I just fired up the generator and plugged into it without issue. We left the next day and I didn't get a chance to troubleshoot any further.
The Airstream has a Magnum MMS1012 inverter and runs all of the AC in the Interstate without issue.
My guess is that the problem has to do something with the power cord or 30-15AMP adapter. Something that the generator doesn't mind, but the GFIC is sensitive to.
I head back down this weekend with the Interstate and will trouble shoot some more. In the meantime, anyone have any suggestions?