Originally Posted by Bama Rambler
I'm going out on a limb here and assuming you only have a converter.
I doubt that your problem is the 12v side I do believe from your last post it's at the converter. The converter is actually more than just a converter (I know, I'm confusing you again) it's a power center/converter. The 30amp shore power cord comes in there and is connected to a power distribution center (breaker panel) that feeds power to the 120volt side of the RV and to the converter. There are ground and neutral bars in the converter/power center housing and if one of the ground wires was put on the neutral bus or one of the neutral wires were put on the ground bus a regular breaker wouldn't care but a GFI would trip. Also, if there's current leakage in your converter from neutral to ground, that'll trip a GFI. Either of those scenarios would explain why the GFI didn't trip when you took the circuits loose from the power center and plugged them straight into the entension cord. If you hooked the converter up to the extension cord by itself without any other circuits being hooked up and it tripped the GFI I'd start looking for a shorted neutral/ground connection in there. If you can't find an obvious one then it's probably a shorted component and your choices are to either replace the unit or try and have that one repaired. Check out www.bestconverter.com
for some good info.
sorry, it is a converter that i have. i understand what you are saying about the crossed wires but i dont think i have that situation! when i purchased the trailer sept./09 the seller said the converter was over charging the onboard battery (17-18 volts instead of 14.5 in charge mode) so he purchased another new converter and installed it a few days later as part of the deal!( he was a very knowledgeable and technical guy) but the GFI popped with the old and new converter ( the seller had no idea what would cause this so we shook hands and he rode off into the sunset (ha). It now runs at 14.5 volts in charge mode!
I live in Canada so i was checking "outthere" to see which way i should approach this problem when the warmer weather begins because its too cold to work on it most days ( brrrrrrrrrrrr...) So i appreciate any suggestions anyone might have , thanks