Many SMB owners have had problems with external GFI's tripping while plugging into shore power.
John (John & Dana)
found a solution to keep the GFI from tripping when plugging in the van to the AC power source. (Note) This seems to be a problem with the Tripplite inverter SMB has offered. Newer Tripplite or other brand inverters might not have the same problem.
Here is the trick to plug into a GFCI if you have the Tripp-Lite inverter/charger. Turn the inverter on (auto invert) and then plug to the outlet. After waiting a couple of minutes you can turn the inverter off (line charge only) and you should be fine. You could also leave the inverter in the on and the batteries will charge just fine.
I hope this helps.
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