[C320-list] Shore power system

[Ron Squires]

This is our first season with this boat. When we connect to the shore power supply we encounter two problems, so far. First is we get a reverse current light, second when turning on the main AC breakers in order first the one at the inlet then the one the panel, the GFCI at the supply point trips.
What we have noted already while investigating is that the neutral bus and the safety ground bus are connected on the single shared terminal strip via what look to be original jumpers.
The boat does not have an isolation transformer.
I can't believe this boat has been miswired this long without someone questioning the buses being connected.
Can anyone think of a reason they would have, or should be connected on the early series boats(hull #26)?
The buses being connected does explain the GFCI trip but not the reverse current light. We have checked the source and cord with a polarity checker and they are OK.
We need to dig deeper into the AC system, will we find any more surprises with the system on a boat with an early hull number?

_/) Sent from my iPhone 5