GFI tripping.

[xjfam]

Here is the deal. I am working on the shore power for a boat at a residence, and when the 120 volt is landed in the panel (square-d) it trips the gfi at the house. If i lift the wires from the panel it holds. I took the old panel out thinking there was a problem with it and replaced it with the square-d panel. Nothing changed. None of the circuits are landed. Just the main power.
Any ideas.

 

[tom baker]

this GFCI is not feeding the boat power, right? Are there shared neutrals?

 

[brian john]

Conductor length?
Have you megged the conductors?
Does this happen with just the conductors landed, no loads or any other components connected?

 

[guschash]

More information. Is this a subpanel, that you are feeding with GFIC 120 breaker? Are you landing the ground and neutral on the same terminals in this panel?