A ground buster would be one way to check for excessive leakage to
ground. But exercise caution: the GFI is tripping either because it is
defective or because there is a potentially dangerous leakage. We tend
to immediately suspect a more or less constant borderline leakage such
as might occur in the case of a defective or poorly designed filter as
Larry suggests. Or it could be a less-likely but very serious
intermittent condition like a short. If so, with a ground buster in the
circuit, your body could well supply the leakage path to ground.

But most of the chargers use 2-wire, "polarized" ac cords in which case
the ground buster would have no effect. With a 2-wire cord and a
properly functioning GFI and nothing else plugged into the receptacle or
the computer, a trip can occur only if you provide the path to ground.
If it trips while you are not touching it and it is fully insulated from
the boat's ac ground, the GFI is probably defective.

You still haven't told us if your GFI is a breaker type in the main
panel or a receptacle. If the latter, why not just plug the computer
into one of the other protected outlets on the boat? If the former,
complex grounding or wiring situations could cause the problem.

Good luck.

Chuck

Larry wrote:
If it has 3-wire grounded plug on it, plug it into a ground buster and see
if it stops. The input filters on some of the switching supplies allows
enough AC to ground pin to trip them. I've had some ground loops trip mine
here at home from certain printers plugged into the outlets on other
circuits than what the computer is plugged into.

"johnhh" wrote in
:


All of my 110 outlets on the boat are protected through GFI. Whenever
I plug my laptop charger in or turn on the computer with it plugged
in, it trips the GFI. If I reset it a time or two or three, it will
hold and work fine until the next time. Interestingly, it will even
trip the GFI on a parallel circuit. I am guessing that it has
something to do with the large capacitor in the charging unit charging
up. Does anyone have an explanation and/or solution?

thanks
john