--It is a GFI receptacle, not a breaker.
--The charger (110AC to 18.5v DC) has a 3 wire plug.
--It only occurs with the laptop and always occurs with the laptop
--It makes no difference what else is connected to the laptop or AC.
--It occurs whenever the computer is turned on or the charger is plugged
into an already running computer.
--It always recovers after one to three resets.
--It is far too consistent to be an intermittent condition like a short.
--It usually, but not always, trips both the GFI it is plugged into and the
other one on a parallel circuit.
--I have two different AC circuits off of the same breaker but each
protected by a GFI outlet. I am not sure of the exact wiring of these as I
haven't traced the wires down.

--No matter how much information I think I give or imply, I always seem to
leave something out.

--I'll try it on the second GFI on the boat, but will be very surprised if
it works there.
--I'll bring it to the house at the next opportunity and try it there.
--I'll try a ground buster.

I am of the belief that there is really nothing wrong with anything.
Larry's induced current theory sounds reasonable. These chargers have a
very large capacitance that take a second or so to charge up. I believe it
has to do with that charging somehow.



"chuck" wrote in message
news
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