120V 20A yard GFCI trips?

GrandpaSteve

GrandpaSteve

Sustaining Member
Hello,

Boat is hauled for the winter. I was going to do some work aboard, and used an adapter to connect my shore power connector to the utility post at the yard (about 100' away). As soon as I turn my main breaker on my AC panel on, the GFCI trips on the utility post. Tried a couple of other utility posts with the same result.

I understand GFCI, and I understand that I have not made any AC modifications to my boat.

As a short term test (I did not leave it in place) I lifted the ground on the utility post with a three to two prong adapter that happened to be available on the utility post. In that configuration (no ground), the GFCI did not trip when I powered up my panel.

I continued to do my work by using an extension cord and not powering my AC panel on the boat.

Last Spring I worked on the boat from a non-GFCI utility pole without any problems. I had no shore power problems over the Summer either.

I have read that the polarity check circuit can cause this situation, and the only way to resolve it and keep a ground in place is to disconnect the reverse polarity light. Does anyone have any experience with this?

Also, in normal operation the GFCI outlet on the boat does not trip and it tests fine (test button).

Thanks,
Steve Pretti

1987 Ericson 32-3 Glory Days
 
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S

supersailor

Contributing Partner
GFCI strip

Be careful with these. We just had a wood yacht burn at the Port Townsend yard when the power strip caught fire outside and under the boat.

Bob Morrison
Terra Nova
 
toddster

toddster

Curator of Broken Parts
Blogs Author
As best I recall, I had the opposite problem with a set-up like that, but it may have included some GF trips. The reverse polarity light would come on. It was due to a bad connection in the adapter. (The combined weight of the cable and adapter was so much that the friction of the plug couldn't hold it in place. I had to add some strategic bailing twine to the situation.) I also got that once at the dock when a crew didn't connect the shore power to the boat socket correctly.
 
Tom Metzger

Tom Metzger

Sustaining Partner
I would open the AC panel and disconnect the reverse power device to see if the problem goes away.

I think it is quite likely the problem because in most yards the power posts are a long way from the source and there are no neutral grounds nearby to keep the neutral voltage close to ground potential. Also, the GFI devices are outdoors where they have lots of moisture around frequently causing leakage which makes the GFI more sensitive than it should be.
 
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