Jonathan Jones

2005 Triton 173sport

1984 SeaRay 210

How in the hell did this happen?  Bolt/bracket break or something?

"SHARP GIGS AND TIGHT RIGS"

The night that it got so bad from Hurricane Ike was the last time and my other boat would get swamped if 2 were on the front floundering and a larger boat came by. With two men on the front of it the outboard would be in the air.

I just talked to him and he said that a GFCI is a must and he would not dare to go without one.

But,it will not work unless the generator becomes grounded. Through the boat is not a true ground so it will not work the same, but if the generator was to become grounded and you did not have the GFCI it would be bad. He said that a GFCI measures the voltage on the neutral and compares it to the voltage measured on the hot leg and, it has to be within 5 mv or it will trip the GFCI. With the generator not grounded it should not trip the GFCI.

If there was a exposed wire on one of the lights and you touched it the GFCI would not trip unless you or something conductive was also touching the generator. In an aluminum boat the generator would be grounded to the boat if the rubber feet were removed from the generator (DO NOT REMOVE THEM) and you would be shocked if you did not have the GFCI and there was a short in the wiring. On a wet fiberglass boat you could have a short and not know it until you touched the generator or if there was enough water touching the generator to make a conductive path.

Jonathan Jones

2005 Triton 173sport

1984 SeaRay 210

16' Wellcraft (Tammy II)

 Wise men talk because they have something to say. Fools talk because they have to say something.

Like the post above, the rubber feet keep the generator from being grounded. Therefore the GFCI will not work as it would in your yard (for the lack of a ground). An aluminum boat or a soaking wet fiberglass boat would act as a indirect path to ground if there was a short and a conductive path to the housing or the frame of the generator.

With or without a GFCI: If you were standing on the front of the boat and touched a short in the wiring and touched the bay it will be bad news. The GFCI would not trip because the generator has its on magnetic field. If you had a short and a conductive path back to the generator (aluminum boat, conductive gig pole, or a standing amount of water that was touching the generators frame) you would be hurting without a GFCI, with a GFCI it would trip at 5 millivolts.

You are correct on the grounding lug. There are several guys I know that are using the open frame generators that could ground out in the case of a short through a conductive path.

First scenario:  If you are in an aluminum boat..  "bond" your generator to the boat.  (bolt a cable to the boat and to the genset)  If there is a problem it will use your aluminum boat as a ground and discharge everything into the water.  as long as your ground wire is a good connection then there will be no difference in potential between you and the generator.  (you won't get shocked)  Use the GFCI it will keep you from getting shocked ... to bad

second:  if you are in a fiberglass boat and do not have a ground plane the GFCI is useless.  If there is a bare wire and it has not tripped the installed breaker on your genset then this wire will shock you and it will hurt.  A GFCI will be unable to shunt anything to ground since there is none.  Be care full of wires on a fiberglass hull.  There is no common ground and you will almost always be at some potential other than whatever wire you touch. 

Use plenty of heat shrink (the kind with glue in it) and good quality connectors.  Use plenty of silicon greese (doesn't conduct) in your connectors this will keep water away from the contacts.