SHORE POWER; ANODES

[Lobo]

Because my yacht club has GFI on our docks I am unable to plug in shore power. I gather that the reverse polarity in the tug system sends just enough charge back to trip my GFI breaker. Visiting US made power boats to our club usually have the same problem.

I have my vessel battery charger on a plug (it was hard wired -- no plug). When I'm at my dock I run an extension cord from my dock GFI plug to my battery charger plug totally ignoring the 110 volt system on the boat. If I'm visiting at a normal dock, I plug my charger back into the boat system and use normal shore power.

I usually run the fridge while docked so that the beer keeps cold.

I've always hung a sacrificial zinc overboard that is connected into the ground system. I originally had a "fish" but cut that off and replaced it with a 3" x 5" heavy zinc that Ron (Sidetrack, 25R) gave me. (Hint from Ron: clean zincs with a stainless steel brush -- $10 at safety supply stores).

Here's the bonus. I usually had to change shaft and thruster zincs every 4 or 5 months (trim tab ones lasted longer). Since I started bypassing the boat 110v system I'm getting almost a year out of my shaft and thruster zincs.

In winter I run a heater in the boat, so I use another HD extension cord, thru a port hole, and to the heater. I don't (because I can't) run it through the boat 110v system.



Dave
"Lobo"

 

[knotflying]

I was under the impression that as long as you were hooked up properly, having the reverse polarity signal was not an issue. I get that when I use my Honda 2000 and never had adverse consequences.

 

[Lobo]

I'm not an electrical genius -- so this whole matter is a mystery to me. The best I can figure is that somehow the reverse polarity switch (or is it a unit?) on the boat sends just enough of a signal so that the shore power GFI reads "fault" and trips. The problem lies in the GFI, not the boat. The GFI is 5 milliamps, I believe. Very sensitive. Does this make sense to those who know an amp from a bagel? I have yet to find another marina with GFI like we have.

Dave
"Lobo"

 

[Gin]

There is a difference between an amp and a bagel? Who knew?

Gini

 

[knotflying]

Never had that issue with a GFI tripping off because of the boat being connected to it. Perhaps you do have some leakage somewhere and that is causing the GFI to trip. I thought you were getting a reverse polarity reading on the boat panel.

 

[Levitation]

You need to have someone who speaks both electrical and tug to look at your boat. A neutral is connected to the wrong terminal somewhere.

 

[Automaticman865]

I had this same problem when my Cutwater was on stands in my back yard. I could not run ac from the Gfi in my garage to the boat. I'd get about an hour before the shore power breaker trips. Once I moved to a non Gfi outlet to the boat it stayed on forever.
Stuart