View Single Post
Old 08-18-2017, 09:56 PM   #12
Insequent
TF Site Team
 
Insequent's Avatar
 
City: Brisbane
Vessel Name: Insequent
Vessel Model: Ocean Alexander 50 Mk I
Join Date: Mar 2012
Posts: 3,673
I bought my boat in the PNW, at Edmonds. One day the marina called me and said that they had received a complaint from a guy further down the dock about rapidly depleting zinc anodes, so they tested power to all the boats on the dock. Mine was the problem.

So I engaged a local service provider, and he quickly established that it was a serious problem. With a bunch of electrical stuff operating I managed to draw 30A from the shore power pedestal. The active wire showed 30 A but he measured only 15 A on the neutral! There was 15 A returning via the water! Fortunately no incidents, at least while I owned the boat but the PO had kept the boat on Lake Union for a time. Perhaps the problem only arose late in his period of ownership when he added a second generator, and he had only been in saltwater since that time.

The issue was very difficult to solve. There was a jumper from neutral to earth on the Krauss & Naimar 'shorepower-gen1-gen2-off' switch that was only visible using a small mirror on an extendable stalk. I surmise that whoever installed the second genny, and the new Kraus & Naimar switch, basically did not know what they were doing!

I had the Port Townsend Shipwright's CoOp refit my boat, and part of that was adding in 230 VAC 50Hz inverter and circuits. They were the one's who solved the issue I described above as well. As part of the electrical work I purchased the Australia and New Zealand Standard applicable to boats and marinas. It specified ELCI in the shore supply. I also have an isolation transformer. Boat electrics should always be done right, by qualified and experienced professionals.
__________________
Brian
Insequent is offline   Reply With Quote