Galvanic Isolator

[Ken Juul]

Luna Loca stays in the water year round.  As I spend 3 nights a week on her, I keep the shore power plugged in to keep the refer cold and in the winter heat on the prevent freezing.  It was mentioned that I should have a Galvanic Isolater on the shore power ground line.  Is this a "nice to have" or "got to have item"?   The previous owners kept it in the water year round also (southern boat).  If they installed one, where is the most likely location.  I haven't dropped the electrical panel yet, but things look a little tight to fit a brick sized box back there.  I haven't really looked yet, does the wall at the foot of the bed come out for access?  Any tricks?  thanks for the help and info.

[hdevera]

If the boat is kept in salt water, IMHO this is a should have item.  I had a Valiant 42 a few years ago and it had an electrolysis problem which was starting to erode the brass thru-hulls (which were all bonded together).  Boats kept in fresh water do not have to worry about these small currents that flow when boats are plugged into the dock power lines.  Regarding the location, the isolators are located right next to the 110v power inlet to the boat.  I was planning on buying one (which generally costs about $200, but before I bought it I wanted to see how I could mount it.  What a pleasant surprise to see one already there!!  My boat is hull number 1554.

[Gary Wilson]

We keep Childsong in the water year-round at a marina with shore power plugged in for battery charging and winter heat.
    I installed a galvanic isolator soon after we bought her (used) on the advice of Nigel Calder's book "Boat Owner's Mechanical and Electrical Manual".  He says that an isolation transformer is a better choice, but they are more expensive.
     I installed ours near the shorepower socket.  It required crawling into the cockpit hatch and attaching a mounting board to the underside of the coaming with epoxy paste.  It is out of the way and out of harm there.