T&T: GFCI Tripping

[Peter Bennett]

Tuesday, March 3, 2009, 5:12:18 PM, Peter wrote:

PB> Tuesday, March 3, 2009, 4:08:30 PM, Eric wrote:

ET>>  Hello All.
ET>>  While reading about the problems people are having with shore-based GFCI
ET>> units tripping as soon as the power is plugged in, I was wondering if this
ET>> problem might be quickly solved by installing a galvanic idolater in the
ET>> green ground line as it enters the boat? If done before the ground line was
ET>> attached to anything on the boat it still allows safety, but prevents small
ET>> voltage currents from tripping the GFCI.
ET>>  Or am I wrong here??

ET>> Eric Thompson
ET>> S/V Procrastinator
ET>> South San Francisco

PB> As I read it, the original post from Jake2124 at aol.com indicated that the problem was
PB> due to a fault in the inverter installation.

PB> According to ABYC, the AC neutral and green safety ground _must not_
PB> be connected together on-board, however, some inverters are apparently
PB> supplied with this connection made.

To clarify: The above refers to the neutral and ground from the shore
power - they are connected together somewhere in the marina, and must
not be connected together on the boat.

PB> ABYC also requires that any on-board AC source, such as a generator or
PB> inverter, must connect its own neutral to the vessel ground and green
PB> ground wire.

PB> To comply with these rules, when an inverter is simply passing shore
PB> power through, it must not connect ground and neutral, but shore power
PB> is not available, and the inverter is producing power, it must connect
PB> the neutral at its output to ground.

PB> I assume that moving a screw as mentioned in the original post changes
PB> the inverter's wiring from always connecting neutral to ground to
PB> connecting neutral to ground only while inverting.







-- 
Peter Bennett, VE7CEI    Vancouver, B.C., Canada
Ennos 31 "Honeycomb"
GPS and NMEA info: http://vancouver-webpages.com/peter 
Vancouver Power Squadron: http://vancouver.powersquadron.ca