I use a $100 700 W inverter in my sailboat. I have it wired with a DC
breaker (plus internal fuse) and the AC goes directly to a GFI outlet
wired-thru to one other outlet. I use an AC DPDT switch to select the
inverter or dockside power (which I almost never use.)

Cheap inverters put out 'modified sine waves' (which are square waves) and
do not ground the neutral side. They do not have built in GFIs. So they
don't meet ABYC requirements. Supposedly non-sine inverters may not work
with some GFI's, but mine works fine when I push the TEST button.

So BoatUS, my insurance company does a survey. They found few issues for a
1968 boat, but they did say the inverter should meet ABYC. Is there any
valid argument I can make to the contrary? I have no intention of buying a
big $1500+ inverter when a little $100 one works fine to run power tools and
grind the coffee in the morning. If I didn't have it wired into the AC none
of this would be a problem. But I like it this way.

Thanks,
Dave Erickson
1968 Apache 37 "Second Sojourn"

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