"Adrian Smith" wrote in
. uk:

Power 2000-3000 watts.

Hmm....let's see.....I assume you have a 12V system....right?

A little math lesson.

3000W divided by 12V = 250 amps, plus a little loss let's call it 260 amps
just for fun. Hmm...The house battery has a 330AH rating at 20 amps (not
260 amps). At 260 amps, it probably has a rating around 100AH, if it
doesn't explode trying to provide 260 amps for "a while", boiling the
electrolyte. (They're not very efficient at high currents, actually.)

100 AH divided by 260A = .385 hours to DEAD or about 23 minutes. If we run
them DEAD they'll recharge about 20 times, which isn't good. So, we
discharge them to 50% capacity, not 100%, so that drops us to 11.5 minutes
at 3KW.

Not much time, is it? Bigger batteries? 330AH is the rating for huge L-16
batteries, not deep-cycle 130AH "marine batteries". It'd be ok if we had
6,250AH submarine cells, but I doubt you could float that much weight or
have a place to put them and still be able to sit down.

Nope....math lesson over.....sorry. You're in need of a GENERATOR, not an
inverter at this level of usage....It just makes more sense.

Larry

NOTHING is funnier than a captain with a new 4KW inverter, walking down the
dock with his electric heater in his hands, with that big smile on his
face....(c;