We''ve had boats that were all 12v and boats that had an
inverter with most everything but the cabin
lights using 120v. Life is MUCH easier with the 120v setup and a good sized
inverter. We have a 2500 watt unit that powers hair dryers, microwaves and inflatable boat
pumps.
The
inverter also knows to shut off if you''re using too much juice, so you''ll be able to start your engine again. We use the Heart Interface and have never had a problem with it. It may not be the answer to your question, but that''s our experience.