If it were me, I would wire the 2 extra batteries in parallel to the
existing house battery and relay/switch arrangement. I assume you want
more amp hours available. Parallel wiring will do that. It will give
you more amps, but still keep the circuit at 12V.

Also, if I installed a really *large* draw item(s), I would also make
sure the gauge of existing wiring, and fuses, switches, etc., was
appropriate.

I know there has been reference on this list to marine type
books/literature regarding 12V wiring. Sorry I can't recall the names
right now, but I'm sure there's mucho stuff on line about that. Might
be a good idea to have a look for a book like that.

--- :^)

Cheers,

Neil.

On Thu, May 15, 2008 at 10:46 PM, Monsieur <obeechi@runbox.com> wrote:
> How would one set up 4 batteries in the Vanagon? I have a battery switch, with a type of relay between them, so one is the engine battery and one is the house battery. There is also an inverter that is wired only to the house battery. The battery switch allows for starting the engine from either battery.
>
> The idea of adding two more batteries to this confuses me. Would I need three battery switches, one two switch between the two other switches?... but I also want batteries three and four to run the inverter as well...
>

--
Neil Nicholson. 1981 Air Cooled Westfalia - "Jaco"

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