Date:         Thu, 15 Jun 2000 23:40:56 -0400
Reply-To:     Marc Perdue <marcperdue@adelphia.net>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Marc Perdue <marcperdue@adelphia.net>
Subject:      Re: dual battery? hobigesuss!
Content-Type: text/plain; charset=us-ascii

The fridge?  Why would you want to run the fridge on an aux. battery when you've
got the propane to run it while camping?  That's kind of a rhetorical question,
but regardless of whatever reasons one may have for this, I always figured you'd
want the extra battery for running things like the stereo and interior lights
for reading or whatever.

Regarding the design of circuits and doubling the fuse size, well, in my 17
years of servicing electronic equipment I've never heard of such a thing.
However, like Bill said, I don't design the stuff either, so who knows?  I do
know this: the fuse won't blow unless you exceed its rated amperage.  Given
that, it seems I would NOT be able to run my stereo (10 amps) AND the fridge on
that 15 amp circuit.  On the other hand, I've sat around in cars and had the
lights, the heater fan, the windshield wipers, AND the stereo going at the same
time WITHOUT the engine being on and without blowing fuses.  Sounds to me like
the Hella kit is performing a simple service at a simple price . . . giving you
one 15 Amp circuit where you had none before.  Given that we can, and do, run
multiple circuits at higher amperage off of our cranking batteries, why can't we
expect to get the same out of the auxiliary battery?  If we design one big
circuit of, say, 50 amps, are we increasing the likelihood of an electrical
fire, or are we just asking for trouble in other ways?  Should we design
multiple, smaller circuits like we have already?

Thank you Beckett, David B., and others, for clarifying some things for me.
This has been an interesting discussion.

Ron, I hope you don't feel that we've ragged on your product too much.  It
probably does exactly what it was designed to do and does it well.  It still
seems as though we should be able to do better than 15 amps out of that extra
battery though . . .

Oh, and Josh?  The Hella kit ought to work perfectly for running your stereo . .
. unless you're one of these guys that's filled your van with 48 subwoofers!
:^)

Peace y'all,
Marc Perdue


Bill Davidson wrote:

> > all I want to do is put in like a motorcycle battery to run my radio while
> I
> > camp
> > out, you know?
> > is this kit going to workout?
> > help?
> > Slopey
>
> Depends on how many amps your radio draws.
> The kit has a 15 amp fuse.
> The fridge draws 7 to 8 amps.
> The water pump....? I forgot.
> Do you have other accessories you want to run of this circuit?
> How many amps are those other accessories.
> Add them up and times by two.
> It is my understanding (I'm not an electrical engineer) that good automotive
> circuit design will size the fuse at about twice the expected amperage
> draw... (for instance the existing fridge fuse is 16 amps).
>
> IMHO that the other problem with the Hella kit... the 15 amp fuse does not
> allow for the addition of accessories... one of the main reason many of us
> add the 2nd battery in the first place.
>
> Bill
> >