Date: Mon, 7 Jun 2004 19:51:37 -0700
Reply-To: mark drillock <drillock@EARTHLINK.NET>
Sender: Vanagon Mailing List <vanagon@gerry.vanagon.com>
From: mark drillock <drillock@EARTHLINK.NET>
Subject: Re: Dual-Battery Question
Content-Type: text/plain; charset=us-ascii
I don't have to predict what will happen long term, I have seen for
myself. I have 2 of my Vanagons wired that way in my driveway right now.
Had them that way for years. So much malarkey about auto electrics but
it is not that complicated. Isolators are fine but not worth the extra
trouble in Vanagons IMO. Relays are better suited, just as VW used for
dual batteries. Switches work too if you can remember to switch them at
the right times. Jumper cables are too easy to knock out of position to
rely on when people are in or around the vehicle. There are lots of
applications where multiple batteries are connected together to create a
larger battery bank. It is not voodoo. Boats do it, trucks do it, large
RVs do it, electric vehicles do it, off grid solar powered homes do
it.... Just 2 similar batteries in parallel is a pretty simple case.
Whatever is done must be done such that starting current never flows
through the connection between the batteries unless the connection wires
are of a large enough gauge.
Mark
Jack wrote:
>
> Willy,
>
> Have to chime in on this. I think Doug is correct; 2 batteries connected in
> parallel through a very low resistance is not a good thing - hard to predict
> what will happen, long term. You can't guarantee identical conditions, much
> less identical batteries. For a temporary connection, ok. But much better
> through an isolator or some other impedance. Do remember that sparks around
> a charging battery are potentially a *very* bad thing (hydrogen as in
> Hindenberg). //Jack
>
> Date sent: Mon, 7 Jun 2004 17:43:56 -0700
> Send reply to: Doug in Calif <vanagon@ASTOUND.NET>
> From: Doug in Calif <vanagon@ASTOUND.NET>
> Subject: Re: Dual-Battery Question
> To: vanagon@GERRY.VANAGON.COM
>
> > Fin,
> > I have found the two batteries will fight on another and deteriorate.
> >
> > Any un equal difference will constantly pull on one and push the other to
> > hold more which eventually made them both go bad prematurely..
> >
> > Doug
> >
> >
> > ----- Original Message -----
> > From: Fin Beven
> > To: vanagon@GERRY.VANAGON.COM
> > Sent: Monday, June 07, 2004 5:14 PM
> > Subject: Re: Dual-Battery Question
> >
> >
> > For years I have linked my two (identical) batteries with a solid run of 4
> > ga. wire, with crimped-on terminals at both ends. This effectively turns
> > the two batteries into one LARGE battery. What's critically important is
> > to use VERY high quality wire and terminals. If you have access to marine
> > grade (West Marine on the Internet) I think that it's worth the price, as
> > they assume that their equipment will be used in a very harsh electronic
> > environment (salt air).
> >
> > This is not a recommendation, but no problems have resulted. However, I do
> > have a good quality volt-meter that can be left on when the batteries are
> > being used but the engine charging system is not (as when camped
> > overnight). I'm just cautious not to let the voltage drop below 11.8 in
> > moderate weather.
> >
> > Fin Beven
> > '90 Carat, Custom Camper Conversion
> > Pasadena, CA
> > ----- Original Message -----
> > From: Joe Federici
> > To: vanagon@GERRY.VANAGON.COM
> > Sent: Monday, June 07, 2004 11:10 AM
> > Subject: Re: Dual-Battery Question
> >
> >
> > I wouldn't consider it safe but to each his own. That said if your
> > going to do it I would use as large around 6 gauge or better and fuse it
> > for sure it won't take much to over charge the battery and really BAD
> > stuff can happen one you reach that point.
> >
> > The isolator or relay setup isn't that had to do maybe you could take
> > it with you and hook it up on vacation?
> >
> > JFF
> >
> >
> > On Jun 7, 2004, at 1:38 PM, Russell, William wrote:
> >
> > Well, after a weekend of work, I've managed to get my Optima Yellow top
> > installed and the stereo switched over to it. However, I have not yet
> > installed a relay or isolator yet. What I would like to do, for this
> > trip (I leave tomorrow), is employ a manual system. It would seem to me
> > that hooking a wire from the + of the starter batter to the + of the
> > Optima while the car is running would work. I would like to use
> > something a little more graceful than a jumper cable as I will be living
> > in the van for the next week. If I were to route a wire between the two
> > batter compartments and use alligator clips to connect it, would this be
> > safe? What gauge of wire should I use? Should it be fused?
> >
> >
> >
> > Any help is much appreciated.
> >
> >
> >
> > \/\/i!!y
> >
> > 1980 Westfalia "Jazzy"
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