Date:         Thu, 9 Feb 1995 13:45:44 -0800
Sender:       Vanagon Mailing List <vanagon@vanagon.com>
From:         rathkem@admin.ci.seattle.wa.us
Subject:      Batteries (I was delusional)

I'm going to try and pull myself out of this one....
I plead lack of caffiene. :0

<---- Begin Included Message ---->
>Date: Thu, 9 Feb 95 12:14:32 CST
>From: David Schwarze <schwarze@superc.nosc.mil>
>To: Multiple recipients of list <vanagon@lenti.med.umn.edu>
>Subject: Re: Westy auxiliary battery (why not keep it going)

>This is not ideal because most of the time, the output of one half of the
>alternator will be wasted charging the almost-full starter battery.  Also,
>what is the fascination with three golf cart batteries?  :)  You are the
>second person that has mentioned this.  The golf cart batteries I have seen
>are all 6 volts, and therefore the third one would be essentially useless.

I got the three battery setup from some presentation I went to...  I don't 
clearly remember the setup for three batteries, but your right it doesn't 
sound right.
We do have one truck with 4 golf cart batteries wired in series-parallel, it 
will run a refrigerator for 17 days. :)

>Deep cycle batteries are not designed to be drained completely.  I think
>the manual for mine said to avoid discharging more than about 75 percent,
>and preferrably 50 percent.  Anything more will greatly accelerate the
>death of the battery.  The golf cart batteries are designed for heavy
>current draw over an extended period, similar to a marine/rv battery.
>Golf cart batteries _are_ deep cycle batteries, just like the marine/rv
>batteries, except that they have even thicker plates (so I'm told) which
>accounts for their extreme mass and longevity when compared to other types
>of batteries.

Again you are right, about the batteries.  The golf cart battery is a very 
deep cycle battery.  I understand that periodic draining of a deep cycle 
battery is a good thing because it maintains the "memory" of the battery.  As 
I understand it, during the charge/discharge cycle of the battery an oxide 
develops on the plates, and without a complete discharge ocassionally the 
battery will not store as much of a charge as long.


>> ** As an aside: in putting together my latest fire truck project I used a 
120 
>> amp dual output alternator one side connected to the truck battery, and the 
>> other side connected to (2) 8d auxillary batteries.  The truck batteries 
are 
>> continually topped off with a shore power connection.  I used the deep 
cycle 
>> because those emergency lights suck the power like nothing else.

>Is that 120 amps per side, or 60/60?  In any case, it sounds expensive.  :)

Again I plead chemical imbalance, the alternator is a 200 amp, with two 
windings providing 100/100 per side.  $ 800.00

Thanks for the corrections.  I'm glad you staightend me out.

Matt Rathke, A little confused.
rathkem@admin.ci.seattle.wa.us
-David

=============================================================================
David Schwarze                  '73 VW Safare Custom Camper (Da Boat)
SAIC Comsystems                 '73 Capri GT 2800 (Da Beast)
San Diego, California           '87 Mustang Lx 5.0 (Da Bruiser?  Soon...)
schwarze@nosc.mil                http://papaya.nosc.mil/~schwarze
=============================================================================


<---- End Included Message ---->