Date: Wed, 3 Sep 1997 06:39:09 -0700
Reply-To: Bob Bellanca <bajatrvlr@ABAC.COM>
Sender: Vanagon mailing list <Vanagon@Gerry.SDSC.EDU>
From: Bob Bellanca <bajatrvlr@ABAC.COM>
Subject: Re: aux battery ideas
Content-Type: text/plain; charset=ISO-8859-1
Rick,
Having lived in Baja for years on solar power, I thought I'd take a swipe
at your question...First of all, let's address what it is you're going to
with all this new found energy. If it's just going to be for a reading
light, occasional music, etc; or, a small cement mixer/margarita blender,
the approch is a bit different...Also, the time you're going to be on the
hook, so to speak (ie: time between driving the van and parking). This will
dictate how much solar generating power (in watts) is enough.
To address your concerns about interaction between a dual battery solenoid
and the existing charger, let me ask you this, if your main concern is
maintaining the house battery alone, no problem if it's isolated by a
solenoid (not a diode). Even if it wern't, it still wouldn't be a problem,
you'de just have to approch it a little differently is all. And, by
existing charger I assume you mean the alternator. Yep, electrons are like
water, they'll flow to the lowest level and that's usually the battery. The
electricity from the alt. can't backfeed to the solar panels because
they're protected by diodes. And, the alternator is also. As long as you
put some kind of regulator with the solar panel, you're covered.
Now, on to the next question... The rocket ship meter that tells you
everything...My advice to you or anyone else is to forget it. You don't
need it. A good digital volt meter with a resolution of at least .1 (point
one) volts will tell you more about where you stand with your batteries
than anything else. These meters would be OK if the batteries they were
supposed to monitor were consistant with their ratings throughout their
lifespan. BUT, they're NOT!
I have a diesel Westy with only one battery. A long time ago, I modified
the battery compartment (in the engine compartment) to accept a group 27
(120 amp hr) deep cycle battery. Expierience has shown me that I didn't
have to start up the van for about 5-7 days using the normal camping type
stuff. My suggestion to you is to not bother with solar power unless you
plan on living in the van and not moving for long periods of time. Have fun
and let me know if you have any more questions,
Bob Bellanca
> From: Rick Gordon <rickgo@HALCYON.COM>
> To: Vanagon@GERRY.SDSC.EDU
> Subject: aux battery ideas
> Date: Wednesday, September 03, 1997 12:20 AM
>
> i've been doing a little reading of "Home Power" magazine lately and I'm
> wondering about the design of a solar system to recharge the batteries.
> any one with experience in this area? My main concern is the interaction
> with the dual-battery solenoid and the existing charger - it would be
nice
> to have the whole system wired together to get electrons from solar
and/or
> alternator.
>
>
> another thing i was noting was the use of some sophisticated metering
> equipment to monitor actual amp-hours available in a battery and its true
> voltage.
> one brand is called "E-meter" from a seattle company named "Cruising
> Equipment" which I presume reflects its maritime origins. Anyone
familiar
> with the use of these? It may be overkill at approx US$200 but it may
give
> you that accuracy that the LEDs lack!
>
> -rick
>
> Rick Gordon
> Bainbridge Island, WA, USA
> -------------------------------------
> rickgo@halcyon.com
> http://www.halcyon.com/rickgo/
> KC7QEG
> finger for PGP public key fingerprint
> -------------------------------------
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