Date:         Tue, 11 Jan 2011 11:45:35 -0800
Reply-To:     Don Hanson <dhanson928@GMAIL.COM>
Sender:       Vanagon Mailing List <vanagon@gerry.vanagon.com>
From:         Don Hanson <dhanson928@GMAIL.COM>
Subject:      Solar power question..semi-vanagon related...
Content-Type: text/plain; charset=ISO-8859-1

   I forgot my solar panel for the vanagon when I left Wa. State this
Xmas.   (Solar Power, at that time of year, in the NW US area, it's not
exactly at the forefront of one's awareness)   So I am depending on my 84's
alternator to keep the vanagon batteries up...so far without any issues with
about 15 miles of driving the van every few days.

  So that is good, but our  '80s-era camping trailer is not doing so well on
Solar power alone.   I don't have all the particulars right in front of me
but I want to try to figure out just what I need to do to make this all
work.   Right now, it is very marginal, the electrical performance of the
trailer.

   We have a pretty big solar panel that used to keep us going, but always
"just ok", unless there was no sun for two full days. If no sun, we have a
crappy noisy Coleman generator that seems to work...   We have two Napa
'combo' RV/marine batts.  Both are fairly new (1 is 2yrs, 1 is one year
old).

 My S.O. insists on having on her stereo radio whenever she is in the
trailer.  Older unit with 4 speakers.  Could  that the main culpurt?   Can
something like that, running perhaps 6hrs a day draw down the 12v supply to
almost dead?  How do I measure the draw from that?  I have a simple R.S.
digital multimeter with DCV, OHM, DCA, and ACV scales.   I assume I would
use the DCA range and perhaps the 200ma or maybe the 20ma scale to read
across the breaker/fuse panel, with that stereo on, until I see some juice
going out...and from the reading, I can reverse-engineer how much energy I
have to put back each day  to keep her happy and listening to NPR, non-stop.

   I just was trouble shooting yesterday and found my 30"X30" solar panel
was not getting everything through to the batteries..I cleaned up the
connections and also found one battery was pretty low on
electrolyte...topped that up.  I have just a crappy LED battery charge
indicator and with a full day of sun, I get the batteries up to
'poor'....With my generator running for an hour, I can make the meter read
'good' with 'full charge' being the next one up.  Just about 5hrs of the
radio and a couple of interior lights on seems to suck out all that juice.

   So I'm sure without meaningful numbers nobody can give me meaningful
specific answers but generally, should just a couple of 12v lights, that
"70s-era" stereo radio, and a little juice to pull up drinking water from
the tanks be using up all the battery?   Am I looking at something wrong, or
are we simply under-powered and need more battery and/or more solar?

   anybody want to chime in?

  Don Hanson