Hi all,

  I have an almost westie (no top, but most everything else inside) with a
second aux. battery that I've been using quite happily for a few years. I
have it wired in to the charging system with a big cannister relay.  I also
use  a Seimans M-20 solar panel with a lighter plug to keep the battery
up.  I have used this panel successfully on many of my camping vehicles,
but I have never had any diode(?) or controller.   Seimans says this panel
limits it's charge to what the battery will take...and that seems to be
true...I have never had any problems with it anyhow....I simply plug it in
to the secondary (coach) power system and let the sun shine.

  I have always tried to unplug the panel when the sun sets, because I've
been told the panel will draw down the battery without any sun....I have
also heard I should have a 'diode' in the line to stop the reverse of
electrons from the battery out to the Night, backwards through the solar
panel.   Is this correct, and will any diode do the trick or should I get a
specific size?  The panel output is pretty low, it is 22" x 12" and does
maybe 1.4 amps?

  Anyway, I would like to perhaps mount the panel semi-permanent, at
times,  on my van's roof or rack and not have to 'deploy' it each day and
unplug it at night.

  Can anyone advise me about this?  Thanks in advance

  Don Hanson