On 5/19/2016 12:48 PM, Brian wrote:
Thanks Richard, I have looked at these before but a 10amp controller seems
a bit large for my 600ma panel. A 1amp controller would seem more
appropriate.
This one may work just fine, but I can't find any data on power loss or
efficiency of the controller. If it draws 200ma, that is a 30% loss for my small solar panel.

Your 200 MA guess might be very high! The 12-amp controller for my
little home solar system (Xantrex C-12) draws only 7 MA when charging
and 3 MA at night. That is data that should be included in any solar
controller specification sheet.

Actually, if your controller drew 200 MA 24/7, then your solar system
could be a net loss with that panel, because on a daily basis you are
lucky to get more than a few hours of equivalent full-sun power from any
solar panel. Also note that a solar panel only delivers its rated
output under a very specific set of conditions. If all of those
conditions don't simultaneously exist (which is almost always) then you
get less. Probably much less!


Still, charging lead acid batteries without a controller (as you state
later in the thread) is a chancy proposition. I've seen lots of
perfectly good lead acid batteries ruined by overcharging.