At 14:19 -0700 21/4/11, Starlight Solar, Larry Crutcher wrote:
I disagree about AGM life. I have heard others say this about AGM's
but it has not been our experience. I personally have a 900AH bank
that is 6 years old and shows little signs of aging. I have
equalized the batteries twice to keep the capacity up(each one
individually, constant current, unregulated voltage) We only sell
and install battery based systems at our retail store and about 50%
of sales are AGM batteries. We have found that they
have similar life to flooded batteries but with great benefits.
I am curious about AGM battery charging set-points. I may be using
Rolls AGM batteries for a telemetry application (unattended) with
wind and PV inputs. This will be 'opportunity charging'. I wonder
what set points I should use for absorption and float? Is it safe to
set absorption to 29 volts (temperature compensated)? I may not be
able to set it this high since the voltage will exceed 30 in cold
weather and this may interfere with equipment. But will the
batteries like that voltage? Float would be lower of course. But in
my experience the Tristar flits between the two settings in a
slightly random fashion.
I am also puzzled by the above statement where Larry charges each
battery string at constant current, unregulated voltage. I wonder
what current is suitable?
thanks
--
Hugh Piggott
Scoraig
http://www.scoraigwind.co.uk
_______________________________________________
List sponsored by Home Power magazine
List Address: RE-wrenches@lists.re-wrenches.org
Options & settings:
http://lists.re-wrenches.org/options.cgi/re-wrenches-re-wrenches.org
List-Archive: http://lists.re-wrenches.org/pipermail/re-wrenches-re-wrenches.org
List rules & etiquette:
www.re-wrenches.org/etiquette.htm
Check out participant bios:
www.members.re-wrenches.org
