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charging'</title></head><body>
<div>At 14:19 -0700 21/4/11, Starlight Solar, Larry Crutcher
wrote:</div>
<blockquote type="cite" cite><br></blockquote>
<blockquote type="cite" cite><font face="Arial" size="-1">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.</font></blockquote>
<div><br></div>
<div>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.</div>
<div><br></div>
<div>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?</div>
<div><br></div>
<div>thanks</div>
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</pre></x-sigsep>
<div>Hugh Piggott<br>
<br>
Scoraig<br>
http://www.scoraigwind.co.uk</div>
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