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<div>At 22:38 -0500 26/4/11, William Dorsett wrote:</div>
<blockquote type="cite" cite><br></blockquote>
<blockquote type="cite" cite>OK, I can see how you could input the
amphr capacity of a given set of new batteries, but would someone
explain how a controller which counts amps can adjust as the battery
bank ages? As the capacity of the bank drops over time, and this
varies by different manufacturers, it still seems that a controller
which measures voltage would track the SOC of the bank better than
current counting.</blockquote>
<blockquote type="cite" cite> </blockquote>
<div><br></div>
<div>Keeping track of SOC by counting Ah is a challenge in itself, but
the battery manufacturers' instructions don't require this.
Fullriver and Surrette require the you make a transition between
Absorption and Float charge regimes/stages at a certain point where
the charging current drops to a given level (although the Rolls FAQ is
puzzling in its wording there - suggesting that you can charge at 0.25
x C20 indefinitely!). Most stand alone RE system controllers do
not possess the ability to monitor the battery current, so they cannot
follow these instructions. This is my concern. </div>
<div><br></div>
<blockquote>At 10:54 -0700 26/4/11, Rick Cullen - Blue Sky Energy,
Inc. wrote:
<blockquote type="cite" cite>There has been some discussion in the
past few days regarding AGM batteries and charge control switching to
Float based on net battery charge current matched to battery size and
that our IPN-ProRemote product can provide this.</blockquote>
</blockquote>
<div><br></div>
<div>Rick's Blue Sky product fits the bill but it seems expensive in
the context of very small systems. Phil Smith of Barden
Batteries in the UK has told me that a correctly programmed Tristar
controller will do a good job even though it does not 'know' the
battery current. This is good news.</div>
<div><br></div>
<div>I am still deeply puzzled about sealed batteries as I learn that
you must not make them gas but you have to be sure to charge them well
(like any other lead acid battery) or they will fail prematurely.
That's why I would like to be able to fit controllers that monitor the
battery current and use this to determine the transition to a float
charge. </div>
<div><br></div>
<div>Maybe it would help if somebody told me what sort of charging
would actually damage a sealed battery. Then I would simply
charge them as hard as the wind/sun allows while avoiding doing
that.</div>
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<div>Hugh Piggott<br>
<br>
Scoraig<br>
http://www.scoraigwind.co.uk</div>
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