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<div>At 14:52 -0700 28/4/11, Starlight Solar, Larry Crutcher
wrote:</div>
<blockquote type="cite" cite><font face="Arial"
size="-1">...."Until now"?.....</font></blockquote>
<blockquote type="cite" cite><font face="Arial" size="-1">For
proper VRLA battery charging, once it is full, you MUST reduce
the voltage. It does not matter that you are opportunity charging.
What if your turbine is making power 24/7? The voltage will still
need to be reduced after a few hours or have a fixed voltage
setting. I don't think you are ungrateful but again I encourage
you to re-read this thread and the manufacturers instructions. It's
all there.</font></blockquote>
<blockquote type="cite" cite> </blockquote>
<div><br></div>
<div>OK thanks for driving that home. My previous message was
maybe a bit provocative, trying to get to the key issues. The
manufacturers instructions are a bit confusing in places "The
charger can maintain the current I1 indefinitely or until the charger
is shut off or unplugged. This stage is ideal to maintain battery
state of charge...."(Rolls FAQ) The Fullriver instructions
offer two methods where the final voltage is either below or above the
absorb level. In both methods there are criteria that are
unusual for small system charge controllers.</div>
<div><br></div>
<div>It's not going to be possible to follow these instructions
accurately with opportunity charging. For example the initial
charge will likely be outwith (below) the specified range of
currents. It is unlikely that there will be a shunt to measure
current, or a system to monitor dV/dt to determine the transition
points between stages in the process. Nothing will be constant
(except for a programmable voltage limit, given adequate wind/sun) and
there is no assurance that the battery will be fully charged or
discharged to any known level.</div>
<div><br></div>
<div> You state that "<font face="Arial" size="-1">Once you
have programmed the 2512iX charge controller from the IPN Pro, the
controller retains the information and can be installed as a
stand-alone unit</font>" However this does not come with a
battery shunt that I can see. And it's primarily a MPPT solar
controller, with some sort of load control that may or may not be
suitable for wind diversion (which can be done with the 'duo' I
know). The Tristar offers simple diversion load control suitable
for both wind and solar inputs, with a float setting that takes over
(by default) after one hour of absorb time. Whist this is not
likely to fit the manufacturers curves exactly it does seem likely to
do a reasonable job of charging the battery whilst preventing the
balloon of gas in your dramatic photo.</div>
<div><br></div>
<div>I will read the document that you reference (about thermal
runaway) carefully. I am sorry if I seem a slow learner.
This list is an invaluable resource for the industry. I like to
ask naive questions and I get a deeper understanding as a result.
Thanks to all.</div>
<x-sigsep><pre>--
</pre></x-sigsep>
<div>Hugh Piggott<br>
<br>
Scoraig<br>
http://www.scoraigwind.co.uk</div>
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