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<DIV><FONT face=Arial><SPAN class=937293103-04102010>I have a customer with a
set of 24 Concord PVX-6480s that have twice failed during grid outages during
the night. No large loads are on the critical load panel and, since it's at
night when they drop to 50% dod, I'm not sure what's up with them. </SPAN><SPAN
class=937293103-04102010>I plan on cleaning and retightning all the cable
connections first to eliminate that possibility then checking VOC of each
cell.</SPAN> </FONT></DIV>
<DIV><FONT face=Arial><SPAN class=937293103-04102010>Eventually we'll install a
25 kW genset but my first task is to find out the state of the batterys. The
system turns five next spring so I don't think they are near an early
death. </SPAN><SPAN class=937293103-04102010>The BOS is 2 Sunny Island 4248s
with upgraded chipsets and the charger is set to spec though that may need to be
bumped up. The only culprit I suspect is the high summer temperatures in
this unconditioned equipment room. </SPAN></FONT></DIV>
<DIV><FONT face=Arial><SPAN class=937293103-04102010>Finally it may be time to
invest in a capacity tester. What brand is popular among those
Wrenches with lots of experience in diagnosing a batterys health? The
Concord DC5000 only comes in 12 & 24 V models and these are 2V cells.
</SPAN></FONT></DIV>
<DIV><FONT face=Arial><SPAN class=937293103-04102010>Thanks as
always</SPAN></FONT></DIV>
<DIV><FONT face=Arial><SPAN class=937293103-04102010></SPAN></FONT> </DIV>
<DIV>
<DIV>Jim Duncan</DIV>
<DIV>North Texas Renewable Energy</DIV>
<DIV>486 W.N. Woody Road</DIV>
<DIV>Azle Texas 76020</DIV>
<DIV>
<DIV>
<DIV>NABCEP Certified Solar PV</DIV>
<DIV>Installer No.31310-57</DIV>
<DIV>TECL 27398</DIV></DIV></DIV>
<DIV><A href="mailto:ntrei@1scom.net">ntrei@1scom.net</A> </DIV>
<DIV>817.917.0527</DIV>
<DIV><A href="http://www.ntrei.com/">www.ntrei.com</A></DIV>
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