[RE-wrenches] Battery capacity testers

[North Texas Renewable Energy Inc]

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. I plan on cleaning and retightning all the cable
connections first to eliminate that possibility then checking VOC of each
cell.
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. 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.
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.
Thanks as always

Jim Duncan
North Texas Renewable Energy
486 W.N. Woody Road
Azle Texas 76020
NABCEP Certified Solar PV
Installer No.31310-57
TECL 27398
ntrei at 1scom.net
817.917.0527
www.ntrei.com
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