Short backup time
Backup time reducing from 6 hrs of backup to a few minutes withing 4 weeks of purchasing new batteries. what is the standard charging Current (Amp) for the PowerWare 9120 1000VA ? mine reads as 0.44 Amp.
Computers & Internet - Powerware - 9120 UPS System
Answers & Comments
The only way you would get 6 hours backup initially from a Powerware 9120-1000 would be with no load connected(actually 378 minutes when I just looked at the one I have on the test bench). As soon as you apply a load, your displayed (and actual) backup time will reduced. Powerware have battery backup time versus load tables on the product info for the 9130 which is similar and a backup calculator on their website.
Suspect battery failure/faulty cell in a batt
Remove batts and check outside unit
charge up to around 2.27V/cell then check discharge on each batt (12V car lamp is good dummy load)
faulty one will be obvious.
MAKE SURE YOU ARE VERY CAREFUL WITH BATTERIES, THEY ARE VERY DANGEROUS, AND ALWAYS LIVE!
Check you manual for safety procedures, BEFORE working on Batteries.
hope this helps
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