Hello,
(Mine is a problem similar to what other have already posted. TL;DR questions at the end)
I have bought a 5PX 2200 rack mounted UPS in 2011 and it has been going without problem (and an additional EBM since 2013) for all this time in ABM cycling mode.
Now it was apparently time for the batteries to be replaced (which I did for both the UPS and the EBM). Everything works fine, I am getting like-new-runtime on the UPS (tested twice with breakers in front-of the UPS open).
The problem: I have been using it with NUT over USB all the time and NUT even after the replacement still reports ALARM OL RB and "Replace battery!". From what I have gleaned, the UPS needs to be reset in a certain way. I have tried by issuing ups.test.start.quick and ups.test.start.deep command via NUT, but while it executed the test, it did not reset the alarm.
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