The XBP48RM1U-LI and XBP48RM1U2-LI have battery management electronics in them, and when the battery pack is unplugged from the UPS this is sensed and the battery pack output is turned off. This means we cannot measure the battery voltage from the cable unlike the external battery packs with VRLA Batteries.
To check the battery voltage either
First remove AC power from the UPS
On the Display choose Status
Choose Battery
Scroll to page 5 to see the battery voltage (as the AC power is removed this will just show the battery voltage rather than the charging voltage)
Or
First remove AC Power from the UPS
Measure the voltage on the Battery Pack Anderson socket with a voltmeter (as AC power is removed this will just show the battery voltage rather than the charging voltage)
Released for:APC Denmark