HP StorageWorks XP12000 Disk Array owner's guide (AE002-96029, October 2006)

Backup batteries
In each frame (DKC and DKU), internal nickel-metal-hydride batteries provide backup
powerforthecachememory,sharedmemory,ACPs,CHIPs,anddiskdrives.IfACinput
power is lost
, the backup batteries enable the disk array to continue normal op erations
for up to one minute. If power is not restored within one minute, the disk array executes
either the De-Stage or Backup battery operation mode.
1
If power is restored during the de-staging process, the disk array continues with
the da
ta de-staging an d power off processes.
2
If power is restored during the battery backup period, the disk array either
automatically restarts or must be restarted manually, depending on the setting of
the AUTO PS-ON ENABLE/DISABLE switch on the control panel.
HP representatives will help you determine the best battery mode f or your conguration,
and will congure the selected mode during installation.
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Hardware