Fujitsu Eternus2000 Manual page 55

IMPORTANT
P3AM-2512-03EN ETERNUS2000 disk storage system User Guide
• If a power failure is detected, data in the cache memory is saved for
up to 48 hours when the battery is fully charged and for up to 96
hours when additional battery is also fully charged.
After AC power supply recovery, the battery recharge process starts
as soon as the ETERNUS2000 is turned back on. It takes up to six
hours to fully charge the battery.
• If a power failure lasts for more than 20ms, data in the cache memory
is saved using the battery. If the power failure ends within 20ms, the
operation can be continued.
• When a power failure is detected, a buzzer will sound for 30 sec-
onds. If this occurs, make sure that the power cord has not been
accidentally unplugged.
• If the remaining power of the installed battery is less than 30 percent,
or a battery unit fails, performance may be degraded temporarily.
• The ETERNUS2000 uses a Nickel-Metal Hydride battery. The cache
memory data retention period during power failure shortens depend-
ing on the remaining battery power. The battery is charged automati-
cally during ETERNUS2000 operation, but if left unattended without
operating for an extended period of time, the battery power remain-
ing will decrease gradually by self-discharge. Make sure to operate
the ETERNUS2000 for more than one to two hours every one to two
months in order to charge the battery.
• Turn on or off the ETERNUS2000 by power switch or battery control
device.
If the ETERNUS2000 is turned off in a way other than previously
described, the battery is charged and discharged. This shortens the
replacement cycle and the battery may need to be replaced earlier
than expected.
Copyright 2009 FUJITSU LIMITED
Chapter 2 Hardware
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