EMC CX200-Series, Справочник по аппаратуре

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SPS Technical Specifications
A-9
Technical Specifications and Operating Limits
Battery Tests
Battery Self-Discharge Times
When you store an SPS, the battery charge level naturally decreases
over time. This is characteristic of all rechargeable batteries. The rate
of self-discharge depends on temperature. Lower storage
temperatures are desirable since the self-discharge rate is lower. The
following graph shows how the remaining charge decreases over
time at different temperatures.
Figure A-1
Typical SPS Self-Discharge Levels at Different Storage Temperatures
Internal Within 60 minutes after powerup and approximately every 2 weeks
thereafter, the SPS itself performs a light test on the batteries. This test lasts
less than one second. It does not verify battery capacity but does check
connectivity and functionality. This test is transparent to other components in
the array. If an actual power failure occurs during the test, the test is
terminated and the unit goes into On-Battery mode.
Full At each storage-system startup, the system software initiates a full power
test. During the test, the system disables write cache and allows the SPS to
stay on for a full 90 seconds.
The system initiates a full test when the SPS is online and fully charged. If
the batteries are charging at test time, the system defers the test until the
next programmed time.
Avoid allowing the battery
to discharge below this
level to allow full recharge
within the SPS time limit.
20 degrees C (68 F)
30 degrees C (88 F)
40 degrees C (104 F)
100
90
80
70
60
50
40
30
20
10
0
3 6 9 12 15 18
Remaining Capacity (%)
Storage Time (Months)
EMC2447