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4-4
EMC CX200-Series DPE2 Hardware Reference
The Standby Power Supply (SPS)
In rackmount installations, an SPS unit fits in a tray beneath the
CX200 to which it connects. Figure 4-2 shows the SPS in a cabinet
with a CX200.
Figure 4-2
SPS Installation, Front and Back Views
In the event of a power failure, an SPS provides backup power until
the storage processor has flushed its write cache data to the CX200
disks. The storage processor then shuts the SPS power off. If the cache
flush has not completed within 60 seconds — more than enough time
to flush a full cache — or if the storage processor has failed, then the
SPS shuts itself down to prevent deep discharge. If there is no ac inlet
power and the SPS is shut down, all status lights will be off.
When power returns, the SPS starts recharging. It may reach a state of
full charge relatively quickly. If power remains off for a long period
— days or weeks — the battery may require more time to charge
fully. The storage processor will not use the write cache unless it
detects a fully charged SPS.
Battery lifetime depends on the number of discharge cycles and
depth of discharge. In a typical environment, a battery pack can last 3
to 5 years. Battery pack lifetime is shorter in locations that have
frequent ac outages.
EMC2475
Standby Power Supply (SPS)
Rear
Front
Mounting Tray with
Standby Power Supplies
(Behind the Bezel)
Filler Panel
Summary of Contents for CX200-Series
Page 4: ...EMC CX200 Series DPE2 Hardware Reference iv ...
Page 42: ...2 18 EMC CX200 Series DPE2 Hardware Reference Installing a CX200 Series DPE2 ...
Page 64: ...3 22 EMC CX200 Series DPE2 Hardware Reference Servicing and Upgrading a CX200 Series DPE2 ...
Page 80: ...A 12 EMC CX200 Series DPE2 Hardware Reference Technical Specifications and Operating Limits ...
Page 86: ...g 6 EMC CX200 Series DPE2 Hardware Reference Glossary ...