IBM DS3500, Installation, User'S, And Maintenance Manual

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AC power supply and fan units
The DS3500 storage subsystem (models DS3512-C2A and DS3524-C4A) and EXP3500 storage enclosure
(models EXP3512-E2A and EXP3524-E4A) each have two removable ac power supplies. Each ac power
supply contains two fans. The four fans pull air through the drives from front to back across the drives.
The fans provide redundant cooling, which means that if one fan fails, the remaining fans continue to
provide sufficient cooling to operate the storage subsystem or storage enclosure. If one power supply is
turned off or malfunctions, the other power supply maintains electrical power to the storage subsystem
or storage enclosure. To preserve the optimal airflow, do not remove a failed power supply from the
chassis until you are ready to replace it with a new power supply.
Figure 1-9 shows the ac power supply components.
DC power supply and fan units
The DS3524 storage subsystem (model C4T) and EXP3524 storage enclosure (model E4T) each have two
removable dc power supplies. Each dc power supply contains two fans. The four fans pull air through
the drives from front to back across the drives.
The fans provide redundant cooling, which means that if one fan fails, the remaining fans continue to
provide sufficient cooling to operate the storage subsystem or storage enclosure. If one power supply is
turned off or malfunctions, the other power supply maintains electrical power to the storage subsystem
or storage enclosure. To preserve the optimal airflow, do not remove a failed power supply from the
chassis until you are ready to replace it with a new power supply.
Figure 1-10 on page 1-13 shows the dc power supply components.
Hot-swap power supplies
Filler panel
ESM
1 2
ESM
Figure 1-8. Rear view, single ESM model storage enclosure
Power
switch Power
connector Power
switch Power
connector
Figure 1-9. AC power supply components
1-12
System Storage DS3500 and EXP3500: Installation, User's, and Maintenance Guide