Fan Controls And Indicators - IBM TotalStorage DS4000 EXP100 Installation, User's, And Maintenance Manual

deliver dc power. Both power supplies must be installed to meet Electromagnetic
Compatibility (EMC) and cooling requirements. Figure 4 shows the power supply
and the locations of the controls, indicators, and connectors.
Figure 4. Power supply controls, indicators, and connectors
v Hot-swap power supply CRUs: The two hot-swap power supplies are located
v Levers: Unlock these levers when you remove or install a power supply CRU.
v Power LEDs: These green Power LEDs light when the expansion enclosure is
v Fault LED: The amber Fault LEDs light if a power supply failure occurs. The
v Power switches: Use these switches to turn the power supplies on and off. You
v AC power connectors: To provide ac power to the expansion enclosure, you

Fan controls and indicators

The EXP100 has two hot-swappable and redundant fan units, as shown in Figure 5
on page 19. The fan units are located at the back of the expansion enclosure. One
fan will continue to operate if the other fan fails. You can remove and replace the
fan unit while the EXP100 is powered on and accessing drives.
Each fan has a temperature sensor built into the air inlet. This sensor maintains fan
speed to provide the necessary air flow. If the speed of one of the fans drops to a
level that is too low or stops, the Fault LED located on the back of the fan unit
lights, and the General system error LED on the front of the EXP100 lights. For the
locations of the LEDs on the front of the expansion enclosure, see Figure 3 on page
17. For the LEDs on the back of the expansion enclosure, see Figure 5 on page 19.
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IBM TotalStorage DS4000 EXP100 Storage Expansion Enclosure: Installation, User's and Maintenance Guide
on the back of the EXP100. You must install both power supply CRUs, even if
one power supply is not working.
turned on and receiving ac power.
Fault LED for one power supply might also light if it is powered off while the
other power supply is powered on.
must turn on both switches to use the redundant power supplies.
must connect the power cables to the ac power connectors that are located on
the back of the EXP100.
Levers
Power LEDs
Fault LEDs
Power switches
1 Gb/s 2 Gb/s
X10 X1 Conflict
Tray Number
AC power
connectors
Power supply CRUs