IBM TotalStorage DS4500, User Manual

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Attention: When you handle static-sensitive devices, take precautions to
avoid damage from static electricity. For details about handling static-sensitive
devices, see “Handling static-sensitive devices” on page 43.
3. Unpack the new fan and communications module.
4. Install the new fan and communications module.
a. Push the new fan and communications module all the way into its chassis
slot.
b. Use a flat-blade screwdriver to tighten the two captive screws on the new
module, securing it into place.
5. Check the fan and communications indicator light. See Figure 42 on page 55 for
the location of the fan and communications indicator light.
v If the amber fault indicator light is on, make sure that the fan and
communications module is inserted all the way into the chassis and secured
in place.
v If the fault indicator light remains on, one or both fans inside the fan and
communications module might be malfunctioning. Replace the failed fan and
communications module with a spare, if available. Otherwise, shut down the
DS4500 Storage Server until you can replace the failed fan and
communications module with a new one.
6. Reconnect the interface cables that you disconnected in Step 1 on page 55 to
the new fan and communications module.
Power supply
The DS4500 Storage Server power system consists of two power supplies. The
power supplies slide into either of the two slots on the back of the DS4500 Storage
Server. The power supplies provide power to the internal components by converting
incoming ac voltage to dc voltage. The power supplies are interchangeable and
redundant. Each power supply uses one power cord. You can plug both power
cords into a common power source or plug each cord into a separate circuit for
power redundancy. One power supply can maintain electrical power to the DS4500
Storage Server if the other power supply is turned off or malfunctions.
Servicing notes
Consider the following factors when you service the power supplies:
v Each power supply has a built-in sensor that detects the following conditions:
– Overvoltage
– Overcurrent
– Overtemperature
If any of these conditions occur, one or both power supplies enter shutdown
mode. All power remains off until one of the following events occurs:
– You cycle the power switches (turn off the power switches, wait at least 30
seconds, then turn on the power switches). For more information, see
“Overtemperature condition and power supply shutdown” on page 37.
– The power supplies automatically resume operation when the ambient air
temperature cools to below 70° C (158° F). When the power supplies
automatically resume operation, the DS4500 Storage Server also resumes
operation.
v You can hot swap (replace) a power supply because the two power supplies
provide redundancy.
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IBM TotalStorage DS4500 Fibre Channel Storage Server: User’s Guide