Working With Hot-Swap Power Supplies - IBM TotalStorage 300 Service Manual

3. Install the new fan unit.
4. Check the LEDs.

Working with hot-swap power supplies

The RAID storage controller power system consists of two power supply CRUs. The
power supply CRUs provide power to the internal components by converting
incoming ac voltage to dc voltage. One power supply CRU can maintain electrical
power to the unit if the other power supply is turned off or malfunctions. The power
supply CRUs are interchangeable (by reversing the locking levers).
Each power supply CRU has a built-in sensor that detects the following conditions:
v Over-voltage
v Over-current
v Overheated power supply
If any of these conditions occurs, one or both power supplies will shut down. All
power remains off until you cycle the power switches (turn the power switches off,
wait at least 30 seconds, then turn the power switches ON). For more information,
see the User's Reference.
The power supplies are CRUs and do not require preventive maintenance.
v Always keep the power supplies in their proper places to maintain proper
v Use only the supported power supplies for your specific storage server.
a. Place the fan CRU in front of the fan slot.
b. Hold the latch open, and slide the fan all the way into the slot. If the fan
does not go into the bay, rotate it 180°. Ensure that the latch is on the side
closest to the center of the storage server.
c. Release the latch. If the lever remains open, pull back on the fan slightly,
and then push it in again until the latch snaps into place.
The Fault LEDs turn off after a few seconds; if they remain on, refer to the
User's Reference .
controller-unit cooling.
Chapter 5. Installing and replacing IBM NAS 300 components
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