IBM 8265 Nways ATM Switch, Installation Manual

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Replacing a Defective Fan Unit
This section describes how to replace defective fans for the 8265.
The 8265s are shipped with three installed fan units (Part Number 25H1798). For normal operation, at
least two of these dedicated fan units must be running at all times. Power supply fans help to ventilate the
8265, but they are not designed to act as a substitute for dedicated fan units.
Attention: If more than one fan unit malfunctions, power off the 8265 immediately and do not attempt to
power up again until you have installed at least two fully functional fan units. To ensure optimal 8265
operation, always run the 8265 with a full complement of three fan units.
If only one fan unit malfunctions, you do not need to power off the 8265 before removing and replacing the
defective unit.
To replace a defective fan unit:
1. Remove and save the four corner screws that attach the fan unit to the rear of the 8265.
2. Carefully pull the fan unit straight out from the 8265 fan bay and, before completely removing the fan,
grasp the four-position fan connector cable and disconnect it from the 8265 (see Figure 23).
Screw (one at each comer)
Fan Connector
Fan Connector
Cable
Fan Unit
Figure 23. Replacing a Defective Fan Unit
3. Remove the replacement fan unit from its shipping box and carefully slide the fan into the slot formerly
occupied by the faulty unit. Connectors on the installed fan must be firmly seated in the corresponding
8265 connectors.
Note: The fan begins rotating the moment the unit is plugged in.
4. Verify that the replacement fan is flush with the back of the 8265.
5. Replace the four screws that secure the fan unit to the rear of the 8265.
6. Visually inspect all installed fans to verify that each is turning without interruption.
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IBM 8265: Installation Guide