IBM 1269-3S2, Installation, Service And User Manual

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IBM System Storage DCS9900 1269-3S2 Storage Expansion Unit Installation, Service, and User Guide
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4.7 Continuous Operation During
Replacement
If a disk unit fails, it can normally be replaced without interrupting the use of the system.
In addition, each enclosure contains two Power Supply/Cooling modules, either of which can maintain
power and cooling to the subsystem while the other is replaced.
4.8 Replacing a Module
Warning When replacing a module, NEVER leave an EMPTY bay in the rear of the enclosure. Obtain a
replacement before removing the problem part.
Please refer to Chapter 2 , ”Getting Started” for information on the initial installation of the plug-in modules
in the IBM System Storage DCS9900 3S2 Storage Expansion Unit.
Warning Observe all conventional ESD precautions when handling IBM System Storage DCS9900 3S2
Storage Expansion Unit modules and components. Avoid contact with backplane components
and module connectors, etc.
4.8.1 PSU/Cooling Modules
Warning Do not remove covers from the PSU/Cooling module. Danger of electric shock inside. Return the
PSU to your supplier for repair.
4.8.1.1 Removing an AC PSU/Cooling Module
Warning Do not remove the faulty PSU/Cooling module unless you have a replacement unit of the correct
type ready for insertion.
If a power supply unit or its fan is faulty, you must replace the whole PSU/Cooling module.
As there should always be two power supply units installed, you can continue working while replacing the
faulty module.
1 Make sure you identify the faulty PSU/Cooling module correctly from the two modules installed.
2 Switch off and disconnect the power supply cord.
3 Squeeze the two latches on the PSU handle together ( Figure 4–3 ) and open the handle to cam the PSU
out of the enclosure ( Figure 4–4 ).
4 Grip the handle and withdraw the PSU ( Figure 4–3 ).
4.8.1.2 Installing an AC PSU/Cooling Module
1 Check for damage, especially to the rear connector on the PSU.