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Cisco Catalyst 4900M Switch Installation Guide
78-18350-02
Chapter 3 Installing the Switch
Removing and Replacing the Power Supply
Warning
Blank faceplates and cover panels serve three important functions: they prevent exposure to
hazardous voltages and currents inside the chassis; they contain electromagnetic interference (EMI)
that might disrupt other equipment; and they direct the flow of cooling air through the chassis. Do not
operate the system unless all cards, faceplates, front covers, and rear covers are in place.
Statement 1029
Step 6If the power supply bay is to remain empty, install a blank power supply filler plate over the opening.
Secure the filler plate with the two mounting screws and tighten them with a screwdriver.
Installing a Power Supply
Warning
The plug-socket combination must be accessible at all times, because it serves as the main
disconnecting device.
Statement 1019
Follow these steps to install a power supply:
Step 1Make sure that the power supply you are installing is not connected to a power source and that a power
cord is not connected to the power supply.
Step 2Loosen the two Phillips-head screws from the power supply filler plate (if a filler plate is present).
Step 3Remove the power supply filler plate (if one is present) and set it aside.
CautionUse both hands to grasp a power supply.
Step 4Grasp a power supply handle with one hand. Place your other hand underneath to support the bottom of
the power supply.
Step 5Slide the power supply almost all the way into the power supply bay. Press with both thumbs evenly to
correctly seat the power supply into the connections inside.
Step 6Using a screwdriver, tighten the two captive installation screws on the front panel of the power supply.
Step 7Make sure the power supply power switch is in the off position (O).
Step 8Before you connect the power supply to a power source, ensure that all site power and grounding
requirements have been met.
Step 9Plug the power cord or cords into the power supply.
Step 10Connect the other end of the power cord to a power input source.
CautionIn a system with multiple power supplies, connect each power supply to a separate power source. In the
event of a power source failure, if the second source is still available, it can maintain maximum
overcurrent protection for each power connection.