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Cisco Network Convergence System 4000 Series Hardware Installation Guide
Chapter 4 Installing Power Components
Disconnecting AC or DC Power
Disconnecting DC Power
Caution
It is not necessary to disconnect all power from the chassis to replace components, including power
modules. See
Chapter 6, “Removing and Replacing Chassis Components.”
Follow these steps to disconnect an individual DC power source from a power tray:
Step 1
Power off the circuit breaker assigned to the DC power source you are disconnecting.
Warning
To ensure that power remains off while you are performing this procedure, lock-out/tag-out the circuit
breaker switch in the OFF (0) position until you are ready to turn it on.
Step 2
Remove the clear plastic safety covers that fit over the DC power connection terminal studs.
Warning
To prevent injury and damage to the equipment, always remove the source DC power cables from the
power tray terminals in the following order: (1) negative (–), (2) positive (+).
Step 3
Disconnect the DC power cables from their terminals in the following order and note the color of each
cable:
a.
Negative (PWR) cables first.
b.
Positive (RTN) cables last.
Step 4
through
for the other power module distribution that needs to be removed.
If it becomes necessary to disconnect
all
DC power from the chassis, follow these steps:
Note
This procedure describes how to disconnect DC power from all power modules in a single DC power
tray. The procedure is the same for each DC power tray, if more than one is installed.
Caution
If only one power tray is installed, performing the following procedure turns off all power to the chassis.
Step 1
Set the power tray switch to the OFF (0) position.
Step 2
Power off (0) the circuit breaker assigned to the DC power source you are disconnecting.
Warning
To ensure that power remains off while you are performing this procedure, lock-out/tag-out the circuit
breaker switch in the OFF (0) position until you are ready to turn it on.
Step 3
Remove the clear plastic safety covers that fit over the DC power connection terminal studs.
Warning
To prevent injury and damage to the equipment, always remove the source DC power cables from the
power tray terminals in the following order: (1) negative (–), (2) positive (+).