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CiscoASR 9000 Series Aggregation Services Router Hardware Installation Guide
Chapter5 Replacing Cisco ASR 9000 Series Router Components
Removing and Replacing Power System Components
Disconnecting DC Power
Caution It is not necessary to disconnect all power from the router to replace components, including power
modules. See Removing and Replacing Power System Components, page5-12.
Follow these steps to disconnect an individual DC power source from a power tray (Figure3-21 for
version 1 DC power, Figure3-22 for version 2 DC power, or Figure 3-23 for version 3 DC power):
Step1 Power off the circuit breaker assigned to the DC power source you are disconnecting.
Caution To ensure that power remains off while you are performing this procedure, lock-out/tag-out the circuit
breaker switch in the STANDBY (0) position until you are ready to turn it on.
Step2 Remove the clear plastic safety covers that fit over the DC power connection terminal studs.
Caution To prevent injury and damage to the equipment, always remove the source DC power cables and ground
from the power tray terminals in the following order: (1)negative (–), (2) positive (+), (3) ground.
Step3 Disconnect the DC power cables from their terminals in the following order and note the color of each
cable (Figure 3-21 for version 1 DC power, Figure3-22 for version 2 DC power, or Figure 3-23 for
version 3 DC power):
a. Negative (PWR) cables first.
b. Positive (RTN) cables next.
c. Ground cable last.
Step4 Repeat Step 1 through Step 3 for the other power tray, if installed.
If it becomes necessary to disconnect all DC power from the router, follow these steps (Figure3-21 for
version 1 DC power, Figure3-22 for version 2 DC power, or Figure 3-23 for version 3 DC power):
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 router.
Step1 Set the power tray switch to the STANDBY (0) position.
Step2 Power OFF (0) the circuit breaker assigned to the DC power source you are disconnecting.
Caution 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.