Replace Chassis Components
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
Repeat Step 1 through Step 3 for the other power tray, if installed.
Caution
Reconnect DC Power
Follow these steps to reconnect DC power to a DC power tray:
Procedure
Step 1
Set the power switch to the OFF (0) position.
Step 2
Check that the circuit breaker assigned to the DC power source you are reconnecting is powered OFF (0).
Step 3
Reconnect the DC power cables in the following order.
a) Positive (RTN) cables first.
b) Negative (PWR) cable last.
c) Repeat Step 1 through Step 3 for the other power trays.
Caution
Caution
Step 4
Replace the clear plastic safety covers over the DC power connection terminal studs and tighten the screws.
Step 5
Set the DC power source circuit breaker to ON (1).
Step 6
Set the power tray switch to ON (1).
Caution
Replace HVAC and HVDC Power Module
Follow these steps to remove HVAC and HVDC power modules from the chassis.
It is not necessary to disconnect all power from the router to replace components, including power
modules.
To prevent injury and damage to the equipment, always attach the ground and source DC power
cable lugs to the power tray terminals in the following order: (1) positive (+) to positive (+),
(2) negative (–) to negative (–).
Do not overtighten the nuts that secure the DC power cables to the power tray terminals. The
nuts should be tightened using the 7/16 hex socket and torque wrench to a torque of 45–50 in-lb.
Use this procedure only when reconnecting power to all power modules in a system that is powered
down completely.
Hardware Installation Guide for Cisco 8800 Series Routers
Reconnect DC Power
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