Cisco 4000-M Replacement Manual page 8

Accessing the Power Supply
Removing the Component Tray from a Chassis without a Safety Latch
Warning
power switch, line voltages are present within the power supply even when the power switch is off
and the power cord is connected. For systems without a power switch, line voltages are present
within the power supply when the power cord is connected.
Take the following steps to remove the component tray from a chassis without a safety latch:
Step 1
Step 2
Step 3
Step 4
Warning
the DC circuit. To ensure that all power is OFF, locate the circuit breaker on the panel board that
services the DC circuit, switch the circuit breaker to the OFF position, and tape the switch handle of
the circuit breaker in the OFF position.
Step 5
Warning
with telephone-network voltages.
Step 6
Caution
hands, to prevent it from falling.
8 Replacing the Cisco 4000 Series Power Supply
Do not touch the power supply when the power cord is connected. For systems with a
Turn OFF the system power.
Attach your ESD-preventive wrist strap.
Remove all network cables. Proceed with Step 4 if you have an AC power supply. Proceed
with Step 5 if you have a DC power supply.
If you have an AC-powered router, remove the power cord.
Before performing any of the following procedures, ensure that power is removed from
If you have a DC-powered router, take the following steps to remove the power cables:
Use a screwdriver to loosen the captive installation screws on the terminal block
(a)
cover.
Lift and remove the terminal block cover.
(b)
Use a screwdriver to remove the three power leads from the terminal block in the
(c)
following order: negative, positive, then ground.
Before opening the chassis, disconnect the telephone-network cables to avoid contact
Loosen the nonremovable chassis release screw on the rear panel of the chassis. (See
Figure 4.)
Support the component tray from underneath, either on your work surface or with your