Cisco 3660 - Manual (Page 5)

Replacing the Mainboard in Cisco 3660 Routers 5
Preventing Electrostatic Discharge Damage
If an electrical accident occurs, proceed as follows:
— Use caution; do not become a victim yourself.
— Turn OFF power to the router.
— If possible, send another person to get medical aid. Otherwise, determine the condition of the
victim and then call for help.
— Determine if the victim needs rescue breathing or external cardiac compressions; then take
appropriate action.
Preventing Electrostatic Discharge Damage
Electrostatic discharge (ESD) can damage equipment and impair electrical circuitry. ESD can occur
when printed circuit cards are improperly handled and can result in complete or intermittent failures.
Always follow ESD prevention procedures when removing and replacing cards. Ensure that the
router chassis is electrically connected to earth ground. Wear an ESD-preventive wrist strap,
ensuring that it makes good skin contact. Connect the clip to an unpainted surface of the chassis
frame to safely channel unwanted ESD voltages to ground. To guard against ESD damage and
shocks, the wrist strap and cord must be used properly. If no wrist strap is available, ground yourself
by touching the metal part of the chassis.
Caution For safety, periodically check the resistance value of the antistatic strap, which should be
between 1 and 10 megohms (Mohm).
Tools and Equipment Needed
You need the following tools and equipment to remove and install the mainboard tray in a
Cisco 3660 router:
•
Number 2 Phillips screwdriver
•
ESD-preventive wrist strap
•
Antistatic mat
Removing the Cisco 3660 Mainboard Tray
Warning Do not touch the power supply when the power cord is connected. For systems with a
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.
Warning Before performing any of the following procedures, ensure that power is removed from
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.
Use the following procedure to remove the mainboard tray:
Step 1 Power OFF the router. However, to channel ESD voltages to ground, do not unplug the
power cable.