• If an electrical accident occurs, proceed as follows:
• Use caution, and 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 whether the person needs rescue breathing or external cardiac compressions; then take
appropriate action.
In addition, use the following guidelines when working with any equipment that is disconnected from a power
source, but still connected to telephone wiring or network cabling:
• Never install telephone wiring during a lightning storm.
• Never install telephone jacks in wet locations unless the jack is specifically designed for it.
• Never touch uninsulated telephone wires or terminals unless the telephone line is disconnected at the
network interface.
• When installing or modifying telephone lines, use caution.
Power Supply Considerations
Check the power at your site to ensure that you are receiving clean power (free of spikes and noise). Install a
power conditioner if necessary.
This equipment is designed for connection to TN and IT power systems. Statement 16
Warning
Preventing ESD Damage
This equipment needs to be grounded. Use a green and yellow 6 AWG ground wire to connect the host to
earth ground during normal use. Statement 383
Warning
Electrostatic discharge (ESD) can damage equipment and impair electrical circuitry. ESD can occur when
electronic printed circuit cards are improperly handled and can cause complete or intermittent failures. When
removing and replacing modules, always follow ESD prevention procedures:
• Ensure that the router chassis is electrically connected to earth ground.
• Wear an ESD-preventive wrist strap, ensuring that it makes good skin contact. To channel unwanted
ESD voltages safely to ground, connect the clip to an unpainted surface of the chassis frame. To guard
against ESD damage and shocks, the wrist strap and cord must operate effectively.
• If no wrist strap is available, ground yourself by touching a metal part of the chassis.
• When installing a component, use any available ejector levers or captive installation screws to properly
seat the bus connectors in the backplane or midplane. These devices prevent accidental removal, provide
proper grounding for the system, and help to ensure that bus connectors are properly seated.
• When removing a component, use available ejector levers or captive installation screws, if any, to release
the bus connectors from the backplane or midplane.
• Handle components by their handles or edges only; do not touch the printed circuit boards or connectors.
Cisco ASR 903 and ASR 903U Aggregation Services Router Hardware Installation Guide
56
Preparing for Installation
Power Supply Considerations