Cisco 3725 - Manual (Page 3)

3
Installing AC Power Supplies in Cisco 3725 Routers
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Safety Recommendations
Safety with Electricity
Warning Before working on equipment that is connected to power lines, remove jewelry (including rings,
necklaces, and watches). Metal objects will heat up when connected to power and ground and
can cause serious burns or weld the metal object to the terminals. To see translations of the
warnings that appear in this publication, refer to the Regulatory Compliance and Safety
Information document that accompanied this device.
Follow these guidelines when working on equipment powered by electricity:
• Locate the room’s emergency power-off switch. Then, if an electrical accident occurs, you can
quickly shut the power off.
• Before working on the system, turn off the power and unplug the power cord.
• Disconnect all power before doing the following:
– Working on or near power supplies
– Installing or removing a router chassis or network processor module
– Performing most hardware upgrades
• Do not work alone if potentially hazardous conditions exist.
• Look carefully for possible hazards in your work area, such as moist floors, ungrounded power
extension cables, and missing safety grounds.
• Never assume that power is disconnected from a circuit. Always check.
• If an electrical accident occurs, proceed as follows:
– Use caution, and do not become a victim yourself.
– Turn off power to the system.
– If possible, send another person to get medical aid. Otherwise, determine the condition of the
victim and then call for help.
– Determine if the person 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. It occurs when
electronic 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 properly guard against ESD damage and shocks, the wrist
strap and cord must operate effectively. 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 (Mohms).