Safety With Electricity - Cisco ASR 903 Hardware Installation Manual

Preparing for Installation
Invisible laser radiation present. Statement 1016
Warning
Warning Hazardous network voltages are present in WAN ports regardless of whether power to the unit is OFF or
ON. To avoid electric shock, use caution when working near WAN ports. When detaching cables, detach
the end away from the unit first. Statement 1026
Blank faceplates and cover panels serve three important functions: they prevent exposure to hazardous
Warning
voltages and currents inside the chassis; they contain electromagnetic interference (EMI) that might disrupt
other equipment; and they direct the flow of cooling air through the chassis. Do not operate the system
unless all cards, faceplates, front covers, and rear covers are in place. Statement 1029
Hazardous voltage or energy is present on the backplane when the system is operating. Use caution when
Warning
servicing. Statement 1034
Invisible laser radiation may be emitted from disconnected fibers or connectors. Do not stare into beams
Warning
or view directly with optical instruments. Statement 1051

Safety with Electricity

Before working on a chassis or working near power supplies, unplug the power cord on AC units; disconnect
Warning
the power at the circuit breaker on DC units. Statement 12
Before working on equipment that is connected to power lines, remove jewelry (including rings, necklaces,
Warning
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. Statement 43
To prevent accidental discharge in the event of a power line cross, route on-premise wiring away from
Warning
power cables and off-premise wiring, or use a grounded shield to separate the on-premise wiring from the
power cables and off-premise wiring. A power line cross is an event, such as a lightning strike, that causes
a power surge. Off-premise wiring is designed to withstand power line crosses. On-premise wiring is
protected from power line crosses by a device that provides overcurrent and overvoltage protection.
Nevertheless, if the on-premise wiring is in close proximity to or not shielded from, the off-premise wiring
or power cable during a lightning strike or power surge, the on-premise wiring can carry a dangerous
discharge to the attached interface, equipment, or nearby personnel. Statement 338
Cisco ASR 903 Aggregation Services Router Hardware Installation Guide
Safety with Electricity
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