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Cisco ASR 903 Router Hardware Installation Guide
OL-25178-05
Chapter2 Preparing for Installation
Safety Guidelines
Warning
Invisible laser radiation may be emitted from disconnected fibers or connectors. Do not stare into
beams or view directly with optical instruments.
Statement 1051
Safety with Electricity
Warning
Before working on a chassis or working near power supplies, unplug the power cord on AC units;
disconnect the power at the circuit breaker on DC units.
Statement 12
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.
Statement 43
Warning
Do not work on the system or connect or disconnect cables during periods of lightning activity.
Statement 1001
Warning
Before performing any of the following procedures, ensure that power is removed from the DCcircuit.
Statement 1003
Warning
Read the installation instructions before connecting the system to the power source.
Statement 1004
Warning
This product relies on the building’s installation for short-circuit (overcurrent) protection. Ensure that
the protective device is rated: For a -48/-60 VDC installation, the wire shall be 12 AWG minimum with
a 20 A branch circuit breaker. For a 24 VDC installation, the wire shall be 8 AWG minimum with a 40
A branch circuit breaker.
Statement 1005
Warning
This product relies on the building’s installation for short-circuit (overcurrent) protection. For an AC
installation, ensure that the branch circuit breaker is rated a maximum 20A.
Warning
There is the danger of explosion if the battery is replaced incorrectly. Replace the battery only with
the same or equivalent type recommended by the manufacturer. Dispose of used batteries according
to the manufacturer’s instructions.
Statement 1015
Warning
This unit is intended for installation in restricted access areas. A restricted access area can be
accessed only through the use of a special tool, lock and key, or other means of security.
Statement 1017