Radio Frequency Interference; Lightning And Ac Power Fault Interference; Rack-Mounting Guidelines; Precautions For Rack-Mounting - Cisco ASR 902U Hardware Installation Manual

Rack-Mounting Guidelines

Radio Frequency Interference

When electromagnetic fields act over a long distance, radio frequency interference (RFI) may be propagated.
Building wiring can often act as an antenna, receiving the RFI signals and creating more EMI on the wiring.
If you use twisted-pair cable in your plant wiring with a good distribution of grounding conductors, the plant
wiring is unlikely to emit radio interference. If you exceed the recommended distances, use a high-quality
twisted-pair cable with one ground conductor for each data signal.

Lightning and AC Power Fault Interference

If signal wires exceed the recommended cabling distances, or if signal wires pass between buildings, you
should consider the effect that a lightning strike in your vicinity might have on the Cisco ASR 902 Router.
The electromagnetic pulse (EMP) generated by lightning or other high-energy phenomena can couple enough
energy into unshielded conductors to damage or destroy electronic equipment. If you have previously
experienced such problems, you should consult with RFI and EMI experts to ensure that you have adequate
electrical surge suppression and shielding of signal cables in your Cisco ASR 902 Router operating environment.
Rack-Mounting Guidelines
The following sections provide guidelines for rack-mounting the Cisco ASR 902 Router:

Precautions for Rack-Mounting

The following rack-mount guidelines are provided to ensure your safety:
• Ensure that the rack is level and stable before extending a component from the rack.
• Ensure that proper airflow is provided to the components in the rack.
• Do not step on or stand on any component or system when servicing other systems or components in a
• When mounting the Cisco ASR 902 Router in a partially filled rack, load the rack from the bottom to
• If the rack is provided with stabilizing devices, install the stabilizers before mounting or servicing the

Rack Selection Guidelines

The Cisco ASR 902 Router can be mounted in most two-post or four-post, 19-inch equipment racks that
comply with the Electronic Industries Association (EIA) standard for equipment racks (EIA-310-D 19-inch).
The rack must have at least two posts with mounting flanges to mount the chassis.
When mounting a chassis in any type of rack equipment, ensure that the inlet air to the chassis does not
Caution
exceed 65°C.
Cisco ASR 902 and ASR 902U Aggregation Services Router Hardware Installation Guide
56
rack.
the top, with the heaviest component at the bottom of the rack.
unit in the rack.
Preparing for Installation