To resolve these problems, you need specialized knowledge and equipment that could consume substantial
time and money. However, you can ensure that you have a properly grounded and shielded electrical
environment, paying special attention to the need for electrical surge suppression.
For information about the electrode magnetic compliance standards supported on the Cisco ASR 920 Series
Router, see the Regulatory Compliance and Safety Information for the Cisco ASR 920 Series Aggregation
Services Router document.
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 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 920 Series Router operating
environment.
Rack-Mounting Guidelines
The sections provide guidelines for rack-mounting.
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
rack.
•
When mounting the router in a partially filled rack, load the rack from the bottom to the top, with the
heaviest component at the bottom of the rack.
•
If the rack is provided with stabilizing devices, install the stabilizers before mounting or servicing the
unit in the rack.
Cisco ASR-920-12SZ-IM Aggregation Services Router Hardware Installation Guide
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Preparing for Installation
Radio Frequency Interference
