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Cisco ASR-920-24SZ-IM, ASR-920-24SZ-M, ASR-920-24TZ-M Aggregation Services Router Hardware Installation Guide
Chapter 2 Preparing for Installation
Site Planning
Caution The Cisco ASR 920-24SZ-IM, ASR-920-24SZ-M, ASR-920-24TZ-M Router is not recommended to be
installed in an enclosed rack because the chassis requires an unobstructed flow of cooling air to maintain
acceptable operating temperatures for its internal components. If you use an enclosed rack, ensure that
the air flow requirements are maintained as discussed in Air Flow Guidelines, page 2-10.
Equipment Rack Guidelines
The placement of a rack can affect personnel safety, system maintenance, and the system’s ability to
operate within the environmental characteristics. Choose a proper location for the Cisco ASR
920-24SZ-IM, ASR-920-24SZ-M, ASR-920-24TZ-M Router by following the guidelines described
here.
Locating for Safety
If the Cisco ASR 920-24SZ-IM, ASR-920-24SZ-M, ASR-920-24TZ-M Router is the heaviest or the only
piece of equipment in the rack, consider installing it at or near the bottom to ensure that the rack’s center
of gravity is as low as possible.
For additional information about the proper placement of electronic equipment, consult the
GR-63-CORE, Network Equipment Building System (NEBS) Requirements: Physical Protection
document.
Locating for Easy Maintenance
It is recommended that you maintain a minimum clearance distance as mentioned below, at all times.
• front clearance—12.7 cm
• rear clearance—10 cm
This space ensures that you can remove the Cisco ASR 920-24SZ-IM, ASR-920-24SZ-M,
ASR-920-24TZ-M Router components and perform routine maintenance and upgrades easily.
Avoid installing the Cisco ASR 920-24SZ-IM, ASR-920-24SZ-M, ASR-920-24TZ-M Router in a
congested rack and consider how routing of cables from other pieces of equipment in the same rack could
affect access to the router cards.
The front and rear of the chassis must remain unobstructed to ensure adequate airflow and prevent
overheating inside the chassis.
To avoid problems during installation and ongoing operations, follow these general precautions when
you plan equipment locations and connections:
• Use the show environment all command regularly to check the internal system status. The
environmental monitor continually checks the interior chassis environment; it provides warnings
about high temperature and creates reports on other potentially dangerous occurrences. If warning
messages are displayed, take immediate action to identify the cause, and correct the problem.
• Keep the Cisco ASR 920-24SZ-IM, ASR-920-24SZ-M, ASR-920-24TZ-M Router off the floor and
out of areas that collect dust.
• Follow ESD-prevention procedures to avoid damage to equipment. Damage from static discharge
can cause immediate or intermittent equipment failure.