Air Flow Guidelines For Etsi Rack Installation - Cisco ASR-920-12CZ-A Hardware Installation Manual

Chapter 2 Preparing for Installation
12.7cm
(127mm)
Airflow
Front
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When mounting the router in any type of rack equipment, ensure that the inlet air to the router does not
Caution
exceed 70° C.

Air Flow Guidelines for ETSI Rack Installation

To install a Cisco ASR 920 Series Router in a 2-post or 4-post rack, the front and rear doors of the
cabinet must be removed. It is recommended that you maintain a minimum clearance distance as
mentioned below, at all times.
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If you are mounting the chassis in a 4-post enclosed cabinet, ensure that you have a minimum of 10 cm
of clearance on each side of the chassis.
OL-32751-01
If airflow through the equipment rack and the routers that occupy it is blocked or restricted, or if the
ambient air being drawn into the rack is too warm, an overtemperature condition may occur within
the rack and the routers that occupy it.
The site should also be as dust-free as possible. Dust tends to clog the router fans, reducing the flow
of cooling air through the equipment rack and the routers that occupy it, thus increasing the risk of
an overtemperature condition.
Enclosed racks must have adequate ventilation. Ensure that the rack is not congested because each
router generates heat. An enclosed rack should have louvered sides and a fan to provide cooling air.
Heat that is generated by the equipment near the bottom of the rack can be drawn upward into the
intake ports of the equipment above.
When mounting a chassis in an open rack, ensure that the rack frame does not block the exhaust fans.
When rack-installed equipment fails, especially equipment in an enclosed rack, try operating the
equipment by itself, if possible. Power off all the other equipment in the rack (and in adjacent racks)
to give the router maximum cooling air and clean power.
Avoid installing the Cisco ASR 920 Series Router in a location in which the chassis air intake vents
may draw in the exhaust air from adjacent equipment. Consider how the air flows through the router;
the airflow direction is front to back, with ambient air drawn in from the vents located on the sides
of the chassis.
front clearance—12.7 cm
rear clearance—10 cm
Cisco ASR 920 Series Aggregation Services Router Hardware Installation Guide
10cm
(100mm)
Airflow
Airflow
Airflow
Site Planning
12.7cm
(127mm)
Airflow
1 RU
Front
2-13