1-16
CiscoASR 9000 Series Aggregation Services Router Hardware Installation Guide
Chapter1 Preparing for Installation
Site Requirement Guidelines
The fan trays maintain acceptable operating temperatures for the internal components by drawing in cool
air through the air filter, and circulating the air through the card cage. Each power supply is also
equipped with fans that draw cooler air into the front of the power supply and force warmer air out of
the back of the chassis. For information about the types of fan trays used in the chassis, see Power
Module Fans, page4-34.
Note See Rack-Mounting and Air Flow Clearance Guidelines, page 1-20 for details on air-flow clearance
requirements for installation in an enclosed 4-post rack.
Figure1-12 Air Flow Path through the Cisco ASR 9010 Router—Side View
Cisco ASR 9922 Air circulated by four fan trays as shown in Figure1-15. Two fan trays are
located between the line cards in the top cage and the RP and Switch Fabric
Cards (FCs) in the middle cage. Another two fan trays are located between the
middle cage and the line cards in the bottom cage.
Cisco ASR 9912 Air is circulated by two fan trays located above the line cards as shown in
Figure 1-16.
Table1-1 Chassis Air Flow Guidelines (continued)
Router Type Chassis Air Flow
242696
Power modules
Power modules
Fan trays
Front air
intake
Rear air
exhaust plenum
Air exhaust
Room air
RSPs and line cards