Cisco 7200 VXR router User Manual page 76

Site Requirement Guidelines
Planning a proper location for the Cisco 7200 VXR router and the layout of your equipment
rack or wiring closet is essential for successful system operation. Equipment placed too
close together or inadequately ventilated can cause system overtemperature conditions. In
addition, chassis panels made inaccessible by poor equipment placement can make system
maintenance difficult. Following are precautions that can help avoid problems during
installation and ongoing operation.
When you plan the location and layout of your equipment rack or wiring closet, you need
to consider how air flows through your router. The Cisco 7200 VXR routers draw cooling
air in through the intake vent on the right side of the chassis (when you view the router from
the front), and move the air across the internal components and out the exhaust vent on the
left side of the chassis.
Temperature sensors on the network processing engine and I/O controller monitor the
internal air temperature and send warning messages when the internal air temperature
approaches a specified threshold. If the internal temperature exceeds the specified
threshold, the system environmental monitor shuts down all internal power to prevent
equipment damage from excessive heat. (See the "Environmental Monitoring and
Reporting Functions" section on page 1-50 for temperature threshold information.)
Figure 2-2 shows the airflow through the router.
2-8 Cisco 7200 VXR Installation and Configuration Guide