Cisco CATALYST 6509E 9 SLOT 15U CHASSIS NO POWER SUPPLY NO FAN TRAY Specification Guide

The system fan assembly provides cooling air for the supervisor engine and the switching modules. 

 lists the Catalyst 6500 series switch chassis along with the supported and unsupported fan 

trays. 

 lists the chassis air flow architecture and requirements for the Catalyst 6500 series 

switches. Sensors on the supervisor engine monitor the internal air temperatures. If the air temperature 
exceeds a preset threshold, the environmental monitor displays warning messages. 

The Catalyst 6500 series switch is designed to be installed in an environment where there is a sufficient 
volume of air available to cool the supervisor engines, modules, and power supplies. Any constraints 
placed on the free flow of air through the chassis or an elevated ambient air temperature can cause the 
switch to overheat and shut down.

To maintain proper air circulation through the Catalyst 6500 switch chassis, we recommend that you 
maintain a minimum 6-inch (15 cm) separation between a wall and the chassis air intake or a wall and 
the chassis hot air exhaust. In situations where the switch chassis are installed in adjacent racks, you 
should allow a minimum of 12-inches (30.5 cm) between the air intake of one chassis and the hot air 
exhaust of another chassis. Failure to maintain adequate spacing between chassis can cause the switch 
chassis that is drawing in the hot air exhaust to overheat and fail. On Catalyst 6500 series chassis in 
which the airflow is from front to back, the chassis may be placed side-to-side.

If you choose to install your Catalyst 6500 series switch in an enclosed or partially enclosed rack, we 
strongly recommend that you verify that your site meets the following guidelines:

Verify that there is a minimum of 6 inches (15 cm) of clearance between the sides of the rack and 
both the chassis air intake grill and the chassis air exhaust grill.

Verify that the ambient air temperature within the enclosed or partially enclosed rack is within the 
chassis operating temperature limits.  After installing the chassis in the rack,  power up the chassis 
and allow the chassis temperature to stabilize (approximately 2 hours). Measure the ambient air 
temperature at the chassis air intake grill and at the chassis air exhaust grill by positioning an 
external temperature probe approximately 1 inch (2.5 cm) away from the grills, in line with the 
chassis slot occupied by the supervisor engine. 

If the ambient intake air temperature is less than 40°C (104°F), the rack meets the intake air 
temperature criterion.

If the ambient intake air temperature exceeds 40°C (104°F), the system might experience minor 
temperature alarms and is in danger of overheating.

If the ambient intake air temperature equals or is greater than 55°C (131°F), the system will 
experience a major temperature alarm and shut down.

Verify that the enclosed or partially enclosed rack allows an adequate flow of air through the switch 
chassis as follows: 

If the difference between the measured intake air temperature and the exhaust air temperature 
does not exceed 10°C, there is sufficient airflow in the rack. 

If the difference in air temperature exceeds 10° C, there is insufficient airflow to cool the 
chassis. 

The 10°C temperature differential between the intake and the exhaust must be determined by 
taking measurements using external digital temperature probes. Do not use the chassis internal 
temperature sensors to measure the temperature differential.