The chassis has a front-to-rear airflow. All of the power supplies and fan modules in the chassis must use the
same airflow direction or an error will occur with possible overheating and shut down of the controller. If you
power up the controller with more than one airflow direction, you must power down the controller and replace
the modules with the wrong airflow direction before powering up the controller.
Caution
Power Supply LEDs
The following table describes the power supply LEDs.
Table 7: AC Power Supply LEDs
Amber (FAIL) LED
Status
Green (OK) LED
Status
Power Supply Condition
OFF
OFF
No AC power to all power supplies
ON
OFF
Power Supply Failure (includes over voltage, over current,
over temperature and fan failure)
1Hz Blinking
OFF
Power Supply Warning events where the power supply
continues to operate (high temperature, high power and slow
fan)
OFF
1Hz Blinking
AC Present/3.3VSB on (PSU OFF)
OFF
ON
Power Supply ON and OK
Power Supply Fans
The fans in the power supply module are used for cooling the power supply module itself while system-level
cooling is provided by fans within the chassis. The power supplies do not depend on the system-level fans
for cooling. Fan failure is determined by fan-rotation sensors.
The fans in the Cisco Catalyst 9800-80 Wireless Controller power supplies have plug-side intake airflow.
Note
The chassis has a front-to-rear airflow. All of the power supplies and fan modules in the same chassis must
use the same airflow direction or an error will occur with possible overheating and shut down of the controller.
If you power up the controller with more than one airflow direction, you must power down the controller and
replace the modules with the wrong airflow direction before powering up the controller.
Caution
The fans in the power supply modules will run as soon as the power supply is plugged in, even if the power
switch is in the Standby position.
Note
Cisco Catalyst 9800-80 Wireless Controller Hardware Installation Guide
16
Supported Hardware Components
Power Supply LEDs