Troubleshooting Enclosure Fan Modules - Dell PowerEdge C8000 Hardware Owner's Manual

Troubleshooting Enclosure Fan Modules

CAUTION:
Many repairs may only be done by a certified service technician. You
should only perform troubleshooting and simple repairs as authorized in your
product documentation, or as directed by the online or telephone service and
support team. Damage due to servicing that is not authorized by Dell is not covered
by your warranty. Read and follow the safety instructions that came with the
product.
NOTE:
The fan modules are hot-swappable. Remove and replace only one fan
module at a time in a server enclosure that is turned on. Operating the system
without all three fan modules for extended periods of time can cause the system to
overheat. Review the following table before you begin to replace the fan modules.
Fan Module (Fan Controller Firmware) Thermal Behavior Per Sled
Table 5-1. Fan Module (Fan Controller Firmware) Thermal Behavior Per Sled
Fan Module BMC (Processor/Memory)/Server Enclosure Temperature Status
Status
OK/OK
Fan module Close loop,
normal/OK
Open loop (curve A)
If the PWM duty
cycle value rises above
100%, sled-level
throttling is
triggered
One fan Close loop,
module fails
If the PWM duty
cycle value rises above
100%, sled-level
throttling is triggered
OK/Fail
Close loop,
a
, 80% PWM
If close loop
PWM signal
value is > 80%,
the PWM
b
output will
follow the close
loop output
100% PWM
b
Fail/OK
Open loop (curve B)
If the PWM duty
cycle value rises above
100%, sled-level
throttling is triggered
100% PWM
Open loop
d
(curve C) ,
If the PWM duty
cycle value rises above
100%, sled-level
throttling is triggered
Troubleshooting
Fail/Fail
c
, 100% PWM
b
100% PWM
System
throttling
b
257