Dell C8000 owner manual Troubleshooting Enclosure Fan Modules, 257

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	OK/Fail	Fail/OK	Fail/Fail

Fan module normal/OK

One fan module fails

Close loop,	Close loop,
Open loop (curve A)a,	80% PWM
If the PWM duty	If close loop
cycle value rises above	PWM signal
100%, sled-level	value is > 80%,
throttling is	the PWM
triggered b	output will
	follow the close
	loop output
Close loop,	100% PWM
If the PWM duty
cycle value rises above
100%, sled-level
throttling is triggeredb

Open loop (curve B)c, 100% PWM

If the PWM duty cycle value rises above 100%, sled-level throttling is triggeredb

100% PWM	100% PWM
Open loop	System
(curve C)d,	throttling

If the PWM duty cycle value rises above 100%, sled-level throttling is triggeredb

Troubleshooting

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