Rackable Systems OmniStor 4900F Series, User Manual, Page: 143 / 196

Chapter 4 - Managing and Monitoring
Manual Override
129
When this option is enabled, the software will control the RPM of the cooling fans
based on enclosure temperature parameters and its installed component.
For example, if any one or a combination of the following occurs, the cooling fan
RPMs will be set to the maximum software controlled RPM: a disk drive is removed
from any of the drive slots 4 through 9, a power supply is removed, one of the
cooling fans in the cooling fan module fails, a temperature sensor fails, or a SES
processor fails.
Manual Override
A manual override of the fan speed control is available for special circumstance
environments. Referring to the illustration on the following page, two jumpers are
provided on the fan module printed circuit board to override the firmware control of
the fan speeds.
This hardware setting provides full voltage to the fans for maximum operational
speed, which is greater than the maximum speed set by the automatic software
control. This configuration is normally used when fan speed noises are not an issue,
and the ambient operating temperature is at or above 30°C (86°F), thus ensuring that
maximum available cooling is being provided.
Cooling Fan Module