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Chapter 4: Power Supplies and Fans
4.4 Power Management
The Chassis Management Module assumes the maximum power case for each blade prior to
applying power. If the system power is not sufficient, the CMM will not allow that unit to power
up. After a blade is powered up, the blade BIOS calculates the actual power load required by
that blade based upon the installed devices and informs the CMM of its requirements. The
CMM then recalculates the remaining power for additional blades.
4.5 Cooling
Power supply modules include a system fan. If some bays in an enclosure are not filled with
power supply modules, the can house similar sized fan modules. If a power supply fails, its
fan will continue to operate to provide continuous cooling. For this reason, a failed power
supply should remain installed in the enclosure until a replacement unit is ready.
For overheating problems, check that:
•
There are no obstructions, such as poorly routed cables
•
All fans are operating normally
•
The ambient room temperature is not too warm (refer to Section A-2: Environmental Speci-
fications on page A-6 for the maximum operating temperature).
Also, either of the blade management software utilities can increase the fan speed and
maximize system cooling.
