Compaq BL10e - HP ProLiant - 512 MB RAM Introduction Manual page 23

• An over-provisioned CRAC unit (large negative percentage) operates significantly below the
capacity of the unit. This results in wasted energy if operation of the unit cannot be adjusted to
match the lower cooling load.
For example, Figure 18 shows the row-wise distribution of heat loads (41 kW to 182 kW) for a
combination of compute, storage, and networking equipment in a typical raised floor data center with
four CRAC units. The CFD model shows that the provisioning of the CRAC units is completely out of
balance.
Figure 18. Poorly provisioned CRAC units
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