Seagate Cheetah 18XL, Product Manual

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42 Cheetah 18XL Product Manual, Rev. A
8.2 Drive orientation
The balanced rotary arm actuator design of the drive allows it to be mounted in any orientation. All drive perfor-
mance characterization, however, has been done with the drive in horizontal (discs level) and vertical (drive on
its side) orientations, and these are the two preferred mounting orientations.
8.3 Cooling
Cabinet cooling must be designed by the customer so that the ambient temperature immediately surrounding
the drive will not exceed temperature conditions specified in Section 6.4.1, “Temperature.” Specific consider-
ation should be given to make sure adequate air circulation is present around the printed circuit board (PCB) to
meet the requirements of Section 6.4.1, “Temperature.”
8.3.1 Air flow
The rack, cabinet, or drawer environment for the drive must provide heat removal from the electronics and
head and disc assembly (HDA). You should confirm that adequate heat removal is provided using the tempera-
ture measurement guidelines described in Section 6.4.1.
Forced air flow may be required to keep temperatures at or below the specified case temperatures of Table 3,
in which case the drive should be oriented, or air flow directed, so that the least amount of air flow resistance is
created while providing air flow to the electronics and HDA. Also, the shortest possible path between the air
inlet and exit should be chosen to minimize the travel length of air heated by the drive and other heat sources
within the rack, cabinet, or drawer environment.
If forced air is determined to be necessary, possible air-flow patterns are shown in Figure 18. The air-flow pat-
terns are created by one or more fans, either forcing or drawing air as shown in the illustrations. Conduction,
convection, or other forced air-flow patterns are acceptable as long as the temperature measurement guide-
lines of Section 6.4.1 are met.
Figure 18. Air flow (suggested)
Note. Air flows in the direction shown (front to back)
or in reverse direction (back to front)
Note. Air flows in the direction shown or
in reverse direction (side to side)
Above unit
Under unit
Above unit
Under unit