42
Cheetah 15K.7 SAS Product Manual, Rev. A
If forced air is determined to be necessary, possible air-flow patterns are shown in Figure 10. 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 10.
Air flow
9.3
Drive mounting
Mount the drive using the bottom or side mounting holes. If you mount the drive using the bottom holes, ensure
that you do not physically distort the drive by attempting to mount it on a stiff, non-flat surface.
The allowable mounting surface stiffness is 80 lb/in (14.0 N/mm). The following equation and paragraph define
the allowable mounting surface stiffness:
where K is the mounting surface stiffness (units in lb/in or N/mm) and X is the out-of-plane surface distortion
(units in inches or millimeters). The out-of-plane distortion (X) is determined by defining a plane with three of
the four mounting points fixed and evaluating the out-of-plane deflection of the fourth mounting point when a
known force (F) is applied to the fourth point.
9.4
Grounding
Signal ground (PCBA) and HDA ground are connected together in the drive and cannot be separated by the
user. The equipment in which the drive is mounted is connected directly to the HDA and PCBA with no electri-
cally isolating shock mounts. If it is desired for the system chassis to not be connected to the HDA/PCBA
ground, the systems integrator or user must provide a nonconductive (electrically isolating) method of mount-
ing the drive in the host equipment.
Increased radiated emissions may result if you do not provide the maximum surface area ground connection
between system ground and drive ground. This is the system designer’s and integrator’s responsibility.
Above unit
Under unit
Note.
Air flows in the direction shown (back to front)
or in reverse direction (front to back)
Above unit
Under unit
Note.
Air flows in the direction shown or
in reverse direction (side to side)
K x X = F < 15lb = 67N
