Western Digital Re EX800M, Technical Reference Manual, Page: 15 / 60

EX800M Specifications
2679-771339-A05 RELEASED 8/13/13 7
2.3.1 Physical Dimensions
2.3.2 Drive Mounting
Use either the four bottom screws or at least four of the side mounting screws to rigidly support the
drive and prevent vibration. Some adaptor frames may not have the mechanical design structure
capable of mounting the drive to meet the specified shock and vibration requirements.
The hard drive itself does not provide electrical isolation between mounting locations and drive ground
connection. If electrical isolation is required, the system designer or integrator would be responsible for
providing a solution.
2.3.2.1 Mounting Restrictions
If your system does not support hot plugging (see “Hot Plug Support” on page 21), it must be turned
off and unplugged before installing your hard drive.
2.3.2.2 Orientation
You can mount the hard drive in the X, Y, or Z axis, depending upon the physical design of your
system. For best results, mount the drive with all four screws grounded to the chassis. If all four screws
are not used, see "Grounding" on page 7.
2.3.2.3 Screw Type and Screw Length Limitations
The hard drive should be mounted to the chassis using four 6-32 screws. Recommended screw torque
is 5 in-lb. Maximum screw torque is 10 in-lb.
2.3.2.4 Grounding
The PCBA and HDA grounds are always connected together in the drive and cannot be disconnected.
The drive mounting screws, unless intentionally isolated, will provide additional ground connections
between the HDA and the system chassis. If the drive isn't grounded via mounting screws as described
under “Hard Drive Installation” on page 44, there may be increased electrical emissions (EMI).
English Metric
Dimension Tolerance Dimension Tolerance
Height 1.028 inches MAX 26.1 mm MAX
Length 5.787 inches MAX 147.0 mm MAX
Width 4.00 inches ±0.01 inch 101.6 mm ±0.25 mm
Weight (3-disk) 1.55 pounds ±5% 0.70 kg ±5%
Weight (5-disk) 1.66 pounds ±5% 0.75 kg ±5%
CAUTION: Screws that are too long can damage the hard drive. Hard drive screw penetration
can differ between products depending upon hard drive design. WD’s minimum design criteria is
to always meet the SFF 8301 industry standard specification. The industry standard as defined in
the SFF 8301 specifies a maximum of 3 mm screw penetration, and for a minimum of 2.4 mm of
thread engagement from both the screw and the hard drive.
See Figure 2-1 for allowable fastener penetration for this product family.