Dell Precision R5400 (Mid 2008) - Manual (Page 11)

Rack Installation Guide
9
Removing the Rack Doors
See the procedures for removing doors in the documentation provided with your rack cabinet.
CAUTION:
Because of the size and weight of the rack cabinet doors, never attempt to remove or install them
by yourself.
CAUTION:
Store the doors where they will not injure someone if the doors accidently fall over.
Marking the Rack
For a 2-U system, you must allow 2 U (88 mm, or 3.5 inches) of vertical space for each system you install
in the rack.
Rack cabinets that meet EIA-310 standards have an alternating pattern of three holes per rack unit with
center-to-center hole spacing (beginning at the top hole of a 1-U space) of 15.9 mm, 15.9 mm, and 12.7 mm
(0.625 inch, 0.625 inch, and 0.5 inch) for the front and back vertical rails (see Figure 1-2). Rack cabinets may
have round or square holes.
NOTE:
The vertical rails may be marked by horizontal lines and numbers in 1-U increments. If you want, you can
make a note of the number marking on the rack’s vertical rail. It is not necessary to mark or place tape on the rack.
Figure 1-2. One Rack Unit
CAUTION:
If you are installing more than one system, install the mounting rails so that the first system
is installed in the lowest available position in the rack.
1 U (44 mm [1.75 inches])
12.7 mm (0.5 inch)
15.9 mm (0.625 inch)
15.9 mm (0.625 inch)
12.7 mm (0.5 inch)