Chapter 3
Installation Guidelines
13
Figure 3-3. Attaching Rear Tie-Downs to Rail
Stability
For stability, the sum of the moments above the 32 U critical height must be less than the sum of
the moments below the 32 U critical height. As long as the weight above critical height is less
that the weight below, the moments will most likely cancel. The center of gravity of the cabinet
itself is well below the critical height, adding stability. Because the racks are deeper than they
are wide, they are more stable from front to back, than side to side, as shown in Figure 3-4.
X’
W
X
Y
11.0
Vertical axis 10 degrees
Z
1.25m 25U
1.6m 33U
1.96 m 41 U
62.4” 32U
Critical
height
Figure 3-4. Critical Height
TAN 10 degrees = 11.0 / Z
Z = 11.0 / TAN 10 degrees
Z = 62.4 in ( 1.58 m)
