Align and slide the two pieces of the Base Module's rail together.

1. Position the front rail with the rail tabs toward the outside of the rack.
2. Slide the front rail toward the back rail to engage the tabs of the front rail.
3. Push the front rail into the rack until the front edge of the rail is approximately 60 mm (2.4 inches) from the rack stile.

   Figure 2-5 Front Rail Installation (Left Rail Shown)

   

   • Illustration Legend:
   • 1 - Back Rail
   • 2 - Front Rail

Use the mounting block and screws to secure the front rail to the rack.

1. Position the mounting block behind the rack stile in the second U of the three U span. See Figure 2-6. You might need to flex the front of the rail away from the rack stile while positioning the mounting block.

   Figure 2-6 Mounting Block for Front Rail (Right Rail Shown)

   

   • Illustration Legend:
   • 1 - First U
   • 2 - Second U
   • 3 - Third U
2. Hold the block in position. Push the front rail against the rack stile.
3. Insert the 8–32 screw through the hole in the front rail and thread the screw by hand a few turns into the mounting block.
4. Tighten the 8–32 screw with a Phillips screwdriver while making sure that the rail is plumb with the inside edge of the rack stile.

   Note:

   The front rail should not tilt in or out.

5. Repeat to install other front rail on the other side of the rack

The rails must be parallel and properly installed before mounting the Base Module.

1. Verify that the rack rails are parallel with each other. See Figure 2-7. If they are not parallel, reinstall the rails. Do not proceed unless the rails are parallel.
2. If your rack has threaded holes, proceed to Mount the Base Module.

   Figure 2-7 Rails Installed - Front View

   

Racks with square holes require a clip nut and a 10–32 X 5/8 screw. The square clip nut is placed on the inside of the rack stile.

Figure 2-8 Clip Nut Location for the Base Module

• Illustration Legend:
• 1 - First U
• 2 - Second U
• 3 - Third U
• 4 - Clip Nut in the Second Hole of the Third U

1. Locate the hole immediately below the front rail (second hole in the third U).
2. Seat one edge of the clip nut into the hole from the rear of the rack stile.

   Tip:

   For better access to compress the spring, position the clip nut tabs horizontally and seat the edge toward the outside of the stile. See Figure 2-8, callout 4.

3. Compress the other edge of the clip nut and seat it in the hole. A small flat blade screwdriver can simplify the compression.
4. Repeat for each front rail.