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Installing the T640 Mounting Hardware for an Open-Frame Rack


Before installing the T640 router into an open-frame rack, you must first install the large mounting shelf on the rack. If you are front-mounting the router, you must remove the center-mounting brackets from the chassis. In an open-frame rack, center-mounting is generally preferable to front-mounting because the more even distribution of weight provides greater stability. The small mounting shelf and the spacer bars are not needed.

To install the mounting hardware for an open-frame rack (see Figure 1):

  1. Install cage nuts, if needed, in the mounting holes specified in Table 1.
  2. On the rear of each rack rail, partially insert a mounting screw into the lowest hole specified in Table 1 for the large shelf.
  3. Install the large shelf on the rack. Rest the bottom slot of each flange on a mounting screw.
  4. Partially insert screws into the open holes in the ears of the large shelf.
  5. Tighten all the screws completely.
  6. Remove the mounting brackets from the chassis by loosening the screws at the top and bottom of each bracket.

The router is shipped with each spacer bar attached to the rear of each front-mounting flange. Remove each spacer bar by removing the screws that fasten the spacer bar to the front-mounting flange.

Front View of Router Chassis shows the front-mounting flanges.

Figure 1: Installing the Mounting Hardware for an Open-Frame Rack
Installing the
Mounting Hardware for an Open-Frame Rack

Table 1 specifies the mounting holes in which you insert the mounting screws (an X indicates a mounting hole location), and cage nuts if needed. The hole distances are relative to one of the standard U divisions on the rack. For reference, the bottom of all mounting shelves is at 0.04 in. (0.02 U) above a U division.

Table 1: T640 Open-Frame Rack Mounting Hole Locations


Distance Above U Division

Large Shelf


34.13 in. (86.7 cm)

19.50 U



30.63 in. (77.8 cm)

17.50 U



28.88 in. (73.3 cm)

16.50 U



25.38 in. (64.5 cm)

14.50 U



23.63 in. (60.0 cm)

13.50 U



20.13 in. (51.1 cm)

11.50 U



18.38 in. (46.7 cm)

10.50 U



17.75 in. (45.1 cm)

10.14 U