Installing the Wire-Form Cable Guides
90 7750 SR-a4 and SR-a8 Installation Guide
Guides are normally installed after the chassis is mounted in a rack. For EIA racks, you must 
remove two of the four rack-mount screws completely, then re-use the screws to mount the 
guides to the chassis and the chassis to the rack. If ETSI brackets are used, you can install the 
guides with the adapter brackets before you mount the chassis in the rack. 
Required tools:
• a torque driver for the cable guide screws. Refer to the rack manufacturer’s 
documentation for instructions.
• EIA rack screws (not supplied), or 12-24 screws supplied with the ETSI adapter 
brackets
To install the wire-form cable guides:
Step 1. Remove the screws in holes 1 and 3 on the left side of the chassis flange.
Step 2. Orient the cable guide so the mounting eyelets are pointing toward the chassis, as 
indicated in Figure 25. 
Step 3. Replace and tighten the two screws. Refer to the rack manufacturer’s 
documentation for instructions. See Torque Specifications for Rack Mounting on 
page 59 for more information.
Step 4. Remove the screws in holes 2 and 4 on the right side of the chassis flange.
Step 5. Orient the cable guide so the mounting eyelets are pointing toward the chassis, as 
indicated in Figure 25.
Step 6. Replace and tighten the two screws. Refer to the rack manufacturer’s 
documentation for instructions. See Torque Specifications for Rack Mounting on 
page 59 for more information.
Note: When routing cables to the sides of the chassis, the egress cables may impede the 
removal and replacement of the fan on the left or the air filter on the right. For this reason, 
left mounting the cable guide may be the preferred option, because the air filter must be 
removed frequently for inspection.