Nortel 7400 Hardware Installation page 431

disengage the air filter assembly. Pull the air filter assembly out of its slot.
See the figure "Removing the air filter assembly from a Multiservice
Switch 7480" (page 496).
5 Remove all cables from the cable management unit.
6 Use a 5/16-in. socket wrench to remove the four screws that fasten the
cable management unit to the frame. See the figure "Multiservice
Switch 7480 cable management assembly" (page 290). Remove the
cable management assembly.
7 Use a 5/16-in. socket wrench to remove the eight screws that secure the
shelf assembly to the frame. See the figure "Multiservice Switch 7480
shelf assembly" (page 289). With the assistance of a second person,
remove the shelf assembly.
8 Use a 5/16-in. socket wrench to remove the four screws that secure the
cooling unit chassis to the frame. Remove the cooling unit chassis. See
the figure "Multiservice Switch 7480 cooling unit chassis" (page 288).
9 Pack all shelf components in their original packaging.
Multiservice Switch 7400 Hardware Installation, Maintenance, and Upgrade 6.1S2
Chapter 39 Hardware procedures 431