Service manual

GS80 Component Removal and Replacement 6-7
Before you open the drawers to remove FRUs in a bottom drawer, follow instructions
regarding the operating and power state associated with the removal and replacement of
the particular FRU.
It is possible, in a nonstandard configuration, that two drawers are configured as two
totally independent systems with no distribution board. If this is the case, treat the two
drawers as single drawers.
1. Open the front and rear doors.
2. At the rear, unscrew the two captive screws holding the distribution board channel to
the bottom drawer.
3. At the front, remove the eight Phillips head screws holding the drawers to the cabinet
frame.
4. Pull both drawers forward on their rails until they stop. (This lock can be released by
pushing buttons below the stops should you need to remove the whole box.)
5. At the left side of both the top and bottom drawer toward the rear, remove the
distribution board channel covers. Two Phillips head screws hold each cover in place.
6. Unplug the two global port cables from the bottom of the distribution board and fold
them toward the front of the bottom drawer.
To disconnect the cables, insert the
blade of a flathead screwdriver between the plastic cable guide and the lip of the
connector at one end. Twist the screwdriver so that one edge of the cable rises from the
connector. Repeat this procedure on the other edge of each cable, pull the cable from
the connector, and fold it toward the front of the bottom drawer.
7. Unplug the 48V power cable and fold it out of the way.
8. The coax clock cable is looped inside the distribution board channel in the upper
drawer. Release the loop from its clamp and thread the excess cable down from the
top drawer to the bottom so that the top drawer can slide back into the cabinet
without putting strain on the cable.
Note when recoiling this cable, the loop
should not have a diameter smaller than 3.5 inches (9cm).
9. Replace the top distribution board cover that you removed in step 5 and carefully push
the top drawer, now free of the bottom, back into the cabinet while attending to the
clock cable and the disconnected global port cables so they are not damaged.
10. Unscrew the two captive screws that hold the cover to the bottom drawer, tilt the
cover up, and remove it. The QBB compartment of the bottom drawer is now exposed.
Note that the safety stabilizer foot is long enough to prevent the cabinet from tipping over
when the drawers are pulled out.