Service manual

Power Cabinet Component Removal and Replacement 5-35
If an AC input box failed, QBBs in one of the system cabinets are not operating.
If your system is a partitioned GS320, some of the system may remain running
during this repair.
Removal
1. If the system is partitioned such that you can continue to run partitions in
the system cabinet not affected by the target AC input box, continue to let
them run. Otherwise, shut down the operating system and turn off the
machine.
2. Open the front and rear doors of the power cabinet.
3. Trip the main circuit breaker on the target AC input box.
4. Unplug the main power cord from the utility power service.
5. Unplug the power cords leading to power subracks, PCIs, and storage
devices. Note the location of all power cords. To gain access to the back of
the AC input box you may have to move to the front of the power cabinet
and remove the plastic filler guards at the bottom of the cabinet. To remove
the filler, pinch the plastic snaps at both ends of the guard and pull it away
from the frame.
6. Loosen the Phillips head screw holding the right side of the cable keeper
arm on the frame of the power cabinet just below the AC input boxes. (The
main power cable goes under it.) Swing the arm away from the frame.
7. Remove the four Phillips head screws holding the AC input box(s) to the
frame and slide the box out of the cabinet.
Replacement
1. Color-code the AC input box you are installing to replicate the one you are
replacing. Appendix A describes how power cords are configured.
2. Reverse the steps outlined in the removal procedure.
Verification
Power on the system.
Be sure to put the circuit breaker in the On position before you
put the OCP switch in the On position.