IBM 7014 T00, Manual

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10. After the -48V DC B power sources are turned off, be sure there is a tag or label over the B power
source switch or fuse (lock-out/tag-out) to indicate that the B power source has been turned off
intentionally.
11. Remove the B side plastic bus bar covers from the PDP by removing the two retaining screws from
the B side cover.
12. Disconnect the DC power cable for power supply 2 (B) from the PDP. To disconnect the DC power
cable, do the following:
a. Disconnect the -48V DC wire from the circuit breaker lug on the B side. Reinstall the nuts and
washers onto the studs.
b. Disconnect the -48V return wire from the position matching the circuit breaker position on the
PDP return. For example, if the -48V DC wire was connected to circuit breaker B3, the return wire
should be disconnected from the B3 position on the return bus bar. Reinstall the nuts and
washers onto the studs.
c. Disconnect the ground wire to the matching position on the copper ground bar. Reinstall the
screws and washers into the copper ground bar.
d. Disconnect the DC power cable from power supply 2 (B) and remove it.
e. If there are additional units or power supplies to be disconnected from the B side of the PDP
repeat “12” on page 43.
13. After all the B side cables are removed, replace the B side plastic cover by repositioning the cover
over the B side connections and reinstalling the two retaining screws.
14. Replace the PDP top cover by repositioning the top cover on to the PDP and installing the four
retaining screws.
15. Install the cable channel cover. To install the cable channel cover, do the following:
a. Position the cover over the retaining screws and align the larger openings in the cover with the
retaining screw heads.
b. Set the cover down over the retaining screws and slide the cover toward the rear of the rack, so
that the screws are now located in the narrow slots.
c. Tighten the 4 retaining screws.
16. Restore the -48V DC B-side power to the PDP.
17. Use the instruction manual that came with the device to complete the removal of the device.
18. If you are cabling a new device, see “Connecting the system component power to the PDP” on page
34.
Powering on the DC-powered system components
This section provides information about how to power on the DC-powered system components.
About this task
Attention: Depending on the device there may or may not be a power on switch/button so care
should be taken when placing the device circuit breakers in the “on” position. If the device does
not have a power on switch/button the device will power on as soon as the device circuit breaker is
placed in the “on” position.
Note: There may be devices installed that only use either the A or B side circuit breaker to control the
devices power.
Note: Use the device installation manual and connect any signal cables required prior to powering on the
device.
To power on the DC-powered system components, do the following:
Procedure
1. Switch the device's A-side circuit breaker to the on position.
Racks and rack features 43