IBM T00 - Power-Off Procedure with the DC Power Distribution Panel; Removal and Replacement of the AC Power Distribution Bus

Power-Off Procedure with the DC Power Distribution Panel
This section covers the power-off procedure for the dc rack.
1. Be sure the operating system is shut down. See “Operating System Shutdown” on page 25.
2. Turn off power to all devices and drawers in the rack. For more information, refer to the service guide.
3. Turn off power to all external devices attached to the system.
4. Unplug the device power cords from the customer’s electrical outlets.
Note: If drawers in attached racks are connected to circuit breakers in the dc power distribution panel
of this rack, power to the drawers in attached racks will be powered off if the circuit breakers in
this rack are set to off.
5. Except for circuit breakers in this rack that are connected to drawers in another rack, set all circuit
breakers to the off position (down).
CAUTION:
Energy hazard, remove power before servicing. Disconnect two power supply cords.
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Note: Because a large number of external devices can be connected to the system unit, it might be
impractical for you to turn off power to all the devices and unplug their power cords.
The following illustration shows the front view of the power distribution panel (PDP)
2
3
1
A1 B1A2 B2A3 B3
A4 B4A5 B5
A6 B6
A7
A8 A9
B7
B8 B9
1 Circuit Breaker Positions (Not labeled on PDP)
2 Down Position (Off)
3 Up Position (On)
Removal and Replacement of the AC Power Distribution Bus
This section covers the removal and replacement procedures for the ac power distribution bus. The
following illustration shows where the ac power distribution bus might be installed.
Note: If there are more than four power distribution buses in the rack, additional buses may be mounted
horizontally in the rear mounting rails of the rack.
Chapter 3. Removal and Replacement 29