Power Subsystem; Bulk Power Assembly (Bpa); Bulk Power Regulator (Bpr) - IBM pSeries 670 Service Manual

Power Subsystem

This section contains the removal and replacement procedures for the power subsystem.
Notes:
1. All pluggable BPA FRUs are replaced concurrent with system operation when the removal and
replacement instructions are followed. Exceptions to this occur when multiple failures exist in the BPA.
2. Removal and replacement of the entire BPA enclosure (BPE) is also concurrent with system operation,
unless there are multiple BPE failures.
Attention: Be sure to check for FRU redundancy to determine if the repair can be performed
concurrently. If you cannot determine redundancy, delay the repair until the system can be shut down. See
the "Hot-Pluggable FRUs" on page 781 for more specific details.

Bulk Power Assembly (BPA)

The bulk power assembly is on the top of the rack. This assembly provides power to the whole system.
There are two sides to the BPA so that power is never completely removed from the system unless the
system power is shut down, and the power cables are removed from the customer's power source.

Bulk Power Regulator (BPR)

The BPRs are located in the bottom positions of the bulk power enclosure (BPE).
Note: Before installing the BPR in the BPE (Bulk Power Enclosure) during a service or repair action, the
Lock/Unlock switch located on the BPR, MUST be set to the Unlock position. Failure to do so may
damage the BPR guide rails in the BPE resulting in extended outages and unnecessary, additional
parts replacement.
Removal
Attention: The BPR unit weighs approximately 12.47 kg (27.5 lbs).
1. Locate the BPR to be replaced.
2. Note the state of the BPR ENBL LED.
3. Press the green Start Service button on the UEPO switch.
4. Proceed only if the ENBL (Good) LED goes off or the repair has been scheduled (System outage -
UEPO off),
5. Locate the BPR to be replaced and manually slide its Lock/Unlock switch to unlock (power switch to
the right). At this point, the ENBL LEDs turn off.
6. If the integrated battery feature (IBF) is installed, manually turn off the IBF circuit breaker attached to
the BPR being repaired. Unplug the battery cable from the front face of the BPR.
7. Loosen the left and right fasteners using the torque tool (part number 6422789). Push up on the BPR
release levers, and slide the unit out of the slot.
Replacement
1. Make sure that the BPR release levers are in the UP position. Slide the unit into slot until one inch
from BPE. Using both hands on the front of the BPR, firmly and quickly seat the BPR against the
backplane.
2. Tighten the left fastener four turns with torque tool followed by four turns to the right fastener. Torque
the left fastener to completion, followed by the right fastener. Return to the left fastener and ensure
that it is properly torqued.
3. Move the BPR release levers to the DOWN position.
4. If the battery feature is installed, reconnect the battery cable to the connector on the front face of the
BPR.
5. Manually turn on the IBF circuit breaker.
Chapter 9. Removal and Replacement Procedures
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