IBM RS/6000 SP, Maintenance Information

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MAP 0440: Short in 48 Volts DC Power Distribution
007 (continued)
– Go to Step 008.
008
– If necessary, reconnect busbars.
– Remove the obvious short between busbars.
– Reinstall plastic cover over the busbars.
– Reinstall panel over Power Distribution Unit dc section.
– Reconnect ac power and power on system.
– Go to Step 009.
009
Possible short in dc distribution cables.
– One at a time, reconnect dc distribution cables PDU-BH-P1, PDU-BH-P2, PDU-BH-P3, PDU-BH-P4,
and PDU-BH-P5 at Power Distribution Unit.
– After each connection, check frame supervisor green LED #2 for an OFF condition, indicating a short
condition.
Are you able to reconnect all cables without indication of a short condition?
Yes No
010
– Replace the cable that caused the short condition.
– From the control workstation, turn on any bulk dc power supplies that are off.
– Check frame supervisor green LED #2 for an OFF condition, indicating a short condition.
Is there still a short condition following replacement of this cable?
Yes No
011
Problem resolved.
– Make sure all cables in Step 009 are reconnected.
– Go to “MAP 0570: End of Call” on page 1-357.
012
Short inside processor node(s) or switch assemblies.
– Disconnect this dc distribution cable from all processor nodes.
– From the control workstation, turn on any power supplies that are off.
– Reconnect the dc distribution cable to processor node(s) or switch assemblies one at a time,
checking the bulk dc power supplies for indication of a short condition.
– Check frame supervisor green LED #2 for an OFF condition, indicating a short condition.
Are you able to reconnect the cable to all processor nodes or switch assemblies without
indication of a short condition?
Yes No
013
– Remove the processor node or switch assembly causing the short condition from the frame.
– Check the 48 V dc power harness inside the processor node or switch assembly for an
obvious problem such as a chafed or broken cable.
(Step 013 continues)
Chapter 1. Maintenance Analysis Procedures (MAPs)
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