IBM RS/6000 SP, Maintenance Information

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MAP 0550: Dependent Node
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1-351
MAP 0560: Block Multiplexer Channel Adapter (BMCA)
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1-353
MAP 0570: End of Call
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1-357
MAP 1520: Main Power
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1-359
MAP 1540: Minimum Configuration
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1-360
This chapter provides information for identifying problems and guides you to the most likely failed Field
Replaceable Unit (FRU). The MAPs then refer you to the FRU Removal/Replacement procedures for the
corrective action.
Safety Notices
The following practices are necessary to ensure safety of all service personnel while servicing this
machine.
Lockout Procedures
Lockout Procedure for SEPBU
This procedure ensures that no power is present in the machine, and that primary power can not be acci-
dentally applied. This procedure is referenced as required by the maintenance procedures.
1. Make sure the main power switch is in the Off (‘0’) position for this frame.
2. The following measurements are to be taken at the ac filter (located inside the rear cover at the
bottom of the frame). Measure phase-to-phase ac voltage between test points Z1 and Z2. Repeat
measurement for test points Z1 and Z3. Repeat measurement between test points Z2 and Z3.
3. The purpose here is to guarantee that initially primary power is present at the test points. If the volt-
ages measured in Step 2 indicate that primary power is not present, have customer switch on power
for this frame, then go back to Step 2.
4. Continue with Step 5 of “Lockout/Tagout Procedure for PDU” or “Lockout/Bagout Procedure for PDU”
on page 1-3.
Note: Be sure that the ac line cord is disconnected from the customer's main power outlet before
attaching the cord to the SEPBU.
Lockout/Tagout Procedure for PDU
This procedure ensures that no power is present in the machine, and that primary power can not be acci-
dentally applied. This procedure is referenced as required by the MAPs.
1. Use a multimeter with the pair of high-voltage probes (part number 93F2731). Set the multimeter to
the highest ac voltage setting.
2. The following measurements are to be taken at the ac filter (located inside the rear cover at the
bottom of the frame). Measure phase-to-phase ac voltage between test points O1 and O2. Repeat
measurement for test points O1 and O3. Repeat measurement between test points O2 and O3.
3. The purpose here is to guarantee that initially primary power is present at the test points. If the volt-
ages measured in Step 2 indicate that primary power is not present, have customer switch on power
for this frame, then go back to Step 2.
4. Switch off frame circuit breaker (located inside rear cover near bottom) to disengage ac power inside
frame.
1-2
RS/6000 SP MAPs