IBM RS/6000 H50, Installation And Service Manual

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Step 1520-10
Check that the power outlet is properly wired and is providing the correct voltage.
Did you find a problem?
NO Go to “Step 1540-1” on page 2-26.
YES Correct the problem. Go to "MAP 410: Repair Checkout" in the
Diagnostic Information for Multiple Bus Systems.
Step 1520-11
Since the 7026-H50 can have redundant power supplies, it is not necessary to power
down the system in order to replace a power supply. The power supplies are sym-
metrical so replacement starts with the left-hand unit (Power Supply 1). The excep-
tion to this rule is if the green LED on the back of one of the power supplies is either
blinking or not lit. In this case start with that power supply. See “Power Supplies and
Power Supply Fan Assemblies” on page 7-19 for instructions on replacing a power
supply. Before removing a power supply be sure the "other" power supply is opera-
tional by observing the green LED, which should be lit. Also be aware that the
power supply exchange process must be completed within 5 minutes, including
moving the fan assembly from the removed supply to the replacement power supply.
After five minutes, the Service Processor shuts the system down to avoid over-
heating devices in the Media and DASD bays.
Replace the following FRUs in order:
1. Power Supply 1.
2. Power Supply 2.
Perform Error log Analysis.
Do you receive an SRN indicating a Voltage Sensor out of range?
NO The last FRU exchanged is defective. Go to "MAP 410: Repair Checkout"
in the
Diagnostic Information for Multiple Bus Systems.
YES Reinstall the original FRU.
Repeat the FRU replacement steps until a defective FRU is identified or
all the FRUs have been exchanged.
If the symptom did not change and all FRUs have been exchanged go to
“Step 1520-12” on page 2-19.
2-18
RS/6000 Enterprise Server Model H50 Installation and Service Guide