IBM T00 Service Manual page 40

2. Using a polarity-sensitive multimeter, ensure that the voltage and polarity are correct at the dc power
distribution panel (check both the -48 V dc bus and the -48 V dc return bus) as follows:
a. Ensure that all circuit breakers are off (circuit breaker switches in the down position).
b. Measure for -40 V dc to -60 V dc between position 1 (-) and position 2 (+) on terminal board 2 to
test the power for side A.
c. Measure for -40 V dc to -60 V dc between position 5 (-) and position 6 (+) on terminal board 2 to
test the power for side B.
The following illustration shows the front view of the power distribution panel (PDP)
1
3. Plug all externally attached device power cords into customer's the electrical outlets.
4. Turn on power to all external devices attached to the system unit. For more information, refer to the
service guide.
5. Set all the circuit breakers to the on position (up).
6. Turn on power to all of the devices and drawers connected to the dc power distribution panel.
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7014 Model T00, and Model T42 Service Guide
1 2
3 4
1
1 Power Status Connections for Side A Circuit Breaker
2 Power Status Connections for Side B Circuit Breaker
A1 A2 A3 A4 A5 A6 A7 A8 A9
2
1 Circuit Breaker Positions (Not labeled on PDP)
2 Down Position (Off)
3 Up Position (On)
5 6
7 8
2
B1 B2 B3 B4 B5 B6 B7 B8 B9
3