Prime Power Transformer, Removal And Replacement; Prime Power Transformer - IBM 3274 51C Maintenance Information

4.6 Prime Power Transformer, Removal and
Replacement (Figure 4-5)
1. Place the
m /
~
(on/off) switch in the
~
position.
2. Remove the power cord plug from the building power
receptacle.
3. Open the gate (paragraph 4.2).
4. Disconnect the 13 connector
0
from the prime
power box.
5. Disconnect the wires leading to the diode assembly
e
(wires 3,4, or 7,8 or 11, 12). See Figure 4-7
(the diode assembly is identified as CR1).
Figure 4-5. Prime Power Transformer
4-6
6. World Trade countries only - Remove the fan leads
from the transformer terminal strip. Note the location
of wires for use in reassembly. See Figure B-6.
7. Remove the three hex mounting bolts
e
and remove
the transformer.
8a. U.S. and Canada only - To reinstall, reverse these steps.
8b. World Trade countries only - Reconnect the fan leads
and connect the plug P3 cable at the transformer
terminal strip, using the old transformer as a guide.
To reinstall, reverse these steps.
Warning: Verify that the starwashers are replaced between
the transformer bracket and the rear casting.
Shown for U.S. and Canada.
For World Trade, 58e Figure 8-6.