IBM System/34 Maintenance Manual page 85

New Style Motor Replacement
Note: If a new style motor is installed in place of an old
style motor, the motor pivot must be removed.
DANGER
CB1 must be off to remove AC voltage from ACTB3
and ACTB4.
1. Ensure that the two plastic insulating bushings.
are installed in the motor pivot holes of the
subframe casting and the motor mounting plate.
2. Set the motor on the pivot pointand slide it into
position.
3. Install the plastic insulating washer
0,
flat
washer, lock washer, and nut on the pivot at the
back of the subframe. Tighten the nut until the
lock washer is just flat,· then unscrew the nut
one-half turn.
CAUTION
New style and old style motor tension springs are
not the same. The new style spring must be used
with the new style motor. The old style spring
must be used with the old style motor. The part
number is on the new style spring.
4. Lift the loop end of the tension spring into place
on the motor mounting bracket
O.
5. Pivot the motor against the springs to ensure
correct position of the spring loop and roller
e.
6.
Install the motor wires on ACTB3 lower drive, or
ACTB4 upper drive • - terminal 1 (black wire),
terminal 2 (white wire), and terminal 3
(green/yellow wire).
7.
8.
9.
10.
11.
12.
13.
14.
15.
16.
12
09-030
Install the brake wires on TB1 • - terminal 5
(black wire) and terminal 6 (yellow wire).
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"-
Install the safety cover on TB1 (holes to the left).
Install the cable straps
e
(if present) that hold the
brake cable.
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......
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CAUTION
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....
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Ensure that the belt does not touch the disk speed
transducer.
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1\
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. /
Lift the motor and pivot it toward the disk
enclosure and reinstall the belt
e
(smooth side of
the belt against the pulleys). Center the belt on
the pulleys.
Loosen the two screws
G
that hold the spindle
lopking arm. Slide the locking arm away from the
disk spindle.
Ensure that the antistatic brush is touching the
center of the disk spindle.
C=.'
Note: If there is a worn spot on the spindle
antistatic brush, put the spot back on the same
place on the spindle.
Tighten the screws on the spindle locking arm.
Check that the spindle antistatic brush has a
pressure of 60 (+25 to -20) grams on the center of
the disk spindle. Adjust, if necessary, by removing
and bending the brush.
Install the belt guard and tighten the two screws
G.
Slide the belt guard all the way to the left and
~
tighten the screws.
I
,
Unlock the actuator lock. by moving the handle
to OFF.
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