Daikin RDT-135c Installation And Maintenance Manual page 109

MVP Variable Pitch Sheaves
Adjusting:
1 Slack off belt tension by moving the motor toward the
driven shaft until the belts are free from the grooves. For
easiest adjustment, remove the belts.
Loosen both locking screws A in outer locking ring, but do
2
not remove them from the sheave. There is a gap of
approximately 1/2" (1 mm) between the inner and outer
locking rings. This gap must be maintained for satisfactory
locking of the sheave.
If locking screws A are removed by accident and the gap is
lost, screw the outer locking ring down until it touches the
inner locking ring. Then back off the outer ring 1/2 to
3/4 turn until the inner and outer ring screw holes line up.
Reinsert locking screws A, but do not tighten them until
after adjustment is made.
Figure 110. LVP variable pitch sleeves
A
e c t i o n A - A
Figure 111. MVP variable pitch sheaves (type A-B)
IM 738-2
Check, Test, and Start Procedures: Mounting and Adjusting Motor Sheaves
A
E
E
.
D
D
e c t i o n A - A
Adjust the sheave to the desired pitch diameter by turning
3
the outer locking ring with a spanner wrench. Any pitch
diameter can be obtained within the sheave range. One
complete turn of the outer locking ring will result in a
0.233" (6 mm) change in pitch diameter.] Do not open
A–B sheaves more than four 3/4 turns for A belts or 6
turns for B belts. Do not open C sheaves more than nine
1/2 turns.
Tighten both locking screws A in the outer locking ring.
4
Put on the belts and adjust the belt tension. Do not force
5
belts over grooves. Loosen the belts by adjusting the motor
base closer to the fan shaft.
Do not loosen any screws other than the two locking screws (A)
in the outer locking ring. Before operating the drive, securely
tighten these screws.
E
A
.
D
B
CAUTION
A
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