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•
Belt tension check:
–
Place a straight edge along the belt from sheave to sheave as shown in
Figure 3a
, or
use a tape measure as shown in
Figure 3b
to measure belt deflection.
–
Apply a moderate force by hand (approximately 40 lbs/275 kPa) evenly across the
width of the belt in the center of the span between the sheaves.
–
There is adequate belt tension if the belt deflects between 1/4” and 3/8” as shown
in
Figures 3a
and
3b
.
NOTE:
If belts are properly
tensioned, there should be no
“chirp” or “squeal” when the fan
motor is started.
ATTENTION:
Check to ensure the
controls for the fan motor are set
to allow a maximum of six on-off
cycles per hour to prevent motor
overload.
Figure 3a.
Belt Tension with a Straight Edge
Figure 3b.
Belt Tension with a Tape Measure
•
Belt tension adjustment (if required):
–
Loosen the lock nut on the motor base adjusting screw.
–
Turn the motor base adjusting screw clockwise to
tension the belt or counterclockwise to relieve belt
tension. During adjustment of the belt tension, rotate
the drives several times by hand to evenly distribute
the tension throughout the belt.
–
When the belt is properly tensioned, retighten the
locking nut on the motor base adjusting screw.
•
Drive alignment check and adjustment:
–
Check the drive alignment annually to ensure
maximum belt life.
–
Place a straight edge across the driver and the driven
sheaves as shown in
Figure 4a
for standard drives and
in
Figure 4b
for the BALTIGUARD™ Fan System or the
BALTIGUARD PLUS™ Fan System.
–
The straight edge should contact all four points as
shown in
Figure 4a
indicating that the drives are
properly aligned.
–
There should be no more than 1/16” deviation from
the four points of contact.
–
In case of realignment, loosen the motor sheave, and
align it with the fan sheave. Allow 1/4” for draw-up as
the bushing screw is retightened.
Figure 4a.
Standard Drive Alignment
Figure 4b.
BALTIGUARD™/BALTIGARD PLUS™ Fan System Drive Alignment