BAC PCE Operating And Maintenance Instructions Manual page 23

Drive Alignment
Proper drive alignment ensures maximum belt life. Alignment is checked for standard drives after correct belt
tensioning by placing a straight-edge across both sheaves as shown in the figure below.
Sheave alignment standard drives
1. Motor sheave
2. Fan sheave
3. Points of contact
When the drives are properly aligned the straight edge will contact all four points as indicated. There should be no
more than 1,5 mm deviation from four point contact. If realignment is necessary, loosen the motor sheave and
align it with the fan sheave. Allow approximately 6 mm for draw-up as the bushing screw is re-tightened.
Locking Collar
The excentric locking collar of the bearing at the drive end ensures that the inner bearing race is secured to the fan
shaft. Locking collars can be set using the following procedure. (See figure below)
1. Stop fan(s) and remove side access panel(s).
2. Loosen the set screw.
3. Using a drift pin centre-punch, tap the collar (in the hole provided) tangentially in the direction of rotation while
holding the shaft.
4. Re-tighten the screw.
5. Close unit access door and start pump(s) and fan(s).
Locking collar assembly
1. Locking collar
2. Lubrication fitting
3. Set screw hole
ROTATION OF FAN(S) AND PUMP(S)
Fans must rotate without obstruction and both fans and pumps must rotate in the correct direction, which is
indicated by arrows on the equipment. Check proper functioning as follows:
1. Stop fan(s) and pump(s).
2. Turn the fan by hand to ensure rotation without obstruction. Remove obstruction, if present.
3. Start the pump(s) and check for the proper rotation as indicated by the arrow on the pump cover. If rotation is
wrong, stop pump and correct electrical wiring.
4. Start the fan(s) and check for proper rotation as indicated by the arrow on the fan housing. If rotation is wrong
stop fan(s) and contact BAC.
5 Maintenance Procedures
5 Maintenance Procedures
W W W . B A L T I M O R E A I R C O I L . E U
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