Labconco Purifie Horizontal Clean Benches 32000 Series - Manual (Page 35)

Chapter 6: Maintaining Your XT Clean Bench
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Speed Control Adjustment:
Adjusting the speed control will have an effect on the air
velocities and the effectiveness of the clean bench. Only a
qualified certification technician, as part of the recertification
process, should adjust the speed control.
Do NOT contact blower wheel while still in motion.
NE PAS être en contact avec la roué du ventilateur tant qu’il est
en marche.
1. Remove the right side prefilter only, as described on previous page.
2. Locate the speed control. It is in the electrical box mounted on the floor of the
blower housing. The speed control rheostat is just behind the small hole in the
electrical box.
3. Using a small jewelers straight blade screwdriver turn the speed control screw
clockwise to decrease the blower speed, or counter-clockwise to increase the
blower speed as shown in Figure 6-2.
4. After completing the speed control adjustment, establish the average air
velocity, using a calibrated thermal anemometer with an accuracy of ± 3%.
Establishing a boundary of 6 inches from the sides, top and bottom, measure
the velocities in 6-inch increments, 6 inches in front of the diffuser. This
methodology is more fully defined in the IEST recommended practice #IEST-
RP-CC0002.2
5. The average velocity should be 65 ± 10 FPM, with all measured values falling
within ± 20% of the average.
6. Reinstall the prefilters.
Figure 6-2
!
Speed
Control
Adjustment
Electrical
Box