STEM IS
FLUSH
WITH BODY
STEM POSITION AT
BALANCE CONDITION
Figure 4-5. Pilot Valve Adjustment
⁄
2. Use a
-inch Allen wrench (the wrench must be at least
3
32
5-inches long) to turn the lower adjustment screw clockwise the
same amount as the top adjustment screw to insure speed of
operation is the same in both directions (if desired). Be careful
when accessing the lower adjustment screw. Insert the Allen
wrench up through the bottom of the range spring (Fig. 4-6). This
adjustment controls the amount of air going to port 02.
NOTE: To adjust the pilot valve stroke to the factory setting, refer
to
PILOT VALVE STROKE ADJUSTMENT
3. Test for satisfactory stroke time and adjust as required.
TOP ADJUSTMENT SCREW
ALLEN WRENCH
ACCESS
Figure 4-6. Speed Adjustment Screws
0.030
0.030
STEM POSITION TOP
STEM POSITION LOWER
ADJUSTMENT SCREW
ADJUSTMENT SCREW
in
Section
SIGNAL
DIAPHRAGM
HINGE SPRING
LOWER ADJUSTMENT
SCREW
RANGE SPRING
GAIN AND SPEED ADJUSTMENTS
CALIBRATION
T00777A
8.
T00778A
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