1. For 3-15 or 3-9 psi range, loosen by hand the zero adjustment locking knob and adjust the zero adjustment knob until
the valve begins to stroke with more than 3 psi signal (for 9-15 psi range adjust to 9 psi).
2. Loosen the span adjustment locking screw no more than 1/8 turn.
3. With a phillips screwdriver adjust the span adjustment so valve is at full stroke with more than 15 psi for 3-15 or 9-15
psi range (adjust to 9 psi for 3-9 psi range).
4. Return to 3 psi (or 9 psi for 9-15 psi range) and check the zero. Repeat steps 1-4 if necessary
5. Tighten the zero adjustment lock knob and span adjustment locking screw.
6. Use the same procedure for three-way split range.
7. Connect Cam return spring. See Figure 4.
Positioner Balance Adjustment
CAUTION: Balance pressure is 75 percent of the supply pressure and is the average pressure of output ports 1
and 2. Balance is preset at factory. However, if this adjustment becomes necessary, carefully make this
adjustment slowly, allowing the positioner to stabilize. Check after a short while to make sure balance pressure
is correct.
Balance adjustment is set at the factory and should not need adjustment. Balance adjustment (output pressure level)
permits the equilibrium pressure in both sides of the actuator piston to be raised or lowered. The average actuator
pressure level of output 1 or 2 is approximately 75 percent of supply pressure. For single-acting actuators, the balance
pressure should be left at the factory setting. If it is necessary to adjust the output pressure level, follow the procedure
outlined:
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