Flowserve APEX 8000 High-Performance Positioner - Manual (Page 6)

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.
Figure 4: Positioner Adjustments
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 out put
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 pres sure level, follow the procedure outlined:
1. If output pressure level is low, before adjusting, check for leaks in tubing connections between positioner and actua tor and check supply
pressure.
2. Make certain there is no process force or pressure in the valve (The valve should be removed or isolated from the process.)
3. On positioners without gauges, connect gauges to ‘output 1’ and ‘output 2’ lines.
4. Remove rubber cap over balance adjustment screw. (See Figure 4.)
5. Apply full actuator operating pressure to positioner supply port.
Apex 8000 High-Performance Positioner AXENIM0130-06 11/10
6
Zero Adjustment
Knob Span Adjustment Feedback Spring
Arm
Span Adjustment
Locking Screw
Mouting Holes for
Internal Electronics
Cam
Orifice Screw Cam Spring
Output 1
Zero Adjustment
Lock Knob
Cam Follower Arm
(Range Arm)
Output 2
(Shown Plugged)
Balance
Adjusting Screw
Feedback
Spring
Pilot Relay
Assembly
I/P Transducer