Air To Close / Direct Acting Positioner - GE Masoneilan 4700P Maintenance Manual

4. Place cam holder (36) with truarc ring (37) into cam coupling (34).
5. Place the cam (26) onto the cam holder (36) so that the selected cam lobe is facing
forward and will rest on the cam follower. See appropriate table for cam selection.
Secure cam (26) to cam holder (36) with washer (27) and screw (28). Tighten screw
(28) while holding the cam (26).
6. With the valve open, place the desired cam lobe's low signal line on the cam
follower (4A). With the low signal line resting on the cam follower sight across the
face of the cam to the raised reference line on the positioner case and align. (Low
signal line and reference line.) Center cam between the two arms of the lever S/A
(3) then tighten set screws (35) to 87 inch-lbs. torque. (See Figure 19 on page 68 for
cam mounting.)
7. Slowly reduce pressure applied to actuator in Step 3 to zero. (If handwheel was
used to place valve in open position, back it off completely.) Cam is at high signal
line on lobe.
8. Disconnect the independent regulated air line to actuator and connect positioner
output line. Connect supply pressure and signal to positioner.
9. Adjust signal to low end of signal (i.e., 3 psig for a 3-15 psig range 4700P/4800P).
Adjust zero and span. Refer to "Zero Adjustment" on page 48 and "Span
Adjustment" on page 48.

Air to Close / Direct Acting Positioner

See Figure 19 on page 68 and Figure 20 on page 71.
1. Do not connect air supply or signal to the positioner. Valve is now open.
2. Note the valve position. The travel indicator should be approximately aligned with
the open end of the travel scale. If not aligned, consult proper valve instruction for
travel adjustment.
3. With valve open, place lever S/A (3) to proper side (left or right) as designated by
the appropriate cam selection table for valve in question.
4. With valve open, place cam holder (36) with truarc ring (37) into cam coupling (34).
5. Place the cam (26) onto the cam holder (36) so that the selected cam lobe is facing
forward and will rest on the cam follower. Secure cam to cam holder with washer
(27) and screw (28). Tighten screw (28) while holding the cam (26).
6. With the valve open, place the desired cam lobe's low signal line on the cam
follower. With the low signal line resting on the cam follower sight across the face
of the cam to the raised reference line on the positioner case and align. (Low
signal and reference line.) Center cam between the two arms of the lever S/A (3),
then tighten set screws (35) to 87 inch-lbs. torque. (See Figure 19 on page 68 for
cam mounting.)
7. Connect air supply and signal to positioner. Connect positioner output to valve
actuator. Refer to connection diagram for valve in question. Adjust signal to low
end of signal (i.e., 3 psig for a 3-15 psig range 4700P/4800P; 4 mA for 4-20 mA
4700E/4800E). Adjust zero and span. Refer to "Zero Adjustment" on page 48 and
"Span Adjustment" on page 48.
52 | =GE Oil & Gas
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