Dresser Masoneilan 4700E, Instructions Manual

Instruction ES2007 4/98
Models 4700P and 4700E

20

2.

With cam at low signal line remove screw (28) and
washer (27). Note the relative position of the cam
lobe being changed and then remove the cam (26).

3.

Select the desired cam lobe and replace cam (26)
on cam shaft with low signal line of desired lobe
against cam follower. Ensure the newly selected cam
lobe is in the same relative position as the lobe noted
in Step 2.

4.

Replace washer (27) and screw (28). Check zero and
span adjustment. (Refer to zero and span adjustment
section).

Air to Close/Reverse Acting Positioner (Figure 19)

1.

Shut off supply pressure and signal to positioner.
Valve is now open and cam (26) is at high signal line
on lobe. Do not remove.

2.

Run an independent regulated air line to the valve
actuator in place of positioner output line.

Slowly apply proper air pressure through the regula-
tor to shut the valve. Do not exceed designated
supply pressure. (Handwheel may be used to close
the valve in place of regulated air line.) Align the travel
indicator with the “closed” end of travel scale. Cam is
now at low signal line on lobe.

3.

With cam at low signal line remove screw (28) and
washer (27). Note the relative position of the cam
lobe being changed and then remove the cam (26).

4.

Select the desired cam lobe and replace cam (26)
on cam shaft with low signal line of desired lobe
against cam follower (4A). Ensure the newly selected
cam lobe is in the same relative position as the lobe
noted in Step 3.

5.

Replace washer (27) and screw (28). Reduce pres-
sure applied in Step 2 to zero (back off the handwheel
if handwheel was used). Disconnect the independent
regulated air line to actuator and connect positioner
output line. Connect supply pressure and signal to
positioner. Check zero and span adjustment. (Refer
to zero and span adjustment section.)

Field Mounting and Complete
Calibration, Rotary Actuators

The following instructions are to be followed for mounting
and calibration of the 4700P and 4700E positioner. Define
the proper valve action and positioner action. If the posi-
tioner is not on the valve, see Figure 20 to mount positioner
and cam coupling. Once the positioner body is assembled
on the valve and the coupling is on the valve shaft, proceed
to the proper section below.

Air to Open/Direct Acting Positioner (Figure 19 & 20)

1.

Do not connect air supply or signal to the positioner.
Valve is closed.

2.

Place lever S/A (3) to proper side (left or right) as
designated by the appropriate cam selection table for
valve in question.

3.

With valve closed, place cam holder (36) with truarc
ring (37) into cam coupling (34).

4.

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 to cam holder with washer
(27) and screw (28). Tighten the screw (28) while
holding the cam (26).

5.

With the valve closed, 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 refer-
ence 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 for cam mounting.)

6.

Connect air supply and signal to positioner. Connect
positioner output to valve actuator. Refer to connec-
tion diagram. Adjust signal to low end of signal
(i.e., 3 psig for a 3-15 psig range 4700P; 4 mA for
4-20 mA 4700E).

7.

Adjust zero and span. (Refer to zero and span adjust-
ment section.)

Air to Open/Reverse Acting Positioner (Figure 19)

1.

Do not connect air supply or signal to the positioner.
Valve is closed.

2.

Place lever S/A (3) to proper side (left or right) as
designated by the appropriate cam selection table for
valve in question.

3.

Run an independent regulated air line to the valve
actuator in place of positioner output line. Slowly
apply proper air pressure through the regulator to
open the valve. (Handwheel may be used to open the
valve in place of regulated air line.) Align the travel
indicator with the “open” end of travel scale. Do not
over travel.

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