3660 and 3661 Positioners
Instruction Manual
Form 5265
March 2006
21
28B0006-B / DOC
INCREASE
TRAVEL
Figure 19. Adjustment Locations (Equivalents of Pressures Shown in This Drawing
are: 6 bar = 86 psig, 4 bar = 58 psig, and 1.4 bar = 20 psig)
Note
To improve holding of the calibration
tool as used in step 6, the actuator
may be used to create the load
(manual pressure) by winding up the
positioner range spring. The direction
of windup, looking at the spring from
outside the housing, must be
clockwise. This windup will create a
torsional force over the input
diaphragm through the lever
assembly. The spring is automatically
wound up in two of the
positioner/actuator mounting
positions when the loading pressure is
removed. These are left-hand
mounting on a spring-to-close
actuator and right-hand mounting on a
spring-to-open actuator (refer to figure
2). In the other two mounting
positions, the actuator must be
pressurized to 100 percent input to
create the spring holding force.
6. Remove the calibration tool (key 6) from the
cover. Place the calibration tool between the lever
assembly (key 17) and the input diaphragm
assembly (key 28). When making the following
adjustment, apply manual pressure to the lever
assembly over the input diaphragm assembly to hold
the calibration tool in place. Loosen the lock nut (key
57), and turn the adjusting screw (key 18) until the
output is 50%
±
10% of supply pressure. For
example, if supply pressure is 2.4 bar, set the output
to 1.2 bar
±
0.24 bar.
7. Lock the adjusting screw (key 18) with the lock
nut (key 57). After the adjustment is complete,
remove the calibration tool and replace it in the
positioner cover.
