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92026r15
V200 POSITIONER
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1.1 Principle of Operation
The V200 incorporates the force balance
principal of operation. The desired value, in
the form of pressure, affects the membrane(1)
with the force that is created and transferred to
the balance arm(2). The opposing force, which
represents the actual control value, is provided
by the feedback spring(5) and creating force in
the opposite direction on the balance arm(2).
The feedback spring, resting on the feedback
arm(3), is positioned by the shape and re-
sponse of the cam. The cam(4) is connected
to the cylinder’s (actuator) piston rod via the
drive.
The pilot valve(6) is connected to the balance
arm and follows the balance arm’s movement.
The system is stable when the gold plated
spool(7) is in the neutral position and the forces
that affect the balance arm is in equilibrium.
As soon as a signal change occurs or a change
in the position of the valve/actuator package
occurs, the “force balance” is also changed
and the spool responds. Air immediately begins
to flow into the part of the actuator (C+ or C-)
which allows the feedback mechanism to return
the spool to the neutral position.
The system is self-stabilizing and searches for a
steady state position.
1.2 Product identification
The V200 identification tags, Serial number
tag(1), product model tag(2) and feedback op-
tion tags(3), are placed as shown.
The product model tag contains information on
control signal, maximum working pressure and
temperature ranges. Other information can be
shown depending on the model.
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