VAC V200E - Introduction to VAC V200 Positioner; Principle of Operation

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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,a󰀨ects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a󰀨ect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ow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 identication
TheV200identication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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