Using The Positioner As A Process Controller - Burkert 8630 Operating Instructions Manual

3.2.2 Using the positioner as a process controller (Fig. 3.6)
By using the positioner as a process controller, the previous position control function is a component of the main control loop.
The process controller within the main control loop posseses a PID function. The process setpoint (SP) is used and compared to
the controlled process value (PV). A sensor delivers the actual value. The manipulated variable correction functions as described
in figure 3.7 Z2 represents a disturbance variable.
SP
Process setpoint
Fig 3.7: Process control diagram
Top Control Positioner
Xd1
Position controller
Position control
Xd2
Process controller soleno-
id valve
B1
P
K
E1
Position Valve actuator
control soleno-
id valve
XPOS
Path measuring system
Valve
CMD Position
opening
control
loop
PV
Transmitter
Z1
Valve opening
Z2
Process value
Process
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