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Typ EP 501
Description of System
8.
POSITIONER TYPE EP 501
The position sensor records the current position (
POS
) of the pneumatic actuator. The positioner compares this
actual position value with the set-point value (
CMD
) which is specified as a standard signal. If there is a control dif-
ference (Xd1), the actuator is aerated and deaerated via the control system. In this way the position of the actuator
is changed until control difference is 0. Z1 represents a disturbance variable.
Valve opening
Continuous
valve
Control system
Solenoid valves
Position sensor
Positioner
Position set-
point value
CMD
Xd1
B1
E1
P
K
Z1
POS
Position control circuit
+
-
Figure 3:
Position control circuit in Type EP 501
english