Type 8694
Systemdescription
5.4.3
Function diagram of the positioner with single-acting
actuator
The illustrated function diagram describes the function of the positioner (Type 8694).
external
position
set-point value
Positioner
Pneumatic actuator
(single-acting)
Figure 3:
Function diagram
Position
controller
Actual
position
Control system
Position
measuring
system
Valve
(actuator)
Control system
1: Aeration valve
2: Bleed valve
1
Pressure
supply
2
Exhaust air
english
15