Operation Manual

Continuous valve actuator CHEOPS control
theben
As of: Jul-11 (Subject to change without notice) Page 41 of 71
Diagram 1 shows a characteristic valve curve, as occurs frequently in practice.
In this characteristic curve, a 30% flow occurs at a valve stroke as low as 10%. At a valve
stroke of 50%, the flow is over 80%.
Diagram 1
Example of a characteristic curve
0%
20%
40%
60%
80%
100%
0% 20% 40% 60% 80% 100%
Valve position
Volumetric flow
A linear characteristic curve as shown in Diagram 2 would be ideal for the control.
A non-linear characteristic curve can be linearised by inputting an own characteristic curve.
To do this, the valve position (stroke) at 10, 20.....90% is taken from Diagram 1 and "internal
characteristic curve" entered into the parameter page.
Diagram 2
Linear characteristic curve
0%
10%
20%
30%
40%
50%
60%
70%
80%
90%
100%
0% 20% 40% 60% 80% 100%
Valve position
Volumetric flow