Motorised control valve
Flow control
Motorised control valve
Aside from valves equipped with a lifting solenoid, motor-actuated control valves can
also be used for many applications in proportional technology.
They are particularly suitable for controlling the volume flow rate of liquid fluids.
The flat rotary slide disc design of ASCO’s motorised control valves works similar to that of a single-lever water
tap known from sanitary applications. But, instead of the manual lever, a motor is used to provide continuous
adjustment of the volume flow between the “fully closed” and the “fully open” positions (0-100%). The
throttling element itself consists of two ceramic discs which are adjusted in opposite rotation to each other over
an axis and an electric motor with drive. A generally triangular-shaped aperture is maintained over the angle of
rotation during regulation, providing a virtually linear flow characteristic. The ceramic discs, which are wearresistant and insensitive to contamination, have proven themselves a million times over in sanitary and kitchen
fittings.
A low-power electric DC motor is used so the valve is directly controlled from the electronics. A built-in rotary
potentiometer detects the feedback. The motorised valve is equipped with an internal PID controller to control
the valve‘s position which is held on loss of power (fail-safe behaviour).
Motor with drive,
potentiometer and electronics
Drive shaft
Flat rotary slide disc
Valve body
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P R I N C I P L E
Closed
Setpoint 0V (0/4mA),
flat rotary disc apertures fully
obstructed: no flow
Half open
Setpoint e.g. 5 V (10mA),
flat rotary discs rotated by 45°
relative to each other:
half flow
Open
Setpoint e.g. 10V (20 mA),
flat rotary discs rotated by 90°:
maximum flow
T E C H N I C A L
Fluids:
Air, gases, liquids
Pressure range:
Vacuum to 10 bar
Ports:
C H A R A C T E R I S T I C S
Advantages:
■
Wear-resistant flat rotary slide valve made
of oxyde ceramics
G 1/2
■
No waterhammer
Flow:
Kv 1,1 (m3/h)
■
Construction:
Flat rotary slide valve
Suitable for flow control in combination
with a stand-Alone PID ControlD controlling
device
Actuation:
DC motor
■
No minimum operating pressure required
Setpoint:
0-10 V, 0-20mA, 4-20mA
■
Low power consumption
Feedback:
0-10 V
■
Insensitive to contamination
■
Mechanical separation of electrical actuator from fluid-carrying parts
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Motorised control valve
O P E R A T I N G
More information on motorised
control valve
Page 97
More information on
C ontrol D
Page 99