SOPA-...
Festo – SOPA-... – 2017-09b English
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2
Function and application
The air gap sensor SOPA-... is intended for distance monitoring in a range of 20...200 μm. The distance
measurement is performed using a non-contact pneumatic measuring process. This enables it to be
used in harsh ambient conditions.
2.1
Design
The system consists of two sub-components. The control module provides acompressed air
preparation that is adapted to the supply pressure of the sensor module, as well as the functionality for
switching measuring and exhaust air. Up to 4 sensor modules contain the sensory functions. The sensor
modules can be operated both individually and in combination with the control module.
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aJ
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3/2-way valve (instrument air)
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Pressure regulator
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3/2-way valve (exhaust air)
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Supply pressure
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Sensor modules (pneumaticallylinked)
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Object (example)
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Measuring nozzles
(1 per sensor module)
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Air gap
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Vent screw
aJ
Supply port for operating pressure
Fig. 3
Configuration – with a control module and two sensor modules here
The compressed air flows from the sensor modules to the measuring nozzles. If the object is very close
to a measuring nozzle, the air gap is very small and only a small amount of air flows through. As the
object gets further away, the air gap becomes larger and more air flows through. The change in flow
rate is detected by the sensor modules, converted into a distance-correlated value and displayed
(speed measuring method with ejector).