Level measurement in liquids and bulk solids

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Level measurement

Point level detection in liquids

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Point level detection in liquids Choose the measuring principle which fits best for your application.

Float switch As the switch floats up and down on the surface of a liquid, an installed sensor detects its position and triggers the switching operation.

Vibronic A sensor in form of a tuning fork is excited at its resonant frequency. The drive works piezoelectrically. The oscillating frequency changes as the fork enters the medium. The change is analyzed and translated into a switching signal.

Advantages • Unaffected by media • Ready for use without calibration • Self-monitoring • Can be used in turbulent and effervesce liquids

Advantages • Favourable measuring principle • Also for Ex area applications

Capacitance

Radiometry The radiometric measuring principle is based on the fact that gamma radiation is attenuated when it penetrates a medium. The radiation source is installed in a source container, which allows the radiation to be emitted only in the direction of the process vessel. The detector is positioned on the opposite side of the process vessel. It converts the received radiation into an electrical signal and uses it to calculate the level.

A capacitance probe may be compared to an electric capacitor. As the tank is filled, the probe capacity increases. This change is electrically analyzed.

Advantages • Tried and tested in operation, robust and safe • Simple commissioning • Versatile • Reliable function independent of build-up

Advantages • Non-contact measurement from outside • Made for extreme measuring tasks where other principles can not be used

Conductive The resistance between two measuring electrodes changes by the presence or absence of a medium. In single-rod probes, the electrically conductive tank wall serves as a counter electrode.

Advantages • Multipoint detection with one process connection • Simple instrumentation