Level measurement in liquids and bulk solids

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Level measurement

Point level detection in bulk solids

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

Vibronic A one-rod sensor or a tuning fork is excited at its resonant frequency. The drive works piezoelectrically. The amplitude changes as the fork enters the medium. The change is analyzed and translated into a switching signal.

Microwave barrier

Microwave barrier: Detection of all kinds of bulk solids is based on microwaves (transmitter-receiver principle). Bulk solids movement sensor: Detection of bulk solids movement (present / not present) is based on microwaves (Doppler effect). Inspection glasses have to be installed in case of metallic container walls. Installation in contact with the process is also possible. 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.

Advantages • Universal point level switch • Largest variety of certificates, housings, electronic inserts, process connections and sensor geometries • Easy installation • No wear and tear / maintenance-free

Advantages • Non-invasive in tanks penetrated by microwaves from outside • Direct assembly with threaded connection • May also be used as a counter for individual items

• Measuring principle almost unaffected by process conditions (e.g. pressure, temperature, aggressive and abrasive media, dust, contamination build-up)

Capacitance 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 • Easy commissioning • Versatile

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

Paddle

The rotation of the paddle is stopped as it is covered by solids. This actuates a relay.

Advantages • Measuring principle for simple applications • Calibration not required • Rotation monitoring