Level sensors ? the agony of preference?

If one is searching for a level sensor, one can be quickly overwhelmed by the huge selection. A level sensor for limit level detection or continuous measurement can be ordered in a number of technologies and design variants. But how do you find the appropriate level sensor for my application?
If one really wants to select a level sensor, the main selection criterion is the electrical output function. If Emerging wants to monitor a limit in a tank, e.g. dry running (empty) or overfilled (full), then your level sensor should actually be considered a level switch. However, if it is important to monitor the contents of a tank at length (e.g. 0 ? 100 % fill level), the other needs continuous measurement (= level sensor).
The distinction between level sensor and level switch automatically leads to the exclusion of several technologies, if one is looking for probably the most economical solution. Although a level sensor with combined electronics can communicate both an analogue signal and switching signals, a pure level switch is definitely the cheaper solution, if the application is limit level measurement only.
The selection of the best option measurement technology
Continuous measurement with float
Level sensors typically feature continuous analogue output signals, such as 4 ? 20 mA or 0 ? 10 V, which let the accurate measurement of level and its variation. The sensors could be based on various measurement technologies such as for example magnetostriction, reed-chain technology, hydrostatic, ultrasound, radar and many more ? the choice which varies from manufacturer to manufacturer.
Point measurement with optoelectronic level switch
Level switches in a traditional float switch design provide a mechanical switch contact or, in electronic version, generally a PNP or NPN transistor output. In neuro-scientific switches, additionally, there are many different measurement technologies such as for example reed contact technology, optoelectronics, conductivity, vibronic and much more.
Uninterested of these technologies has benefits and drawbacks, together with complex, application-specific limiting factors such as conductivity, dielectricity, density, contamination, colour, pressure strength, etc. A trusted statement as to which technology is the most suitable or can be used in a particular application environment can only be made after thorough assessment and frequently also a final test in the plant itself under real application parameters.
Note
WIKA offers you an extremely wide selection of level measuring instruments. Further information on optoelectronic level switches, hydrostatic level sensors, float switches and further instruments are available on the WIKA website. You can find videos on the functionality of the average person measuring principles on our YouTube channel. Your contact person will be pleased to advise you on selecting the most appropriate product solution.

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