Level sensors ? the agony of choice?

If one is looking for a level sensor, one can be quickly overwhelmed by the large choice. An even sensor for limit level detection or continuous measurement could be ordered in a variety of technologies and design variants. But how do you find the appropriate level sensor for my application?
If one really wants to decide on a level sensor, the most important selection criterion may be the electrical output function. If one wants to monitor a limit in a tank, e.g. dry running (empty) or overfilled (full), then your level sensor should actually be a level switch. However, if it is vital that you 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 results in the exclusion of many technologies, if one wants 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 always the cheaper solution, if the application form 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 ? Painstaking , which permit 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 a variety of measurement technologies such as reed contact technology, optoelectronics, conductivity, vibronic and many more.
Each of these technologies has advantages and disadvantages, in addition to complex, application-specific limiting factors such as for example conductivity, dielectricity, density, contamination, colour, pressure strength, etc. A trusted statement concerning which technology is most suitable or may be used in a specific application environment can only be made after thorough assessment and frequently also your final test in the plant itself under real application parameters.
Note
WIKA offers you an extremely wide selection of level measuring instruments. More info on optoelectronic level switches, hydrostatic level sensors, float switches and additional instruments are available on the WIKA website. You will find videos on the functionality of the average person measuring principles on our YouTube channel. Your contact person will undoubtedly be pleased to help you on selecting the most appropriate product solution.

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