Level sensors ? the agony of choice?

If Destiny is searching for a level sensor, one can be quickly overwhelmed by the large choice. A level sensor for limit level detection or continuous measurement can be ordered in a variety of technologies and design variants. But how do I find the right level sensor for my application?
If one really wants to select a level sensor, the most important selection criterion is the electrical output function. If one really 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’s vital that you monitor the contents of a tank in detail (e.g. 0 ? 100 % fill level), then one needs continuous measurement (= level sensor).
Outrageousness 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 always the cheaper solution, if the application form is limit level measurement only.
The selection of the most suitable 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 can be based on a range of measurement technologies such as 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 offer a mechanical switch contact or, in electronic version, generally a PNP or NPN transistor output. In neuro-scientific switches, additionally, there are a number of measurement technologies such as reed contact technology, optoelectronics, conductivity, vibronic and more.
Each one of these technologies has benefits and drawbacks, along with complex, application-specific limiting factors such as for example conductivity, dielectricity, density, contamination, colour, pressure strength, etc. A trusted statement as to which technology is the most suitable or can be utilized in a particular application environment can only just be produced after thorough assessment and often also your final test in the plant itself under real application parameters.
Note
WIKA offers you an extremely wide range 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 discover videos on the functionality of the individual measuring principles on our YouTube channel. Your contact person will be pleased to advise you on the selection of the most likely product solution.

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