Sensors for level measurement

Sensors for level measurement are used to determine the filling level, for example the water level of a vessel. They are used to detect whether a desired level has been reached. We distinguish here between optical and capacitive sensors for level measurement.

Optical level sensors

Optical level sensors measure the level with a so-called light emitter, from which a light is emitted (i.e. radiated). The liquid inside the vessel reflects this light. The intensity of the reflected light is detected by a photodetector and thus the level is measured.

Capacitive level sensors

Capacitive level sensors measure the level by direct liquid contact. This makes use of the electrical conductivity of the liquid. When the contacts of the capacitive sensors (the so-called electrodes) are connected to each other by a conductive element, such as water, the capacitance of the electrodes also changes. If the liquid level rises, the contacts of the sensor are increasingly covered - the capacitance increases.