Liquid Sensors

AST's liquid sensors often combine several measurement principles in one sensor. For example, the fill level measurement is often combined with a liquid concentration/quality measurement. For fill level measurement, the technologies used range from ultrasound to capacitive systems and hydrostatic pressure measurement. The most suitable measuring principle is selected based on customer requirements and the respective available installation space.

In addition to ultrasonic systems, thermal conductivity measurements are often used to determine concentration and quality. Sensors based on the tuning fork principle not only enable high-precision density measurement, but also measure the viscosity of the respective medium. Our liquids product portfolio is rounded off with measuring instruments based on the resistive and capacitive measuring principle. Concentration measurement is used, for example, in determining the ethanol concentration in cleaning fluids in the windshield wiper tank and exhaust gas treatment with AdBlue® (measurement of the urea concentration).

All AST sensors are equipped with a microcontroller and can calculate complex algorithms directly at the sensor. An output signal processed in this way is made available in analog or digital form.