Determination of when a fluid in a container reaches a given level by use or a piezo-electric or electro-mechanical sensor that has increased power consumption when the fluid reaches the sensor, which is readily detected

摘要

A sensor (4) comprises excitation (5) and sensor (6) elements. Both are coupled to a control circuit (10), with the exciter generating mechanical vibrations that are transferred into the fluid when it reaches the sensor (1) so that the power consumption of the control circuit increases accordingly and an output signal (UA) measured using a detection circuit (R, 15) indicates the fluid level (3) has been reached.