For density measurement the liquid flows through a thin U-shaped tube inside the sensor. Using electromagnets, the tube is excited to oscillate at the resonant frequency. At the same time, an integrated reference oscillator measures the oscillation characteristics. Even the smallest changes in fluid density have an impact on the detected signal and are identified with highest precision. 

For sound velocity measurement a sound pulse is created by a piezo-element in a sonic transmitter. It moves perpendicular to the product flow towards a sonic receiver where it is detected. Since the distance between transmitter and receiver is known, the sound velocity can easily be calculated by measuring the travel time of the sonic signal.