Ultrasonic Level Measurement

Ultrasonic Level Measurement

Ultrasonic level measurement is a time-of-flight, non-contact method used for continuous level measurement in liquids and many bulk solids applications. It is positioned as maintenance-free and cost-effective for a wide range of services, including fluids, pastes, sludges, and powdery to coarse bulk materials. The method is also described as unaffected by dielectric constant, density, or humidity, and as resistant to build-up effects due to the self-cleaning behavior of the sensor diaphragm.

The measuring principle is straightforward: the sensor emits ultrasonic pulses toward the material surface, the surface reflects the signal, and the sensor receives the echo. The instrument measures time-of-flight, which is proportional to distance traveled, and uses known tank geometry to calculate level. This is the same fundamental ranging concept used in many distance-measurement technologies, adapted for industrial process environments with suitable signal processing and installation options.

Benefits include non-contact measurement that reduces exposure to corrosion, coating, and mechanical wear. The category is characterized by easy planning and assembly, fast and safe commissioning, long service life, and reduced maintenance cost. Additional advantages listed include calibration without filling or discharging and a self-cleaning effect due to the vibrating sensor diaphragm, which can improve stability in services prone to light buildup.

Typical applications include level measurement in abrasive and aggressive media, often in rough ambient conditions, along with common utility and process services such as wastewater basins, chemical sumps, and storage vessels. In bulk solids, ultrasonic is used where the surface can be ranged reliably within the application’s distance and dust constraints. Compact and remote electronics configurations support deployment across varied mounting limitations and panel/field architecture preferences.

Application success depends on managing acoustic path conditions: heavy vapors, temperature gradients, and turbulent surfaces can affect echo quality and should be considered during selection and mounting. Nozzle length, sensor aiming, and avoidance of internal obstructions help reduce false echoes. Configuration should align with vessel geometry and define signal damping, blanking zones, and alarm setpoints appropriate to process dynamics so that the measurement remains stable through normal fill/empty transients.

At Eastern Controls, We are proud to be the exclusive authorized sales and service representative for Endress+Hauser.