Principle of operation of Ultrasonic Level Devices

Ultrasonic transducer matched to air is stimulated by a pulse transmitter and it generates a pressure wave that propagates to a target and then reflects.

Reflected wave is received by the same transducer in the receiver mode and converted to an electrical signal (similar to a microphone).

Ultrasonic Level Devices

The electrical signal is amplified and processed to find the reflected echo and then calculated to find the distance to a specific target.

Distances to a target are converted linearly to 4mA to 20mA current and optionally information about level measurement is sent via RS232 or RS 485 to a PC for processing such as diagnostics, programmable set-up and data logging.