ultrasonic level sensor working principle

An ultrasonic level transmitter is a microprocessor-controlled digital level meter. In measurement, ultrasonic pulses produced by a emitting sensor (transducer) are reflected by the fluid receiving the same sensor or an ultrasonic receiver, resulting in a surface acoustic wave which is then converted into an electrical signal by a piezoelectric crystal or a magnetostrictive device. This is done by transmitting and receiving sound waves to calculate the time between the sensor surface and the measured distance.