XKCON-water level sensor is a sensor developed by using the characteristics of ultrasonic waves. Ultrasound is a vibration frequency higher than the sound waves of mechanical waves, generated by the vibration of the transducer chip under the excitation of voltage, it has a high frequency, short wavelength, small bypass phenomenon, especially good directionality, can become a ray and directional propagation and other characteristics. Ultrasound on the liquid, solid penetration ability is very large, especially in the sun opaque solid, it can penetrate the depth of tens of meters. Ultrasound encounters impurities or interfaces will produce significant reflection of the formation of reflections into echoes, encounter active objects can produce the Doppler effect. Therefore, ultrasonic testing is widely used in industry, national defense, biomedicine and other aspects of ultrasound as a means of detection, must generate ultrasound and receive ultrasound. The device to complete this function is the ultrasonic transducer, customarily called ultrasonic transducer, or ultrasonic probe.