Dayu Electronics: Why Does an Ultrasonic Level Meter Require Temperature Compensation?

Dayu Electronicsultrasonic level meter is a non-contact level measurement instrument controlled by a microprocessor. The ultrasonic waves of the level meter are emitted by the probe (sensor and transducer), and after being reflected by the surface of the object, they are received by the same probe and converted into electrical signals. The distance from the probe to the measured liquid surface is calculated based on the transmission time of the sound wave from emission to reception.

The ultrasonic level meter is based on the principle that the propagation speed C of ultrasound in a given medium is a constant. At atmospheric pressure and room temperature, the speed of ultrasound in air is approximately 340 m/s. However, in reality, for every 1°C increase in air temperature, the sound speed changes by about 0.6 m/s. Therefore, if the sound speed is still treated as a constant during calculation when the temperature rises, the measurement error of the liquid level will be significant.

To meet the accuracy requirements of industrial applications, the sound speed must be corrected, and the main method for sound speed correction is temperature compensation. Using temperature compensation in ultrasonic level meters helps improve the measurement accuracy of the system.