Factors Affecting Accurate Measurement of Radar Level Meters

　　At present, radar level meter is widely used in the liquid level measurement industry. It mainly adopts non-contact measurement, and the measured medium is almost unrestricted, becoming the leader among many liquid level measurement instruments. It not only solves the leakage and maintenance defects caused by contact medium measurement, but also can meet the measurement needs of most closed or open containers.

　　Although radar level meters have obvious advantages in practical applications, there are still many factors that will affect the measurement of the product and cause errors. Radar level meters are mainly affected by the following three factors:

　　1. Temperature: Radar is a mechanical wave. Changes in temperature will affect changes in the speed of sound. In actual measurements, a variety of natural factors can cause errors. Advanced measurement systems, including temperature sensors and software functions, can automatically compensate for the effects of temperature. In actual applications, due to the environment around the probe, the temperature of the radar propagation medium and the temperature of the measured medium are different. The measurement system should select a built-in temperature sensor combined with the probe and an external temperature sensor separated from the probe according to actual requirements. A more accurate measurement system can place an echo reflection reference at a specific distance from the probe to generate a reference echo to compensate for the temperature effect. The effectiveness of this method depends on the accuracy of the placement of the echo reflection reference.

　　2. Dust: Dust is one of the most influential factors in radar measurement. The dusty environment has a very small effect on the speed of sound, but the attenuation of the radar is very obvious, which is the main factor hindering the implementation of radar solutions. In practical applications, the use of low-frequency probes with special plastic surfaces in dusty environments is very successful.

　　3. Working pressure: Pressure mainly affects the probe. There is also a certain relationship between pressure and temperature. Therefore, changes in pressure affect changes in temperature, which in turn affects changes in sound speed.