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An ultrasonic level gauge operates on the principle of transmitting and receiving ultrasonic waves. The speed at which ultrasonic waves travel through air is constant; these waves are sent out and then the waves reflected back from the liquid surface or an object’s surface are detected. By timing the period from the emission of the waves to the reception of the echoes, it is possible to determine the time it takes for the ultrasonic waves to travel through the air. Since it is a round trip, the actual distance is half of the total distance. The depth of the tank or the height of the container remains constant; therefore, the actual liquid level is equal to the depth of the tank minus the distance measured by the ultrasonic level gauge, which represents the height of the liquid level or the level of the substance. Thus, ultrasonic measurement of liquid level or object level is achieved. As ultrasonic level gauges become increasingly widely used in modern industry, their application areas are expanding as well. However, there are two situations in which ultrasonic level sensors are not very suitable for use. These include: 1. In environments with stirring, ultrasonic level gauges generate erroneous signal echoes when measuring the liquid level, as the level keeps changing during stirring, resulting in significant variations in the data read by the sensor and leading to measurement results that do not meet the customer’s requirements. 2. Ultrasonic level gauges are used to measure acidic and alkaline liquids with high concentrations; in such cases, there may be a problem where no echo signal is detected by the gauge. In fact, there is nothing wrong with the ultrasonic technology itself, but it is the high-concentration acidic and alkaline liquids that generate dense gas mist which absorbs the ultrasonic waves, resulting in no echo being detected and thus causing the ultrasonic level gauge to fail to function properly. The echo intensity of ultrasonic waves is primarily influenced by two factors: firstly, the more stable the propagation medium, the better it is for the waves to propagate; secondly, the smoother the surface of the medium being measured, the greater its acoustic impedance (the harder it is), which facilitates the reflection of echoes. Specifically: 1. The more stable the propagation medium, the better it is for propagation: Ultrasonic waves are mechanical waves. Mechanical waves are affected by the stability of the medium through which they propagate. For example: there is a pond with water. When the wind is calm, throwing a stone into the pond creates ripples on the water’s surface; but when strong winds cause waves in the pond, it becomes difficult to see ripples even when a large stone is thrown in. There are many factors that can cause air fluctuations; for example, dust, air currents, steam, and material flows can all lead to air fluctuations, reducing the quality of the echoes and affecting the accuracy of measurements. When phenomena such as dust and air currents are severe, it is recommended to use a low-frequency ultrasonic level gauge for measurement. 2. The smoother the surface of the medium being tested, the higher its acoustic impedance (the harder it is), which facilitates the reflection of echoes. During solid measurements, the surfaces being measured are uneven and have a certain angle of repose. The reflected wave under these conditions is a diffuse reflection wave. Since the reflection in ultrasonic level gauges is related to the wavelength, reflection can occur only when the dimensions of the reflecting surface are comparable to or larger than the wavelength. Obviously, the higher the operating frequency, the shorter the wavelength, and for smaller materials, diffuse reflection is more likely to occur. For example, the wavelength of a mechanical wave with a frequency of 10 KHz in air is 34 mm; in most cases, the dimensions of materials are not that large. Furthermore, when operating at low frequencies, the emission beam has a large opening angle, resulting in a wide echo. The data measured at this time is therefore inaccurate, sometimes differing by several hundred millimeters or even 1 meter or more. Therefore, for measuring the level of solids with small particles, it is recommended to use a high-frequency ultrasonic level gauge. For more information, please visit the company’s official website at http://www.yb1518.com/. Please retain this link when reproducing the content! http://www.yb1518.com/UploadFiles/2011118121525564.jpg