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I. Product Overview: Level is an important parameter in industrial production. There are many methods for level measurement. Depending on the operating conditions and the type of medium, level gauges based on different measurement principles can be used. Commonly used level measurement instruments such as the blowing method, hydrostatic method, float-type method, weight-type method, and ultrasonic method all have their own characteristics and application ranges. Guided wave radar level gauges utilize advanced radar measurement technology, and thanks to their excellent performance – especially under harsh measuring conditions such as agitation in tanks, high temperatures, high levels of steam, highly corrosive media, and tendency to form scale – they exhibit outstanding capabilities and are playing an increasingly important role in industrial production. II. Technical Performance: Radar waves are a special form of electromagnetic wave, and guided-wave radar level gauges utilize the unique properties of these electromagnetic waves to detect liquid levels. The physical properties of electromagnetic waves are similar to those of visible light, and their propagation speed is equivalent to the speed of light. Its frequency ranges from 300 MHz to 3000 GHz. Electromagnetic waves can penetrate interference sources such as space vapor and dust; they are easily reflected when encountering obstacles. The better the conductivity or dielectric constant of the medium being measured, the stronger the reflection of the echo signal. The higher the frequency of the radar waves, the smaller the transmission angle, the greater the energy (flux or field strength) per unit area, and the less attenuation of the waves – all of which lead to better measurement performance in guided-wave radar level gauges. III. Working Principle: A guided-wave radar level gauge mainly consists of a transmitting and receiving unit, a signal processor, an antenna, an operation panel, a display, and fault alarm functions. Transmission-reflection-reception is the basic principle behind the operation of guided-wave radar level gauges. The antenna of the radar sensor emits radar signals with a frequency of at least 5.8 GHz in the form of beams. The reflected signal is still received by the antenna, and the time it takes for the radar pulse to travel from transmission to reception is proportional to the distance from the sensor to the surface of the medium as well as to the level of the object. A guided wave radar level gauge is a type of radar level gauge that operates on the principle of time-domain reflection (TDR). The electromagnetic pulses emitted by this gauge travel at the speed of light along a steel cable or probe; when they encounter the surface of the medium being measured, some of these pulses are reflected, forming echoes that return along the same path to the pulse transmitter. When the pulses reflect off the surface of the material, they are captured by a receiver within the gauge, which converts the distance information into a level signal. The distance between the transmitter and the surface of the medium being measured is proportional to the time it takes for the pulses to travel between them, and the liquid level can be determined through calculations. Operating time can be converted into a level signal through electronic components. Furthermore, guided-wave radar can also measure the interface between two different media, making full use of the principle of different dielectric constants in these media. Radar waves travel at the speed of light, and the travel time can be converted into a level signal using electronic components. The probe emits high-frequency pulses that travel along the cable; when these pulses encounter the surface of the material, they are reflected back and captured by a receiver inside the instrument, which then converts the distance signal into a level signal. The reflected pulse signal is transmitted along the cable to the instrument’s electronic circuitry, where the microprocessor processes this signal to identify the echoes generated by the microwave pulses on the surface of the material. The correct identification of echo signals is carried out by intelligent software. The distance D from the surface of the material is proportional to the time duration T of the pulse: D = C×T/2, where C is the speed of light. Given the distance E of the empty tank, the level L can be calculated as follows: L = E – D. The output is determined based on the input values of the height of the empty tank E (equal to zero) and the height of the full tank F (equal to the full scale), as well as some application parameters. These parameters enable the instrument to adapt itself to the measurement environment. Corresponds to a 4-20mA output.