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Recently, people have been asking what the differences are between radar level gauges and guided wave radar level gauges. A detailed introduction is now provided. I. Principle of Radar Level Gauges The basic working principle of radar level gauges is transmission–reflection–reception: the antenna of the radar sensor emits electromagnetic wave signals in the form of beams; these emitted waves are reflected by the surface of the material being measured, and the reflected echo signals are then received by the antenna. Each point in the transmitted and reflected beams is acquired using ultrasonic sampling. After being processed by the intelligent processor, the signal determines the distance between the medium and the probe, which is then sent to the terminal display for display, alarm generation, operation, etc. https://p3-sign.toutiaoimg.com/tos-cn-i-qvj2lq49k0/a664ed019d7d41ac985fefc2d283d52e~noop.image?_iz=58558&from=article.pc_detail&x-expires=1674538936&x-signature=NO62RgvIQU8ba9s5wosC8%2FDikS8%3D The biggest advantage of radar level gauges is their excellent performance under harsh conditions. It can measure both toxic and corrosive media, as well as solid, liquid, powdered, or slurry-form media. In terms of measurement, it has the following features: 1. Continuous and accurate measurement: The probe of the radar level gauge does not come into contact with the surface of the medium, enabling non-contact measurement that allows for accurate and rapid detection of different types of media. The probe is hardly affected by temperature, pressure, gases, etc. (the impact is only 0.018% at 500°C and 0.8% at 50 bar). 2. It has a function to suppress interference echoes. 3. Accurate, safe, and energy-saving: Radar level gauges use materials with high chemical and mechanical stability, and these materials can be recycled, making them highly environmentally friendly. 4. No maintenance required and highly reliable. Microwaves are hardly disturbed, do not come into direct contact with the medium being measured, and can be applied in a wide range of situations, such as vacuum measurement, level measurement, or inventory level detection. Thanks to the use of advanced materials, it is resistant to highly complex chemical and physical conditions, and it can provide accurate, reliable, and long-term stable analog or digital level signals. 5. Easy to maintain and simple to operate. 6. The radar level gauge has fault alarm and self-diagnosis functions. Faults are analyzed based on the error codes indicated by the operation display module; the faults are identified promptly and resolved, thereby making maintenance and correction more convenient and accurate and ensuring the proper operation of the instruments. 7. Wide range of applications – can measure almost all types of media ； In terms of the shape of the tank, radar level gauges can measure the liquid level in spherical tanks, horizontal tanks, cylindrical tanks, and conical cylinders ； In terms of tank functions, it is possible to measure the liquid level in storage tanks, buffer tanks, microwave tubes, and bypass pipes ； In terms of the medium to be measured, liquids, particles, slurries, etc., can be measured. In general, radar level gauges have a wide range of applications and employ a non-contact measurement method. It features high-quality materials and a low failure rate. Second, the principle of the guided wave radar level gauge: The guided wave radar level gauge is a measuring instrument based on the time-of-travel principle. 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-like probe; when these pulses encounter the surface of the material, they are reflected back and captured by a receiver within the instrument, which then converts the distance signal into a level signal. https://p3-sign.toutiaoimg.com/tos-cn-i-qvj2lq49k0/9c7679910b234eb5965fd72e84d4e17d~noop.image?_iz=58558&from=article.pc_detail&x-expires=1674538936&x-signature=BKOXmLS8D5R1%2FnzitvwL0IbjZe8%3D Feature 1: It has a strong ability to suppress steam and foam, ensuring that measurements are not affected ； 2. Unaffected by liquid density, the looseness of solid materials, temperature, and dust during feeding ； 3. Low maintenance, high performance, high precision, high reliability, and long service life. III. Differences between radar level gauges and guided wave radar level gauges. Difference 1: Different contact methods. Radar level gauges are non-contact, while guided wave level gauges are contact-type. In other words, waveguide types cannot be used in applications with high requirements for food grade. Difference 2: The working medium differs. Guided wave radar level gauges require more consideration to be given to the corrosiveness and stickiness of the medium, and installing and maintaining such gauges when they are too long is more difficult. In conditions of low dielectric constant, both radar and guided wave radar rely on the difference in the dielectric constant of the medium for their measurement principles. Since the waves emitted by conventional radar are divergent, when the dielectric constant of the medium is too low, the signal becomes too weak, resulting in unstable measurements. In contrast, the waves from guided wave radar propagate along the guided wave rod, ensuring relatively stable signals. Additionally, most guided wave radars have a bottom detection function that allows for corrections based on the signals reflected from the bottom, thereby enhancing the stability and accuracy of the signals. Difference 3: The selection process is different. Ordinary radars can be used interchangeably, whereas guided wave radars cannot be interchanged since the length of the guided wave rod (cable) is fixed based on the original operating conditions. As a result, selecting a guided wave radar is more complicated than selecting an ordinary radar. Difference 4: Different measurement ranges. Ordinary radars are commonly used on tanks with a diameter of 30 or 40 meters, and can even measure up to 60 meters. Guided wave radar also needs to take into account the stress on the guided wave rod (cable); due to this stress, the measurement range of guided wave radar is generally not very long. However, in some specific operating conditions, guided wave radar has clear advantages; for instance, when there is stirring inside the tank or significant fluctuations in the medium, the measurement values obtained using a guided wave radar fixed at the bottom are more stable than those from a movable radar ； There is also level measurement in small tanks; due to the limited space available for installation or the presence of many obstacles inside the tank, conventional radars are generally not suitable, and this is where the advantages of guided wave radars become apparent. Difference 5: Different styles – Radar level gauges have a trumpet-shaped design, while guided wave level gauges feature a guided wave rod. Since the two shapes are different, they will naturally perform differently in some applications.