Differences between contactless and contact radar level gauges

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Principle of contact radar level gauge: Based on the Time-Domain Reflection principle, the electromagnetic pulses emitted by the radar level gauge travel at the speed of light along a rod-shaped or cable-type antenna. When these pulses encounter the surface of the medium being measured, some of them are reflected to form echoes that return along the same path to the pulse transmitter. The distance between the transmitter and the surface of the medium is proportional to the time it takes for the pulses to travel between them; by calculating this value, the liquid level can be determined. In some specific operating conditions, guided wave radar exhibits clear advantages. For example, in situations where there is stirring inside a tank or significant fluctuations in the medium, measurements taken using a guided wave radar fixed at the bottom are more stable compared to those from conventional radars. When measuring the level of liquid in small tanks, where there is limited space for installation or many interfering elements inside the tank, conventional radars are generally not suitable; in such cases, the advantages of guided wave radar become evident. Another scenario involves conditions with a low dielectric constant – both conventional radars and guided wave radars rely on differences in the dielectric constant of the medium to function. Since the waves emitted by conventional radars spread out, when the dielectric constant is too low, the signal becomes too weak, resulting in unstable measurements. In contrast, the waves from guided wave radars propagate along the guide rods, ensuring relatively stable signals. Additionally, most guided wave radars have a bottom detection function that allows for corrections based on the echo signals from the bottom, thereby enhancing the stability and accuracy of the measurements. Applications: Used in liquid storage tanks, acid and alkali storage tanks, slurry storage tanks, solid particles, and small oil storage tanks. Such as: coal bins, ash bins, oil tanks, acid tanks, etc. Principle of non-contact radar level gauge: High-frequency wave pulses are transmitted and received via an antenna system; the radar waves travel at the speed of light, and the travel time can be converted into a level signal using electronic components. Advantages: Continuous level measurement for liquids, particles, and slurries. The measurement of radar level gauges is not affected by the medium, temperature, inert gases, steam, dust, foam, etc., making them suitable for use in explosive hazard areas. Application: It does not come into direct contact with the medium, making installation convenient. When measuring the amount of solid material, there is no need to consider the impact of the material on the antenna. It can meet the requirements of complex operating conditions. For example: special environments such as high dust levels, foam, condensation, crystallization, etc. Xi’an Dinghua Electronics Co., Ltd., established in 1992 and currently located in Xi’an, Shaanxi Province, is a high-tech enterprise that specializes in the research and development, production, sales, and engineering services of radar level measurement instruments. At present, the company offers a range of products including radar level gauges, external liquid level meters, fork-type level switches, electro-hydraulic actuators, ultrasonic flowmeters, and external thermometers. All of these products have withstood numerous complex operating conditions in actual field applications, and are widely used in industries such as petroleum, chemicals, power generation, coal, metallurgy, as well as food and pharmaceuticals. Professional selection guidance, excellent product quality, reasonable prices, fast delivery times, and comprehensive pre-sales, in-sales, and after-sales services…