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A radar level gauge is a highly reliable, contactless measuring instrument. It is precisely the characteristic of non-contact measurement that allows the instrument to remain in no direct contact with the medium being measured, thereby avoiding to some extent the problems of inaccurate readings or even the inability to conduct measurements that occur with most plug-in instruments due to contamination or corrosion of their sensing elements. Nevertheless, due to the complex and precise structure of radar level gauges, improper operation or lack of maintenance during use can lead to frequent malfunctions of the instrument, affecting accurate measurements. So, what are the common problems with radar level gauges? What other solutions are there? Generally speaking, the common problems that arise in the operation of radar level gauges include the following three situations: First, scaling on the antenna of the radar level gauge. Common issue: Usually, deposits with a low dielectric constant have little impact on the measurement accuracy of the instrument when it is in a dry state; however, deposits with a high dielectric constant often lead to inaccurate measurement results. Solution: To address this issue, it is recommended to use compressed air to blow or clean with water in order to remove the deposits. If the scarring is persistent, an acidic cleaning solution should be used to remove the alkaline deposits; however, measurements of the material level must be stopped during the cleaning process. II. The antenna of the radar level gauge gets submerged. Common issue: The antenna of the radar level gauge is prone to being submerged by the material, which affects the measurement accuracy and can cause damage to the probe. Solution: It is recommended to switch from a radar level gauge to a guided wave tube measurement method; this can improve the measurement conditions and enhance the performance of the gauge. The specific approach is to install a guided-wave radar level gauge at the original opening; the guided wave tube is positioned about 0.2 meters above the steam exhaust pipe. In this way, even in adverse conditions where slurry overflows from the steam exhaust pipe, the antenna of the level gauge is not submerged by the slurry. It also prevents interference from the vortices generated by the mixer as well as excessive steam escaping from the probe, thereby reducing damage to the probe. Additionally, thanks to the excellent focusing effect of the guided wave tube, the radar wave signals received are stronger, resulting in high-quality measurement results. III. Scaling and scarring on the probe of radar level gauges Common problem: When scaling or scarring occurs on the probe of a radar level gauge, the electromagnetic wave signals transmitted by the gauge are blocked, which can lead to malfunctions in the gauge. Solution: This issue can be avoided by raising the installation height of the probe. If an increase cannot be achieved due to installation constraints, the issue should be resolved by interlocking the material level measurement with the pump of that tank; specifically, the maximum material level setting should be reduced by about 0.5m, so that when the material level reaches this maximum value, the feed pump can be stopped or the discharge pump can be started. In addition to the failure of radar level gauges caused by the obstruction of the aforementioned electromagnetic wave signals, the state of the medium can also affect the proper functioning of these gauges. For example, if there is foam on the surface of the material being measured under actual operating conditions, whether it is dry foam or wet foam, radar waves can still be reflected normally. However, when the foam is too thick and viscous, it may lead to significant measurement errors or even make measurement impossible. Under such operating conditions, radar level gauges do not have any advantage in terms of measurement, and it is recommended to replace them with other measuring instruments. Therefore, in general, if the measurement data from a radar level gauge is inaccurate, it can be assumed that the cause of the problem is that the electromagnetic wave signal has been blocked due to some factor, and thus has not reached the actual surface of the liquid level. Instrumentation staff are responsible for promptly addressing the common faults of radar level gauges, and they are even more obliged to carry out proper maintenance of these instruments on a regular basis to ensure their proper and safe operation. 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 measurement level instruments, fork-type level switches, electro-hydraulic actuators, ultrasonic flow meters, and external temperature sensors. All of these products have withstood numerous complex operational conditions in real-world settings, and they are widely used in industries such as petroleum, chemicals, power generation, coal mining, 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…