In order to make reading more simple and convenient, we analyze how to select radar level meter for liquid level measurement and solid material level measurement respectively in the following chapters. The first part focuses on the analysis of liquid level, so this paper will analyze it from the perspective of solid level. The solid level has the phenomena of detention area, bridging, and material accumulation on the silo wall when feeding and discharging, and even the material will rub with the measuring element when feeding and discharging, and there will be material hanging. Therefore, when measuring the solid level, how to select the type is also a problem.

When the radar level meter is used to measure the bulk material level, the diameter of most bulk materials is far less than 50mm, which is why the high-frequency radar level meter is the best choice for measuring the bulk material level. The measurement of powdery materials, especially the measurement of pneumatically transmitted powdery materials, although generally the dust has no impact on the radar level transmitter, a large number of dust will also produce scattering and affect the echo. At this time, the cable guided wave radar level meter can be selected. As the microwave is transmitted in the steel cable, the dust generated during the material transportation has no effect on the measurement. For the measurement of granular or blocky materials, the guided wave cable of the guided wave radar level gauge is easy to be damaged by hard materials, which is a problem encountered in the limestone bin level measurement. Therefore, the high-frequency radar level gauge must be selected, and the microwave emission angle needs to be smaller, because the higher the frequency of the micro wave, the shorter the wavelength of the microwave, to ensure that the emitted radar wave can be reflected back to the radar probe to the maximum extent on the rough solid surface, The smaller the emission angle, the smaller the probability of clutter and diffuse emission.

In addition, the solid material level has a certain angle of repose, and the measurement of solid material level is basically based on the diffuse reflection of radar wave on the rough surface. The reflection of microwave on the rough solid surface is related to the surface roughness of microwave wavelength. When the surface roughness is close to or greater than the wavelength of microwave, microwave will produce diffuse reflection, similar to the reflection of light wave on ground glass. Because of the diffuse reflection, most of the microwave energy is scattered, and only a small part of the energy is returned. It often leads to wave loss, so when measuring the solid material level, it will choose a stronger microwave energy than the liquid level gauge at the same distance.

Whether it is liquid level measurement or solid material measurement, there are all kinds of problems. Even in the cases we have encountered, one working condition gathers the above several complex situations. At this time, careful observation and calm judgment are required. The most important thing is to have certain professional knowledge to accurately select the model, and even in the future debugging of the instrument, it can be foolproof. This series is updated here for your reference only, and specific issues need to be considered.