The guided wave radar level meter has a different working principle compared to other radar level meters and has its own advantages and shortcomings. It is very important for users, especially purchasers, to know this information for proper selection. Below, the principle and advantages and disadvantages of the guide wave radar level meter are described below.

　　First, the guided wave radar level transmitter working principle

　　The working principle of the guided wave radar level meter is based on the time travel principle of measuring instruments, radar waves run at the speed of light, the running time can be converted into level signals through electronic components. When the pulse meets the material surface, it is reflected back and received by the receiver inside the meter, and the distance signal is converted into a level signal.

　　The working principle of ordinary radar level meter is transmitting-reflecting-receiving. Specifically, the antenna of the radar sensor emits an electromagnetic wave signal in the form of a beam, the emitted wave is reflected on the surface of the measured material, and the reflected return signal is still received by the antenna. Each point in the emitted and reflected beam is collected using ultrasonic sampling. The signal is processed by the intelligent processor to derive the distance between the medium and the probe, and sent to the terminal display for display, alarm, operation, etc.

　Second, the advantages and disadvantages of the guide wave radar level meter

　　1, the shortcomings of the guide wave radar level meter

　　(1) Not suitable for measuring corrosive and adhesive liquids, and not suitable for food grade requirements of high occasions

　　From the different working principles of the two types of radar level meter, it is known that the radar level meter is non-contact measurement, and the guide wave radar level meter is contact measurement. Therefore, it is necessary to consider the corrosiveness and adhesion of the medium, and the guided wave level transmitter is generally not used in the occasions with high food grade requirements.

　　(2) The installation and maintenance of guide wave radar level meter is inconvenient

　　Guided wave radar level meter in the measurement, too long wave guide rod (cable) for the installation and maintenance increased a lot of difficulties. And compared with the ordinary radar level meter which can be used interchangeably, the length of the wave guide rod (cable) of the guided wave radar level meter is fixed according to the working condition, and generally cannot be used interchangeably. Therefore, generally speaking, the selection and maintenance of the guided wave radar level meter is much more complicated than that of the ordinary radar level meter.

　　(3) The measurement distance of guide wave radar level meter is limited

　　The measurement distance of the magnetrol guided wave radar is not very long, while the common radar level meter is more commonly used in the tank of 30~40m, and can even measure up to 60m.

　2, the advantages of the guided wave radar level meter.

　　(1) more stable measurement of fluctuating media

　　In the tank with stirring, medium fluctuations, with the bottom fixed guide wave radar level meter than ordinary radar level meter is more stable, the advantages are also more obvious.

　　(2) More suitable for the measurement of materials in small tanks

　　When measuring the level in small tanks, due to the small installation measurement space (or more interferences in the tank), the general ordinary radar level meter is not applicable, while the guide wave radar level meter is not limited.

　　(3) Guide wave radar level meter is not limited by the high or low dielectric constant

　　The measurement principle of both ordinary radar level meter and guide wave radar level meter is based on the difference of dielectric constant of medium for measurement, because the wave emitted by ordinary radar level meter is dispersive, when the dielectric constant of medium is too low, the signal is too weak measurement will be unstable, while the wave emitted by guide wave radar level meter is propagated along the guide wave rod, the signal is relatively stable.

　In addition, the guided wave radar level transmitter generally has a bottom detection function, which can be corrected according to the measured value of the bottom echo signal to make the signal more stable and accurate.