Radar level gauge
Principle: Emission - reflection - receiving is the basic working principle of radar level meter. The antenna of the radar sensor transmits the electromagnetic wave signal in the form of a beam. The transmitted wave reflects on the surface of the measured material, and the reflected echo signal is still received by the antenna. Each point of the transmitted and reflected beam is collected by ultrasonic sampling. After the signal is processed by the intelligent processor, the distance between the medium and the probe is obtained, and the terminal display is sent for display, alarm, operation, etc.
Features: The biggest feature of the radar level meter is that it has significant effect under harsh conditions. Whether it is toxic media, or corrosive media, whether it is solid, liquid or dusty, slurry media, it can be measured. In terms of measurement, it has the following characteristics:
1, continuous and accurate measurement
The probe of the radar level meter has no contact with the surface of the medium, which is a non-contact measurement, and can accurately and quickly measure different media. The probe is almost unaffected by temperature, pressure, gas, etc. (only 0.018% at 500 ° C and 0.8% at 50bar).
2. It has suppression function for interference echo
3, accurate and safe energy saving
The chemical and mechanical properties of the material used in the radar level meter are quite stable, and the material can be recycled, which has great environmental protection effect.
4, no maintenance and strong reliability
Microwaves are almost free from interference and are not in direct contact with the measuring medium, and can almost be applied to a variety of occasions, such as vacuum measurement, liquid level measurement or material level measurement. Due to the use of advanced materials, it is very durable for extremely complex chemical and physical conditions, and it can provide accurate and reliable, long-term stable analog or digital level signals.
5, easy maintenance, simple operation
Radar level meter has fault alarm and self-diagnosis function. Analyze the fault according to the error code prompted by the operation display module, determine the fault and eliminate it in time, make the maintenance and correction more convenient and accurate, and ensure the normal operation of the instrument.
6, wide range of application, can measure almost all media
From the shape of tank body, the radar level meter can measure the liquid level of spherical tank, horizontal tank, cylindrical tank, cylindrical cone tank, etc. From the function of tank, the liquid level in storage tank, buffer tank, microwave tube and bypass tube can be measured. From the measured medium, liquid, particle, slurry, etc., can be measured.
Summary:
In general, the radar level meter has a wide range of use and is a non-contact measurement method. Excellent material, low failure rate.
Guided wave radar level gauge
Principle: Guided wave radar level meter is a measuring instrument based on the principle of time travel. Radar waves run at the speed of light, and the running time can be converted into level signals through electronic components. The probe emits a high-frequency pulse that travels along the cable probe, and when the pulse hits the surface of the material, it is reflected back to be received by the receiver inside the meter, and the distance signal is converted into a level signal.
peculiarity
1, the steam and foam have a strong inhibition ability, the measurement is not affected;
2, not affected by the density of liquid, the degree of porosity of solid materials, temperature, dust during feeding;
3, low maintenance, high performance, high precision, high reliability, long service life.
Is there a difference?
The contact mode is different: the radar level meter is non-contact, and the waveguide level meter is contact. That is to say, in the case of higher food grade requirements, pilot type can not be used.
Different working conditions of the medium: guided wave radar type level meter needs to consider the corrosion and adhesion of the medium, and too long guided wave radar installation and maintenance is more difficult. Under the condition of low dielectric constant, the measurement principle of both radar and guided wave radar is based on the difference in dielectric constant. Since the emitted waves of ordinary radar are diverging, when the dielectric constant is too low, the signal is too weak and the measurement is unstable, while guided wave radar waves propagate along the guide pole and the signal is relatively stable. In addition, general guided wave radar also has the function of bottom detection. It can be modified according to the measured value of the bottom echo signal, so that the signal is more stable and accurate.
The selection is different: ordinary radar can be used interchangeably, and guided wave radar can not be used interchangeably because the length of the guide rod (cable) is fixed according to the original working condition, and the selection of guided wave radar is more troublesome than ordinary radar.
The measurement range is different: ordinary radar is more common in the application of 30, 40m tanks, and even 60m can be measured. Guided wave radar should also consider the stress of the wave guide rod (cable), which is also due to the reason of stress, the measurement distance of guided wave radar is generally not very long. However, guided wave radar has obvious advantages in some special working conditions, such as stirring in the tank and large medium fluctuation, the measured value of guided wave radar with fixed bottom in such working conditions is more stable than that of flexible radar; There is also the level measurement in the small tank, due to the small installation measurement space (or more interference in the tank), the ordinary radar is generally not applicable, then the advantages of guided wave radar appear.