Radar Level Sensor
Transmit-reflect-receive is the basic working principle of radar level sensor.
The antenna of the radar sensor emits electromagnetic wave signals in the form of beams, and the emitted waves are reflected on the surface of the measured material, and the reflected echo signals are still received by the antenna.
Each point in the transmitted and reflected beams 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 it is sent to the terminal display for display, alarm, operation, etc.
The biggest feature of the radar level sensor is its remarkable efficacy under harsh conditions. Whether it is a toxic medium or a corrosive medium, and whether it is a solid, liquid, dusty, or slurry medium, it can be measured. In terms of measurement, it has the following characteristics:
1. Continuous and accurate measurement
The probe of the radar level sensor has no contact with the surface of the medium, which belongs to non-contact measurement, and can accurately and quickly measure different media. The probe is hardly affected by temperature, pressure, gas, etc. (the influence is only 0.018% at 500°C and 0.8% at 50 bar).
2. It has the function of suppressing the interference echo.
3. Accurate and safe energy saving
The chemical and mechanical properties of the materials used in the radar level sensor are quite stable, and the materials can be recycled, which is extremely environmentally friendly.
4. No maintenance and strong reliability
Microwave is almost immune to interference and does not directly connect with the measurement medium, so they can be used in almost all kinds of occasions, such as vacuum measurement, liquid level measurement or material level measurement, etc. Due to the use of advanced materials, it is durable in extremely complex chemical and physical conditions, and it can provide accurate, reliable, long-term stable analog or digital-level signals.
5. Easy maintenance and simple operation
The radar level sensor has fault alarm and self-diagnosis functions. Analyze the fault according to the error code prompted by the operation display module, determine the fault in time, and eliminate it, making maintenance and calibration more convenient and accurate, and ensuring the normal operation of the instrument.
6. It has a wide range of applications and can measure almost all media
From the shape of the tank body, the radar level sensor can measure the liquid level of spherical tanks, horizontal tanks, cylindrical tanks, cylindrical cone tanks, etc.; from the tank function, it can measure the liquid level of storage tanks and buffer tanks, microwave tubes, and bypass tubes to measure liquid levels; from the perspective of the measured medium, it can measure liquids, particles, slurry, etc.
Generally speaking, the radar level sensor is widely used and is a non-contact measurement method. Excellent material, low failure rate.
Guided Wave Radar Level Sensor
The guided wave radar level sensor is a measuring instrument based on the principle of time travel. The radar wave runs at the speed of light, and the running time can be converted into a level signal through electronic components. The probe emits a high-frequency pulse and propagates along the cable probe. When the pulse meets the material surface, it is reflected back and received by the receiver in the instrument, and the distance signal is converted into a level signal.
1. It has a strong ability to suppress steam and foam, and the measurement will not be affected;
2. Not affected by liquid density, the porosity of solid materials, temperature, and dust during feeding;
3. Low maintenance, high performance, high precision, high reliability, and long service life.
What is the difference between a radar level sensor and a guided wave level gauge?
1 The contact method is different: the radar level sensor is non-contact, while the waveguide level sensor is contact. That is to say, the pilot type cannot be used in occasions where food grade requirements are high.
2. The working conditions of the medium are different: the guided wave radar level sensor needs to consider the corrosion and adhesion of the medium, and the installation and maintenance of the guided wave radar are more difficult. In the working condition of low dielectric constant, the measurement principle of both radar and guided wave radar is based on the difference in the dielectric constant of the medium. Since the waves emitted by ordinary radar are divergent, when the dielectric constant of the medium is too low, the signal is too weak to measure. Stable, while the guided wave radar wave is relatively stable when the signal propagates along the probe. In addition, the generally guided wave radar also 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.
3. The selection is different: ordinary radars can be used interchangeably, while guided wave radars generally cannot be used interchangeably because the length of the guide rod (cable) is fixed according to the original working conditions. Affected by this, the selection of guided wave radars is more difficult than ordinary radars. Radar trouble.4. The measurement range is different: it is common for ordinary radar to be used on tanks of 30 and 40m, and it can even measure up to 60m. Guided wave radar also needs to consider the force of the guiding rod (cable), which is also due to the force. Generally, the measurement distance of guided wave radar will not be very long. However, guided wave radar has obvious advantages in some special working conditions, such as stirring in the tank and large fluctuations in the medium. In such working conditions, the measured value of the guided wave radar fixed at the bottom is more stable than that of the flexible radar; there are also small tanks. For level measurement, due to the small installation and measurement space (or many disturbances in the tank), ordinary radars are generally not applicable, and the advantages of guided wave radars are revealed at this time.