What is the difference between radar level meter and guided wave radar level meter

Principle: Transmit - reflect - receive is the basic working principle of radar level meter.

The antenna of the radar sensor transmits electromagnetic wave signals in the form of a beam. The transmitted waves are reflected on the surface of the material being measured, and the reflected echo signals are still received by the antenna.

Each point in the transmitted and reflected beams is collected by ultrasonic sampling. The signal is processed by the intelligent processor to obtain the distance between the medium and the probe, and then sent to the terminal display for display, alarm, operation, etc.

Features: The biggest feature of radar level meter is that it is effective under harsh conditions. It can measure toxic or corrosive media, solid, liquid, dusty or slurry media. In terms of measurement, it has the following features:

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. (the impact is only 0.018% at 500°C and 0.8% at 50bar).

2. It has the function of suppressing interference echo

3. Accurate and safe energy saving

The chemical and mechanical properties of the materials used in the radar level meter are quite stable, and the materials can be recycled, which is environmentally friendly.

4. No maintenance required and high reliability

Microwaves are almost free from interference and do not come into direct contact with the measuring medium, so they can be used in almost all occasions, such as vacuum measurement, liquid level measurement or material level measurement. Due to the use of materials, they are very durable to extremely complex chemical and physical conditions, and can provide accurate, reliable and long-term stable analog or digital level signals.

5. Easy maintenance and simple operation

The radar level meter has fault alarm and self-diagnosis functions. According to the error code prompted by the operation display module, the fault is analyzed and promptly determined and eliminated, making maintenance and calibration more convenient and accurate, and ensuring the normal operation of the instrument.

6. Wide range of applications, can measure almost all media

In terms of the shape of the tank body, the radar level meter can measure the liquid level of spherical tanks, horizontal tanks, cylindrical tanks, cylindrical cone tanks, etc.; in terms of the tank body function, it can measure the liquid level in storage tanks, buffer tanks, microwave tubes, bypass pipes; in terms of the measured medium, it can measure liquids, particles, slurries, etc.

summary:

In general, radar level gauges have a wide range of applications, are non-contact measurement methods, are made of high-quality materials, and have a low failure rate.

Guided wave radar level meter

Principle: Guided wave radar level meter is a measuring instrument based on the time travel principle. Radar waves run 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 encounters the surface of the material, it is reflected back and received by the receiver in the instrument, and the distance signal is converted into a level signal.

Features

1. It has strong suppression ability against steam and foam, and the measurement is not affected;

2. Not affected by liquid density, looseness of solid materials, temperature, and dust during feeding;

3. Low maintenance, high performance, high precision, high reliability and long service life.

So is there any difference between them?

Different contact methods: radar level gauges are non-contact, while waveguide level gauges are contact. In other words, pilot level gauges cannot be used in situations where food grade requirements are high.

Different working conditions: Guided wave radar level meters need to consider the corrosiveness and adhesion of the medium, and it is more difficult to install and maintain a long guided wave radar. In low dielectric constant working conditions, the measurement principle of both radar and guided wave radar is based on the difference in 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 and the measurement is unstable, while the guided wave radar wave propagates along the waveguide rod, and the signal is relatively stable. In addition, general guided wave radars also have bottom detection functions, which can be corrected according to the measured value of the bottom echo signal to make the signal more stable and accurate.

There are differences in selection: ordinary radars can be used interchangeably, but guided wave radars cannot be used interchangeably because the length of the waveguide rod (cable) is fixed according to the original working conditions. As a result, the selection of guided wave radars is more troublesome than ordinary radars.

Different measurement ranges: Ordinary radars are commonly used on tanks of 30 or 40 meters, and can even measure up to 60 meters. Guided wave radars also need to consider the stress of the waveguide rod (cable). Due to the stress, the measurement distance of guided wave radars is generally not very long. However, guided wave radars have obvious advantages in some special working conditions. For example, if there is stirring in the tank and the medium fluctuates greatly, the measurement value of a bottom-fixed guided wave radar is more stable than that of a flexible radar. There is also level measurement in small tanks. Due to the small installation and measurement space (or the large number of interferences in the tank), ordinary radars are not applicable. At this time, the advantages of guided wave radars are revealed.