Selection Guide: How To Choose The Right Non-Contact Radar Sensor

Non-contact radar sensors are advanced level measurement instrument devices that measure levels without direct contact with the medium being measured. They operate by emitting and receiving electromagnetic signals through an antenna. Compared to contact radar level gauges, these devices offer several advantages, such as a larger measurement range, typically reaching up to 0-120 meters, while rod-type contact radar only has a range of 0-6 meters and cable-type contact radar ranges from 0-75 meters. Additionally, since they do not come into contact with the measured medium, they require less maintenance, and both installation and maintenance are relatively straightforward.

When selecting a non-contact radar sensor, several important principles need to be considered:

1.Dielectric Constant: The working principle of radar level gauges is based on the transmission, reflection, and reception of signals; thus, the dielectric constant of the measured medium is crucial for radar wave reflectivity. Generally, mainstream radar level gauges require the dielectric constant of the medium to be at least 1.5. It is not recommended to use radar level gauges for media with a dielectric constant below 1.5. In certain critical situations, such as liquefied petroleum gas with a dielectric constant of about 1.6, the echo signal can be enhanced by adding a guiding tube to meet measurement requirements.

2.Detection Accuracy: Different application environments have varying accuracy requirements for non-contact radar sensors, which can generally be divided into metering grade and industrial control grade. Metering-grade radar level gauges have an accuracy of ±1 mm, and frequency-modulated radar level gauges can respond quickly but tend to have higher power consumption and costs, usually adopting a four-wire system. Metering-grade radar is suitable for situations requiring precise measurement.

3.Explosion-Proof Rating Selection: When installing instruments in explosion-proof areas, it is necessary to choose the appropriate explosion-proof rating based on the area's explosion-proof classification and the type of flammable medium. Instruments of different explosion-proof types should not be mixed. In environments with gas explosion hazards, intrinsic safety or explosion-proof instruments should be selected, while dust or fiber explosion risk areas require dust explosion-proof instruments.

4.Reasonable Range Selection: Determine the required range based on actual working conditions and select the corresponding model of non-contact radar sensor. Devices with different ranges have varying emission power; the larger the range, the higher the power requirement. Using high-power devices in a small range environment results in energy waste, whereas using under powered devices in a large range environment will lead to inaccurate measurements.

5.Antenna Material and Model Selection: Choose the antenna material according to specific working conditions. For instance, high-temperature antennas should be selected when the medium temperature is high, and corrosion-resistant materials should be used in highly corrosive environments. In some cases, extended or specially designed antennas may be necessary to ensure that the non-contact radar sensor's antenna can be smoothly inserted into the tank.

The above outlines the characteristics and selection considerations for non-contact radar sensors. I hope this information is helpful to you.