Radar level sensors are corrosion-resistant devices used to measure the height of water levels, and the selection process involves several key factors to ensure that the selected device can meet the specific application needs. The following are the main steps and considerations for the selection of radar level sensors according to demand:
Define measurement requirements
- Medium characteristics:
Understand the dielectric constant, electrical conductivity, corrosion, temperature, pressure, density and other characteristics of the measured medium. These characteristics will directly affect the selection of radar level gauges, for example corrosive media may require the selection of non-contact radar level gauges to avoid direct contact. - Measuring range:
Determine the required measurement range, including the minimum and maximum measurement distance. This will help in selecting the appropriate antenna type and size, as well as determining the overall performance of the radar level gauge. - Accuracy requirements:
Determine the desired level of accuracy according to the purpose of measurement. For example, situations used for trade settlement or product handover may require higher levels of accuracy. - Environmental Conditions:
Consider the environmental conditions of the installation site, such as temperature, pressure, humidity, steam, dust, etc. These factors may affect the performance and reliability of radar level gauges. - Installation conditions:
Determine the installation location, installation method (such as top installation, side installation, etc.) and whether explosion-proof, windproof, rainproof and other functions are required.
Select the radar level gauge type
- Contact (guided wave) radar level gauge:
It is suitable for storage tanks with small space, small range, stirring inside the tank and internal obstacles.
It is not affected by the size of the dielectric constant, the fluctuation of the medium, fog and foam.
Suitable for corrosive media, foaming, stirring occasions. - Non-contact radar level gauge:
Suitable for harsh environment, large range, water vapor, steam, foam and other occasions.
Simple structure, long measuring distance, generally up to 30~40m or even 60m.
Not affected by the temperature, pressure, gas and other environment in the tank.
Select antenna form and frequency
Antenna form:
- Horn antenna: The integrated design components are not removable, high reliability, non-contact with the medium, no mechanical wear, long service life, large measurement range, high accuracy, good poly wave property, small blind area, small emission Angle. However, it is not suitable for the measurement of corrosive media.
- Rod antenna: the installation size is small, the signal is not affected by liquid level fluctuations and obstacles in the container, fog, foam, wall hanging and scaling have no effect on the measurement, can measure viscous liquid, suitable for temperature and pressure changes, but also suitable for corrosive media, hanging material, small space conditions.
- Parabolic antenna: narrow beam, good focusing performance, high measurement accuracy, antenna part drip design effectively avoid condensation and hanging phenomenon, not affected by high temperature, steam, powder, suitable for storage tanks with heating steam and powder and other conditions.
- Planar conical antenna: not affected by hanging material, weld, burr, etc., with purging function, can avoid steam, dust and other problems on the surface of the antenna condensation or crystallization and affect the measurement accuracy, suitable for high temperature, steam, powder and other storage tanks.
Frequency selection:
The frequency of the non-contact radar level meter is divided into C/K/W band. The C-band is 0~6GHz, the K-band is 20~26GHz, and the W-band is 70~80GHz. Radar level gauges with different frequencies have different measuring characteristics and application ranges.
Consider other factors
- Power supply and output signals:
Determine the desired power supply mode and output signal type (such as 4 to 20mA output or digital signal output). - Commissioning and maintenance:
Consider the ease of debugging and the ease of maintenance. Some radar level meters support a variety of debugging methods (such as programming module debugging, SOFT software debugging, HART handheld programmer debugging, etc.), which can simplify the debugging process. - Cost performance:
Under the premise of meeting the measurement needs, the radar level meter with high cost performance is selected as far as possible.
To sum up, the selection of radar level meter according to the demand needs to consider many factors such as media characteristics, measurement range, accuracy requirements, environmental conditions, installation conditions, antenna form and frequency. By comprehensively evaluating these factors, you can select the radar level gauge that best suits your specific application needs.