The measures to reduce the measurement error of radar level gauge

1. Install isolation device to reduce AC interference. In view of the high voltage of the power supply and the interference of the signal in the transmission process, two parallel and reversely arranged isolation modules are installed between the power supply and the instrument to solve the above problems. The isolation transmission accuracy reaches ±0.1% FS, which effectively reduces external interference while maintaining accuracy. Its advantage is that it can be switched between active and passive, and the passive function can directly provide 24VDC power supply to the two-wire radar level gauge on site without an external power supply, with fast response, low power consumption and low interference. The original signal wire used shielded wire, which can effectively reduce common mode interference, but it is recommended to use shielded twisted pair cable for better anti-interference effect.

2. Choose a reasonable installation position and angle according to the analysis of the measurement conditions to improve the accuracy of the measurement. Aiming at the problem of the installation position of the radar level gauge, the same type of radar level gauge was installed at a position 1.5m above the transfer bin from the side of the two feeding belt discharge openings, and the horn antenna was installed at an appropriate angle during installation. Make the radar wave to face the blanking point of the unloading port in the circle area with the center radius of 0.5m-1m. At the same time, the radar level gauge on the finished product storage bin should not be installed in the center of the arched tank, otherwise interference echo will cause signal loss. It cannot be installed very close to the tank wall, and the best installation position is 1/2 shift of the radius of the vessel. The minimum distance from the tank wall is 30m.

3. Keep the probe of the radar level gauge clean to avoid dust and damp scars on the probe. In view of the current dust accumulation on the transmitter head, disassemble the existing radar level gauge, attach a layer of plastic film to the antenna horn, and regularly clean the dust on the horn antenna to ensure that there is no dust on the transmitter head and ensure measurement Precision and stability.

4. Digital filtering reduces interference. There are a variety of interference signal processing problems in the reflected signal. In the measurement process of the radar level gauge, the processing of real echoes and the effective identification of false echoes are the key factors that affect the accuracy of the radar level gauge. Due to the influence of electromagnetic waves and random environmental noises of on-site electronic equipment, The detection signal must contain more interference echo signals.

Well-known brands of radar level gauge

E+H, whose full name is Endress+Hauser, was founded in 1953 and is headquartered in Switzerland. Its business covers process and laboratory automation fields. In the field of process automation, E+H provides products, services and solutions for flow, level, temperature, pressure, process analysis and data management. In the field of laboratory automation, it mainly provides instruments for laboratory analysis and life sciences.

FMR230, FMR231, FMR244, FMR245 compact radar level transmitter

Emerson, founded in 1890, is a century-old factory. This company has two main business modules, namely automation solutions and commercial and residential solutions. Compared with the previous companies, Emerson has diversified businesses and diversified coverage.

Rosemount 5300 Guided Wave Radar Level Transmitter

VEGA is a manufacturer of level measuring instruments and pressure measuring instruments established in Germany in 1959. Its typical products are a new generation of compact continuous level measuring instruments developed based on 80GHz technology. Compared with the previous two imported radar level gauge companies, VEGA started relatively late, but VEGA has distributors in many countries, which is regarded as the leader of the rising star.

Vega Vegaplus 64 Radar Level Meter

Vega Vegaplus 69 Radar Level Meter

Siemens AG, Germany, Founded in 1847,is a global leader in the field of electrical and electronic engineering.

Siemens SITRANS LR460 Radar Level Transmitter