TDR Level Transmitter VF7
TDR is sometimes called ‘radar on a rope’ or guided wave radar; its contact-based measurement principle makes it ideal for reliable product monitoring. A probe or cable is lowered into the vessel from the top and continuously measures the level of product as it makes contact along its length. This level measurement technology is immune to dust, vacuum, humidity, foam, and variations in pressure, dielectric and temperature. Hycontrol’s VF Series TDR family offers a wide range of gauges and level indicators to meet almost every requirement.
The Reflex VF7 TDR microwave level control transmitter is ideal for the measurement of liquids, powders and granules up to a range of 35 m. The unit is unaffected by pressure, temperature, viscosity, vacuum, foam, dust, changes in dielectric constant or coating of the probe. VF7 can measure virtually any product in either Direct or TBF mode, utilising any one of the seven available probe types.
Pulses of low power microwaves travel along a conductor and are reflected at the point where they meet the product surface. The intensity of the reflection depends on the dielectric constant of the product. The higher the dielectric constant, the stronger the reflection will be, e.g. up to 80% for water.
The instrument measures the time between emission and reception of the microwave signal, which is proportional to the distance. TDR guided wave radar can be used in two different modes: for level measurement or interface measurement of two different liquids.
The VF7 can measure product with a dielectric rating as low as 1.1 Dk and can provide an accuracy of ±3 mm on liquids as standard. It is suitable for high-pressure applications up to 300 bar and can measure the interface between liquids such as oil and water. In short, VF7 is a powerful and accurate TDR unit for demanding applications.