The new high frequency bulk solids radar level sensor from VEGA reaches yet further into the most challenging process application areas. An interview with Jürgen Skowaisa, product management Radar at VEGA, explains some of the background to the new VEGAPULS 69 solids radar sensor development.
Background to VEGAPULS 69
Radar level sensors are a proven a success story for bulk solids level, in some industries they have superseded measuring devices like electromechanical and ultrasonic in many sectors. Their immunity to pressure, temperature, in-flight dust, good focusing and no loss of echo – even during pneumatic filling, have seen the areas of application extended. Although users are increasingly adopting this microwave technology, it is still recognised that a level sensor which truly covers all applications has not yet been realised. Now, with a higher frequency and performance capability, the new VEGAPULS 69 radar designed for bulk solids comes a big step closer to this ideal.
This new level device operates with a frequency of 79 GHz, enabling a much tighter focusing of the transmission signal, this means it easily avoids interference from internal structures inside vessels. With latest generation microwave components, even the tiniest reflection signals can be measured. This means previously difficult to measure products with very poor reflective properties, such as high purity plastic powders or wood chips, can now be measured with confidence. VEGAPULS 69 also offers versatility over a much wider application range. With measuring capability from one or two metres…right up to 120 m, and an accuracy of ±5 mm, it still has enough performance reserves for unusual assignments, such as deep mine shafts or for fast response distance measurement on conveyor car systems.
Interview: Jürgen Skowaisa, product management Radar
Until now, you have kept a fairly low profile at the higher end radar frequencies for measuring instruments. Why have you now decided to offer the VEGAPULS69 solids radar level sensor at 79 GHz?
Skowaisa: With well over 100,000 radar sensors in the bulk solids sector alone, VEGA is very experienced in this field. In addition to the interesting, better focusing at a higher frequency, the limited dynamic range of the components was a reason why we have waited. In recent years, the 79 GHz radar technology has developed rapidly in the automotive industry. New components which can measure even the smallest signals and still have a very low energy requirement came onto the market. The time was ripe for launching a new radar sensor onto the market that meets our requirements.
Does the bulk solids world really need a new radar measuring instrument?
Skowaisa: Although we can cover a large part of the bulk solids sector, there are still applications in which better focusing or a greater dynamic range would be an advantage. If the technical possibilities exist, it is logical to exploit them to offer our customers a further possibility to solve their respective complex level applications. With the VEGAPULS 69 we are adding a further piece to the radar technology application area.
Does the VEGAPULS 69 now come close to the aim of a universal sensor in the bulk solids industry?
Skowaisa: That is certainly the case. The sensor is not only suitable for media with low reflection properties and larger measuring ranges but also covers all standard tasks. Therefore we have also created two different antenna systems for the different measuring tasks. Practice will show whether the sensors with the higher frequency will bring a better solution for all previous measuring tasks. More than 10 years of experience with the previous 26 GHz technology cannot be replaced with a new system overnight. Our focus for the development of the new sensor was on extending the range of application. The practical tests have been very positive so far – the tendency towards a universal sensor is certainly there with the new instrument.
However, there is certainly still no sensor that can cover all applications but the new VEGAPULS 69 is used in many different applications – from small bulk solids containers to large warehouses. To meet the different requirements, different versions have been used up till now. The new sensor now has enough power reserves for small measuring ranges and can also be used at heights up to 120 m for level and distance measurements.
The VEGAPULS 69 was launched late in 2014. How were the pre launch tests?
Skowaisa: We distributed a large number of sensors worldwide to get extensive feedback. Of course, many of our colleagues have the ambition to use the instruments where we have reached our limits with the previous technology, i.e. in especially difficult applications. We get detailed reports of every measurement and are often surprised what is possible with the new instruments. In addition to the good focusing, the great dynamic range, i.e. the possibility of detecting even extremely small reflection signals, is the great advantage of the new instrument.