VEGAPULS 69 radar sensor measures the level reliably in small dosing vessels

After extrusion, the product has to be dried according to moisture specifications. When the product leaves the dryer, it gets coated with essential fats and oils. At this point in the process, however, there have always been difficulties until now. Although this brand new, state-of-the-art facility was designed and built by the company’s own engineering team, one measuring point did not provide readings reliable enough to ensure a smooth, continuous process.

VEGA proposed a trial run with radar level sensor VEGAPULS 69. The higher 80-GHz frequency considerably extended the spectrum of applications for radar level measurement technology. An essential aspect of this success is the fact that the measuring instrument only requires an opening angle of 3° (previously 10°), which allows the measuring beam to glide right past internal fixtures or buildup on the vessel wall. In practice, the significantly tighter focusing of the transmitted signal offers a whole range of advantages, the most important being that the actual measuring signal can be better separated from interference signals, allowing even the smallest reflection signals to be detected.
Nevertheless: RCL Foods was particularly concerned about the low height of the container (only 2 meters) and the effective measuring range, which at 1.5 meters was even smaller. This is a problem that many users are familiar with, especially in applications with small apparatuses and vessels, for example in technical centres or pilot plants. The blocking distance (dead band) of the sensor, the size and design of the antenna or the measurement uncertainty at the bottom of the vessel normally pose some difficulties when it comes to obtaining a reliable measuring signal.
Although VEGAPULS 69 has a measuring range of up to 120 metres, it also copes well with small distances, such as those in the storage container of the South African company.

During installation it was necessary to use the existing mounting sockets, wherever possible without any modifications. This was not optimal, but due to the very good focusing of the sensor there were hardly any interfering reflections. After installation, the instrument was quickly set up via Bluetooth and smartphone. The measurement engineering team was positively surprised by the high quality of the measuring signals. Now, the level in the pellet container is reliably measured and can be kept constant. The continuous process of coating the food pellets now runs smoothly. Dust deposits from the dog food are also no problem for VEGAPULS 69. According to the company, the sensor hasn’t been touched since it was installed two years ago, neither for cleaning nor for maintenance. The level signal is reliable and accurate, ensuring production of a balanced dog food mix.