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As well as being non-contact, VEGAPULS can also be used as a completely non-intrusive system by virtue of the fact that microwaves can be transmitted through non-metallic vessel materials. A good example of this type of application would be in the manufacture of high purity acid with VEGAPULS mounted completely externally, without any direct mechanical connection to the vessel, thereby leaving the integrity of the vessel intact. Typical ideal window materials are PTFE, unleaded glass or ceramics.
A major performance advantage of VEGAPULS is its insensitivity to high temperature, or temperature variations within the process. Working process temperatures are virtually unlimited, and special cooling arrangements are available to keep the transmitter itself at reasonable operating temperatures. Typical high temperature applications include blast furnace ladel levels and clinker applications in the cement and power generation industries.
The presence of steam and/or dust over the measured product are of little concern to VEGAPULS. Even during pneumatic filling, the level of dusty products such as maize starch can be measured, as little attenuation of the radar pulse occurs, unlike other reflective systems.
Air turbulance or pressure variations within the vessel also has no effect on VEGAPULS as the transmission medium density does not influence the propagation of microwaves.
One of the benefits of the low frequency radar pulse transmitted by VEGAPULS, compared with other radar systems, is its superior penetration of foams above the product. Vega's experience of measuring through foams with pulse-radar has been good, although attenuation of the pulse radar signal is dependant on the moisture content and density of the foam.
As a general rule, liquid products can easily be measured with VEGAPULS. For solid products, good level measurement is achievable where the dielectric constant (DK) is greater than 2. Performance is not inflenced by changes in DK.
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