The measuring system consists of a microwave emitter and a respective receiver. An emitting signal with a frequency of 24 GHz is focussed by an antenna system and emitted against the receiver. A medium in the path of rays damps this signal. This signal damping is detected by the receiver and converted into a switching signal. The adaption to the local conditions and the medium is easily possible by adjusting the sensitivity. Because microwaves can penetrate non-conductive products, a measurement through plastic vessels is possible. With metal vessels, mounting is carried out directly on the vessel or through suitable window materials such as for example plastic, glass or ceramic.
