Yet another attraction from switzer instrument ltd is a complete range of level instruments of delavan, usa. The operating principle includes, energizing the sensing probe with a radio frequency signal. When the process level changes, a change of capacitance takes place resulting in a very large change of frequency. This change is detected and compensated with preset values in the electronic measuring circuit. After proper amplification, this signal is used to either give a contact output or 4-20 ma dc signal to operate relays. Instruments are available either with complete or remote mounted electronics, single point or dual point level switches.Typical applications embodies detection of liquids,pumps sequencing, bulk solid materials,, free flowing materials, pumps controls high temperature handling with special purpose probes, special design to detect, ignoring material build-up, etc.
