The alternative: Vortex sensor instead of vane
Turbulence as a measure for the flow
Behind a blunt body (or shedder) integrated in the measuring pipe, the flowing medium generates swirling vortices depending on the velocity. These vortices are detected by a piezoceramic sensor. If the cross-section is known, the number of the vortices allows to determine the flow rate.
This flow rate measurement principle, known as vortex (or vortex shedding) principle, is almost independent of pressure and temperature fluctuations of the medium. It allows a simple design and thus a low-cost production of sensors for flow rate measurement.
The current flow and temperature are output as standardised current signal (4...20 mA), as frequency signal, switching output or via IO-Link as option.