Rotating Vane flow technology is also commonly known as paddle-wheel technology. There are a few different variations of rotating vane technology. All of them involve a rotor or paddle-wheel that spins on an axis due to media flow. The difference between the types lies in the paddle-wheel and flow orientation.

True "paddle-wheel" technology has flat rotor blades that behave in a manner similar to a riverboat paddle-wheel. The flow contacts the rotor in an "overshot" manner. Turbine type models have angled or twisted rotors that essentially face the flow straight on, or in other words, the flow is parallel to the axle. This type of motion is replicated in boat motors, wind mills, airplane engines, and simple house fans. Pelton-wheel technology is very similar to the "paddle-wheel" as it also has flat rotor blades, but the flow is concentrated around most of the paddle, not straight across it which gives it higher accuracy than the "paddle wheel type".

In any of these types, the rotational speed of the wheel or blade is a direct function of the volumetric flow rate. This motion is detected electronically by a magnetic pick-up, an inductive pick-up, or an optical detection. A frequency output is then either used directly or converted to a proportional analog signal.