VZVA Positive Displacement Flow Sensor

SIKA’s gearwheel type VZVA positive displacement flow sensor records volume flows of liquids with both high and changing viscosities. The high-precision sensors work according to the displacement principle. The high resolution combined with reliable measurement accuracy makes the sensors especially useful for applications involving the measurement of small and minimal volumes.

A very precisely adjusted gear pair within the casing forms the measuring element. The inflowing medium causes the gear pair to rotate. Contactless sensors scan the rotary motion. Since each tooth generates a pulse, this results in a very high resolution. Consequently, even the smallest volumes can be measured or dosed precisely.

The measurement unit contains two pick-offs that are circumferentially offset by ¼ of a tooth pitch to generate a two-channel flow-proportional frequency signal. Suitable processing of the signal provides a higher resolution and the option to identify the flow direction.

The maximum pressure drop should not exceed 16 bar. This limits the measurement range of high viscosity media (see pressure drop diagrams). The measurement accuracy increases with an increase in viscosity of the media.