VRF
With the square flow rate controller VRF, both constant and variable flow rate control are easy.
The continual constriction in the cross-section of a measuring orifice with defined aperture ratio creates a static differential pressure (= active pressure) between the inflow and outflow sides during air flow.
With this method the flow rate depends only on the active pressure.
The active pressure is tapped in front of and behind the orifice using a pair of measuring tappings (plus and minus pressure tapping). Since it is not the dynamic pressure in the air flow which is measured, unlike in other active pre sure transducers (e.g. measuring cross), the risk of contamination of the measuring holes is lower. Depending on the make of the attached sensor, the measurement in the sensor can be dynamic or static.
- Universally suitable for the attachment of various controller makes and combinations of controllers, sensors and actuators for specific applications too.
- Possible combination with spring return or high-speed drives
- Corrosion resistant version of PPs for aggressive media, all parts within the air flow are made of plastic
- Easy adjustment, possible on site; damper setting can be read from outside
- Simple assembly
- For dynamic (VRF) and static (VRF-s) measurement
