Measure principle and usage scenario

Measurement Principle

LORRIC’s paddlewheel flow meter utilises AxleSense technology, which detects flow via the rotation of an internal magnetic component embedded within the paddlewheel. A signal is transmitted with every blade rotation within a margin of 3 degrees, resulting in denser signal output and significantly improved resolution. This design ensures highly sensitive detection, even at flow velocities as low as 0.3 m/s, allowing rapid and continuous signal acquisition. The result is faster flow measurement response and industry-leading linearity of 0.5% of full scale.

In addition to enhanced sensitivity, AxleSense enables the flow meter to detect bidirectional flow, providing directional feedback through positive or negative values.

Due to the friction between the paddlewheel and the shaft core, the thrust provided by the fluid is limited at low speeds. Paddlewheel flowmeters used in water generally cannot measure flow rates below 0.3 m/s. Therefore, the main unit may display a flow rate of zero.

If you need to measure flow rates below this threshold, you may consider using the FP-AS510 paddlewheel flowmeter.

As this product relies on magnetic sensing and mechanical rotation, it is essential to avoid the presence of solid particulates, magnetic substances, crystallisation, and water hammer in the fluid. Additionally, strong electromagnetic fields near the main unit should be avoided.

The presence of solids, magnetic materials, crystallised deposits, or water hammer may cause the paddlewheel to become jammed or significantly reduce its lifespan. A notable feature of AxleSense technology is the ability to generate an alert signal if the paddlewheel is lost due to external force or wear.

Strong magnetic interference near the main unit may cause flow reading inaccuracies or prevent the paddlewheel from rotating. Interference sources should be eliminated.

The paddlewheel and axle are deliberately engineered with a relatively large clearance. As flow velocity increases, the resulting rotational noise from the paddlewheel will also increase — this is a normal operational characteristic.

Intended Application

This product is designed for industrial flow measurement in full-pipe systems carrying relatively clean liquids. The installation location should promote stable and fully developed flow conditions. Fluid temperature must be kept within 0–50°C, in accordance with the temperature limitations of the PVC tee and paddlewheel assembly. The flow meter housing is rated IP65 for water resistance, but is not suitable for submersion.

The enclosure is made of polycarbonate (PC), which offers limited chemical resistance and should not be exposed to high concentrations or prolonged contact with aggressive chemicals.

Selection of pipe fittings and paddlewheel materials should take into account the following factors:

• Temperature resistance

• Chemical compatibility

• Pressure tolerance