Saier HZ41WA Water Flow Sensor (0.25–3 L/min) - DC 4.5-18V

The HZ41WA provides flexible output options. It generates a pulse frequency signal (digital output) proportional to the flow rate, which can be counted by a microcontroller. It also provides a conditioned analog voltage output, allowing for direct ADC reading on systems like Arduino or PLCs for continuous flow rate monitoring.

This sensor operates on a wide DC voltage range from 4.5V to 18V, making it compatible with common 5V and 12V systems. Connect the VCC pin to your power source (e.g., Arduino 5V, 12V adapter), GND to ground, and ensure your supply can deliver up to 15mA. Always use a stable, regulated power supply for accurate readings.

While primarily designed for water and similar low-viscosity liquids, the turbine mechanism is also suitable for clean, dry gases. However, accuracy specifications are calibrated for liquids. For gas applications, ensure the medium is non-corrosive and free of particulates, and consider recalibrating the pulse count or analog output against a known gas flow standard.

For digital interface, connect the signal output pin to a digital interrupt pin on your Arduino to count pulses per unit time. For analog interface, connect the output to an analog input pin (ADC). Use the provided conversion formula (typically flow rate = pulse frequency / K-factor) from the datasheet to calculate the actual flow rate in your code.

The sensor has a typical accuracy of 5-8% under standard conditions. For best performance, install it in a straight pipe section (at least 10x pipe diameter upstream and 5x downstream) to ensure stable, non-turbulent flow. Avoid air bubbles in the liquid, as they can affect the turbine rotation and cause measurement errors. Regular maintenance is recommended for long-term accuracy.