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1/2 Inch Water Flow Sensor SEN-HZ21WA

1/2 Inch Water Flow Sensor SEN-HZ21WA

Regular price Rs. 254
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  • This Water Flow Sensor SEN-HZ21WA is built for best compatibility with micrcontrollers like Arduino and Raspberry Pi.
  • It needs a working voltage of 5V and 15mA current.
  • It works at a range of 1~30L/min(m³/h) and working pressure of 1.75MPa.
  • The sensor comes with three wires - Red (5V-12V), Black (Ground) and Yellow (Output pulse).

1/2 Inch Water Flow Sensor SEN-HZ21WA

The SEN-HZ21WA water flow sensor is a device that is used to measure the flow rate of water. It consists of a turbine-type rotor that is placed in the water stream, and as the water flows past the rotor, it causes the rotor to spin. The sensor measures the speed of the rotor and converts it to a flow rate. The flow sensor has a digital output, which means that it provides a digital signal that can be read by a microcontroller or other host device.

The sensor is commonly used in applications such as irrigation systems, water treatment plants, and industrial process control. It is often preferred over other types of flow sensors because it is easy to install and has a low cost. The SEN-HZ21WA sensor is designed to be installed in a pipe with a diameter of 1/2 inch (12.7mm).

A pinwheel inside the sensor moves as the liquid flows through the sensor. A hall effect sensor within the sensor senses the rotation of the pinwheel and outputs a digital pulse for every rotation. By counting the pulses from the sensor, you can easily sense liquid flow through the sensor. This allows easy interface to microcontroller, Arduino, Raspberry Pi, etc.


  • Water testing
  • Water cooling systems
  • Measure liquid flow

Package Includes:

  • 1 x Water Flow Sensor SEN-HZ21WA


Sensor Type  Water Flow Sensor 
Model  SEN-HZ21WA
Test range 1~30L/min(m³/h)
Max. Working current 15mA
Working Voltage  DC 5V
Working pressure 1.75MPa
Hysteresis 0.01(%F.S.)
Insulativity Insulation Resistance≥100MΩ
Dimensions  57.8*37*37mm, G1/2 outside diameter
Weight  25 grams 

Shipping & Returns

  • All orders confirmed before 3 pm IST are shipped on the
    same day, barring rare pickup delays on holidays or disturbances
  • Delivery time in Metro cities is 1-3 days, Others it is
    3-7 days. It varies based on location, reliant on courier services
  • Return window: 7 days from receipt unless stated
    otherwise. No refunds/replacements after
  • Returns only for non-working/damaged products are accepted
  • Initiate return requests to our customer service team via Support ticket or contact us at +91-8123057137
  • Refunds are processed within 3-4 working days post inspection and approval.

For more details, please check our Shipping and Return Policy

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1. What are the applications of Water flow sensors?

  • Water flow Sensors are commonly used in HVAC systems, medical devices, chemical plants, and sewage treatment plants. The Flow sensors can detect leaks, blockages, pipe ruptures, and changes in liquid concentration due to contamination and dirt. A water flow sensor is installed at a water source or pipe to measure the water flow rate and calculate the amount of water that has passed through the pipe. The water flow rate is measured in liters or cubic meters per hour.

2. How do fluid flow sensors work?

  • As the liquid flows through the rotor, the rotor rolls, and its speed changes at different flow rates. And the hall sensor will output the corresponding pulse signal. A flow sensor is a component that measures the flow of a fluid, such as gas or liquid. Flow sensors use both mechanical and electrical subsystems to measure changes in the physical properties of a fluid and calculate its flow rate. Measurement of these physical properties depends on the physical properties of the liquid.