This useful basic flow meter can be used to measure the liquid located in different things such as solar, computer cooling, or gardening! It basically uses pinwheel sensor to help it in the measuring. Wondering why the pinwheel exactly? What makes it perfect for the mission is that it is used in a method that eventually lets the sensor to stay dry and safe. The method is simple, so first of all, the pinwheel has a little magnet attached, and there's a Hall Effect magnetic sensor on the other side of the plastic tube that can measure how many spins the pinwheel has made through the plastic wall.
The three wires that come along with the sensor are:
1. Red (5-24VDC power)
2. Black (ground)
3. Yellow (Hall effect pulse output)
You can easily keep track of the fluid movement through counting the pulses from the output of the sensor. Each pulse is about 2.25 milliliters.
Also, be careful don’t forget that this isn't a precision sensor. Fluid pressure, flow rate, and sensor orientation make the pulse rate vary a bit since it depends on them.
Note that whenever 10% precision or more is required, a better more careful calibration becomes essential. But in general, it works just fine for basic measurement tasks.
By the way, check this out, it’s very useful and fun, you’ll benefit from it: We have an example Arduino sketch that can be used to quickly test the sensor -