There is almost always more than one way to accomplish a particular job. For example, suppose you have a water tank, add water from other tanks, and you want to know when to add water. The obvious answer is to measure the water level in the tank, and there are many ways to do this. However, there are different ways here. A flow meter can be used to measure the amount of water leaving the tank. Suppose you know that the water is full, you can infer how much water is left.
There are many ways to measure traffic. The FM-HL3012 uses a Hall effect sensor to measure the Yrotation equivalent to a waterwheel. When the water turns, it counts the click of the wheel. However, this method is more complicated. If you want to use a simple method of measuring the water level, we recommend the photoelectric level sensor of EPTSensor. For specific usage, please click: http://www.eptsensor.com