A flow switch is a mechanical contact that turns on or off in response to flow or non-flow of a liquid, gas, air or water.The switch typically operates using a paddle that is displaced due to the force of the fluid that moves past it. Flow Switch is a special electrical device with a very simple design and a small size. But despite its simplicity, the flow switch plays an important role in countless applications.These electrical appliances are used to protect a pump and when the flow of air, gas or liquid through the specific line is to be monitored. The alarms can also be triggered using them whenever necessary. Flow switches can be specific to a type of system.