Flow meters are gadgets that are utilized in measuring the rate of flow of any fluid and might be in the use of liquid or gaseous substance. It functions according to the opening and closing of different parts of the mechanism due to the flow of the fluid. There are various Sub types like turbine meters, which works on the principle that the fluid flow rotates a rotor; positive displacement meters, where the movement of fluid causes displacement of a fixed volume lying in the chambers of the meter; and paddle wheel meters which contains wheel that rotates due to flow of the fluid. These meters are appreciated for their robust constructions, and capabilities to supply ‘point of use’ accurate and independent electricity without the need for any sort of outside power.