A pressure switch provides on-off switching capability when a certain pressure is reached on its input. The switches make electrical contact to open, close or adjust an internal contact based on a previously programmed level of functioning. A pressure switch basically uses a diaphragm or bellows as the sensing element. The movement of this sensor element is used to activate one or more switch contacts to initiate a control alarm. Pressure switches can be categorized into two types; electromechanical and solid-state pressure switches. Pressure switches are commonly used in industrial applications such as in Boilers, Gas compressors, Automobiles, pumps, steam turbines, Steam power plants as part of monitoring and alarm systems in process control applications and industrial automation.