A pressure switch is a form of switch that closes an electrical contact when a certain set fluid pressure has been reached on its input. The switch may be designed to make contact either on pressure rise or on pressure fall. Pressure switches are widely used in industry to automatically supervise and control systems that use pressurized fluids. It is used in a variety of industrial and technical processes. If a preset pressure is reached, then the pressure switch opens or closes a respective switch contact. Depending on the requirements, mechanical or electronic models can be used.

Pressure Switch

Uses of pressure switches

  • Uses in limiting pressure
  • It is used to operate as a safety valve, which vents out pressure when the pressure exceeds the upper limit.

  • Pressure switches are used in: Boilers, Gas compressor, Automobiles, pumps, steam turbine, Steam power plant.

How Pressure Switch Works?

  • The contacts in a pressure switch may be normally open or normally closed if the pressure is below the setpoint.

  • The contacts in a normally open (N.O) switch remain open until the pressure increases above the setpoint.Then the sensing element makes the contact snap to the closed position.The contacts open again when the pressure decreases below the setpoint.

  • The contacts in a normally closed (N.C) switch remain closed until the pressure increases above the setpoint.Then the contact snap open and remain open until the pressure decreases below the setpoint position.