A pressure switch is an automatic control device that monitors system pressure and turns an electrical circuit on or off when a preset pressure level is reached. Unlike a pressure sensor that provides continuous readings, a pressure switch is designed for decision-making — it triggers actions such as starting a pump, stopping a compressor, activating an alarm, or shutting down equipment to protect the system.

Pressure switches are widely used in pneumatic and hydraulic systems, compressors, boilers, HVAC, water pumps, and industrial machinery where maintaining safe pressure limits is critical. They help prevent overpressure, equipment damage, and unsafe operating conditions while also improving energy efficiency by ensuring machines only run when needed. Pressure switches are simple, reliable, and essential for safe and automated pressure control.