Understanding Pressure Switches: Applications and Functions

2023-04-07 10:53:01 By : Ms. Jufang Wang
: Understanding How It Works and Its Applications.

In the world of industrial automation, pressure switches play a vital role in ensuring that fluid pressure is closely supervised and controlled. These electrical devices are responsible for monitoring the pressures of fluids within pressurized systems and act accordingly to switch devices on or off.
Pressure switch - Wikipedia

What is a Pressure Switch?

A pressure switch is an electromechanical switch that is designed to open or close an electrical contact when it detects a certain set-pressure level on its input. They are commonly used for monitoring and controlling fluid pressure in liquids, gases, and steam systems.

Pressure switches are engineered with particular set-points that determine when the switch will activate or deactivate. The point at which the switch makes or breaks the contact can take place either on pressure rise or on pressure fall.

How Does it Work?

The inner workings of a pressure switch are relatively simple. The device typically consists of a spring-loaded diaphragm that is responsible for detecting changes in pressure. The diaphragm is connected to an electrical switch mechanism that is responsible for opening or closing a circuit.

When the fluid pressure in the system reaches a specific level, the pressure acting on the diaphragm will cause it to deflect, and this motion will activate the switch. When the set-point pressure is reached, the switch will close, and the device will remain in its activated state until the pressure is reduced.

Conversely, the switch will deactivate when the pressure reaches a certain level below the set-point pressure. The diaphragm will return to its resting position, and the switch mechanism will deactivate, causing the electrical circuit to break.

Applications of Pressure Switches

Pressure switches are widely used across different industries for various applications due to their versatility and reliability. Some of the common uses of pressure switches are outlined below:

Air Compressors

In air compressor systems, pressure switches are used to monitor and control the air pressure, ensuring that it remains within a specific range. The switch will activate the compressor when the pressure drops below the set-point and deactivate it once the desired pressure is reached.

Hydraulic Systems

In hydraulic systems, pressure switches monitor and control the pressure of fluids flowing through the system. This can help prevent potential damages to vital components, such as hydraulic motors and cylinders, which can be damaged by excess pressure.

Water Pumps

In water pump systems, pressure switches are responsible for turning the pump on and off. They regulate the water pressure, ensuring that it remains within a comfortable range. Pressure switches can also be used to detect problems in the water supply, such as low pressure or system leaks.

Industrial Automation

In industrial automation systems, pressure switches play a critical role in ensuring that fluid pressure remains within parameters. Systems such as hydraulic and pneumatic systems rely on pressure switches to control pressure levels in real-time and prevent potential damages.


Pressure switches are essential devices that help keep pressure levels under control in various systems. Whether in industrial or domestic settings, pressure switches play a vital role in ensuring that systems are functioning efficiently and preventing damages that can be costly to repair. Understanding how they work and their applications can help users make informed decisions when selecting a pressure switch for a particular system.