How Does a Pressure Switch Work?

Pressure Switches are part of our product range here at Variohm.

What is a Pressure Switch?

A pressure switch is a device used to monitor the pressure in a given environment and give an alert when the pressure level reaches a set limit. There are pressure switches suitable for use in monitoring liquid pressure or air pressure.

The primary function of a pressure switch is for monitoring and detection of pressure. They cannot give an accurate real-time pressure reading like a pressure transducer, instead they are used to ensure pressure does not reach a certain limit.

How Does a Pressure Switch Work?

A pressure switch consists of a pressure port (or ports depending on the type of pressure switch) an internal diaphragm and a spring. As pressure enters the port, the diaphragm is deflected into the spring. If the force entering the pressure switch is greater than the pre set force exerted by the spring, then switch contacts will touch causing the switch to operate. This will either break or make the electric circuit depending on the switch.

Pressure Switches can be used to monitor either a pressure rise, or a pressure drop depending on the pre-set level and the current level within the environment.   

An adjustment screw can be used to alter the set level of the switch allowing switches to be set at different applications for different applications.

Pressure Switch Uses

Pressure switches are usually used to alert the user that something has reached a limit as part of a high/low alarm system. This could be on a tank, a liquid dispensing machine or to indicate a blockage in an air flow. Some of the applications we are often approached for are:

• Medical applications – monitoring levels in oxygen tanks, breathing apparatus, breathalyser alarms, compression units
• Automotive applications – air filters, vacuum systems
• Agriculture – crop dusting machines
• Domestic use – drink dispensing, white goods
• Industrial use – extractor fans, filtration equipment, water pumps, gas compressors, HVAC applications

Pressure Switches from Variohm

We have a range of pressure switches available to view on our website. Our selection includes our own range – the EPS range, as well as a range from our trusted suppliers. This can be pre-set before use and are light weight.

For more information please contact us.