Full definition
A pressure switch is an electromechanical device designed to monitor the pressure of gases or liquids within a system. It operates by opening or closing an electrical contact when a predetermined pressure level is reached. Pressure switches are typically equipped with adjustable set points and differential settings, allowing for fine-tuning based on specific operational requirements. The operational range of these switches can vary significantly, with many units capable of functioning between 0.2 and 600 bar, making them suitable for a wide variety of applications in pneumatic and hydraulic systems. The contacts can be configured in Single Pole Double Throw (SPDT) or Double Pole Double Throw (DPDT) arrangements to accommodate different circuit needs.
The contact rating of most pressure switches is generally rated at 250VAC with a maximum current of 5A, which is adequate for many industrial control applications. Additionally, pressure switches are often designed with a protection class of IP65, meaning they are dust-tight and can withstand low-pressure water jets, making them ideal for harsh industrial environments. Common applications include compressor start/stop control, hydraulic low-pressure alarms, and overpressure protection systems. Variants exist for specific uses, such as those rated for gas in hazardous areas (ATEX zones 1 and 2), fluid service, and steam applications to ensure safety and compliance with relevant industrial standards.
For compliance, many pressure switches adhere to the IEC 60947-5-1 standard, which governs the requirements for electrical devices used in industrial settings. This ensures that the devices meet necessary safety and performance benchmarks. Brands like Wika (PSM/PSA), Parker, Danfoss (KPS), SMC (IS1000), and Suco are recognized for their quality offerings in this category, providing reliable solutions tailored to meet diverse industrial needs.