Pepperl+Fuchs Blog

The 7500 series is a type Z/Ex pzc purge and pressurization system that enables non-rated electrical equipment to be used in hazardous areas. The 7500 series is a certified system for UL Class I and II/Div. 2 as well as for Zone 2/22 hazardous locations. A complete 7500 purge and pressurization system requires a control unit, a manifold valve, and a vent. It can be configured as a manual or fully automatic system. This blog article shows you how to configure the 7500 system components, i.e. control unit, manifold valve, and vent.

Dust explosion disasters like the one at the Imperial Sugar Company refinery in Georgia, USA, resulted in several congressional hearings in the USA that cited the US Occupational Health and Safety Administration (OSHA) for not enforcing worker protection regulations. As a result, OSHA has since identified at least 30,000 plants in the USA as having potential problems from dust hazards. It is also estimated that around 2,200 dust explosions happen throughout Europe each year. As the industry continues to become aware of this potentially devastating problem, they will need solutions that protect their workers, plants, and the surrounding environments. Read in our blog article, where combustible dust atmospheres may occur and how these could be prevented.

Unlike containment or prevention, purge and pressurization separates general-purpose equipment from the surrounding potentially explosive atmosphere using a standard, lightweight enclosure. The enclosure is then purged with industrial-grade air or inert gas to eliminate all hazardous gas inside. Then, the flow is decreased to maintain a pressure higher than that of the dangerous external atmosphere. This prevents the flammable mixture from coming in contact with the components inside the enclosure.

Pepperl+Fuchs offers an array of purge systems. The 2000 series is a legacy system that is now obsolete, and its recommended replacement is the 6000 series—the latest Type X purge system from Pepperl+Fuchs.

Specialized protective equipment has to be used in environments that contain gases, vapors, combustible dusts, and fibers to prevent these materials from catching fire or exploding. Purge and pressurization systems help control these explosion hazards by segregating the electrical equipment inside of an enclosure from the surrounding potentially explosive atmosphere. An economical alternative to heavy and expensive explosion-proof enclosures, purge and pressurization systems pressurize enclosures with clean, dry compressed air or inert gas so hazardous gas or dust cannot get in.

Combustible Dusts are a known hazard in a number of industrial fields. Recognizing dust as a potential hazard and taking the steps to mitigate the risks present are critical to the safety of your facility. The recently updated NFPA® 652: Standard on the Fundamentals of Combustible Dust is a useful resource for addressing combustible dust hazards and conducting a dust hazard analysis (DHA) within your facility.

On Friday, August 25th, Hurricane Harvey hit the South Texas coast. Consequently, the storm front struck our new manufacturing and warehouse building in Katy, Texas. High wind from a hurricane tornado damaged our roof structure, pulling air handling units from the roof and allowing water to enter the building.

When installing a purged control panel or industrial HMI in a hazardous location, power supplied to the control panel must be regulated so that components are not energized before the panel is protected by a purge cycle.

The maximum size of an Ex pz purge enclosure is determined by the pressure and flow that can be reached inside the enclosure. For this 'how to' post, I'll use our 5500 series purge system for the examples.

Depending on your application, there are three vent options that you can use with your system. The EPV-5500-…-01, EPV-5500-…-02, or EPV-5500-…-03. Each vent opens at a different back pressure and has different flow rates, which are listed below.

Integrating complex electrical systems and components into hazardous areas typically requires combining different methods of industrial explosion protection to achieve a safe and certified solution. Our Solution Engineering Centers have the ability and the experience as a system integrator for solutions going into Zone 1 and 21 or Zone 2 and 22 areas. Our ATEX and IECEx certificates offer great flexibility, allowing  unique solutions for the challenges of putting complex electrical equipment in hazardous locations around the world.