Pepperl+Fuchs Blog

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.

When using the 5500 Type Z purge and pressurization system, you are given 3 vent options to choose from.  This gives you the option to choose a vent based on the needs of your application. The 3 models are:

To calculate the purging time on our 5500 series Type Z purge system, there are four variables that you need to know:

Most people are amazed that the dust from a number of everyday materials can become explosive under the right conditions: grains, sugar, metals, plastics, coal, coffee creamer, corn – just to name a few.

Because of this potential for explosion, dust hazards exist in many different industries:

• Food processing
• Pharmaceutical
• Automotive
• Textiles
• Cosmetics
• Refining