Rittal Blog

Understanding Arc Flash and How to Limit Exposure With Industrial Automation Enclosure Systems

December 12 2022 by Rittal North America LLC

Even with advancements in technology and processes, today’s industrial space still comes with some inherent hazards manufacturers must mitigate to help ensure the safety of their personnel, equipment, and production facilities. One safety hazard of high concern in working with electrically charged equipment like industrial control panels is arc flash hazards. Understanding what arc flash is and how it is caused can go a long way for manufacturers to help protect employees. 

Understanding the basics is the first step in arc flash presentation and safety. However, manufacturers can implement additional solutions to help keep arc flash hazards at a minimum. Using an industrial automation enclosure system that is designed to separate people and potential hazards can help to create a safe, stable, and reliable production environment that can help to reduce the chance of personal injury, damage to equipment, and costly downtime from equipment repair or replacement. 

Let’s briefly define the how and why of arc flash before discussing how the right industrial enclosures and power distribution systems can help manufacturers avoid the hazards of arc flash.

What is arc flash, and how does it happen?

According to OSHA, an arc flash is a phenomenon where a flashover of electric current leaves its intended path and travels through the air from one conductor to another or to the ground. The results are often violent and when a human is in close proximity to the arc flash, serious injury or death can occur. 

In addition to being under-protected and exposure to improperly insulated or high-voltage electrical currents, causes of arc flash include dirty or inadequately secured electrical connections, electrical equipment condensation, corrosion, or equipment failure. 

Arc flash events are characterized by extreme heat, intense light, and a violent pressure blast. Common areas for arc flashes to happen include highly energized areas such as control panels, disconnects, bus switches, motor controls and starters, and switchgear. In most of these incidents an arc flash occurs when personnel fail to ensure equipment has been properly de-energized. 

The intense heat from an arc flash causes an expansion of air that results in essentially an explosion of energy that can propel shrapnel, tools, and workers through the air. Workers exposed to an arc flash can sustain serious injuries typical of an explosion: severe burns, loss of vision and hearing, broken bones, head trauma, and even death. 

An arc flash event is a major concern for any application that incorporates electrical equipment with a current; risks can be even greater in plants where production takes place on a 24/7 basis or in challenging deployments with extreme environmental conditions.

The right automation solutions to help reduce the chance of arc flash

According to OSHA, there are between 5 to 10 arc flash incidents every day in the United States. A large percentage of these incidents can be attributed to human error, but manufacturers can make some strategic choices in how they build their automation framework to help decrease the likelihood of arc flash. The best way to avoid exposure to an arc flash is to prevent access. Isolating the high-voltage controls equipment from areas where employees are working is key. 

With unparalleled configuration options and flexibility via interchangeable panels, plus easy mounting plate assembly and installation, modular enclosures allow for fast and simple customization based on space constraints or factory floor layout. 

This flexibility can help to decrease the potential of an electrical current getting caught between inadequate conductors  because it allows manufacturers to house  high-voltage and low-voltage equipment within the same enclosure system by utilizing partition walls and individualized compartments. The controls layout can be designed so that power will be isolated to a separate section which can follow lock out tag out protocols, have proper signage, and limit entrance into the hazardous section. 

To further reduce the possibility of electrical fault, there are modular enclosures in today’s market that incorporate safety features specifically engineered to help prevent arc flash. The Rittal TS 8 flange mount disconnect modular enclosure utilizes mechanical interlocking doors to prevent entry while the enclosure is energized. In addition, the TS 8 flange mount disconnect modular enclosure easily accepts most third party disconnect handles which helps to implement lock-out-tag-out practices to further protect personnel from arc flash hazards. 

Modern power distribution systems are also key in helping to prevent arc flash. The IEC 61 439-1 sets the global standard for low-voltage power distribution within an enclosure to ensure manufacturers are not reliant on outdated power distribution systems that can increase the chance of electrical fault. Busbar power distribution — which has emerged as the power solution of choice for manufacturers around the world — is not only compliant with the IEC and UL standard but is also seamlessly compatible with modular enclosures.

No matter the industrial application, the right combination of insight and industrial automation framework can help manufacturers minimize the chance of arc flash and create an infrastructure built on protection and productivity.

Explore Rittal’s Power Isolation Enclosure Selector Tool to configure the right enclosure to help prevent arc flash. 

Categories: Industrial Automation