Often, an arc-flash event is triggered by operator movement or contact with energized equipment — this is a particular threat when faults occur within an enclosure. A phase-to-ground or phase-to-phase fault that results in an explosion can cause fatal injuries and severe burns, and produce considerable damage.

To protect operators, NFPA 70E standards require a “flash protection boundary.” Only qualified personnel with extensive protective clothing and equipment, including fire-resistant suits and hoods along with non-conductive wands, can access electrical equipment enclosures capable of generating an arc flash. Maintaining NFPA 70E compliance by such conventional methods can be costly both in terms of resources and efficiency.

One alternative is an enclosure system, where an external disconnect enclosure is mounted to a floor-standing cabinet. This isolates incoming power from the main control cabinet to mitigate the danger of arc flash occurrences when working on interior components.

Such systems like Hoffman Enclosure’s Arc Flash Safety System are designed to reduce the risks of arc flash explosions by providing convenient access to enclosed components without opening an enclosure door. Protection and production are enhanced while costs are greatly reduced.

Hoffman’s system is configured with the following safety features:

a) Data Interface Port for exterior programming access;

b) Folding shelf for a sturdy laptop or test equipment work surface;

c) Viewing windows/window kits, which allow operators to view PLC functions, fuse operation and other status lighting;