In the US, the two main organizations who set electrical safety standards for electrical enclosures are NEMA (National Electrical Manufacturers Association) and UL (Underwriters Laboratories). Although the standards for each enclosure type are independent from each other, the protection expectations are mostly the same. UL ratings are often described in more technical language, but after reviewing the summarized protections in the "NEMA and UL Ratings Equivalency Chart" below, you’ll quickly see that the enclosure protection expectations are almost identical.
If you typically buy standard electrical enclosures and boxes, you know that there are thousands of options available. However, when you need a few modifications to enclosures at high production volumes, it’s best to get help from a manufacturer who provides custom fabrication. HUI’s Industrial Business Development team specializes in these custom enclosures, so we thought we’d share some common modifications you can expect from custom metal fabrication manufacturers.