What are NEMA Enclosure Ratings?

The National Electrical Manufacturer Association (NEMA) publishes electrical and medical imaging standards and technical whitepapers for much of North America. NEMA believes that standards play an important role in the “design, production, and distribution of products destined for both national and international commerce.” NEMA standardizes electrical equipment to help consumers choose from safe, effective, and compatible electrical products.

NEMA provides standards and ratings for a wide variety of electrical supplies. Their enclosure ratings differ from their contact ratings and connector configuration types.

NEMA enclosure ratings, sometimes referred to as NEMA types, define the type of environment electrical enclosures can work in and signify the ability of an enclosure to withstand specified environmental conditions. NEMA enclosure types range from Type 1 to Type 13 with each offering varying degrees of protection. However, they do not necessarily go in ascending order. For example, a Type 4 offers stronger protections than a Type 12. Additionally, not every enclosure type works outdoors.

IP stands for ingress protection and indicates an electrical product’s ability to protect against the ingress of water and substances such as dirt and dust. IP ratings are an international standard that sets a guideline for electrical devices. They indicate how waterproof or dustproof an electrical device is.

NEMA ratings include protection standards against corrosion resistance and distinctions between hazardous and non-hazardous environments. NEMA ratings can also indicate protection against physical damage.