The Difference between NEMA 4 and NEMA 4X Enclosures is that NEMA 4X Enclosures offer corrosion resistance
Published on: Jun 12, 2017
NEMA is an acronym for National Electrical Manufacturers Association. This organization gives electrical component enclosures ratings — such as NEMA 4X — based on their protective qualities. NEMA ratings specify whether an electrical component enclosure is safe for outdoor use, and what type of environmental conditions it can withstand.
Watertight. Must exclude at least 65 GPM of water from 1-in. nozzle delivered from a distance not less than 10 ft for 5 min. Used outdoors on ship docks, in dairies, and in breweries. X (as 4X) indicates additional corrosion resistance.
Among the range of NEMA ratings, the NEMA 4 enclosure is frequently utilized for its protection against the elements, including cold weather and the formation of ice on the exterior of the enclosure. The NEMA 4 offers an added degree of protection, and is the lowest-rated dustproof NEMA enclosure. In addition, it can protect against splashing water and even hose-directed water. However, it*s not explosion-proof, so it*s not suited for use in more hazardous applications
NEMA 4X Requirements
NEMA 4X is sometimes referred to as waterproof but this is not strictly correct because a NEMA 4X enclosure cannot be submerged in water; however, the enclosure must be resistant to an intense water spray without allowing any water ingress.
NEMA 4X enclosures must also pass a rigorous series of corrosion tests. These include 1200 hours of exposure to moist air containing carbon dioxide and sulfur dioxide and 800 hours of salt spray tests. Additionally, all enclosures must be dustproof and resistant to damage caused by the formation of ice. Although not mandatory, such enclosures are generally manufactured from stainless steel as this provides the ideal substrate to resist the corrosion and weathering tests required to achieve the NEMA rating.
Applications for NEMA 4X Enclosures
The range of applications for NEMA 4X enclosures is wide, extending from those where the enclosure must withstand extremely aggressive conditions to the ability to retain cosmetic appearance and functionality under all conditions. The resistance to corrosion, water sprays and adverse weathering represent three important applications for NEMA 4X enclosures