Additional Information on NEMA 4X Enclosures

Most of the time, NEMA 4X is regarded as a waterproof electrical enclosure but it cannot be also submerged in water. There is a specific electrical enclosure for that which are NEMA 6 and NEMA 6P enclosures. But this enclosure is resistant to any intense water that protects the electrical equipment from allowing any water ingress.

General speaking, NEMA 4 is manufactured from carbon steel and aluminum, which can be rust, on the other hand, NEMA 4X is from stainless steel. Therefore, NEMA 4x provides corrosion resistance, but not from NEMA 4. Some manufacturers provide powder coated aluminum, which can provide corrosion resistance. They also offer powder coated carbon steel too. However, from my experience when it is damaged, that spot will be rust.

NEMA 4X Quality Tests

In line with this, NEMA 4X enclosures should also pass several and rigorous corrosion tests that measure its quality. These include exposing the enclosure to 1200 hours of exposure to corrosion-inducing environments such as moist air containing carbon dioxide and sulfur dioxide. Both compounds are proven to hasten the process of oxidation in metals thus resulting in corrosion. The enclosure should also withstand the 800 hours of salt spray tests, this mimics rainwater which also induces corrosion among metals.

NEMA 4 and 4X Enclosure Summary

Additionally, these enclosures should be dust-proof and damage resistant caused by ice formation. Majority of these electrical enclosures are manufactured from many grades of steel.

• Type 4X from Stainless steel, powder coated aluminum(which pass corrosion test)
• Type 4 from carbon steel, powder coated aluminum, and powder coated carbon steel.
• The can be manufactured from plastic and fiberglass too, which provide corrosion resistance, however, they are not that tough.

So you should match your environment with characteristics of these enclosures before invest in them.