To ensure safety and functionality, electrical equipment and electronic components are usually subject to both mandatory and voluntary industry standards. Keeping these components and circuits protected from environmental dust, moisture, and contaminants is important for both indoor and outdoor use. Specialized electrical enclosures protect electrical systems housed inside them, and they also keep workers and other people safe.
Depending on the details of an application or setting, the National Electrical Manufacturers Association (NEMA) has developed a set of standards for electrical enclosures for different uses. Hope Electrical Products manufactures NEMA-rated enclosures that meet these safety and design standards. Here, we’ll provide some background on NEMA ratings and look at what they specify.
What Is a NEMA Rating?
As an organization, NEMA develops industry standards for electrical goods manufacturing. Ratings are voluntary and revised every five years. They are largely focused on enclosures that house electronics and electrical equipment
While not strictly mandatory, NEMA-rated enclosures are considered safe and trustworthy, especially in challenging operating conditions. Custom enclosures that meet NEMA rating guidelines are an excellent way to communicate the quality and safety of your products.
Types of NEMA Enclosure Ratings
NEMA ratings are a set of guidelines for the design and manufacture of electrical enclosures that will be used in different settings. All rating levels are designed to protect personnel and others from electrical hazards and to prevent unauthorized access to the contents.
Beyond that, depending on the application, ratings indicate suitability for:
- Indoor or outdoor use (sometimes both)
- Hazardous and non-hazardous environments
- Resistance to water ingress, direct spray, or submersion
- Dirt, dust, and debris protection
- Ice protection
- Explosion-proofing
- Corrosion resistance
- Protection from oils and coolants
There are several NEMA enclosure ratings. To ensure safety and equipment performance, select the rating that most closely matches the needs of your application.
NEMA 1
These are rated for indoor use and provide some protection from unauthorized access. They also protect the contents from falling dirt or debris and are dust-tight.
NEMA 3
These do not allow falling rain, sleet, snow, or windblown dust to get inside the enclosure. Rain resistance is rated up to 5 psi from +/- 45° from vertical. They are rated for indoor or outdoor use, and do not allow ice to form in the enclosure.
NEMA 3R
NEMA 3R-rated enclosures are very similar to NEMA 3-rated enclosures. The primary difference is they do not protect against windblown dust. NEMA 3R enclosures also include drainage holes to allow any accumulated water to escape.
NEMA 3RX
NEMA 3RX-rated enclosures meet the same requirements as NEMA 3R enclosures with a higher level of corrosion resistance. These are suitable for use in saltwater or marine environments.
NEMA 4
NEMA 4-rated enclosures can be used in indoor or outdoor applications and are similar to NEMA 3-rated enclosures. The primary difference is added protection against directed water from a hose or from general water ingress. The enclosure is rated to withstand 65 gallons per minute in a one-inch stream.
NEMA 4X
Like a NEMA 4-rated enclosure, a 4X enclosure can be used indoors or outdoors and resists rain, snow, ice, and dirt. They also have greater corrosion resistance.
NEMA 6
NEMA 6-rated enclosures can be used indoors or outdoors and are designed to resist ingress of liquids due to occasional, temporary submersion to a limited depth.
NEMA 6P
A NEMA 6P-rated enclosure is similar to a NEMA 6 enclosure and can resist ingress of liquids from occasional prolonged submersion to a limited depth.
NEMA 7
NEMA 7-rated enclosures are explosion-proof and are designated for use indoors in hazardous locations with Class 1, Division 1, Group A, B, C, or D environments (these are acetylene, hydroben, ethylene, and propane/methane, respectively), according to National Fire Protection Association (NFPA) 70 Code.
NEMA 12
NEMA 12-rated enclosures are general-purpose enclosures for interior use. They protect against dripping or splashing water, unauthorized access, dust, and dirt. These enclosures also do not include knockouts for cables, cords, antennas, and other components.
Custom NEMA Enclosures at Hope Electrical Products
Well-designed electrical enclosures keep electrical systems secure and free from the elements, environmental hazards, and damage. At Hope Electrical Products, we manufacture custom NEMA-rated enclosures to meet your requirements for safety and protection, including NEMA 4, NEMA 4X, and NEMA 6P enclosures and more.
Contact our team of experts to learn more about our electrical enclosures and get started on finding the right solution for your needs.