The National Electrical Manufacturers Association (NEMA)has set the rating standards that guide the manufacturing of all electrical enclosures so as to ensure safety, proper functioning as well as compatibility of the electrical products. These ratings are responsible for providing the essential standards which are needed in defining different types of environments in which different types of electrical enclosures can be applied. NEMA ratings normally indicate specific enclosures capabilities in withstanding different environmental conditions.
NEMA ratings are specifically used in fixing enclosures and are barely used in mobile devices. All enclosures with the NEMA ratings undergo extreme stringent testing which is needed to verify if the enclosures can be secured from oil immersion, external ice, dust, water, corrosive material, etc. Each particular NEMA rating has its purpose, even though all of them are used for protecting electrical components, personnel as well as properties.
The benefits of NEMA ratings
In case you are using any type of electrical enclosure, make sure that you check its NEMA rating before you install it. It is very important that you should do so. These are the reasons:
- NEMA ratings prove that the electrical enclosures are perfectly compatible with safety as well as performance standards.
- It lets you identify which kind of enclosure is best for the environment that you want it to be installed.
- There are 600 standards that you can find in technical papers as well as application guides that will help you to have a clear understanding of electrical product function as well as products.
How enclosures are rated under NEMA
NEMA is responsible for defining as well as publishing all electrical enclosures’ standards. NEMA does not test the electrical products and it does not have any testing laboratories. The manufacturer’s compliance with NEMA is just voluntary. Some of the manufacturers just self declare their product compliance with NEMA while others opt to use third-party testing as well as certification. This enables the manufacturers to offer their clients with the tangible assurance that their products meet their expectations. Besides, NEMA offers a list of trusted testing laboratories as well as certification bodies that can help the manufacturers who are seeking for those particular services.
The most common NEMA enclosures
- NEMA Type 1 Enclosure
- These are normally used for indoor commercial applications. These include utility junctions, utility boxes, switches, etc.
- NEMA 1 enclosures normally need the lowest amount of protection. This ensures a certain degree of protection to people prohibiting them from accessing certain hazardous sections.
- Normally used for offering a certain degree of protection to the equipment which is within the enclosure against any solid contamination such as dust and dirt.
- NEMA Type 3 Enclosures
- Normally used for outdoor and indoor applications offering a certain degree of protection by preventing them access to hazardous sections.
- Rated to products that are meant to offer a certain degree of protection against any windblown dust as well as falling dirt.
- The type 3 rating indicates that the enclosure is dustproof, rainproof as well as sleet proof. Besides, it has to be able to handle the formation of ice upon the enclosure.
- NEMA Type 3R Enclosures
- All enclosures with such ratings are able to be installed in both indoor and outdoor applications. These offer a certain degree of protection to people preventing them from accessing some dangerous sections.
- They are fabricated in such a way that they are weatherproof and can withstand rain, windblown particles, snow as well as any formation of ice upon the enclosure.
- They are commonly used in meter cabinets, utility boxes, and filtered fans.
- NEMA Type 4 Enclosures
- These are commonly used in industrial applications like hydraulic controls, wiring enclosures, and operator consoles.
- They are watertight and offer protection against sleet, rain, ice formation, snow, hose directed water as well as splashing.
- The enclosures consist of a closed-loop cooling mechanism that prevents contaminants from penetrating the enclosure.
- It allows the application of air to air exchangers or air conditioners depending on the ambient temperature that surrounds them.
- NEMA Type 4X Enclosures
- These have identical features to those rated with NEMA Type 4. The only difference is that the type 4X consists of an additional feature that can withstand corrosion.
- These kinds of enclosures are normally found in marine environments, food processing plants, paper manufacturing plants, oil & gas drilling, water treatment plants, refining, and processing plants.
- Depending on the nature of ambient temperature, air to air heat exchangers and conditioners are ideal closed-up cooling systems when it comes to the NEMA Type 4X enclosures.
- NEMA Type 12 Enclosures
- Enclosures that are rated with this are designed to prevent dust prevention and are used ideal for indoor applications. It is not necessarily to be watertight even though they offer enough protection against extreme washdown conditions with extreme pressure hoses.
- It needs a closed-loop mechanism.