When it comes to electrical enclosures, knowing where it will be used and the level of protection required are two important considerations.
The National Electrical Manufacturer Association (NEMA) has established a scale from 1 to 13 to help identify which type of enclosure will best protect the enclosure and equipment inside.
However, selecting an enclosure with the wrong rating is one of the most common errors when specifying a NEMA enclosure. This can result in inadequate protection for equipment, leading to wasted time and money.
Two of the most commonly confused ratings are NEMA 4 and NEMA 12. Many customers assume they need NEMA 4 which has one of the highest levels of enclosure protection. However, the protection rating is so high that it may exceed the needs of the customer, resulting in unnecessary cost.
“If you're planning to support systems and technology equipment in an outdoor environment where you expect a downpour of water at any given time, or if it's directly exposed to the sunlight, then it’s recommended to deploy a NEMA Type 4 enclosure. If you plan on supporting equipment in a covered parking structure, dusty or dirty environment, or even a hot warehouse where minimal water is present, such as light splashing, then you can lead with a NEMA Type 12 enclosure,” Explains Sal Perez, Regional Sales Person for Chatsworth Products (CPI).
- NEMA 4
- Common applications: Used to house standard IT networking connections and equipment, automation electronics or telemetry for non-corrosive and non-explosive processes like transportation signal controls, telecommunications phone and cable network distribution, communications signal equipment, and security equipment
- Designed for both indoor and outdoor use
- Used in applications where hosedown or pressurized streams of water occurs
- Must provide protection against at least 65 GPM of water from a distance not less than 10 feet for 5 minutes
- Protects against foreign solid objects (falling dirt, dust, lint, fibers and flyings)
- External formation of ice on the enclosure will not damage the enclosure
- Protects against rain, snow, sleet
- Mechanism may not be operable when the enclosure is ice-covered
- No protection against corrosive agents
- NEMA 12
- Common application: automation control and electronic drives systems, including packaging, material handling, non-corrosive process control, and manufacturing
- Designed for indoor use
- Used in applications where non-pressurized oil and water occurs (light drips and splashes)
- Protects against non-hazardous foreign solid objects besides water
- No protection against significant environmental risks (rain, snow, sleet, icing and spray of liquids)
- No protection against corrosive agents
CPI's RMR Industrial Enclosures have been tested by UL, an industry-leading independent test laboratory, to carry the UL Type 12 listing and UL Type 12 listing for Canada. RMR Enclosures also carry UL classification to comply with IP55 per ANSI/IEC 60529, the international standard for degrees of protection for enclosures. Because both NEMA and IP standards are voluntary, meaning that any manufacturer can claim to have NEMA- or IP-rated products, it is important to check for a third-party tested UL Listing certification as well as the protection rating a product has.
To learn more about CPI’s industrial enclosures, click here.
Shannon Ryan, Digital Content Specialist