CPI Blog

NEMA 4 vs. NEMA 12: How Much Protection Do You Need?

June 17, 2024

When it comes to electrical or industrial 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 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,” explains Sal Perez, Regional Sales Manager at Chatsworth Products (CPI). 

“But 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.” 

 What is NEMA 12 Rating? 

  • Designed for indoor use only 
  • Material: Mild steel, foam gasket
  • Common applications: For automation control and electronic drives systems for packaging, material handling in non-corrosive environments within warehouses and manufacturing facilities. Protection against: 
    • Non pressurized light water/oil drips and splashes  
    • Non-hazardous foreign solid objects (falling dirt, dust, lint, fibers and flyings)  
    • External condensation of non-corrosive liquids 
  • No protection against significant environmental risks (rain, snow, sleet, icing and spray of liquids.) 
  • No protection against corrosive agent  

What is NEMA 4 Rating? 

  • Designed for both indoor and outdoor use
  • Material: Mild steel, foam gasket
  • Common applications: For automation electronics or telemetry for non-corrosive and non-explosive processes like telecommunications phone and cable network distribution, communications signal equipment, transportation signal controls, and security equipment.
  • Protection against: 
    • Hose down or pressurized streams of water; must provide protection against at least 65 GPM of water from a distance of no less than 10 feet for 5 minutes. 
    • Foreign solid objects (falling dirt, dust, lint, fibers and flyings.)  
    • Rain, snow, sleet (External formation of ice on the enclosure will not damage the enclosure.) 
  • No protection against corrosive agent 

What is NEMA 4X Rating? 

  • Designed for indoor or outdoor use
  • Material: Stainless steel
  • Common applications: Food and chemical processing industries, and saltwater or coastal environments.
  • Protection against: 
    • Hose down or pressurized streams of water 
    • Foreign solid objects (falling dirt, dust, lint, fibers and flyings) 
    • Rain, snow, sleet (External formation of ice on the enclosure will not damage the enclosure) 
    • Corrosive agents: salt and mild chemicals 

For more details, download our tech tip: Protect Your Sensitive Equipment at the Edge. Start by Understanding NEMA Type Ratings.

Importance of UL Rating 

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 (an industry-leading independent test laboratory), as well as the protection rating a product has. 

No matter what your applications needs may be, it is recommended to look for industrial and electrical enclosure manufacturers that have been tested by UL® to carry the Type 12, 4 or 4X listing for both the United States and Canada. 

NEMA 4 and NEMA 12 Solutions for Edge Computing and Industrial Environments 

Chatsworth Products RMR® Industrial Enclosures are engineered to protect equipment with continuous foam gasket sealing technology, certified ingress protection ratings, to support IT equipment, automation electronics and electrical controls and instrumentation in any location.  

  • Third-Party Certification: RMR Industrial Enclosures have been tested by UL to carry the  UL® Type 4 (IP66), UL Type 12 (IP55) and NEMA Type 4X protection ratings, the international standard for degrees of protection for enclosures. Certification from a third-party laboratory validates performance in accordance with standards such as NEMA 250 and IEC 60529. 

  • Unique Build-to-Order Capability: CPI is well-positioned to act as your business partner, creating custom industral enclosures so you can provide your customers with what they need, when they need it.  

  • Advanced power management and cooling accessories: RMR Industrial Enclosures offer a variety of a to address specific thermal control needs, including Filter Fans and Cooling Units. 

​For more info, check out this success story.

Cost-Effective Options for NEMA 12 Only: 

RMR® Modular Enclosure:
A flexible and cost-effective solution that a Meets NEMA Type 12 protection ratings with bolt-on panels that allow for multiple configurations to accommodate larger automation panels or racks for IT equipment. 
RMR® Swing Wall-Mount Enclosure:
Ideal for wall-mounting IT equipment; enables quick access to the front and rear of equipment through a three-part, swing-out design. Meets NEMA Type 12 protection ratings. 
RMR® Fixed Wall-Mount Enclosure:
A single access enclosure that meets NEMA Type 12 protection ratings and supports a mix of IT, electrical and electronic equipment. 

RMR Industrial Enclosure Options for NEMA 12, 4, and 4X: 

RMR® Floor-Mount Enclosures:
Provides NEMA Type 4, 4X or 12 protection for large electronic components, large automation panel applications and controls that includes floor stands for added clearance and easier cable access. 
RMR® Free-Standing Enclosures:
Provides NEMA Type 4, 4X or 12 protection for large IT, telecom or automation panel applications that supports front and rear access to deeper electrical equipment. 
RMR® Standard Wall-Mount Enclosure:
Provides NEMA Type 4 or 12 protection for smaller IT, telecom, or automation panel applications that require sturdy wall mounting. 

Quick, On-Demand Configuration 

More than 1 million configuration and personalization options are available to help you meet your unique NEMA/IP protection needs. 

To view CPI’s full industrial enclosure brochure, click here. 

Search CPI in the News
Get Blog Updates
Stay up to date on latest news and solutions.