NEMA/UL and IP ratings

From right to left: Small NEMA 12, Large NEMA 12, Large NEMA 4X

EXAIR manufactures Cabinet Coolers to keep your electrical components inside cool.  This will help to stop any costly shutdowns or premature electrical failures due to overheating.  The EXAIR Cabinet Cooler System is a simple device that generates cold air with no moving parts, condensers, or freon.  They are maintenance-free with a long-life cycle; and installation is quick and easy.  But when mounting the system to your electrical panel, you want to make sure that the Cabinet Cooler meets or exceeds the integrity standard for that environment.  There are standards that categorize electrical panels to protect workers, shield the environment, and contain the electrical components. 

Electrical panels come in all shapes, sizes and colors; and can be used in a variety of environments; indoor, outdoor, and even hazardous locations.  Depending on the place and setting, you will need to determine the minimum requirements for the integrity of your electrical panel.  For example, you do not want to use an “indoor only” electrical enclosure for outside areas.  Also, you would not want a standard enclosure to be used in a hazardous area, as it can be very dangerous.  The major organizations that create these electrical standards are NEMA, UL, and IP.  In this blog, I will cover these organizations and how they rate them.

NEMA, or National Electrical Manufacturer Association, and UL, or Underwriters Laboratory, are generally used in North America.  The difference between these two organizations is that the NEMA ratings are self-certifying while the UL requires testing by qualified inspectors, independent of the manufacturer, for compliance.  They use numbers and in some instances letters to indicate the type of environment that the enclosure can operate. EXAIR Cabinet Cooler Systems are UL listed; so, they have been tested and verified.  Currently, there are over 20 different NEMA/UL classifications.  Here is a description by WIKA that shows the different categories for both NEMA and IP.

IP, or Ingress Protection, is an international standard commonly used in Europe and is established by the International Electrotechnical Commission, or IEC.  This organization also allows for self-certification.  They use two digits to define levels of integrity for electrical enclosures against intrusion from foreign bodies and moisture. The first digit ranges from 1 to 6 which specifies the protection rating from solids.  The second digit, which ranges from 1 to 8, specifies the protection rating for ingress of water.  The higher the number, the better the protection.  The combination of these two numbers will give the protection level of the enclosure against dust and water.  There is an equivalence with the NEMA ratings to the IP ratings, but it is up to the preference of the user to verify the protection requirement. 

EXAIR offers three main NEMA types for our Cabinet Cooler Systems which are the most commonly found within facilities. We also offer an additional two types that are designated strictly for Hazardous Locations and are separately certified by UL to meet those standards.

NEMA 12

NEMA 12 (IP54) Cabinet Coolers are rated for dust tight and oil tight. NEMA 12 cabinet coolers are ideal for general industrial environments where no liquids or corrosives are present and are located inside.

NEMA 4

NEMA 4 (IP66) Cabinet Coolers are rated for dust tight, oil tight, splash resistant and indoor/outdoor service. These Cabinet Coolers incorporate a low-pressure relief valve to allow the internal hot air to escape as well as to close and seal when the cooler is not in operation.  This allows for this Cabinet Cooler to maintain the integrity of a NEMA 4 enclosure.

NEMA 4X

NEMA 4X (IP66) Cabinet Coolers offer the same protection as the NEMA 4 but are constructed of stainless steel for food service and corrosive environments.

HazLoc Cabinet Cooler Systems

HazLoc Cabinet Coolers are designed for hazardous locations and are mounted to NEMA 7, 8, and 9 enclosures.  EXAIR catalogs these Cabinet Coolers as NEMA 4 (IP66) or NEMA 4X (IP66) as mentioned above.  But their registration by UL classified is for Class I, Class II, and Class III hazardous areas.  The reason that they do not match the NEMA rating of the hazardous panels is because they require an X-type or Z-type purge system.  In combination, they will not sacrifice the integrity of hazardous electrical panels. 

EXAIR has Cabinet Coolers in stock with a variety of cooling capacities from 275 BTU/hr to 5,600 BTU/hr (69 Kcal/hr to 1,411 Kcal/hr).  We also offer them in 316SS, high temperature versions, and non-hazardous purge.  We do have a Cabinet Cooler System Calculator to help determine the best product for your application.  If you have any additional questions, an Application Engineer at EXAIR can assist you.   

John Ball
Application Engineer
Email: johnball@exair.com
Twitter: @EXAIR_jb

EXAIR’s New Cabinet Cooler® System Calculator

For the longest time we have been using this form on EXAIR.com to get the information we needed to manually calculate the internal and external heat loads and ultimately make a recommendation on which Cabinet Cooler System would be best for that application! Typically it would take thirty minuets to an hour to get a email back from a application Engineer!

While the manual Cabinet Cooler Sizing Guide worked great (and we will still reply within 24 hours), we have been racking our heads over here to better that process and get you a solution faster than ever! Now you type in your information and you have a recommendation and a link to that product on the website where you can learn more or place an order! So you can go from form to order in less than 5 Minuets!!!! Check it Out HERE!!

By providing certain information like size of the enclosure, NEMA rating needed, and environmental conditions, this new calculator will sort through our large selection of ready-to-ship Cabinet Cooler® Systems and provide instant feedback on the best model number for any applicable electrical enclosure.  Taking the guess work out of the equation, EXAIR’s Calculator ensures the customer that they can be confident in selecting the correct product for their unique specifications. You can even Print the form for your records!

Cabinet Cooler Calculator

            EXAIR’s complete line of Cabinet Cooler systems include 120V AC, 240V AC and 24V DC thermostat voltage, continuous operation, type 316 stainless steel and high temperature models – all of which are selectable with the new calculator. Find this new tool on the website EXAIR.com, in the Knowledge Base Calculators, along with many other resources, such as the CAD Library and Application Database, which also help customers choose a perfect solution. Cabinet Cooler systems start at $534. https://www.exair.com/knowledgebase/calculator-library/cabinet-cooler-system-calculator.html

Jordan Shouse
Application Engineer

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The Basics of Calculating Heat Load for Cooling Electrical Cabinets

Is your electrical cabinet overheating and causing expensive shut downs? As spring and summer approach, did your enclosures have seasonal overheating problems last year? Is your electrical cabinets AC Unit failing and breaking down? Then it may be time to consider EXAIR Cabinet Coolers Systems. These systems are compressed air powered cooling units designed to keep your cabinet cool in hot environments. Major benefits include no moving parts to wear out, UL listed to maintain the NEMA integrity of your enclosure (also CE compliant), they are simple and quick to install and they reliably turn on and off as needed (perfect for solving seasonal overheating).

Just one question then; how do you pick which Cabinet Cooler is best for your application? It’s time to bust out ye ole trusty calculator and crunch some numbers. Keep in mind that the following calculations use baselines of an Inlet air pressure of 100 psig (6.9 bar), compressed air temperature of 70F (22C), and a desired internal temp of 95F (35C). Changes in these values will change the outcome, but rest assured a Cabinet Cooler system will generally operate just fine with changes to these baselines.

How the EXAIR Cabinet Cooler System Works


Before we dig right into the math, keep in mind you can submit the following parameters to EXAIR and we will do the math for you. You can use our online Cabinet Cooler Sizing Guide and receive a recommendation within 24 hours.

There are two areas where we want to find the amount of heat that is being generated in the environment; this would be the internal heat and the external heat. First, calculate the square feet exposed to the air while ignoring the top. This is just a simple surface are calculation that ignores one side.

(Height x Width x 2) + (Height x Depth x 2) + (Depth x Width) = Surface Area Exposed

Next, determine the maximum temperature differential between the maximum surrounding temperature (max external temp) and the desired Internal temperature. Majority of cases the industrial standard for optimal operation of electronics will work, this value is 95F (35C).


Max External Temp – Max Internal Temp Desired = Delta T of External Temp

Now that we have the difference between how hot the outside can get and the max, we want the inside to be, we can look at the Temperature Conversion Table which is below and also provided in EXAIR’s Cabinet Cooler System catalog section for you. If your Temperature Differential falls between two values on the table simply plug the values into the interpolation formula.

Once you have the conversion factor for either Btu/hr/ft2, multiply the Surface Area Exposed by the conversion factor to get the amount of heat being generated for the max external temperature. Keep this value as it will be used later.

Surface Area Exposed x Conversion Factor = External Heat Load

Now we will be looking at the heat generated by the internal components. If you already know the entire Watts lost for the internal components simply take the total sum and multiply by the conversion factor to get the heat generated. This conversion factor will be 3.41 which converts Watts to Btu/hr. If you do not know your watts lost simply use the current external temperature and the current internal temperature to find out. Calculating the Internal Heat Load is the same process as calculating your External Heat Load just using different numbers. Don’t forget if the value for your Delta T does not fall on the Temperature conversion chart use simple Interpolation.

Current Internal Temp – Current External Temp = Delta T of Internal Temperature
Surface Area Exposed x Conversion Factor = Internal Heat Load

Having determined both the Internal Heat Load and the External Heat Load simply add them together to get your Total Heat Load. At This point if fans are present or solar loading is present add in those cooling and heating values as well. Now, with the Total Heat Load match the value to the closet cooling capacity in the NEMA rating and kit that you want. If the external temperature is between 125F to 200F you will be looking at our High Temperature models denoted by an “HT” at the start of the part number.

From right to left: Small NEMA 12, Large NEMA 12, Large NEMA 4X

If you have any questions about compressed air systems or want more information on any of EXAIR’s products, give us a call, we have a team of Application Engineers ready to answer your questions and recommend a solution for your applications.

Cody Biehle
Application Engineer
EXAIR Corporation
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Cabinet Cooler NEMA Ratings Explained

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Temperatures are heating up across the US, when this happens it can wreak havoc on the sensitive electronics in your facility.  If you’re a follower of the EXAIR Blog, you’ve noticed that we’ve spent a great deal of time recently discussing the Cabinet Coolers. From a description of how they work, specific applications, as well as how to determine what size you’ll need, we’ve covered quite a range of topics. Equally important, though, is the NEMA rating of the Cabinet Cooler. I’d like to take a moment to discuss the different NEMA ratings for the Cabinet Coolers that EXAIR has to offer and where each should fit.

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EXAIR’s Model 4008 Nema 12 Cabinet Cooler

NEMA 12 – The NEMA 12 rating is for enclosures that are indoor and provide a degree of protection to personnel against access to hazardous parts as well as prevent any materials from entering the enclosure such as dust, debris, or moisture from light splashing. This standard duty style of Cabinet Cooler is best served indoors on the shop floor where there aren’t any wash-down areas or excessive moisture.

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Model 4880-ETC120

NEMA 4 – A NEMA 4 rated cabinet cooler is designed for either indoor or outdoor use. It, too, provides protection to personnel against access to hazardous parts and prevents dust, dirt, or debris from entering the cabinet. In addition to providing the same levels of protection as the NEMA 12, the NEMA 4 rating also means that the equipment will be protected from water such as rain, sleet, snow, splashing water, and even hose directed water.

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Model 4880SS-316

NEMA 4X – The NEMA 4X carries the same levels of protection as the NEMA 4, but also adds an additional level of protection against corrosion. EXAIR’s NEMA 4X Cabinet Coolers are constructed of either 303 or 316 Stainless Steel.

EXAIR’s Cabinet Coolers are available from stock with cooling capacities ranging from 550 Btu/hr – 5,600 Btu/hr. With a variety of different materials and NEMA ratings, EXAIR has the right Cabinet Cooler ready to ship today to prevent your sensitive electronics from shutting down. Don’t let yourself get frustrated dealing with heat-related issues, get a maintenance-free Cabinet Cooler installed ASAP! Fill out the Cabinet Cooling Sizing Guide and an Application Engineer will be in touch with you within 24 hours with a quote for the most suitable model.

Tyler Daniel
Application Engineer
E-mail: TylerDaniel@EXAIR.com
Twitter: @EXAIR_TD