What Are NEMA Types And Why Do They Matter for Your Enclosure?

NEMA Type 4X Dual Cabinet Cooler System in 316 Stainless Steel

Electrical enclosures and control cabinets come in all shapes, sizes and colors. They all have the same job, to protect and house critical electronics in order to ensure a machine or piece of equipment can safely operate.  These electronics and enclosures are also located in a variety of environments that differ just as much as the panels themselves.  With that, different requirements and needs to protect the internal components of the cabinet are needed.  A systematic approach to designate the requirements for these panels to meet the needs of different environments was designated by the National Electrical Manufacturers Association.  Thus, the NEMA rating was created.

Currently, there are nearly 20 different NEMA classifications that enclosures can be designed for and operate within. EXAIR offers three main NEMA types which are the most commonly found within industrial facilities as well as an additional two that are designated strictly for Hazardous Locations and are separately certified by UL to meet those standards.

NEMA Type 12 Cabinet Cooler System protects an HMI on a machine tool.

NEMA Type 12 enclosures are constructed mainly to be used indoors and to protect personnel in the area from any hazardous equipment such as electrical contacts or transformers. This also helps to protect those electronics from things like foreign matter in the air around the panel and keep any kind of drips of moisture from getting into the electronics. These are found in most general light assembly or industrial environments.

EXAIR NEMA Type 4 Cabinet Cooler System protects against direct water.

NEMA Type 4 enclosures are a few steps up from NEMA Type 12 in the level of protection they give the internal electronics. These are suitable for indoor or outdoor use to protect both personnel and the internal cabinet components from the environment.  They are dust and airtight as well as protect from the ingress of water and ice. These can be found in washdown environments, hot environments, or extremely dirty environments throughout industry.

EXAIR NEMA 4X Cabinet Cooler Systems are made of corrosion-resistant stainless steel for corrosive environments and are also available with Side Mount Kits.

NEMA Type 4X enclosures are similar to NEMA Type 4 as far as that they protect for and the environments they are suited for, the standard also adds a level of corrosion resistance to the panels which permit them for use around certain chemicals and/or outdoors in certain facility environments.

Hazardous Location Cabinet Cooler Systems

The last type to be discussed is the Hazardous Locations that are offered in both NEMA Type 4 and NEMA Type 4X ratings.  These environments are under strict classifications and EXAIR follows the UL Classified certifications for these restricted areas.

If the panel or environment within a given facility is in a different NEMA type than the ones mentioned above it can often be remedied by going to the next highest level.  For instance, NEMA Type 5 rated enclosures could be protected by a NEMA Type 4 and still maintain their integrity.

If you would like to discuss NEMA ratings or what type of panel may be within your facility, please contact us.

Brian Farno
Application Engineer
BrianFarno@EXAIR.com
@EXAIR_BF

EXAIR Cabinet Cooler Systems – How Do they Work?

Cabinet Cooler systems eliminate heat related problems by providing a temperature controlled environment inside of electrical enclosures. Typically set to maintain 95F (but also adjustable) a Cabinet Cooler system can withstand harsh, remote environments with little maintenance. They cool heat loads up to 5600 Btu/Hr and are UL listed to maintain your cabinet’s NEMA integrity. 

Compressed air enters the vortex tube powered Cabinet Cooler and is converted into two streams, one hot and one cold. Hot air from the vortex tube is muffled and exhausted through the vortex tube exhaust. The cold air is discharged into the cabinet through the included cold air distribution kit. The displaced hot air in the cabinet rises and exhausts to atmosphere through the cabinet cooler body. The control cabinet is both cooled and purged with cool, clean air. Outside air is never able to enter the control panel.

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How it works! 

EXAIR’s compressed air operated, Cabinet Cooler Systems are a low cost, reliable way to cool and purge electronic control panels. There are no moving parts to wear out and no filters to replace, eliminating the need for constant monitoring.

NEMA Type 12 (IP54) and NEMA 4 and 4X (IP66) models are available that are very compact and mount in just minutes through an ordinary electrical knockout.

Cabinet Cooler Family
EXAIR Cabinet Cooler Sizes 

Available in a wide range of cooling capacities, ranging from 275 Btu/hr. for our smallest system, up to 5,600 Btu/hr. for our largest Dual System.

Thermostat control systems are the most efficient way to operate a Cabinet Cooler as they limit compressed air use by operating only when the temperature inside the enclosure approaches critical levels. Continuous Operating Systems are recommend when constant cooling and constant positive pressure inside the panel is required.

Thermostat controlled Cabinet Cooler Systems are the best option when experiencing fluctuating heat loads caused by environment or seasonal changes. Thermostatically Controlled Systems include a Cabinet Cooler, adjustable thermostat, solenoid valve, cold air distribution kit consisting of tubing and self adhesive clips to duct the cold air inside the panel and a filter separator to remove any water or contaminants from the supply.

Thermostat and ETC

If you would like to discuss our cabinet cooler systems or any of EXAIR’s engineered solutions, I would enjoy hearing from you…give me a call.

Jordan Shouse
Application Engineer
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Cabinet Cooling with Thermostat Control and ETC

An EXAIR Cabinet Cooler® System with either the Thermostat Control or the Electronic Temperature Control (ETC) option includes a temperature measuring device that is used to control the operation of the Cabinet Cooler System to maintain the set-point temperature.Thermostat and ETC

For most industrial enclosure cooling applications, a temperature of 95°F (35°C) is sufficient to be below the rated maximum operating temperature of the electrical components inside the cabinet. EXAIR Thermostats are preset to 95°F (35°C) and are adjustable. Maintaining the cabinet at 95°F (35°C) will keep the electronics cool and provide long life and reduced failures due to excessive heat. But if 95°F (35°C) is good, why not cool the cabinet to 70°F (21.1°C)?

When cooling an enclosure to a lower temperature, two things come into play that need to be considered. First, the amount of external heat load (the heat load caused by the environment) is increased. Using the table below, we can see the effect of cooling a cabinet to the lower temperature. For a 48″ x 36″ x 18″ cabinet, the surface area is 45 ft² (4.18 m²). If the ambient temperature is 105°F (40.55°C), we can find from the table the factors of 3.3 BTU/hr/ft² and 13.8 BTU/hr/ft² for the Temperature Differentials of 10°F (5.55°C) and 35°F (19.45°C). The factor is multiplied by the cabinet surface area to get the external heat load. The heat load values calculate to be 148.5 BTU/hr and 621 BTU/hr, a difference of 472.5 BTU/hr (119.1 kcal/hr)

External Heat Load

The extra external heat load of 472.5 BTU/hr (119.1 kcal/hr) will require the Cabinet Cooler System to run more often and for a longer duration to effectively remove the additional heat. This will increase, unnecessarily, the operating costs of the cooling operation.

The other factor that must be considered when cooling an enclosure to a lower temperature is that the Cabinet Cooler cooling capacity rating is effected. I won’t go into the detail in this blog, but note that a 1,000 BTU/hr Cabinet Cooler (rated for 95°F (35°C cooling) working to cool a cabinet down to 70°F (21.1°C) instead of 95°, has a reduced cooling capacity of 695 BTU/hr (174 kcal/hr).  The reduction is due to the cold air being able to absorb less heat as the air rises in temperature to 70°F instead of 95°F.

In summary – operating a Cabinet Cooler System at 95°F (35°C) provides a level cooling that will keep sensitive electronics cool and trouble-free, while using the least amount of compressed air possible.  Cooling to below this level will result in higher operation costs.

If you have questions about Cabinet Cooler Systems or any of the 15 different EXAIR Intelligent Compressed Air® Product lines, feel free to contact EXAIR and myself or any of our Application Engineers can help you determine the best solution.

Brian Bergmann
Application Engineer
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Special Cabinet Cooler Options – High Temperature, Non-Hazardous Purge and Type 316 Stainless Steel

Recent blog discussions about the EXAIR Cabinet Cooler Systems have covered many topics including correctly sizing one, the NEMA ratings, and how-they-work.  In this blog I will review three special options that are available for the most extreme environmental conditions- high temperatures, dirty environments, and harsh or corrosive areas.

High Temperature – For enclosures that reside in high temperature ambient conditions such as near furnaces, boilers, or ovens, EXAIR offers a High Temp version, with special internal components designed to withstand the elevated temperatures.  Cabinets near sources of high heat certainly need to be kept cool, and the EXAIR High Temperature Cabinet Cooler is specially suited to for use in these locations.

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High Temperature Dual Cabinet Cooler System

Non-Hazardous Purge (NHP) – Cabinet Cooler Systems with this feature provide a continuous positive purge within the enclosure to prevent contaminants from entering through small holes or conduits.  Especially suited for dirty and dusty environments, the NHP Cabinet Cooler Systems provide a slight positive pressure inside the enclosure. This is done by passing 1 SCFM (28 SLPM) of air through the cooler when the the solenoid is in the closed position. When the thermostat reaches the set-point temperature and energizes the solenoid, the full line pressure of air is delivered to the Cabinet Cooler providing the full cooling capability, and still keeping the positive pressure.  When the internal temperature cools to the set-point, the solenoid closes and the system returns to the 1 SCFM (28 SLPM) of air flow condition.

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Non-Hazardous Purge Cabinet Cooler for Dirty, Dusty Environments

Type 316 Stainless Steel NEMA 4X Cabinet Coolers – For enclosures that are in food service, pharmaceutical, harsh, and/or corrosive environments, and any application where 316 stainless steel is preferred, the Cabinet Coolers are available in the Type 316 stainless material. The systems are UL Listed for wash down environments, ensuring the enclosure electrical contents remain cool and dry under any condition. Noted applications include on ocean going ships, power plants, medical device manufacturing facilities, and bakeries.

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Type 316 Stainless Steel NEMA 4X Cabinet Cooler System

Please note that the High Temperature, Non-Hazardous Purge and Type 316 Stainless Steel Cabinet Coolers are each available from stock!  No waiting for these special models.

To discuss your application and how a Cabinet Cooler System or any EXAIR Intelligent Compressed Air Product can improve your process, feel free to contact EXAIR, myself, or one of our other Application Engineers. We can help you determine the best solution!

Brian Bergmann
Application Engineer

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