Georges J. Ranque is known as the inventor and father of the Ranque-Hilsch Vortex tube. The vortex tube is device that takes a compressed gas and generates hot and cold streams from a source of compressed gas. George accidentally discovered the phenomenon on accident while studying physics at Ecole Polytechnique in Paris France. Ranque was looking was performing an experiment on a vortex-based pump to vacuum up iron fittings; during the experiment he noticed that warm air was being expelled out of one side and cold air out of the other when he inserted a cone into one end of the vortex. In 1931 Ranque filed for a patent for the vortex tube and two years later presented a paper on it.
Georges vortex tube was all but lost and forgot about until 1945 when the German physicist Rudolph Hilsch published a paper on the device. This paper became widely read and exposed the vortex tube to the industrial manufacturing environment. This paper revived what was thought to be lost and led the vortex tube into what we see today.
During World War 2 Georges Ranque started to develop different steels that would be used in military aviation efforts. He later went on to work at Aubert et Duval Steelworks as the Director of Metallurgical Laboratory. While at Duval he would continue to developing alloys for the aviation industry.
Interestingly, in 1972 he went on to publish a book on the search for the Philosophers Stone, a mythological chemical substance that Alchemist’s thought could be used to turn base metals into Gold. The following year in 1973 he passed away in his home just outside of Paris.
Here at EXAIR we have expanded the uses of Ranque’s original vortex tubes for various different cooling uses. The vortex tube can be found in our Cold Guns, Spot Coolers, and Cabinet Coolers. In many cases EXAIR’s spot coolers and cold guns have been used to replace coolant in simple milling and grinding applications. Also, EXAIR’s Cabinet Coolers have been keeping control cabinets from overheating for many decades.
If you have any questions or want more information on how we use our vortex tubes to improve processes all over industry. 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 Visit us on the Web Follow me on Twitter Like us on Facebook
Heat can cause real problems for electrical and electronic components, in a hurry…we all know that. Fortunately, we can also specify the right Cabinet Cooler System for you in a hurry too. And since we keep them all in stock, we can get it to you in a hurry as well.
You can access our Cabinet Cooler Sizing Guide online, here. You can fill in the blanks and submit it, or you can call in your data. We do it over the phone all the time, and it only takes a minute. Here’s what we’re going to ask for, and why:
Enclosure dimensions. We need the length, width, and height of your enclosure to calculate the heat transfer surface, and the volume of the enclosure.
Current Internal Air Temperature. How hot is it inside your enclosure? This is the starting point for figuring out the internal heat load…how much heat the components inside the box is generating. This needs to be the air temperature – don’t use a heat gun, or you’re going to give me the surface temperature of something that may or may not be close to what I need. Just put a thermometer in there for a few minutes.
Current External Air Temperature. How hot is it in the area where the enclosure is located? We’re going to compare this to the internal air temperature…the difference between the two is actually proportional to the heat load. Also, if there’s anything cooling the enclosure right now (like circulating fans; more on those in a minute,) this reading is key to figuring out how much heat they’re removing.
Maximum External Air Temperature. How hot does it get in the area on, say, the hottest day of summer? We’ll need this to calculate the external heat load…how much heat the enclosure picks up from its surroundings.
Maximum Internal Temperature Desired. Most electrical and electronic component manufacturers publish a maximum operating temperature of 104F (40C) – it’s kind of an “industry standard.” Based on this, a lot of us in the enclosure cooling business set our products’ thermostats to 95F (35C) – if we’re maintaining the air temperature a decent amount cooler than the components are allowed to get, history and practice has shown that we’re going to provide more than adequate protection. If your enclosure houses something with more sensitive temperature limitations, though, we can work with that too…that’s the only time you’re going to want to put something other than 95F (35C) in this field.
Cabinet Rating. This is all about the environment…we offer three levels of protection, per NEMA standards:
The NEMA rating does not affect the cooling capacity at all.
Other: If the enclosure is mounted to the side of a machine, or a wall in the plant, you really don’t need to put anything here. If it’s outside and exposed to direct sunlight, tell us what the surface finish (i.e., polished metal, painted grey, etc.) is so that we can account for solar loading too. If anything else is unusual or peculiar about the application, let us know that too.
My Cabinet Is…Not Vented, Vented, Wall Mounted, Free Standing, Fan(s). We’ll use what you tell us here to verify heat transfer surface (a wall mounted cabinet’s back surface isn’t a radiating surface, for example.) Also, I mentioned fan cooling before, so without further ado…
Fan diameter or SCFM. If there are fans circulating air into (and/or out of) the enclosure, they’re providing a finite amount of cooling right now. Proper installation of a Cabinet Cooler System is going to require their removal. Running a Cabinet Cooler System on a vented enclosure is just like running your air conditioner with the windows open. So, if we know the size (or the SCFM…sometimes there’s a label on those fans, and we LOVE those folks who do that) then we can use that, and the temperatures you gave us above, to take the fan cooling into account.
Once we have all this information, it’s down to the math. Like I said, we do this all the time (especially during “Cabinet Cooler Season”) – give me a call. Your heat problem isn’t waiting; why should you?
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.
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.
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.
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.
During a recent visit with our distributor in Lima, Peru I had the pleasure of visiting a beverage manufacturing facility to discuss EXAIR’s Cabinet Coolers. They have several panels throughout the facility with A/C units installed. A lack of adherence to scheduled maintenance was causing the filters to clog and restrict the cooling power of the A/C unit. Due to staffing issues, their maintenance department was very thin and regular maintenance items were getting missed.
When the filters would clog, the panels would overheat and stop production. Their solution was to open the panel up and blow fans on them, forcing even more dust into the enclosure. In their search for an alternative solution, they came across EXAIR’s Cabinet Cooler Systems and reached out to our distributor. The A/C unit that was installed on the panel had a capacity of 800W (2,728 Btu/hr). EXAIR offers a 2,800 Btu/hr system from stock that matched up perfectly for them.
They installed a Model 4340-24VDC Nema 12 Cabinet Cooler System with 24VDC thermostat control and removed the A/C system. With no moving parts and no refrigerants, there’s absolutely no maintenance required. Just set it and forget it! The Cabinet Cooler has kept the electronics inside at 95°F, preventing any potential for heat related shut downs. Since all Cabinet Coolers must be installed onto a sealed enclosure, there is no need for filters on the enclosure to prevent dirty ambient air from entering. They’re now working to replace each of the A/C units in the facility with an EXAIR Cabinet Cooler.
EXAIR manufactures Cabinet Coolers for any industrial environment. Cabinet Coolers maintain Nema 4, Nema 4X, and Nema 12 integrity on the enclosure and are also UL Listed and CE Compliant. For applications that may be in a classified area, the Hazardous Location Cabinet Cooler has been approved by UL for use in Class 1 Div 1 – Groups A, B, C, and D; Class II Div 1 – Groups E, F, and G; and in Class III areas. Cooling capacities as high as 5,600 Btu/hr can be achieved with one of our Dual Cabinet Cooler Systems.
Stop wasting precious time maintaining you’re A/C systems, or dealing with heat related shutdowns and get a Cabinet Cooler on order today. Fill out the sizing guide online, and one of our Application Engineers will be in touch to provide you with the most suitable model for your application. Act fast, the current Cabinet Cooler promotion expires at the end of August!
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. So, it is important to turn the cabinet cooler system on to keep the components cool, but at the same time we all know compressed air can be expensive if you over use it. A thermostat allows you to turn the cooler off when the enclosure is at or below the desired temperature, saving compressed air over continuous operation.
Here at EXAIR we are all about Engineered Solutions that will not only save you money but help your company “Go Green” by drastically lowering your energy costs. And when it comes to Cabinet Coolers, we have several options to control and manage the compressed air supply.
The most popular option is our Thermostat Control. EXAIR thermostats feature a bimetallic contact strip to open and close the electrical circuit in response to air temperatures. These thermostats quickly respond to changes in air temperature and are specifically suited for their intended use. Preset for 95°F (35°C), a suitable temperature for most electronic devices, these thermostats are fully adjustable for specific application needs. When thermostat closes it then turns the solenoid valve off turning the compressed air supply off. These thermostats are available in 12VAC, 240VAC and 24VDC.
In the event a more sophisticated thermostat control is needed, Electronic Temperature Control units can be implemented. These standalone units utilize a thermocouple to determine internal cabinet temperatures which display onto a digital readout. Push-button controls on the digital readout board allow for easy modification of the internal cabinet temperature set-point. When the desired internal temperature is reached, the Cabinet Cooler system will turn off automatically.
One accessory that will give the flexibility to install EXAIRS cabinet cooler system is our Side Mount Kit. Sometimes there isn’t room above an electrical panel to fit the Cabinet Cooler, even though it takes just 5″ to 7.25″ of space above. In these cases, the Side Mount Kit is available to handle any of the Cabinet Cooler sizes and NEMA ratings. The NEMA 4 and 4X Cabinet Coolers must be mounted vertically for the unit to properly resist the ingress of liquids and maintain the integrity of the cabinet NEMA rating.
The Side Mount Kits install into a standard electrical knockout (1-1/2 NPS) for easy installation.
If you’re in need of a suitable cooling solution for an industrial enclosure, consider an EXAIR Cabinet Cooler systems. They’re smaller than traditional AC units, faster to install, and require little-to-no-maintenance. Feel free to contact an EXAIR Application Engineer with any questions, or fill out our online Cabinet Cooler Sizing Guide to have an Application Engineer contact you.
At EXAIR we’ve been providing enclosure cooling solutions for decades, and in many cases those cooling solutions have remained in place for decades as well. In the time we’ve been in the market with industrial enclosure cooling solutions we’ve encountered a number of alternative means for enclosure cooling. One of those methods is an air-to-air heat exchanger.
An air-to-air heat exchanger uses the temperature differential between the ambient air surrounding an enclosure and the hot air inside an enclosure to create a cooling effect. A closed loop system exchanges the heat inside the enclosure with the outside air in an effort to maintain a set internal temperature. The heat exchange of most air-to-air unit relies on a heat pipe, a heat-transfer device which converts an internal refrigerant liquid into vapor by placing one end of the pipe in contact with the hot environment. The heated vapor travels to the other end of the pipe which is in contact with a cooler environment. The vapor condenses back into a liquid (releasing latent heat) and returning to the hot end of the pipe and the cycle repeats.
But, this type of a solution does give some cause for concern, especially when considering their use in an industrial environment. Here are the key points to keep in mind when comparing an air-to-air cooler to an EXAIR Cabinet Cooler.
Required temperature differential based on ambient air temp
An air-to-air heat exchange relies on the ΔT between the ambient air temperature and the internal enclosure air temperature to produce cooling. If this ΔT is low, or the ambient temperature rises, cooling is diminished. This means that as the temperatures in your facility begin to rise, air-to-air heat exchangers become less and less effective. Larger air-to-air heat exchangers can be used, but these may be even larger than the enclosure itself.
EXAIR Cabinet Coolers rely on the ΔT between the cold air temperature from the Cabinet Cooler (normally ~20°F) and the desired internal enclosure temperature (normally 95°F). The cold air temperature from the Cabinet Cooler is unaffected by increases in ambient temperatures. The large ΔT and high volume cold air flow produced by a Cabinet Cooler results in more cooling capacity. And, we can increase cooling capacity from a Cabinet Cooler without increasing its physical footprint, which is already much, much smaller than an air-to-air type of unit.
Cooling in high temperature environments
Due to their nature of operation, an air-to-air heat exchanger must have an ambient temperature which is lower than the desired internal temperature of the enclosure. If the ambient air has a higher temperature, air-to-air units provide zero cooling.
Cabinet Coolers, on the other hand, can be used in hot, high temperature environments up to 200°F (93°C).
Cooling in dirty environments
Dirt in the ambient environment will impact cooling performance with an air-to-air heat exchanger. In order for the air-to-air unit to effectively remove heat, the heat pipe must have access to ambient air. With any exposure to the ambient environment comes the possibility for the ambient end of the heat pipe to become covered in ambient contaminants such as dust. This dust will create an insulation barrier between the heat pipe and the ambient air, decreasing the ability for the heat pipe to condense the vapors within. Because of this, most air-to-air devices use filters to separate the heat pipe from the ambient environment. But, when these filters become clogged, access to ambient temperatures are reduced, and cooling capacity of the air-to-air unit reduces as well.
Cabinet Coolers have no problem operating in dirty environments. In fact, it is one of their strengths. Without any moving parts to wear out or any need to contact ambient air for cooling purposes, a dirty environment poses no problems. In fact, check out this blog post (and this one) about EXAIR Cabinet Coolers operating maintenance free for years in dirty environments.
Size and time required to install
Air-to-air heat exchangers vary in size, but even the smallest units can have large dimensions. Many applications have limited space on the enclosure, and a large, bulky solution can be prohibitive. Couple this with the time and modification required to the enclosure to install a large air-to-air unit, and the “solution” may end up bringing additional problems.
Another key aspect of the Cabinet Cooler is its size. Small, compact, and easy to mount on the top or side of an enclosure, Cabinet Coolers install in minutes to remove overheating problems.
Heat within an electrical cabinet can be a major issue for manufacturing companies. The costs associated with down time and repairs on sensitive electronics that fail due to heat or environmental contaminants, are an unnecessary burden. If you have any questions about how an EXAIR Cabinet Cooler can solve problems in your facility, contact an EXAIR Application Engineer.
Last year was a big year for EXAIR’s Cabinet Cooling product line, in November we launched our first Hazardous Location Cabinet Coolers! EXAIR has always been a leading supplier in compressed air-based Cabinet Coolers, now we have expanded on that to work in the most high-risk conditions.
When a Hazardous Location Cabinet Cooleris used in conjunction with a purge system, they will keep electrical equipment at the desired operating temperature to protect and lengthen the lifetime of pricey controls and power supplies.
Electrical equipment can cause explosions in certain atmospheres. Equipment used in areas where explosive concentrations of dusts or vapors may exist must be equipped with special wiring and other electrical components for safety purposes. Hazardous (classified) locations such as these might exist in aircraft hangars, gasoline stations, paint-finishing locations or grain bins. EXAIR’sHazardous Location Cabinet Coolers have been approved and tested by UL for use in the following areas:
Class I Div 1&2 – Groups A, B, C, and D
Class I Areas refer to the presence of flammable gases or vapors in quantities sufficient to produce explosive or ignitable mixtures. Class I Div 1 will have ignitable concentrations of flammable gases present during the course of normal operations. This is level of approval is one that differentiates the EXAIRHazardous Location Cabinet Coolers from much of the competition. Class 1 Div 2 areas will have flammable gasses or vapors present only in the event of an accident or during unusual operating conditions.
Class II Div 1&2 – Groups E, F, and G
Class II areas are locations in which combustible dust may exist. The end user shall avoid installation of the device in a Class II environment where dust may be readily disturbed from the exhausts of the Hazardous Location Cabinet Cooler. Any dust formed in the vicinity of the cooler must be cleaned regularly.
Class III areas are locations that will have ignitable fibers or flyings present. This is common within the textile industry.
The Cabinet Cooler also carries a temperature rating of T3C, meaning it cannot be installed near any materials that could auto-ignite at temperatures in excess of 320°F.
The Hazardous Location Cabinet Cooler is available in (8) different cooling capacities ranging from 1,000 Btu/hr – 5,600 Btu/hr. The Cabinet Cooler is the best solution for protecting your sensitive electronics from heat, dirt, and moisture. With Nema 4/4X systems available, the Hazardous Location Cabinet Coolers will keep the cabinet cool without compromising the integrity of the enclosure.