Electrical Panel Heat Protection: Limitations of Fan Cooling

In preparation for some labor-intensive outdoor projects, I did some research into heat-related health risks, and their prevention. My first thought on prevention was getting someone else to do it, but my wife made a good case for “pride in ownership”, and I DO have a good many tools suitable for these projects. Also, I am notoriously frugal, so after getting a couple of estimates, I realized the value in a little DIY (do it yourself) and commenced planning.

High on that list of risks was the possibility of heat stroke. It’s recommended that the victim be taken to a cool space (someplace air conditioned, for example). Air flow (like from a fan) can help too, but only if they’re taken someplace where the ambient temperature is less that 95F (35C). If it’s that hot, the air flow can actually make things worse, since heat transfer requires a difference in temperature. If the cooling medium (air, in this case) is the same temperature as the object to be cooled (the human body, in this case), no heat will be transferred – and the heat stroke wins. That’s a bad day in the back yard.

This is, in fact, the exact same limitation with a popular method of electrical panel cooling: fans. We’ve been using mechanical methods of imparting motion to air for cooling purposes for a long, long time: Blowing on a spoonful of soup or a cup of coffee before a warm (but not scalding) sip, waving hand fans at oneself during indoor gatherings, installing electric fans in those same buildings, and the list goes on. Fans are inexpensive to purchase & operate, come in a variety of sizes & configurations, and are oftentimes used to circulate cooling air through occupied rooms, confined spaces, and, of course, electrical & electronic panel enclosures.

These are quite effective for panels with moderate-to-high internal heat loads, as long as the ambient area temperature is less than the temperature you wish to cool the panel’s internal air to. In those situations, the only real concern is the quality of the air in the environment. As you can see in the photo to the right, filters are an absolute “must”, and they’re going to require regular maintenance. This means cleaning or replacing the filters, as well as cleaning the fan grills and blades themselves. It’s still very likely that some of that dust is going to get inside the enclosure, and while we’re on the subject of environmental contamination, so will humidity. I probably don’t need to tell you that dirt and/or water, and electricity, don’t mix.

There are other methods of cooling (panel a/c, thermoelectric coolers, water cooled heat exchangers, heat pipes, etc.) that limit environmental contamination, but they’re still going to need periodic (oftentimes frequent) attention: filters will clog, refrigerant coils will get fouled and corrode, moving parts will wear, motors & switches will burn out, etc. Even with the advances made in refrigerant technology, the leaks that panel a/c and heat pipes are prone to are still bad for the environment.

If this sounds like your environment, and you’re looking for safe, dependable, durable heat protection, look no further than EXAIR Cabinet Cooler Systems. Using the Vortex Tube phenomenon, they generate cold air from your compressed air supply, with no moving parts to wear or electric devices to burn out. Systems are on the shelf & ready to ship in cooling capacities to 5,600 Btu/hr. We also “tailor-make” systems for higher heat loads, from stock products, that can usually ship right away as well. Once installed on a sealed enclosure, the only thing the internals of that enclosure are ever exposed to again is clean, moisture free, cold air. All of our Cabinet Cooler Systems come with an Automatic Drain Filter Separator – the only preventive maintenance that’s ever required for the systems is the periodic replacement of the filter’s particulate element.

Inside, outdoors, high temperature, dirt/dust/humidity, corrosive and classified environments are no problem for EXAIR Cabinet Cooler Systems

We can quickly and accurately specify a Cabinet Cooler System to meet your needs with just a few key pieces of information – you can fill out a Sizing Guide (or complete one online) and send it in to us, or you can call an Application Engineer with the data. It only takes a minute to do the calculations, and we do them over the phone all the time. Installation is straightforward and usually only takes a matter of minutes. We have a number of short “how to” videos on our website that cover all aspects of installation, and if you ever have specific questions or concerns, an Application Engineer is a phone call away. We look forward to hearing from you!

Russ Bowman, CCASS

Application Engineer
EXAIR Corporation
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Compressed Air Amplifiers Outperform Fans for Cooling Parts

When seeking a suitable solution for cooling or drying your parts, you may be tempted to try out a low-cost fan to get the job done. While fans do a great job of keeping you cool during the warmer months, they’re not the best choice for cooling or drying parts. Have you ever noticed that when standing in front of a fan the flow pattern is not consistent? This is due to the nature in which the fan blades create that air flow by “slapping” the air as they spin rapidly. The air flow that exits from the fan is turbulent and is not as effective as the laminar air flow pattern that is produced by EXAIR’s Super Air Amplifier. The Super Air Amplifier utilizes a patented shim design that maintains a critical position of the air gap and creates a laminar air flow pattern that will exit the outlet of the unit.

fan data2

In addition to providing laminar air flow more conducive for cooling and drying, the Super Air Amplifier provides much more air that can be directed at the target. A standard 2.36” x 2.36” DC operated fan provides anywhere from 12-27 CFM at the outlet, depending on the model. For comparison, a Model 120022 2” Super Air Amplifier will provide 341 SCFM at the outlet when operated at 80 psig. At just 6” away from the outlet, this value increases to 1,023 SCFM!! When compared to the fan outlet air flow, the Super Air Amplifier produces more than an 1,100% increase in air volume!

When replacing a fan with a Super Air Amplifier, the process time can be dramatically reduced. The increase in air volume significantly reduces the contact time that your part will need to be exposed to the air flow, allowing you to increase your line speed and decrease the overall production cost of the part. This is achieved due to the nature in which a Super Air Amplifier draws in air from the ambient environment. At amplification ratios as great as 25:1, the Super Air Amplifier is the best way to move a lot of air volume across the part with very little compressed air supplied to it. Check out the video

In addition to providing laminar airflow and increasing the volume of air, the Super Air Amplifier is also infinitely adjustable through one of two ways. Each size Super Air Amplifier has a shim set that can be purchased. Swapping out the stock shim for a thinner shim will reduce the compressed air consumption, force, and flow. Installing a thicker shim will increase it. Additionally, the force and flow can also be adjusted by regulating the input supply pressure through the use of a pressure regulator. With sizes ranges from ¾” up to 8”, there’s a Super Air Amplifier for all applications. Give us a call today to see how you can optimize your process by replacing your fans with one or more Super Air Amplifiers.

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

Intelligent Solutions for Electrical Enclosure Cooling Educational Webinar

Warmer temperatures are quickly approaching, which may seem like a welcome change for personal reasons, but in a processing line, the increased temperatures can wreak havoc on sensitive components found in an electrical control panel.

EXAIR Corporation will be hosting a FREE webinar titled “Intelligent Solutions for Electrical Enclosure Cooling” on May 23, 2018 at 2:00 PM EDT.

(click on the photo to register – it’s FREE!)

By attending this interactive session, you will learn the difference between the 3 most common NEMA ratings for electrical control panels found in an industrial setting, NEMA Type 12, 4 and 4X. We’ll provide examples of traditional, yet unreliable, methods of cooling and the concerns associated with using these types of devices.

Next we will explain how ignoring heat related issues can cause machines to shut down due to failed electrical components, resulting in lost production and increased maintenance costs, negatively affecting a company’s bottom line.

In closing, we’ll show how using an engineered, compressed air operated solution can reduce  downtime by providing a low cost, maintenance-free way to cool and purge control panels with no moving parts.


Justin Nicholl
Application Engineer

A Tale Of Two Cooling Applications

There are many, many ways to cool something down. Which method works best will depend on a number of factors, but the biggies are:

*How hot is it?
*How cool do you need it?

If you call EXAIR to discuss a cooling application, these are most likely the first questions that’ll be asked. And the answers will determine which product line we start talking about. In the title of this blog, I promised you two tales…here’s the first:

A caller from a metal fabricating shop needed to cool down metal cylinders after they were heated to 400F, and was curious to know if this was a good application for one of our products. Now, he had already answered one of our questions, so the answer to the second would tell the rest of the tale.

Turns out, they only needed to get down to 120F or so, which made this an excellent application for our Super Air Knives…they’re going to blow a laminar, high volume flow of ambient temperature air onto the part. We knew this from a past application that was so well documented that we included it in our catalog…you can read all about it on page 21 (if you don’t have one, get one – it’s free.) But for now, here’s a graph of the cooling rate comparison with the Super Air Knife:

While the fans no doubt made for large volume air movement, the laminar flow of the Super Air Knife resulted in a much faster heat transfer rate.
While the fans no doubt made for high volume air movement, it was also very turbulent.  The laminar flow of the Super Air Knife resulted in a much faster heat transfer rate.

When I showed this to the caller, that was all the convincing it took…their goal was to reach 120F in about a minute and a half.  Which, as you can see, will be no problem for the Super Air Knife.

Tale #2 is a bit different.  This was from a firearms manufacturer who needed to cool small, but hot, parts quickly, and they needed to reach room temperature.  Looking at the graph above, we know that blowing room temperature air on a hot part will cool it rapidly, until the temperature of the part begins to approach room temperature.  The solution?  Colder air, of course!

Enter the EXAIR Vortex Tube…after some discussion of the part size, shape, and their compressed air capacity, we determined the Model 3215 Medium Vortex Tube should be suitable for their operation.  By generating a cold air flow of about 20F, this replicated the higher temperature differential we see in the left-hand side of the cooling graph above…where the cooling rate was the highest.

If you’d like to talk about how “cool” an EXAIR product can make your application, give me a call.

Russ Bowman
Application Engineer
EXAIR Corporation
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