Video Blog: Measuring Surface Temperature and Air Temperature Requires Different Tools

IR Temperature Guns are a great tool for measuring surface temperatures, but not the best solution for providing the air temperature data EXAIR needs to size a Cabinet Cooler system for your electronic cabinets. This brief video illustrates the differences between using an IR temp gun and a regular thermometer when gathering temperatures to determine Cabinet Cooler system specifications.

Make sure to print out the Cabinet Cooler Sizing Guide before you get started so you can easily fill in all the needed data.

Brian Farno
Application Engineer

How to size a Cabinet Cooler

The past few weeks the summer heat has decided to try and burn any vegetation that I might call a yard, so I thought it would be a good time to discuss the information that is needed to appropriately size a Cabinet Cooler® System for your electrical enclosure.

When you are inside your facility sweating because it is hotter inside than it is outside remember to think about how hot is getting in your electrical enclosure.  Maybe you don’t have to remember because the machine has been alarming out because of temperature overloads. Perhaps the operators have opened the doors and area letting all the dirt and dust be blown into the open cabinet by the fan that is now in front of it to cool it down.

I must say the fan in front of an open cabinet is something that I saw quite a bit when I was in the machine tool industry.  I would have to replace entire circuit boards in machines because the metal dust in the air from the metal-cutting had been sucked up by a fan and spit into the machine combined with oil/coolant mist and caked onto the exposed boards.  This of course doesn’t help with the component temperatures because then the heat sinks don’t perform as good.  I’ve even seen board burn, actually burn, because the metal dust had bridged two contacts that have no business touching each other.  These are just a few of the issues I’ve seen in electrical enclosures that are overheating.

With an EXAIR Cabinet Cooler® System the doors can remain closed, there’s no blue filter that can clog or fan that can short or burn up.  You don’t even have to worry about the wash down in the area if you have a NEMA 4 or 4X area because they are UL listed to maintain NEMA integrity.  The Cabinet Cooler® Systems are easy to install and even easier to maintain than any other cooling system I have ever encountered.   Mainly due to the fact that there are no internal moving parts which makes the unit maintenance free.  The only  part you may need help with is how to appropriately size the Cabinet Cooler® System for your enclosure.

In order to correctly calculate the heat load within your cabinet you will need to provide us with a few pieces of information.  We offer the Cabinet Cooler® Sizing Guide which is a simple worksheet for you to fill in the information then send it to us.  The information we’re going to need is the dimensions of the cabinet, don’t worry about whether it’s in inches, feet, centimeters, or meters, we’ll get what we need as long as they are all there.  We need to know what NEMA rating the enclosure is, 12, 4 or 4X.  If the cabinet is wall mounted or free-standing, if the enclosure is vented or not, and if so are there fans.  Then. we need some air temperatures.  In order to get the accurate temperatures a “Temp Gun” should not be used.  An example is shown below of how a roofing company uses both types of thermometers appropriately.

The reasoning for this is, the no contact laser thermometers measure the surface temperature of whatever it’s pointed at.  In order to calculate the internal heat load of the cabinet we need to know the current internal and external air temperatures of the cabinet.  When you point the “temp gun” at a component you may be getting a cool or hot spot.  The air is going to be an average temperature throughout the cabinet and tells us whether the heat is coming from the components inside the cabinet or the environment the cabinet is in.

The only other piece of information we need is the maximum external air temperature of the enclosure. Once we have this information we can easily calculate how much cooling you are going to need and appropriately size a Cabinet Cooler® System for your enclosure.

So make sure you keep the “temp guns” in the tool box and get the old-fashioned thermometer and tape measure out then give us a call.

Brian Farno
Application Engineer
Twitter: @EXAIR_BF