What is Infrared?
I’ve written a bit about infrared inspections already, what you should expect from the service, and what happens once your study is finished. You know that infrared is an inexpensive way to diagnose your property and get a better look at your electrical system’s health. Because infrared scanning allows us to see things that we can’t with our own eyes, you know that it’s a great way to stay ahead of the curve when it comes to your building’s hidden problems. But what exactly is infrared thermography? It’s not magic, and it’s not a new science. I think the more you know about the process, the better you will be able to appreciate its benefits.
Infrared thermography is a type of imaging involving the use of electronic optical devices to detect and measure radiation, which is then translated into temperature values spread across a surface. This technology works on anything that has a temperature above 0° Kelvin (approximately -459°F). The cameras that are able to detect this spectrum of radiation wavelengths operate similarly to many digital cameras today, with a few exceptions. The lens directs information to a sensor that captures and reads the information, an internal processor then makes the information usable, and a screen displays a colorized image that our eyes can understand. What sets infrared cameras apart from modern DSLR and mirrorless cameras are their advanced technologies, such as quantum detectors and sophisticated cooling systems, but your pocket camera probably takes a much better selfie.
Did I lose you yet? What if I told you we used the cameras to look for ghosts? Because we did. Cool, right? No luck yet, but we’ll keep trying.
The short version is this: Infrared is not X-Ray. While this technology has come a long way for maintenance professionals, the process is still completely visual. Now, while there are cameras specifically geared for geothermal activity and gaseous substances that aren’t necessarily visual in nature, consider this:
Fluids are substances that flow and conform to the outline of their container. Infrared radiation is a measurement of heat on an object or environment. A fluid with a specific temperature underground will slowly transfer that heat to its container, which would be the surrounding earth. A gaseous substance will do the same to the ambient temperature of a room, exactly how an HVAC system can quickly accommodate a large tenant space.
Now with that in mind, let’s turn our focus to electrical maintenance. Your breaker panel has covers to protect operators from electrical hazards. Some of the connections behind the panel may be hotter than those around them, but they are not touching the covers. The heat generated will not transfer efficiently to the surrounding metal, and therefore, an infrared camera will not be able to give the inspector a firm understanding of what is going on inside the panel. This is the reason why it is so important for infrared inspector to remove the necessary covers from the equipment they are scanning. If the inspector cannot see what he is scanning, neither will the camera, decreasing the diagnostic value of the process.
The following images show the same breaker panel at different stages of the inspection, and what an infrared camera is able to capture at each stage.
Thermographic imaging is a visual process, and I need you to remember this information. My goal is to equip you with the necessary knowledge regarding the infrared process, so that you can better communicate with your inspectors and get the most out of an infrared service.
At SI Testing, we use FLIR cameras and for all our infrared work. FLIR is a great resource for more information on infrared technologies and applications. If you have any questions about the benefits of infrared inspections or the process itself, don’t hesitate to contact us.