Topics: Electrical Maintenance Safety Devices, Infrared Windows, Thermography, Electrical Inspection, Energized Electrical Maintenance, ultrasound, IR Cameras, Polymer IR Window, polymer infrared windows, Environmentally Sealed
This video in the IRISS E Learning Series discusses the 10 main advantages of the IR Polymer Windows over Crystal IR Windows. The 10 points outlined in this short video demonstrates the superior benefits of the Polymer IR Windows. Polymer IR Windows were designed to specifically overcome the failure modes of the crystal infrared windows.
Topics: Electrical Maintenance Safety Devices, Infrared Windows, Thermography, certifications, Electrical Inspection, Energized Electrical Maintenance, IR Cameras, Crystal Optic, Crystal IR Window, Polymer IR Window, polymer infrared windows, crystal infrared windows
Over the years I have been involved in the infrared industry I have seen some mistakes made and problems missed using spot temperature measurements on IR cameras, luckily these were rectified using the IR software when the reports were written… (would not have been the case had we been using “report by exception” techniques!).
Spatial Resolution is also known as the Instantaneous Field of View (IFOV) or Spot Size. The limitations of the spatial resolution are due to the size and expense of the focal plane array (FPA). The FPA of many moderately priced IR cameras will have an array of 320 x 240 or 160 x 120 detectors. This may make it difficult to determine the temperature of small targets at a long distance...
A simple way to check the transmission rate of any infrared window is the “coffee cup test.” Use this test before your initial installation and during regular IR window maintenance for windows with materials that are known to degrade over time.
Many people are not aware that the detector in an infrared camera actually only reads electromagnetic radiation it receives in a specific range of wavelengths. In order to display this in a useful reading the camera makes several calculations in order to convert the actual data to a temperature. The emissivity and transmissivity (sometimes depending on the camera manufacturer) have to be manually entered into the camera’s menu. if this value is entered incorrectly the actual temperature will be exponentially different (see Stefan-Boltzmann’s Law) than the displayed temperature. The old saying of “well as long as it is consistently wrong the change will be noted” is not entirely correct either, as the difference between phases will also be exponentially wrong. The error is going to be worse as the temperature rises – if the differential between the measured temperatures is significant then the displayed temperatures could be significantly different!
Every infrared camera defines its Field of View (FOV) across a horizontal/vertical axis.
You have two ways to determine the Field of View (FOV) on your camera:
- You can calculate the FOV using the formula: 2 x the tangent of ½ the angle x distance
- You can measure (and “map out”) the practical FOV with a quick field test to check your math!
The practical FOV test is quick, relatively easy, and in no way requires a scientific calculator!