by scottwallis1 | Nov 1, 2017 | Blogs, Electrical Related
Thermal imaging cameras translate thermal energy (heat) into visible light to allow us to analyse an object or scene.
They provide us with an image of temperature distribution on a surface or object. They can be used for immediate diagnosis or processed through specialised software for further evaluation, accuracy and report output.
Cameras and Software are loaded with many colour palettes that can be utilised, and the palette you use is generally a matter of personal choice.
Beyond impressing your customer with great images the main objective is to deliver useful data, accurately and clearly.
Below we have a main power switch in a compressor panel. There is a defective connection on ph2 between the busbar and the terminal.
Image 1, a typical thermogram that highlights the anomaly very clearly. In many circumstances, this would be the image i would use for my report.
004 Intec Analysis – Main power switch busbar connection.
Image 2, the same image with the Active ROI scaling mode applied to the anomaly area. This allows you to assess the values within the selected ROI only. Temperature data below 52 C is blacked out of the image. The thermal gradient is presented very clearly.
005 Image 2 – Active ROI (region of interest)
Both images are very relevant for different reasons. As explained the priority is to deliver the data clearly and precisely, however sometimes it’s good to experiment and in some applications we may need to isolate all other temperatures in order to monitor heat distribution.
Thank you.
by scottwallis1 | Oct 30, 2017 | Blogs, Electrical Related
Overheating can damage electrical circuit components and can cause fire, explosion and injury. The potential catastrophic consequences of electrical system failure and hazards must be avoided at all costs.
Predictive maintenance (PdM) inspections on electrical systems allow companies to detect and correct problems early. This helps to avoid equipment shut down, loss of production and safety incidents.
It is important that the person conducting the inspection is not only adequately certified, but that they also use the correct thermal camera for the task in order to achieve reliable results.
Two key features of a thermal camera that should be understood for optimal results from an electrical predictive maintenance inspection.
Thermal resolution is important in thermography. Every single pixel is a measuring point, therefore the higher the resolution, the more measurement points you have and the more accurately you will measure. When you measure more accurately, you detect anomalies earlier, avoiding unnecessary damage for your customer.
When you look at a normal photograph on a digital screen, you’re really observing thousands of individual little points of colour. In the same way, radiometric thermal imaging cameras capture temperature data for each of the thousands of points in what we call a thermogram or thermal image.
The other feature that is equally important is thermal sensitivity (NETD, or Noise Equivalent Temperature Difference).
This is expressed the ability of an infrared camera to display a very good image even if the thermal contrast in a scene is low. A camera with good thermal sensitivity can distinguish between objects that have very little temperature difference between them.
006 Defected connections.
Both features described above are critical for a successful inspection yet are often overlooked. For lots of applications, lower budget thermal cameras are sufficient, electrical predictive monitoring is not one of them.
The goal after all, is to avoid equipment break down, loss of production and most importantly safety incidents.
Thanks for reading.
