Infrared Thermal Imaging

Thermal imaging uses Infrared (IR) radiation generated from a material with a certain temperature. From this radiation an indication of a surface temperature can be obtained.

It is not possible to look through the test object, like with X-ray technology. If there are thermal faults present deeper inside, for instance inside the windings of a transformer, the thermal fault has to be very significantly present in order to be visible on the surface of the transformer. On the other hand, thermal faults such as loose or poorly connected bolts, leaking magnetic flux due to poorly connected magnetic shielding or bad contacts inside bushings can be made visible very well.

 

All thermal images are analyzed as relative measured values. This means that the temperature values mentioned next to the thermal images do not have to be correct and/or absolute values. The images are analyzed by searching for anomalies. For IR thermal imaging, scanning a large group of objects of the same type gives more information than a large group of different objects.