The analysis we carry out can be carried out in three different ways:
In this type of inspection the technician carefully examines all the components in the field.
Thermographic images are taken only of components with problems.
This inspection is the version that has lower costs and is suggested for purely maintenance purposes, for periodic checks after the first inspection, or if your company wants to keep costs down or needs the report very quickly.
It is also the basic inspection to access the facilities provided in the INAIL OT23 module.
The second type of inspection is carried out with the thermographic acquisition of all the components that present problems and also the most important components that do not present anomalies.
In this case, the costs and time will be slightly higher because the acquisition in the field and the report takes a little more time.
This is the method that allows keeping track of the evolution of important components.
Thanks to our software we are in any case very fast in the perfect evaluation of thermograms.
Finally, we can perform a thermographic inspection with the complete acquisition of all the images.
Once this is done, we create a complete report with all the images of all the components inspected.
This is the typical analysis required for critical installations by companies (e.g. those who manage high voltage substations) who want to have a complete guarantee that all components have been carefully examined.
In this service, on request, it is also possible to supply thermograms in radiometric format.
We control individual electrical components one by one from a suitable distance. We do not make unnecessary overviews. Very often, in fact, improvised technicians overlook the fact that for a correct temperature analysis thermographic images must be acquired from the correct distance.
The size of the area analysed by a single pixel of the thermal imaging camera is a fundamental parameter for accurate measurement and, in the datasheets, it is indicated as “IFOV Istantaneous Filed of View” or “Spatial Resolution”.
The smaller the IFOV value, the better the thermal imaging camera.
Many untrained or technically unprepared thermographic operators overlook the fact that if the object to be measured has a smaller size than is conventionally considered:
Minimum size (in mm) = 3 x IFOV x Distance (in metres)
The temperature measurement could be wrong and therefore also the evaluation of the severity of the problem.
That’s why we at DarkWave Thermo use thermal imaging cameras with the best possible IFOV and telephoto lenses, to precisely and accurately analyze small objects or objects at great distances.
You can trust our judgment.
We confirm with you which is the best evaluation criterion with which to assess the problems identified: taking it from the technical literature, from what the insurance company requires, from the manufacturers’ indications.
Usually, we use a criteria called “Delta T” which compares the temperatures reached by a component compared with similar components under the same operating conditions.
Sometimes it may be necessary to use the absolute temperature criterion, when we have no terms of comparison and when it is necessary in any case to verify the gravity of the temperature reached by the individual components, in relation to the temperature of the air around them.
Two possible criteria based on the Delta T measurement that we use are shown in the attached tables.
A possible criterion based on the Delta T measurement that we use is the following:
Another possible criterion, suggested by the International Electrical Testing Association (NETA), is that based on both Delta T and absolute temperature measurements. As reported in the following table: