After most folks attend a Level I Thermography course, they’re very excited to go out and find problems and practice what they’ve learned.  Obviously from the standpoint of their employer, this is a good thing but it’s also imperative for one’s continuing education. Like any other skill, if you don’t use your imager often enough, you’ll lose your edge. Spending time inspecting equipment is something to be encouraged.

Si está leyendo el título de este documento y no reconoce los términos utilizados, por favor no haga click para cerrarlo y lo invitamos a seguir leyéndolo. En The Snell Group, nos esforzamos en entregar conocimiento en todo el espectro tanto de la Termografía Infrarroja así como también del Mantenimiento Centrado en la Confiabilidad (RCM, por sus siglas en inglés).

"In-Rush", or starting current, provides an invaluable trend-able data set. It can be used to identify starting circuit faults, motor circuit faults, motor-rotor/stator faults, and mechanical faults.

As the sun works its way across the skies, the shadows it casts can become long and influential. This is especially true on walls where a soffit or overhang can shade the upper part of a wall but not the lower. This is obvious to anyone looking at the exterior (above image), although even there you may see, thermally, the time lag of the moving shadow (see the shades of blue (image right) at the red line).

The visual image above is a duct of a transformer showing no visual indication of heat-related failure.

Using thermal imaging to determine both the source, cause, and severity of a hot spot isn’t always easy. Just because you see a thermal anomaly doesn’t necessarily mean you have located the source of the abnormal heating. In almost all cases, thermographers are only detecting heating that has by some method of heat transfer, conduction, convection, or radiation, migrated to an area where they have a direct line of sight.

The use of impedance values can provide a rapid and conclusive means of localizing the source of anomalous data to the rotor, stator, or motor circuit. All of the major motor tester manufacturers provide various data formats to achieve analysis.

Let’s look at the basics. Impedance is the vector sum of resistance, inductance, and capacitance. Inductance and capacitance are 180 degrees apart in their phase relationship and 90 degrees displaced from resistance. The vector sum of these values is “impedance.”

De preguntar a algunos usuarios experimentados de la Termografia acerca de los posibles puntos débiles de las cámaras termográficas actualmente en el mercado, muchos podrían indicar las baterías.

Si realizamos una búsqueda rápida en internet acerca de ‘Mantenimiento Centrado en la Confiabilidad’ podríamos encontrar cientos de links con información, o aun compañías que aplican muchas diferentes tecnologías de monitoreo de la condición de los equipos. Aun cuando este es un tema de actualidad para muchas compañías, podrían existir empresas o plantas que practican la vieja escuela de mantenimiento donde típicamente se realizaba una sola inspección anual a algunos de sus equipos, usualmente eléctricos, sin un programa claro de mantenimiento.

One of the first sayings I heard when I began using thermal imagers 28 years ago was "all heat loss from windows disappears above the third floor." Somewhere around the same time, after having looked at many windows, I quickly learned to use the term "appears to be" when referring to thermal images, especially those taken of buildings. It quickly became very clear why "appears to be" is an important saying that is appropriate for use by the thermographer.

If you were asked as a thermographer to try and identify the weakest link to be found with the variety of modern (i.e., reliable & feature-rich) thermal imaging systems available in the marketplace, many of you might be resigned to just saying it is the battery.  Pretty much any new camera out there does everything you need and then some.  Even battery life is now typically outstanding, lasting upwards of 4+ hours for many models.