Simply put, nothing. Electrical thermal imaging surveys are a highly effective way to undertake preventative maintenance for facilities management and identify defects between electrical inspection and testing. Infrared cameras, when in the hands of a trained thermographer, can yield extremely useful and reliable thermal data. When in the hands of an untrained thermographer however, mistakes can often be made.

Incorrect readings and results are often due to one of the following:

Missing Objects

Thermal imaging cameras cannot see through things – they are not x-ray cameras. Infrared cameras will only detect radiated heat from an object that’s being observed. Without a direct line of sight, faults can often be missed.

Misreading Reflections

Reflections are common in everyday life – the most common example being a mirror. When considering infrared radiation, polished and shiny surfaces (such as metals) will often reflect more. In terms of thermal imaging, this means that when standing in front of a metal surface, chances are that hotspots seen with an infrared camera are a reflection of heat from your own body. This misreading can often be confused as a fault, and can lead to costly and unneccesary rennovations.

Not Surveying Under Load

Without load an electrical system will not generate any heat. Without heat, no faults will be visible to a thermal imaging camera. Whilst this may seem obvious, it’s an extremely common mistake when carrying out electrical thermal imaging surveys.

Incorrect Settings

Unfortunately, thermal imaging cameras are not point-and-shoot. So many factors affect the output including the nature of the subject, the ambient surroundings, the range of temperatures detected and even the choice of colour palette. Emissivity, for example, is the capacity of an object to emit infrared radiation. There are several factors that can affect emissivity, so understanding its importance and how it works will ensure you don’t yield incorrect results.