What is Infrared Thermography?Infrared radiation is thermal, or heat, radiation, which is invisible to the eye. It is produced by any object that is warmer than its surroundings.

Thermography is the process of photographing this heat energy. As an object gives off heat, the color of the infrared radiation varies according to the temperature of the object. By using a specially designed camera, a color photograph of this heat energy can be taken. The application of infrared technology has been widely used by the military in heat seeking missiles and night vision equipment. Medical and industrial uses of infrared radiation include thermal imaging, or thermography, as well.

How does this technology have a commercial or industrial application?Since all objects emit heat, an infrared camera can be used to detect and measure the temperature variations from one surface to another. Electrical systems (connections, equipment, components, etc.) emit heat as an electrical current flows through them. Should a problem in a system exist, resistance increases and heat is liberated at a rate greater than the surrounding area. This variance can be detected and measured with the use of infrared thermography.

Infrared Thermography: Determining failure or problems in electrical systems Frequently asked questions (FAQs)

Why consider having an infrared thermography survey of electrical systems?An infrared survey can help detect a problem before it manifests itself through a costly failure. These surveys are performed by qualified electrical contractors. It is very common to find a loose wire or connection that can be repaired inexpensively. However, if the system is allowed to fail, the cost could potentially inflate to thousands of dollars for equipment repair or replacement. The failure could also result in a major production outage or fire. The infrared scan is conducted while the equipment is in operation, preferably near full-load capacity, in order to get a more accurate measure of the severity of the finding.

What type of systems can be surveyed?Examples of the types of systems that can be scanned include the following:• Electrical switch gears, breakers, bus connections, and

contacts• Transformer connections• Mechanical couplings on rotating equipment• Process piping and heat exchangers• Compressor heads• Motor and generator connections, windings, feeders,

and exciters• Bearings• Drive gears and drive belts (due to friction)• Refractory systems (e.g., boilers, kilns, molten material

containments, etc.)• Steam traps and piping insulation• Tank levels and insulation problems

Craig KolakowskiRisk Consulting Manager

ARC Marine

Craig.Kolakowski@agcs.allianz.com

www.agcs.allianz.com

Infrared image of a boiling pot.

Risk Bulletin

Number 38May 2011 Report published by Allianz Risk Consulting

Allianz Global Corporate & Specialty www.agcs.allianz.com

What do infrared photos of possible electrical component failures look like?

Figure 1 below shows an electrical lead as seen by an electrician or maintenance technician.

What types of findings are reported?Taking photos of the condition of the electrical system is only the starting point. Reports can be tailored to meet specific needs. Specific information can be included in the report that can bring light to the severity of the situation. Reports typically include an image of the condition, both in infrared and visual light, an analysis as to why the condition

exists, and suggestions for correcting the problem. Reports may also include the following information:• Estimated cost to repair before failure• Estimated cost to repair after failure• Estimated business interruption to total production• Estimated number of days location could experience

business interruption

Figure 3 shows an electrical lead as seen by an electrician or maintenance technician.

Figure 4 shows the same lead in operation at 320° F. The infrared image shows a possible loose connection or overloaded circuit.

Figure 5 shows a breaker as seen by an electrician or maintenance technician.

Figure 6 shows the same breaker operating at 247° F indicating a possible overloaded circuit.

Figure 2 below shows an infrared image of the same lead at 170° F. The infrared image shows a probable overloaded circuit or loose connection which could lead to arcing or a fire.

Figure 4

Figure 5 Figure 6

Figure 3

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The material contained in this publication is designed to provide general information only. Please be aware that information relating to policy coverage, terms and conditions is provided for guidance purposes only and is not exhaustive and does not form an offer of coverage. Terms and conditions of policies vary between insurers and jurisdictions.

Whilst every effort has been made to ensure that the information provided is accurate, this information is provided without any representation or warranty of any kind about its accuracy and Allianz Global Corporate & Specialty cannot be held responsible for any mistakes or omissions.

ARC-RB-38-en

Figure 1 Figure 2