This thermogram shows the heat generated by a loose connection on the center phase of an electrical panel. Electrical connections get hot because of a defect in the component or its connections increase the resistance of the circuit beyond the original design specifications. Overloads, caused by too much power going through the component and its circuits, will also generate excess heat. The heat of defective connections and overloads is detectable by the thermal imager, making the infrared inspection of electrical systems an ideal match between technology and the application.

Most of the time, before an electrical component burns up, it heats up. Infrared thermography is used to see the excess heat so the problem can be corrected before the component fails. This advanced warning is why insurance companies have been asking their clients to get an electrical infrared inspection on their property. They want to find and repair small problems before they cause damage and loss to your personnel, equipment and company.

Some defects, which cause increased resistance and excess heat, are items such as:

  • Loose connections
  • Overloaded or imbalanced circuits
  • Faulty breakers
  • Corroded or oxidized contacts and connections
  • Damaged switches
  • Faulty fuses or circuit breakers

Natural aging, environmental conditions, manufacturing defects and/or workmanship, can cause these conditions to occur in electrical equipment. In addition, some components which should generate heat under normal operating conditions and do not, such as dead capacitors, are also visible to Thermography due to their lack of heat.


Every electrical component in a building’s electrical system, from the incoming main power line, through the fuses and circuit breaker panels to the electrical outlet or light switch, is designed not to get hot under normal operating conditions and when below its rated load. As the current approaches the rated load, the component will run warmer. When operating above the rated load, circuits will heat up, usually uniformly through out the conductive path. However, If there is a component with excess resistance cased by a loose connection, oxidized contact, corroded wires, faulty switch etc. then, at the point of increased resistance, that localized resistive connection can get very hot. During the infrared inspection, we will capture a thermogram of the problem area and enter it into the report.

Hot spots cause electrical fires. Infrared inspection of electrical systems works so well because before an electrical component burns up, it usually heats up. Thermography can locate these areas of excess heat (resistance) enabling maintenance personnel to correct the problem before the component fails. This is why your insurance company may have asked for an electrical infrared inspection of your property, to find and prevent problems before they cause damage to your personnel, equipment and facility.

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