Infrared thermography is an ideal inspection technique for scanning electrical equipment for defective components. Normal wear, chemical contamination, corrosion, fatigue and faulty assembly or installation, any of the above may lower the conductivity and raise the resistance level of the component in question. Such a rise in component resistance will increase the amount of power dissipated in the form of heat. This in turn will cause an increase in the temperature of the component.
This excessive heat, evidenced by the increased surface temperature of the component, can be readily noted and the temperature rise measured by the infrared system. The increased temperature indicates a potential trouble spot and possible future failure of the component.
The infrared inspection is carried our while the electrical system is under load and there is no physical contact with the system, thus making it an excellent preventative maintenance tool, which causes no disruption to the normal operating routine of a facility.
At the plant/building level all the major electrical equipment such as the sub-station, motor control centers, switchgear, circuit breaker panels, electric motors, etc. can be readily checked for component problems, which are at an excessive temperature, thus indicating potential problems.
In power generating, transmission and distribution systems electrical energy is transferred from one facility through a series of mechanical interfaces associated with connectors, insulators, switches, bushings, and buses, etc. each resultant temperature increase, again pointing to a potential problem.
Routine infrared scanning of electrical components is thus a valuable preventive maintenance tool whereby early corrective action may be taken preventing costly breakdowns and/or plant hazards.