Energized Electrical Inspection
Infrared thermography is an extremely important form
of non-contact testing that has become an indispensable predictive and
preventative maintenance tool for electrical systems. Because there is no physical contact with the equipment under test, the system operates
at normal load during the inspection. Electrical and mechanical inspections, as well as heat and energy
studies, require only a fraction of the time previously needed. With infrared thermographic surveys, maintenance can prioritize repairs before failures occur.
Infrared thermographic surveys should be performed during periods of maximum possible loading, but not less than forty percent (40%) of rated load of the electrical equipment being inspected.
(NFPA 70B-1998, paragraph 18-17.5.2).
The infrared survey utilizes a portable color infrared imaging system. The equipment detects emitted radiation and converts detected radiation to a visual signal, and reproduces an image on a
LCD color viewfinder screen. a PCMCIA card electronically stores the images, visible on the monitor, when an area or component with an unusual temperature differential occurs. The difference between documented image temperatures determines the temperature rise or drop. The equipment is capable of detecting a minimum temperature difference of less than 0.5° F. Digital photographs of the equipment provide total visual representation of the area or equipment requiring attention.
For a guide to predictive maintenance, please use the following temperature rise table:
| Temperature Rise
| 2° F to 7° F
||ALERT - Possible deficiency; investigate
| 8° F to 27° F
||SEVERE - Deficiency; repair as time permits
| > 28° F
||CRITICAL - Major Deficiency; repair immediately
It must be noted that the above temperature rises / severity guide is from the NETA standards. (InterNational Electrical Testing Association)
In some instances during testing there may not be a discrepancy to report, however, it can be helpful to create a reference for comparison during future scans and testing.
If you would like us to contact you with additional information regarding Infrared thermography or energized electrical inspections, please give us a call or complete our request form.