Infrared Inspections

Infrared inspections, also known as thermographic inspections or thermal imaging, involve using infrared cameras to detect and visualize heat patterns emitted by electrical components. Here are the key reasons why you should consider regular infrared inspections for your electrical equipment:

  • Overheating Issues:
    Infrared inspections can detect overheating electrical components such as wires, switches, circuit breakers, and connections. Overheating is a common precursor to electrical failures and can lead to fires or equipment damage. Detecting these issues early can prevent catastrophic failures.
IR Fuse Image
  • Failure Prevention:
    By identifying and addressing potential issues before they escalate, you can prevent unplanned downtime in your facility. Downtime can be costly in terms of lost production, revenue, and repair expenses.
  • Increase Equipment Lifespan:
    Regular inspections can extend the lifespan of electrical equipment. Overheating and electrical stress can accelerate wear and tear, leading to premature equipment failure. Addressing issues early can help equipment last longer.
NETA Test Procedure
Thermographic Survey
NETA ATS-2017
Thermographic Survey
1. Visual and Mechanical Inspection
  1. Perform thermographic survey when load is applied to the system.
  2. Remove all necessary covers prior to thermographic inspection. Use appropriate caution, safety devices, and personal protective equipment.
  3. * Perform a follow-up thermographic survey within 12 months of final acceptance by the owner.
2. Report

Provide a report which includes the following:

  1. Description of equipment to be tested.
  2. Discrepancies.
  3. Temperature difference between the area of concern and the reference area.
  4. Probable cause of temperature difference.
  5. Areas inspected. Identify inaccessible and unobservable areas and equipment.
  6. Identify load conditions at time of inspection.
  7. Provide photographs and/or thermograms of the deficient area.
  8. Recommended action.
3. Test Parameters
  1. Inspect distribution systems with imaging equipment capable of detecting a minimum temperature difference of 1° C at 30° C.
  2. Equipment shall detect emitted radiation and convert detected radiation to visual signal.
  3. Thermographic surveys should be performed during periods of maximum possible loading. Refer to ANSI/NFPA 70B, 2010 Edition, Section 11.17.
4. Test Results
  1. Suggested actions based on temperature rise can be found in Table 100.18.
NETA ATS-2017
9. THERMOGRAPHIC SURVEY
1. Visual and Mechanical Inspection
  1. Inspect physical and mechanical condition.
2. Thermographic Survey Report

Provide a report which includes the following:

  1. Description of equipment to be tested.
  2. Discrepancies.
  3. Temperature difference between the area of concern and the reference area.
  4. Probable cause of temperature difference.
  5. Areas inspected. Identify inaccessible and/or unobservable areas and/or equipment.
  6. Identify load conditions at time of inspection.
  7. Provide photographs and/or thermograms of the deficient area.
  8. Provide recommended action for repair.
3. Test Parameters
  1. Inspect distribution systems with imaging equipment capable of detecting a minimum temperature difference of 1° C at 30° C.
  2. Equipment shall detect emitted radiation and convert detected radiation to visual signal.
  3. Thermographic surveys should be performed during periods of maximum possible loading. Refer to NFPA-70B.
4. Test Results
  1. Suggested actions based on temperature rise can be found in Table 100.18.
NETA ATS / MTS
TABLE 100.18
Neta Table 100.5

Temperature specifications vary depending on the exact type of equipment. Even in the same class of equipment (i.e., cables) there are various temperature ratings. Heating is generally related to the square of the current; therefore, the load current will have a major impact on ΔT. In the absence of consensus standards for ΔT, the values in this table will provide reasonable guidelines.

An alternative method of evaluation is the standards-based temperature rating system as discussed in Chapter 8.9.2.2, Conducting an IR Thermographic Inspection, Electrical Power Systems Maintenance and Testing, by Paul Gill, PE, 2008 edition.

It is a necessary and valid requirement that the person performing the electrical inspection be thoroughly trained and experienced concerning the apparatus and systems being evaluated as well as knowledgeable of thermographic methodology.