A point often underestimated during electrical inspections:
Shiny copper busbars behave like mirrors.
Their emissivity is extremely low — typically 0.03 to 0.05.
For an infrared camera, this means one thing:
you are not measuring the true temperature.
Without proper surface preparation:
- A busbar at 100°C may appear closer to 30°C
- The thermal risk is seriously underestimated
- The diagnosis becomes unreliable
That’s exactly why emissivity targets (black stickers / patches) are used.
- Known emissivity around 0.95
→ allowing the camera to capture the real thermal signature rather than reflections.
A thermographic report showing “hotspots” on bare shiny copper without emissivity correction should always raise questions.
This is not a gadget.
It’s essential for:
- condition-based maintenance
- arc fault prevention
- reliable electrical safety assessments
Respect to the panel builders, installers, and maintenance teams who apply these simple but critical details in the field.
