Why Emissivity Matters in Electrical Thermal Imaging: Accurate Infrared Scanning with the Mileseey TR20 Pro
Understanding emissivity is one of the most important skills in electrical thermography, yet it remains one of the most misunderstood. Electricians rely on thermal imaging to detect dangerous heat conditions in panels, switchgear, transformers, MCCs, bus ducts, and terminations. But even the best thermal camera cannot deliver accurate temperature readings unless emissivity is set correctly—especially when scanning reflective metals like copper, aluminum, and stainless steel.
Emissivity is the measure of how effectively a surface emits infrared radiation. High-emissivity materials such as painted metal or insulated conductors emit heat accurately. Low-emissivity metals like bare copper or aluminum reflect surrounding infrared energy instead of emitting it. That reflection can cause a thermal camera to underreport temperatures dramatically. A copper lug that is internally 160°F may appear to be only 110°F if emissivity is not compensated for.
This is why emissivity is a core concept inside the Certified Thermal Electrician™ Program. Electrical surfaces vary widely in reflectivity, thermal behavior, and radiative properties. Without adjusting emissivity for each surface, thermal images can appear misleading and even dangerous. Misinterpreting a cool spot that is actually hot can result in missed faults, equipment damage, or NFPA 70B non-compliant maintenance reporting.
Our partnership with Mileseey Tools plays a big role in solving this problem. Their
TR20 Pro, available at:
offers electricians a simple, intuitive way to adjust emissivity in the field. This matters because the accuracy of an infrared inspection often depends more on correct emissivity than any other setting.
Electrical components are typically made of low-emissivity materials. Breaker lugs, busbars, stabs, motor leads, and bare conductors all tend to reflect heat instead of emitting it. When the camera sees a reflection instead of the true surface temperature, the reading can be off by dozens of degrees. That margin of error can hide a failing termination, an overloaded conductor, or a loose connection that is already in thermal runaway.
The Mileseey TR20 Pro makes emissivity adjustment straightforward. You simply open the menu, access the emissivity setting, and enter the correct value for the material you’re scanning. Bare copper often needs a value in the 0.20 to 0.30 range. Bare aluminum may require an emissivity closer to 0.10 to 0.30. Painted surfaces or insulated conductors may sit near 0.95. Once the correct emissivity is applied, the temperature reading becomes far more accurate.
Electricians can also improve accuracy by placing a small piece of electrical tape or a high-emissivity marker on the component. The TR20 Pro then locks onto that reference point and produces a stable, realistic reading. This technique is especially valuable when reflections or ambient light distort the thermal image.
When emissivity is corrected, the real thermal behavior becomes clear. Hotspots that were previously hidden now stand out. Phase imbalance becomes more detectable. Load-related heating appears more defined. Subtle thermal differences—whether between phases, legs, or components—become much easier to interpret. This level of clarity is critical for diagnosing electrical failures before they occur.
Improper emissivity settings can cause dangerously inaccurate conclusions. A component may look cool even though it is in a pre-failure state. A reflective metal surface can mimic a hot spot that isn’t actually a defect. Phase imbalance may appear where none exists. NFPA 70B maintenance reporting can become invalid if temperatures are misread. In short, emissivity mistakes compromise safety, reliability, and diagnostic accuracy.
This is why Mileseey Tools and the Certified Thermal Electrician™ Program are such a strong pairing. The TR20 Pro provides the technical capability—adjustable emissivity, stable temperature readings, clean thermal clarity—while the CTE™ Program provides the knowledge and interpretation skills electricians need to actually understand what they are seeing.
The TR20 Pro from Mileseey Tools, again available at:
is one of the best entry-to-professional-level thermal imagers for electricians because it bridges the gap between affordability and precise emissivity control. That combination makes it ideal for contractors entering the thermography field.
Emissivity is not just a setting—it is the foundation of electrical thermal imaging accuracy. Without understanding it, even the best cameras can mislead you. With proper training and the right tools, however, emissivity becomes a powerful ally in detecting failures long before they cause outages, equipment damage, or fire.
For electricians serious about mastering emissivity, thermal interpretation, and electrical thermography, the Certified Thermal Electrician™ Program provides the industry’s most relevant training. Pairing that expertise with Mileseey Tools’ TR20 Pro creates a professional-grade approach to infrared electrical inspections.
