Infrared thermography is a non-contact method for detecting temperature differences on electrical equipment like motors. It can identify potential problems in both electrical and mechanical systems, such as loose connections, bearing issues, and clogged cooling ducts. Thermography provides benefits by allowing online inspection without disrupting operations and immediately showing maintenance personnel problem areas in need of repair. Examples of thermography use include detecting unbalanced loads, overheated bearings and couplings, and hot spots on motor windings and cores.

1. Service
Infrared Termography
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2. Generalities
Electrical diagnostics
Mechanical diagnostics
• Phase electric balance;
• Vibration analysis (bearings, feet,
foundation);
• Electrical parameters analysis;
• Precision balancing;
• Insulation resistance and p.index;
• Torsional vibrations analysis;
• HV test in DC
• Impulse voltage testing (interturn
short);
Motor Diagnostic Cycle
• Pneumatic measurements;
• Laser alignment check and corrections;
• Airborne noise measurements;
• Dielectric losses parameters
measurements (tgd, capacitance)
• PD measurements
• Loop testing
• Vibration analysis;
• Airborne noise measurements
Infrared Thermography
Infrared Thermography is key in supporting both, electrical and mechanical diagnostics, while evaluating test
results and estimating real risk of failure.
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3. Why detecting temperature?
Temperature strongly affects the life cycle of an Electrical Motor.
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Statistically it has an influence on Failure Probability…
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… and it reflects into Reduced Reliability.
3 Always represents a cost, to be avaluated
depending on the specific application.
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4. Why detecting temperature?
Tools and Instruments
Tools and Instruments
An infrared camera produces an infrared image or thermogram.
It depicts the thermal radiation in a scene as emitted and reflected by the
objects in the scene based on their temperatures.
The standard image is a greytone image that shows hot objects as white
descending in greytones until black is reached, which is the coolest
temperature in the scene.
When appropriate we can colorize the image.
Infrared cameras have become compact systems that look just like a
normal video camera, are easy to use and generate a real-time highresolution image.
Software being used for reporting has been designed with the
understanding that most of the thermographic analysis work is done
at the inspection site, where all relevant data is available.
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5. Infrared Thermography
What should be thermographically checked on motor?
What should be thermographically checked on motor?
The thermal behavior of
electrical or mechanical
Frame
systems can be a powerful
clue to diagnose problems
and predict reliability of
Bearings
industrial equipment.
Heat exchanger
Terminal boxes
External fan covers
Coupling
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6. Infrared Thermography
Problems that can be detected
Problems that can be detected
Typical problems that can be detected through Infrared Thermography are:
Electrical Systems:
Loose or corroded connections.
Faulty breakers or fuse blocks.
Unbalanced loads on 3-Phase systems.
Mechanical Systems:
Excessive bearing temperatures.
Deteriorated thermal insulation.
Coupling Misalignments
Clogged cooling ducts
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7. Infrared Thermography
Problems that can be detected
Problems that can be detected
This is what you see…
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… This is what we see…
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8. Infrared Thermography
Benefits
Benefits
 The infrared survey brings many advantages, and some examples are listed below:
 Equipment and systems are inspected on-line, without production impact;
 Testing is performed while plant is in operation, at load conditions;
 Critical issues are shown to maintenance personnel immediately, without having to wait
for a report;
 Potential failures are easily located and unscheduled and unplanned downtime is
prevented;
 Infrared data correlates with other technologies including vibration analysis,
ultrasound, and motor testing;
 Large and hard to reach areas can be scanned quickly without the need for scaffolding
or ladders;
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9. On Site Experiences
Some examples of Infrared Thermography checks carried on single motor parts are listed below:
Electrical Systems:
Loose or corroded connections.
Unbalanced loads on 3-Phase systems.
Faulty breaker
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10. On Site Experiences
Some examples of Infrared Thermography checks carried on single motor parts are listed below:
Mechanical Systems:
Excessive bearing temperatures.
Coupling misalignment
Clogged cooling ducts
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11. On Site Experiences
Some examples of Infrared Thermography
checks carried on single motor parts are
listed below:
Overheating of windings and a specific hot spot
on top winding.
A fuse severely overheated
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12. On Site Experiences
Example of Infrared Thermography
checks carried on stator during Ring Test procedure:
Hot spots detected on stator core after coils removing
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