This document provides an overview of infrared thermography and its applications for electrical systems. It discusses what infrared thermography is, how it works, common test instruments used, electrical components that can be inspected, typical faults detected, condition monitoring benefits, electrical applications, and case studies. Infrared thermography allows non-contact surface temperature measurements and visualization of thermal issues. It can be used to detect problems in transformers, distribution panels, motors, and more. Periodic inspections provide predictive maintenance benefits like reduced downtime and safety improvements.
HARDNESS, FRACTURE TOUGHNESS AND STRENGTH OF CERAMICS
Infrared Thermography Electrical Systems
1. Infrared thermography on electrical system
By
Name: Venkanagouda P.C
USN:
Under the Guidance of
Prof.Praveen .H
A seminar on
• Department of Electrical and Electronics Engineering
K. L. E. Institute Of Technology, Hubli.
1
2. Contents
Introduction
What is thermography
Test instrument
Inspection of components and faults
Condition monitoring
Electrical applications
Benefits of infrared thermography
Advantages and limitations
Case studies
Conclusion
References
2
3. Introduction
In 1800, astronomer Sir William Herschel discovered infrared
It is simply a picture of heat
On-line condition monitoring
fast, reliable and accurate temperature profile of any material surface.
New level of diagnostic aid and problem solving
Rapid growth in electric utilities and industrial sectors are embracing the
technology.
3
4. Infrared thermography_What it is?
An Infrared Camera Senses Infrared Radiation
It is objective image-giving measuring method
Enabling Us To Visualize The Thermal World
surface temperature can be determined contactless.
A Processor In The Camera Assigns Color To The Infrared Radiation-
Different Color Equals Different Temperature
4
5. In an electromagnetic spectrum the IR region appears between 0.8
micron to 1000 micron wavelength . This wavelength of IR spectrum is
more than that of a visible spectrum
5
6. Test Equipment
Hand held portable camera
Battery Powered
Range…..-20°c to +1500°c
Sensitivity…..0.1°c at 30°c
Real time display
Image Recording capability
6
7. The infrared camera evaluates and converts heat energy into
meaningful temperatures. Components in various states of failure
will emit more heat as a direct result of more energy dissipated into
the component.
7
8. Objectives of Test
To detect hot or cold area’s
To determine absolute temperature
To view Thermal profiles
To detect temperature loss
first determine a baseline
baseline is established when the system is operating under normal load and
operating conditions
the baseline images and data will be stored and compared to new data
collected from each inspection interval
8
9. Electrical Inspection Items
. Transformer
– Pad Mount
– Dry
– Overhead
• Distribution Panels
• Rectifiers
• Control Panels
• Drives
• Capacitor Banks
• Any Electrical Connection
• Main Switchgear
• Motor Control Centers
9
11. Electrical Applications
Power generation: hydro, thermal, and nuclear
Power distribution: transmission, switchyards, substations,
and distribution
Industrial users: all process and manufacturing industries
Commercial users: warehouses, office buildings, banks,
schools, virtually all buildings
11
12. Condition monitoring
No electrical system is 100% efficient
Temperature is an excellent indicator to the operating condition
It is well understood that the life of electrical components and materials is drastically
reduced as temperatures are increased.
IEEE, ANSI, IEC and manufacturers all publish standards and temperature ratings
for electrical components
the job of the thermographer to identify record, analyze and diagnose indications of
abnormal heat transfer in the electrical equipment or components
12
13. Exception Repair Priority Criteria
Priority 0
Temperature Difference 10F or Less
No Corrective Measures Required
At This Time.
Priority 4
Temperature Difference Over 100F
Corrective Measures Required Immediately
Priority 3
Temperature Difference 30F to 100F
Corrective Measures Required
As Soon As Possible
Priority 2
Temperature Difference 20F to 30F
Corrective Measures Required
As Scheduling Permits
Priority 1
Temperature Difference 10F to 20F
Corrective Measures Required
At Next Maintenance Period
13
14. Exception Example Breaker Load
Hot Spot Temperature….71F
Reference Temperature…55F
Temperature Difference..16F Repair Priority 0
No Corrective Measures Required
At This Time
92.6°F
119.1°F
95
100
105
110
115
Breaker Load A-105 amps
B-150 amps
C-167 amps
14
15. Exception Example
Main Switchboard Fused Switch
Hot Spot Temperature...311F
Reference Temperature..151F
Temperature Difference...160F
Repair Priority 4
Corrective Measures Required
Immediately
118.9°F
245.4°F
120
140
160
180
200
220
240AR01
SP01
15
16. Application in distribution system
Isolators, circuit breakers, Current Transformers, Potential Transformers,
Distribution Transformers, bus bars etc. Most faults are encountered in
the form of hot-spots at contact terminals which may be due to lose
contact, corrosive nuts & bolts, broken conductor strands etc
16
17. Applications Power Circuit of Electrical Drives
loose contacts at Motor Control Centre's
severe voltage unbalance is at the motor terminal end lead to single-phasing
This results in malfunctioning of the motor
415 volt 75 KW induction motor (101 0C) at MCC breaker terminal with
ambient about 30 0C in R-phase resulting in a voltage unbalance of about
4.7% at motor terminal
17
18. Benefits of Periodic Electrical Infrared Inspections
Predictive Maintenance...Allows Scheduling Of Repairs, Forward
Buying. The reduction in disassembling, rebuilding or repairing
components
Reduces Downtime… Find It, Repair It, Before It Blows Up and
Stops Production
18
19. Safety
Greater system security
Improved and less expensive maintenance
More efficient inspections
Reduced outage and operational costs
19
20. Advantages and Limitations
Advantages Limitations
•It is a non-contact type technique.
•Fast, reliable & accurate output.
•A large surface area can be scanned in no time.
•Presented in visual & digital form.
•Software back-up for image processing and
analysis.
•Requires very little skill for monitoring.
•Can work at a distance
•Portable
•Convincing Results
•Cost of instrument is relatively high.
•Unable to detect the inside temperature if the
medium is separated by
•glass/ polythene material etc.
•Operator experience is essential
•Filters may be needed for certain applications
•Sensitivity and Resolution reduce with distance
and angle of view
20
21. Case study 1
Consequence of Application of Thermography in a switchyard of a
Captive Power Plant
21
22. Case study 2
Transformer
Excessive transformer loading.
Excess current in the neutral of the
transformer.
Problems in the cooling system.
High harmonic content in the power
supply.
Sustained overvoltage which exists for a
long period of time.47.2°C
22
23. Case study 3
Transmission lines
23
A high-temperature spot is found at the connector of phase-T
conductor at the jumper of the riser pole.
it shows bad electrical
connection
24. Conclusions
Protect catastrophic equipment failures and unscheduled plant
shutdowns
a fast, reliable and accurate
maintenance priorities, enhance operational safety and contribute to a
stronger bottom line.
Enhancing and preserving system reliability and reducing
maintenance costs
24
=
$1.00 $4.00
25. REFERENCES
FLIR Infrared Cameras Help Detect the Spreading of Swine Flu and Other Viral Diseases Applegate.co.uk (2009-
04-29). Retrieved on 2013-06-18.
Poryev V.A., Poryev G.V. "Experimental determination of the temperature range of a television pyrometer" in
Journal of Optical Technology, Volume 71, Issue 1, pp. 70–71 (2004)
Maldague X. P. V., Jones T. S., Kaplan H., Marinetti S. and Prystay M. "Chapter 2: Fundamentals of Infrared and
Thermal Testing: Part 1. Principles of Infrared and Thermal Testing," in Nondestructive Handbook, Infrared and
Thermal Testing, Volume 3, X. Maldague technical ed., P. O. Moore ed., 3rd edition, Columbus, Ohio, ASNT
Press, 2001, 718 p..
Infrared Temperature Theory and Application. Omega.com. Retrieved on 2013-06-18..
Snell, J.; Renowden, J. (2000). "Improving results of thermographic inspections of electrical transmission and
distribution lines". 2000 IEEE ESMO – 2000 IEEE. ESMO 2000 Proceedings. Global ESMO 2000. The Power is
in Your Hands (Cat. No.00CH37183). p. 135.doi:10.1109/TDCLLM.2000.882811. ISBN 0-7803-6625-5.
http://halut.tripod.com/infrared.htm 25