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www.infraspection.comCopyright 2004 Infraspection Institute

Infrared Thermography &Passive Ultrasound for

Electrical System Inspections

Ultrasound World II ConferenceClearwater Beach, FL

November 6-9, 2005


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Infrared Thermography use of a thermal imager to detect,

display and record the thermal patterns and temperatures

across the surface of an object

Passive Ultrasound use of an ultrasonic translator to

detect, measure and record sound patterns for an object

Traditionally, these technologies have been used

individually; however, combining them overcomes

limitations of each and can provide complimentary data

Introduction


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Typical Modern Imagers


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www.infraspection.com

Camera Sensitivity

Imagers can detect delta Ts as small as 0.1 C

Handprint on table detectable for up to several minutes


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IR and Ultrasound for Electrical Distribution Systems

Uses: Preventive/Predictive MaintenanceCondition Monitoring

Quality Assurance

Forensics


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Common Causes of Thermal Anomalies

Loose/deteriorated connectionsImbalanced Loads

Overloads

Open Circuits

Inductive HeatingHarmonics

Defective Equipment


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Common Causes of Ultrasound Anomalies

Corona

Arcing

Tracking

Partial Discharge


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Loose/Deteriorated Connections


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Imbalanced Loads / Overloads


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Open Circuits


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Inductive Heating


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Destructive Harmonics


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Blocked Transformer Radiators


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Low Oil in OCB


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Defective Insulators


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Defective Lightning Arrestors


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Resist temptation to provide repair recommendations Apparent loose connection due to defective internal contact

Breaker causing power outages

Replacement was required

Clear Line of Sight Not Always Possible


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Avoid using temperature rise as a severity indicator

Bushing indicated low to moderate temperature rise of 10 F

Problem due to loose internal connection with arcing

Arcing can cause sudden catastrophic failure!

Diagnosing Exceptions & Recommendations


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Airborne ultrasonic testing complimentary to IR

Uses ultrasound translator to detect ultrasonic

frequencies associated with corona, arcing &

tracking

Same preparations as IR Inspections

Training and certification recommended

Airborne Ultrasound


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Corona

Tracking

Arcing 26.8

24.4

*>28.4F


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Clear line of sight required

Equipment must be under load

Atmospheric conditions can affect results

IR equipment can affect accuracy

Safe work practices must be used

Results dependent upon operator skills Proper training imperative for success!

Key Points


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Technologies require same preparations

- Save preparation time

Technologies compliment each other

- Detect problems that individual technology could miss

Combined technologies:

- Are completely passive

- Are non-destructive

- Require no interruption of service

- Can be performed remotely

- Can help to improve reliability & reduce downtime

Benefits of Combining IR & Ultrasound


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Who is Infraspection Institute

Independent organization providing training, certification and

support for infrared thermographers.

Our Level 1, 2 and 3 Certification courses meet the training

requirements for NDT personnel in accordance with the ASNT

document, SNT-TC-1A.

Since 1984, Infraspection Institute has trained nearly 7000 Certified

Infrared Thermographers worldwide.

Recognized by the US Office of Patents &

Trademarks only Infraspection Institute is authorized

to issue the Certified Infrared Thermographer markto qualifying individuals.


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How We Can Help You

We support the practicing thermographer in order to helpyou get the most from your IR inspection program!

We maintain a comprehensive website containing thermalimages, class schedules and information aboutthermography.

For more information or to register for classes,

Call: 609-239-4788

Online: www.infraspection.com

Online: www.irinfo.org

IR Training for the REAL World


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About the Instructor

R. James Seffrin is a Level III Certified Infrared

Thermographer with over 20 years field experiencein commercial and industrial thermography.

Jim has authored several papers and technical

articles on thermography. He has co-authored

several standards including the Infraspection

Institute Guidelines. He has also worked as anexpert witness in legal cases in several states and

in Europe.

An Infraspection grad in 1984, Jim joined

Infraspection as an instructor and curriculum

developer in 1997. Jim became Director of the

Institute in 2000. You are likely to meet Jim at oneof our courses or at our annual IR/INFO

symposium.

7 infrared thermography

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