Why surge testing is so important

Electrical Equipment Company - eecoonline.com

Electric Motor Surge Testing Why surge testing helps detect motor failures.

Things you need to tell your motor shops.

Surge Testing Predicts Electric Motor Failure


Electric motor surge testing helps identify a shorted motor conductor turn and is a predictor of future motor failure due to turn-to-turn shorting.

Root Causes of Failure


Electric Motor Insulation as Root Cause of Failure

Failure of electric motor conductor insulation is a first sign that motor is going to fail. Root cause of failure is often insufficient insulation on windings, especially at turns.

Motor Insulation Damage

Chemical deposits on motor windings break down electric motor insulation. Movement of winding during start-ups causes excess wear on insulation.


http://www.eecoonline.com/repair-practices-insulation-resistance-test/

Electric Motor Surge Testing Essentials


80% of electric motor failures start out as turn-to-turn faults. Motor Surge Testing needs to be part of a comprehensive maintenance program.


Surge Testing Can Lower Failures

http://www.eecoonline.com/motor-repair-best-practices-surge-testing/


SKF Power Packs Baker PP30, Baker PP40 and Baker PP85

A surge test is conducted with a Baker type testing machine, following accepted procedures.

Baker-Type Surge Testing

http://www.skf.com/group/products/condition-monitoring/portables-data-collectors-and-analyzers/electric-motor-analyzers/static-motor-analyzers/power-packs/index.html









Motor technician connects a Baker-type test machine to load side of motor starter. A voltage pulse is placed across two of the three electric motor winding conductors.


Testing Procedure


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Motor Testing Procedure

Test is then repeated for all three pairs of motor windings to enable comparison. Common problem is motor shops not understanding proper voltage levels.


Understanding Correct Electric Motor Testing

Standard

Know the Proper Standard

Test is for the dielectric strength of motor insulation separating the turns within a form wound coil.


http://standards.ieee.org/findstds/standard/522-2004.html


To calculate motor voltage, define the type or condition of motor coils, as shown below.


Common Motor Testing Standards

Correct Motor Voltages Will Vary

http://www.eecoonline.com/wp-content/uploads/2014/02/Motor-Repair-Services-Program1.pdf

IEEE 522 Levels

Ensure that your motor shops use proper voltages for surge testing. Voltages below are per IEEE 522.


Applying Correct Voltage Levels

Waveforms Confirm Successful Test

Uniform Oscilloscope WaveForm


An ideal motor surge test on an oscilloscope will display a uniform waveform. All three sets of windings must be acceptable.




Ask Questions, Avoid Failures

Ask your motor shop which standard they use for surge tests. Low and Medium Voltage Motor Repair Service Center (Shop) Selection Guide


http://www.eecoonline.com/low-and-medium-voltage-motor-repair-selection-guide/




Visit our website for the motor testing standards guide. Ensure that your motor shop follows the proper standard.

For assistance or a consult contact [email protected]

or call 800.993.3326


http://www.eecoonline.com/low-medium-voltage-motor-testing-common-standards/

mailto:[email protected]

Engineering

Why surge testing is so important