Notes

8 Motor parts and common faults 

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Straight forward list of some common motor faults:

  1. Shaft - Imbalance, Misalignment, Wear
  2. Rotor - Imbalance, Rotor Bar Faults, Loose Rotor, Eccentricity
  3. Stator - Stator Looseness, Incorrect Air Gap, Winding Fault
  4. Motor Bearing Housing -Mechanical Looseness, Misalignment
  5. Rolling Element Bearings - Cage, Ball/Roller, Outer and Inner Race Defects Looseness within the bearing
  6. Motor Feet - Structural Looseness/Soft Foot
  7. Base-plate/Foundations - Structural Looseness, Twisted Supports
  8. Motor insulation - Insulation breakdown

 If I've missed any other common faults, please take a bit of time to add them in as a comment below.

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Steven McFadyen's avatar Steven McFadyen

Steven has over twenty five years experience working on some of the largest construction projects. He has a deep technical understanding of electrical engineering and is keen to share this knowledge. About the author

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  1. Rajeevankeeran's avatar Rajeevankeeran says:
    12/28/2011 7:38 AM

    While it may not be a major problem in Low Voltage Motors, bearing damage due to circulating currents needs special mention. With Regards and wishing all a Happy New Year.

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