8 Motor parts and common faults 

By on

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.



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

myElectrical Engineering

comments powered by Disqus

  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.


Comments are closed for this post:
  • have a question or need help, please use our Questions Section
  • spotted an error or have additional info that you think should be in this post, feel free to Contact Us



How to Size Current Transformers

The correct sizing of current transformers is required to ensure satisfactory operation of measuring instruments and protection relays. Several methods...

Wiki Depreciation

We have had the Wiki with us for a long time now, but at last I have decided to say bye bye – more details on why below.

Maxwell's Equations - Introduction

Maxwell's Equations are a set of fundamental relationships, which govern how electric and magnetic fields interact. The equations explain how these fields...

Understanding electric motor insulation & temperature

Anyone specifying or using electric motors should have a basic understanding how the insulation is related to temperature. Three classes of insulation...

Induction Motor Calculator

Just added a page to the tools, which will allow you to calculate the synchronous speed, slip and rated torque for an induction motor. Not a particularly...

Why a Sine Wave?

I received this question by email a few weeks. First thoughts was that it is a product of the mathematics of rotating a straight conductor in a magnetic...

Tips for a better Low Voltage Protection Discrimination Study

Carrying out a protection system discrimination study is critical to ensure the correct functioning of  the electrical system in the event of faults. ...

DC Component of Asymmetrical Faults

The image (reproduced from IEC 60909) shows a typical fault in an ac system.  From the illustration it can seen that there is an initial dc component ...

Welcome back Bottle

‘Kept looking at a card, y’see? Kept looking at it. Welcome back Bottle. Gods below welcome home. The Crippled God A Tale of the Malazan Book of the...

Dielectric loss in cables

Dielectrics (insulating materials for example) when subjected to a varying electric field, will have some energy loss.   The varying electric field causes...

Have some knowledge to share

If you have some expert knowledge or experience, why not consider sharing this with our community.  

By writing an electrical note, you will be educating our users and at the same time promoting your expertise within the engineering community.

To get started and understand our policy, you can read our How to Write an Electrical Note