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



Earth Electrode Resistance

Earthing of electrical systems is essential for the correct functioning and the protecting of life and equipment in the event of faults.  The earth electrode...

Nikola Tesla

Nikola Tesla was born exactly at midnight on July 10, 1856 in the tiny village of Smiljan, Lika in Croatia. In his late teens, Tesla left the village to...

Getting Started with Patents

If you have a great idea or invent something the last thing you want is someone to steal the idea. One of the things you can do is protect the intellectual...

How to refer fault levels across a transformer

Over the past year or so I've been involved in on going discussions related to referring fault levels from the secondary of a transformer to the primary...

Load Flow Study – how they work

A load flow study is the analysis of an electrical network carried out by an electrical engineer. The purpose is to understand how power flows around...

UPS - Uninterruptible Power Supply

A UPS is an uninterruptible power supply.  It is a device which maintains a continuous supply of electrical power, even in the event of failure of the...

How to Check a Circuit is Dead

If you want to check a circuit is dead (not live), you should always use the three point method. First check a known live circuit, then check the dead...

IEC 61439 Verification Methods

The (relatively new) switchgear and control gear standard, IEC 61439 'Low-voltage switchgear and controlgear assemblies' has three methods which can be...

Skin Tapping Input

Tapping your forearm or hand with a finger could soon be the way you interact with gadgets. A new technology created by Microsoft and Carnegie Mellon ...

Motor Insulation

Insulation on a motor prevents interconnection of windings and the winding to earth.  When looking at motors, it is important to understand how the insulation...

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