Information Sheet #8 - Electric Motor Vibration Definitions and Sources Within a Motor.
1.0 Introduction:
An electric motor is a rotating electro mechanical piece of equipment. As for all moving pieces of equipment the rotating mass is a sum of all its parts, if any of those parts create an out of balance force vibration will occur. While all rotating machinery creates some level of vibration, if vibration exceeds designed limitations it will lead to failure. It is important to understand what is vibration and how it effects an electric motor. Users that understand the significance of vibration on their equipment ensure testing for vibration is part of any planned maintenance program.
2.0 Definition of Vibration:
Vibration is a mechanical phenomenon whereby oscillations occur about an equilibrium point. The word comes from Latin vibrationem. The oscillations may be periodic, such as the motion of a pendulum, or random, such as the movement of a tire on a gravel road. Vibration in an electric motor is simply a back and forth movement, or oscillation, of the total motor and components incorporated into the motor. Individual vibration signals combine to form a complex time waveform showing overall vibration.