Noise in Motors is a nuisance and a waste of energy. The more efficient a motor, the lesser the noise it produces. However, noise is also an important parameter for diagnosing the condition of a motor. However, a careful analysis of the noise of a motor can given an idea of the condition of the different components of a motor.
Noise analysis can tell about the condition of the bearings. Misalignment of the motor coupling can also given a distinct noise signal
A choked filter for cooling will produce a distinct noise caused by the altered airflow.
Powerful tools such as FFT (Fast Fourier Transforms) help analyze specific frequencies and localize abnormalities, if any.
Technicians and Engineers should be trained to detect abnormality in sound. Noise Analysis of motors in an industry can be carried out at periodic schedules in consultation with the motor manufacturer.