Vibration monitoring is perhaps the most beneficial test for rotating machines for identifying mechanical and electrical problems.

Vibration analysis can monitor many mechanical abnormalities among them being wear, imbalance, misalignment, mechanical looseness, bearing damage, bent shaft, structural resonance, fatigue, etc.

Electrical problems reflected in vibration spectra include machine out of magnetic center (uneven air gap, rotor not round or bent rotor, rotor and stator misaligned, elliptical stator bore), loose connectors, open or shorted stator windings, and rotor bar irregularities or broken rotor bars.