Study on electric motor mass unbalance based on vibration monitoring analysis technique

This paper presents the effective method to carry out troubleshooting for electric motor mass unbalance problem based on vibration analysis. Vibration can be used to identify defects that arise from defective design, faulty installation, and wear and tear. In this paper, velocity used for measurement which relates to components fatigue based on time rate of machine motion. Besides that, frequencies measured on the bearing caps and shafts of a machine are used to conduct fault diagnosis. These vibrations are caused (excited) by vibratory forces (excitations). In general, the frequency of the measured vibration is the same as that of the force causing the vibration. The operating speed of the machine is the reference frequency for diagnostic techniques. A multiple of operating speed (order) implies that a vibration arises as a result of machine operation. Motor vibration problem such as mass unbalance will be detected using spectrum analysis where the frequencies acquired from shaft displacement and casing-mounted transducers are related to the known frequencies of the machine. Field or shop balancing will be carried out if mass unbalance problem occurs to the electric motor.