Electric Motors Condition Monitoring Using Currents and Vibrations Analyses

The article discusses how the electric motor and coupled machine design and malfunction behavior is reflected in the current spectrum using Motor Current Signature Analysis and in the vibration spectrum using Vibration Analysis. The paper further describes the results of tests and diagnostics of Squirrel Cage Induction Motor malfunctions such as unbalance, misalignment, looseness, broken rotor bars and bearing damage using both techniques. A commercial device able to apply both types of technologies is employed in the work. The article contrasts the similarities vs. differences and advantages vs. disadvantages of both methods and may be of value for field engineers to understand the pros and cons of each technology.