Motor Current Signature Analysis in Predictive Maintenance

Abstract

The aim of this paper is to draw attention to the possibilities offered by spectral analysis of current and voltage in the predictive maintenance of the electric motor. Motor Circuit analysis (MCA) and Motor Current Signature analysis (MCSA) are innovative and non-invasive methods that enable diagnostics and assessment of the condition of the electric motor. The main advantage of the method is that the test is carried out during the normal motor operation, without downtime. All motor defects can be detected at the earliest stage. This enable planning the overhaul according to the condition which can make significant savings. Advanced MCSA analysers enable diagnostics of electric motors that are powered either via a soft starter, frequency inverter or directly from mains. So, it is possible in a simple and reliable way make an condition assessment of frequency inverters. In addition, it is possible to detect faults of driven machine, like misalignment, imbalance, blade faults, belts, bearings issues etc. Theoretical basis and tests that are carried out are explained in the paper.