“…Different techniques that can be used for implementing a CBM system for IMs [19], such as the analysis of currents [20][21][22][23][24], vibrations [24][25][26][27], instantaneous power [28], reactive power [29], apparent power [21], voltages [30,31], back EMFs induced tooth-coil windings [32,33], voltage injection [34], thermal images [35,36], internal flux [37,38], acoustic emissions [39,40], etc. Among these methods, the analysis of the machine current signature (MCSA) method has attracted an special interest [24,41], because it is non invasive (it requires only a current probe that can be attached to the line which feeds the machine), fast an easy to implement online (it uses a FFT to obtain the current spectrum, where the characteristic fault signatures can be detected), and is able to detect different, and possibly simultaneous [42][43][44], types of faults, and it can be operated on line. In spite of its conceptual simplicity, the practical application of MCSA in harsh industrial environments is a challenging issue.…”