A system and method for detection of a fault in a component of an Alternate Current Motor (ACM) based on current samples of the ACM. The system includes a current sensor for sampling a current of the ACM. The sampling is performed a plurality of times within a half-wave form of an Alternate Current (AC) of the ACM and over several cycles of half-waves. The system also includes a computing device for receiving the plurality of current samples. The computing device is configured to analyze a plurality of current samples of the AC of the ACM, the plurality of current samples taken for at least several periods of half-waves of the AC, determine, based on the analysis of the plurality of current samples, whether the ACM is a Variable Frequency Drive (VFD) or a non-VFD, and report that fault detection cannot be made if the ACM is a VFD.