Which of the following is a limitation of Motor Current Signature analysis?

Motor Current Signature Analysis (MCSA) is a technique used to assess the health of electric motors by analyzing the current waveforms they produce. A notable limitation of this analysis method is the lack of voltage as a reference, which can indeed lead to misleading interpretations of harmonic content within the motor's operation.

When voltage is not measured directly, it becomes challenging to accurately determine the harmonic distortions affecting current. Harmonics can indicate various issues such as imbalance, mechanical faults, or electrical problems. Without the voltage data, discerning the actual nature and source of these harmonics becomes difficult, leading to potential misdiagnosis of the motor's condition.

This aspect highlights the inherent complexity in the analysis of motor health using just current data. Prioritizing voltage measurements alongside current readings would provide a more comprehensive picture of motor performance and health, making the analysis more effective.

The other options present attributes or restrictions of MCSA that do not inherently represent limitations. For instance, the capability to analyze multiple phases simultaneously is a strength of the technique, while the requirement for direct contact is not inherent to MCSA itself. Furthermore, while the tool's application is broad, it is not restricted solely to synchronous motors, making the concern for specific motor types less relevant in terms of limitations