What fault condition can be identified by motor current analysis?

Motor current analysis is a valuable diagnostic tool that focuses on the electrical characteristics of the motor, particularly the current flowing through the windings. This technique effectively identifies various fault conditions based on how the motor operates under different load and fault scenarios.

Broken rotor bars are one of the faults that can be detected through analysis of the motor current. When rotor bars are broken, it causes an imbalance in the electromagnetic forces generated in the motor, which can result in abnormal current signatures. Specifically, the current drawn by the motor may exhibit specific patterns, such as increased harmonic content and variations in the amplitude of the current waveform, which are indicative of rotor bar problems. These patterns reflect the motor struggling to maintain operational efficiency due to the breakdown in rotor functionality.

Other options, such as insulation breakdown or winding contamination, might show symptoms in different parameters, but they would not primarily manifest themselves through current analysis alone. Leakage currents, similarly, pertain more to insulation faults and are usually assessed with tests that measure voltage and insulation integrity rather than looking exclusively at motor current profiles. Thus, broken rotor bars are clearly identifiable by observing the characteristics of the motor's current, making it the correct choice for this question.