A rotor rated flux test or high-current excitation test, often performed with a core tester acting as the power source, can be administered with some degree of success for detection of major rotor bar defects. During a high-current test, an infrared thermal imaging camera is utilized to locate hot spots which indicate broken/damaged rotor bars.
The rotor rated flux test is performed with extremely high current which presents a degree of safety concern for the technician. In addition, this test method subjects the rotor to those same high currents, which could be damaging to the rotor laminations. Finally, the high-current test is difficult to document, report, and doesn’t provide automated evaluation of the test results.