Diagnosing Rotor Bar Issues with Torque and Current Signature Analysis
Over the years rotor bar problems have been a diagnostic challenge for motor maintenance professionals. Now with current signature, spectral torque analysis and automated computer diagnostic software, defining rotor health problems has been made fairly simple. However, problems arise when professionals Do not understand the underlying principles of the whats, whys and hows of dynamic rotor testing. Individuals need to be able to answer the following questions. How can an instrument 100 - 1,000 feet or more away from the motor provide information about the condition of the rotor? What are the effects going on within the motor to produce the peaks and ripples that we see? What defines the frequencies of the peaks and causes the amplitude to increase as the rotor bars break? And finally, how do we interpret those signals to make proactive decisions about motor repair scheduling?