Traditional rotor bar defect detection systems are often insufficient in sensitivity, record-ability and numerical analysis of test results. Many means of rotor defect detection require the motor to be fully assembled with a functional stator. These limitations have laid the groundwork for the development of a new rotor defect detection technique.

Being accustomed to rewinding AC stators, we may not realize that there is an equivalent repair service that can be performed on some rotors - namely, rebarring. Our focus in this article will be the rebarring of fabricated copper squirrel cage rotors. Redesign of rotors is outside the scope of this article.

Most EASAns are familiar with the basics of rotor rebarring. We know that the endrings and bars are not always the same material, and understand the importance of maintaining the cage resistance. For those of us who only occasionally rebar rotors, here are a few tips to assure a quality repair.