Large induction motor anti-friction bearing selection

The majority of motor specifications utilize L₁₀ life as the sole selection criterion for anti-friction bearings. At times, L ₁₀ lives in excess of 100,000 hours are specified in an attempt to prevent recurring field problems when the failures are originating from nonL₁₀ mechanisms. In some cases, these failures occur indirectly from overspecifying L₁₀ life. Some general examples of this occurence are described. A successful bearing design requires the consideration of many equally important factors, which are discussed in this article