Pete,
This event goes back to sometime in the 90's.
Details are a bit sketchy.
I do recall that I was at a seminar presented by Baldor and sat next to a PhD. (who's name escapes me) who was responsible for plant engineering of all M&M Mars Candy. Sitting across the table was the speaker from Baldor. About mid-way thru lunch the gentleman from Mars brought up the subject of the multitude of bearing failures they had and were experiencing with Baldor's Premium Efficient motors. We learned that the previous generation of Baldor motors did not have this problem .... and as they eventually ran their inventory down and re-ordered, could no longer obtain the older motor designs as everything had to be Premium Efficient as dictated by D.O.E.
I know they got TVA involved in doing a study ..... I also don't think it was a temperature issue as they did not see a rise in temperature until the bearings were observed to be in failure mode.
I do know that the rep. from Baldor had no answer ... and tried to tap-dance away from it. The gentleman from Mars Candy though was very upset as it was costing the company a lot of money; not only in lost production but in having to trouble shoot and investigate the problem and purchase replacements.
About a week later, I happened to be at another motor manufacturer's facility and one of their engineers held a high position within the NEMA MG-1 committee. I mentioned the Mars Candy problem, and he immediately stated that the cause was due to the motors operating in saturation, which, he said, was how the Baldor motors were able to meet the new Premium Efficiency numbers without having to invest a lot of money in R & D ...
That's it, Pete .... reached the end of the memory bank.....
Cheers.
