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And the radial force on the rotor bearing is apparently the culprit.
I had two such failures recently. Motors that have a duty factor less than 1%. Used to accelerate a high inertia load by a factor of 5 in rpm.
Phil Corso suggested that I put up this information along with the succesful application of his broken rotor bar test.
An AM radio was tuned to a dead part of the band and the antenna placed 1 inch from the motor case. Indeed, when near motor rpm was reached, a crackle could be heard every second or two, indicating arcing in a rotor bar.
The crackle dissapeared when the motor went off line.
I had two such failures recently. Motors that have a duty factor less than 1%. Used to accelerate a high inertia load by a factor of 5 in rpm.
Phil Corso suggested that I put up this information along with the succesful application of his broken rotor bar test.
An AM radio was tuned to a dead part of the band and the antenna placed 1 inch from the motor case. Indeed, when near motor rpm was reached, a crackle could be heard every second or two, indicating arcing in a rotor bar.
The crackle dissapeared when the motor went off line.
