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U.S. Department of Energy
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Bearing monitor anticipates failures. [Electric generators and motors]

Journal Article · · Electr. Light Power (Boston); (United States)
OSTI ID:7343998

Electromagnetic asymmetry exists to some extent in all large generators and electric motors. This phenomenon can produce a shaft voltage to cause a current flow that, if left unchecked, can arc across the protective oil film at the bearing to pit the surface. Continued arcing leads to bearing failure. A new monitoring system which can detect a breakdown in the internal insulation that protects the bearing area is described. Tests prove that the capacitive voltage across the oil film can be analyzed to indicate the condition of the bearing insulation without bridging that insulation. The monitoring system continuously measures this voltage and compares it to values taken when the insulation was known to be in good condition. Visual indications of deterioration or breakdown are included on the monitor. The monitoring system has performed satisfactorily since installed in May 1975. (LCL)

OSTI ID:
7343998
Journal Information:
Electr. Light Power (Boston); (United States), Journal Name: Electr. Light Power (Boston); (United States) Vol. 54:3; ISSN ELLPA
Country of Publication:
United States
Language:
English