A noninvasive diagnostic instrument for power circuit breakers

Abstract

Noninvasive diagnostics, involving short-time spectra, short-time energy, and automatic timing techniques, have been applied to assess the mechanical condition of oil and puffer circuit breakers and to determine the timing of events occurring during operation. A portable instrument that employs these techniques has been developed and tested at various utilities. The capabilities of this instrument and the results of the field trials are presented.