Transient fracture is the main performance index of precision conductive slip ring. It has the characteristics of low occurrenceprobability，short timeanddifficult todetect. However，it iseasy tocauseuncertain impact on the system， which directly related to the reliability of system signal transmission. In this paper，the cause of attitude jump during the modulation of inertial navigation equipment turntable is analyzed. The instantaneous breaking phenomenon of the conductiveslipringisrepeatedbythedetectionsystem，anditpoints outthatsmallforeign matterenteringtheringgroove willinevitablylead tothetransientbreakingphenomenonoftheconductiveslipringwiththecharacteristicsofsymmetrical doublecontactofbrushwireandirreversibledamageoftheconductiveslipring.