Part 21 Report - 1996-820

LICENSEE: WESTINGHOUSE ELECTRIC CORPORATION SITE: WESTINGHOUSE ELECTRIC CORPORAT EN NUMBER:31449 DOCKET: EVENT DATE: 12-13-96 RX TYPE: EVENT TIME: 00:00 VENDORS: NOTIFY DATE: 12-13-96 EMERGENCY CLASS: N/A REGION: 1 STATE: PA TIME: 14:22 OPS OFFICER: LEIGH TROCINE 10 CFR SECTION: CCCC 21.21 UNSPECIFIED PARAGRAPH MOLDED CASE CIRCUIT BREAKERS WITH INCORRECTLY INSTALLED DC SHUNT TRIP UNITS AND MISSING SHUNT TRIP BARRIERS CALLAWAY IDENTIFIED A DEVIATION DURING TESTING OF 6 TYPE HFD3045 AND HFD3060 MOLDED CASE CIRCUIT BREAKERS WITH 125-VOLT DC SHUNT TRIP DEVICES SUPPLIED AS SAFETY-RELATED BY WESTINGHOUSE. THE SHUNT TRIP CIRCUITRY IS SPECIFIED TO BE EQUIPPED WITH A CUT-OFF SWITCH TO REMOVE THE SHUNT TRIP COIL FROM THE POWER SOURCE SUBSEQUENT TO TRIPPING THE BREAKER. THE COIL IS NOT DESIGNED FOR CONTINUOUS DUTY AND WOULD EVENTUALLY OPEN THE CIRCUIT IF IT REMAINED ENERGIZED. THE SHUNT TRIP COIL OF THE BREAKERS SUPPLIED TO CALLAWAY REMAINED CONNECTED TO THE POWER SOURCE AFTER THE BREAKER TRIPPED. IN ADDITION, DURING THE EVALUATION OF THE BREAKERS THAT WERE RETURNED FROM CALLAWAY, IT WAS DETERMINED THAT SHUNT TRIP BARRIERS WERE MISSING. THESE BARRIERS PROVIDE PROTECTION AGAINST DAMAGE DUE TO ARCING. THE VENDOR (CUTLER HAMMER) DETERMINED THAT 21 BREAKERS WITH EITHER AC OR DC SHUNT TRIP UNITS (INCLUDING THE 6 REFERENCED ABOVE) HAD BEEN SHIPPED ONLY TO THE CALLAWAY PLANT. SUBSEQUENT OPERABILITY OF THESE BREAKERS AFTER A TRIP HAS NOT YET BEEN DETERMINED BY CUTLER HAMMER. ALL SIX OF THE BREAKERS WITH INCORRECTLY INSTALLED DC SHUNT TRIP UNITS HAVE BEEN IDENTIFIED AND ARE IN THE PROCESS OF BEING RETURNED TO THE VENDOR. WESTINGHOUSE HAS ALSO BEEN INFORMED BY CALLAWAY THAT ONLY ONE BREAKER WITH A SUSPECT BARRIER IS IN SERVICE. CALLAWAY DOES NOT PLAN TO PLACE THE REMAINING FOURTEEN BREAKERS IN SERVICE UNTIL IT IS VERIFIED THAT THE SHUNT TRIP BARRIERS ARE INSTALLED. SINCE SUBSEQUENT OPERABILITY OF THE SHUNT TRIP UNITS WITH MISSING BARRIERS IS INDETERMINATE, CALLAWAY WILL BE ADVISED TO PERFORM A SURVEILLANCE TEST AFTER ANY BREAKER TRIP DEMAND UNTIL THE BREAKER CAN BE CORRECTED OR REPLACED.

Page Last Reviewed/Updated Friday, January 31, 2020