United States Nuclear Regulatory Commission - Protecting People and the Environment

LICENSEE: CONSOLIDATED EDISON CO. OF N.Y./NEW
SITE: INDIAN POINT 2 EN NUMBER: 34836
DOCKET: 05000247 EVENT DATE: 09-25-98
RX TYPE: PWR EVENT TIME: 00:00
VENDORS: W-4-LP NOTIFY DATE: 09-25-98
EMERGENCY CLASS: N/A REGION: 1 STATE: NY TIME: 16:19
OPS OFFICER: BOB STRANSKY
10 CFR SECTION: CCCC 21.21 UNSPECIFIED PARAGRAPH
UNIT SCRAM CODE RX CRIT INIT PWR INITIAL MODE CURR PWR CURRENT MODE
2 N Y 100 POWER OPERATION 100 POWER OPERATION

10 CFR PART 21 REPORT REGARDING WESTINGHOUSE DB-75 CIRCUIT BREAKERS

THE FOLLOWING IS TEXT OF A FACSIMILE SUBMITTED BY THE LICENSEE:

"ON 07/21/98, DURING THE PERFORMANCE OF THE EMERGENCY DIESEL GENERATOR (EDG) LOAD TEST, THE WESTINGHOUSE MODEL DB-75 OUTPUT BREAKER EDG-2053-005 (SERIAL #880.715-3), WHICH CONNECTS THE EDG TO ITS 480 VAC BUS, WOULD NOT CLOSE. A SECOND ATTEMPT WAS MADE TO CLOSE THE BREAKER, AND AGAIN THE BREAKER DID NOT CLOSE. THE BREAKER WAS REMOVED AND THEREAFTER EXAMINED USING HIGH-SPEED PHOTOGRAPHY. IT WAS OBSERVED THAT THE TRIP BAR OPERATION WAS HANGING UP. THE EXACT CAUSE OF THE TRIP BAR MALFUNCTION WAS NOT INITIALLY IDENTIFIED SO THE MECHANISM WAS REMOVED. DURING FURTHER INVESTIGATION, THE TRIP BAR LATCH AND TRIGGER WERE FOUND TO BIND ON OCCASION DUE TO ROUGH EDGES ON THE FACES. COMPARISONS WERE MADE TO OTHER BREAKER MECHANISMS, AND THESE MECHANISMS COULD NOT BE MADE TO HANG UP IN THIS AREA."

"DURING THE INSPECTIONS OF THE REMAINING DB-75 BREAKERS, ONE ADDITIONAL BREAKER WAS FOUND TO EXHIBIT THE SAME BINDING PROBLEM. THIS WAS EDG BREAKER 2053-006 (SERIAL #880.715-1). THIS BREAKER WAS OF THE SAME SERIES AS THE OTHER BREAKER, WHICH MAY INDICATE A MANUFACTURER'S DEFECT. ANOTHER BREAKER IN THE SAME SERIES WAS EXAMINED BUT DID NOT EXHIBIT THE SAME PROBLEM."


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