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On January 27, 2007, at approximately 1600 … On January 27, 2007, at approximately 1600 EDT, while performing a periodic surveillance of breaker alignment, the Emergency Bus 1 (El) to E3 cross-tie breaker, located on El, was found with the racking lever misaligned slightly from the required vertical position, and the trip pushbutton was found to be depressed (i.e., not flush with the breaker cover as required). The El cross-tie breaker and the E3 cross-tie breaker are two breakers in series between emergency buses El and E3 and allow cross-tying of the two buses during emergency conditions. Control power to the cross-tie breaker is supplied via a local manual switch and is used for Station Black Out (SBO), Fire (i.e., as directed by Alternate Safe Shutdown (ASSD)), and maintenance procedures. The breaker was determined to be racked-in past the normal connected position and would have prevented closure of the breaker.</br></br>This event is being reported in accordance with 10 CFR 50.73(a)(2)(ii)(B), as an event or condition that resulted in the plant being in an unanalyzed condition that significantly degraded plant safety. It appears that the breaker was in the tripped condition since April 29, 2006, the date of the last documented activity affecting this breaker.</br></br>The select cause of this event is a failure to properly rack-in the breaker in accordance with procedure 10P-50, "Plant Electric System Operating Procedure.Plant Electric System Operating Procedure. +
January 27, 2007 +
On January 27, 2007, at approximately 1600 … On January 27, 2007, at approximately 1600 EDT, while performing a periodic surveillance of breaker alignment, the Emergency Bus 1 (El) to E3 cross-tie breaker, located on El, was found with the racking lever misaligned slightly from the required vertical position, and the trip pushbutton was found to be depressed (i.e., not flush with the breaker cover as required). The El cross-tie breaker and the E3 cross-tie breaker are two breakers in series between emergency buses El and E3 and allow cross-tying of the two buses during emergency conditions. Control power to the cross-tie breaker is supplied via a local manual switch and is used for Station Black Out (SBO), Fire (i.e., as directed by Alternate Safe Shutdown (ASSD)), and maintenance procedures. The breaker was determined to be racked-in past the normal connected position and would have prevented closure of the breaker.</br></br>This event is being reported in accordance with 10 CFR 50.73(a)(2)(ii)(B), as an event or condition that resulted in the plant being in an unanalyzed condition that significantly degraded plant safety. It appears that the breaker was in the tripped condition since April 29, 2006, the date of the last documented activity affecting this breaker.</br></br>The select cause of this event is a failure to properly rack-in the breaker in accordance with procedure 10P-50, "Plant Electric System Operating Procedure.Plant Electric System Operating Procedure. +
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March 27, 2007 +
January 27, 2007 +
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