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On March 11, 2001, at 0109 hours, with Uni … On March 11, 2001, at 0109 hours, with Unit 2 at 0 percent power (Mode 3) and shutting down for refueling, the control bank "B" group 2 step counter demand position indicator stopped moving at 53 steps. The Limiting Condition for Operation (LCO) for Technical Specification 3.1.3.3 requires the rod group step counter demand position indicator to be within plus or minus 2 steps of the demand position from the logic cabinet for each shutdown or control rod group not fully inserted. The control bank "B" group 2 step counter demand position indicator was greater than 2 steps from the demand position from the logic cabinet. The action requirements of TS 3.1.3.3 require the reactor trip breakers to be opened within 15 minutes if the LCO requirements cannot be met. At 0119 hours, a manual reactor trip was initiated by opening the reactor trip breakers. At 0428 hours, an 8 hour report was made to the NRC Operations Center in accordance with 10 CFR 50.72(b)(3)(iv)(A). The cause for the control bank "B" group 2 step counter demand position indicator not moving was determined to be a defect in the down counter gear. This event is reportable per 10 CFR 50.73 (a)(2)(iv)(A) for any event or condition that resulted in the manual actuation of the reactor protection system. No significant safety consequences resulted from this event since the reactor was already subcritical, with the control banks fully inserted, when the reactor trip breakers were opened and the shutdown banks inserted into the core. Therefore, the health and safety of the public were not affected at any time during this event.ot affected at any time during this event. +
March 11, 2001 +
On March 11, 2001, at 0109 hours, with Uni … On March 11, 2001, at 0109 hours, with Unit 2 at 0 percent power (Mode 3) and shutting down for refueling, the control bank "B" group 2 step counter demand position indicator stopped moving at 53 steps. The Limiting Condition for Operation (LCO) for Technical Specification 3.1.3.3 requires the rod group step counter demand position indicator to be within plus or minus 2 steps of the demand position from the logic cabinet for each shutdown or control rod group not fully inserted. The control bank "B" group 2 step counter demand position indicator was greater than 2 steps from the demand position from the logic cabinet. The action requirements of TS 3.1.3.3 require the reactor trip breakers to be opened within 15 minutes if the LCO requirements cannot be met. At 0119 hours, a manual reactor trip was initiated by opening the reactor trip breakers. At 0428 hours, an 8 hour report was made to the NRC Operations Center in accordance with 10 CFR 50.72(b)(3)(iv)(A). The cause for the control bank "B" group 2 step counter demand position indicator not moving was determined to be a defect in the down counter gear. This event is reportable per 10 CFR 50.73 (a)(2)(iv)(A) for any event or condition that resulted in the manual actuation of the reactor protection system. No significant safety consequences resulted from this event since the reactor was already subcritical, with the control banks fully inserted, when the reactor trip breakers were opened and the shutdown banks inserted into the core. Therefore, the health and safety of the public were not affected at any time during this event.ot affected at any time during this event. +
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April 24, 2001 +
March 11, 2001 +
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