2 février 2014
La pompe de secours s’était bien enclenchée pour prendre le relais de la pompe défaillante mais l’indication de son fonctionnement ne s’est pas affichée sur le voyant témoin. Le cœur étant critique, les systèmes de protection du réacteur se sont enclenchés. L’arrêt du réacteur se serait effectué correctement.
Type : PWR - Puissance thermique : 2 940 MWTh - Première divergence : 06 / 1980
Available in english only.
Event Number : 49784 - Facility : NORTH ANNA - State : VA - Unit : [2] RX Type : [2] W-3-LP
Event Date : 02/02/2014 - Event Time : 08:59 -
Emergency Class : NON EMERGENCY 10 CFR Section : 50.72(b)(2)(iv)(B) - RPS ACTUATION - CRITICAL 50.72(b)(3)(iv)(A) - VALID SPECIF SYS ACTUATION
Initial PWR : 100 % Current PWR 0 %
Event Text
MANUAL REACTOR TRIP FOLLOWING LOSS OF THE "A" MAIN FEEDWATER PUMP
"On 2-2-2014 at 0859 [EST], with Unit 2 operating at 100% power, a manual reactor trip was initiated by the control room staff following a trip of the ’A’ main feedwater pump and automatic start of the ’C’ feedwater pump due to crew concerns that both motors of the ’C’ feedwater pump had not actuated. When the ’C’ feedwater pump auto started, the running indicator light for one of the ’C’ feedwater pump motors failed to illuminate. Both motors of the ’C’ feedwater pump had started as designed. Following the reactor trip, all control rods fully inserted into the core and Unit 2 was stabilized in Mode 3 at normal reactor coolant system temperature and pressure. Decay heat is being removed using the normal condenser steam dump system. Unit 2 is in a normal shutdown electrical alignment with power being supplied from the Reserve Station Service Transformers. This event is reportable per 10CFR50.72(b)(2)(iv)(B) for actuation of the reactor protection system.
"Following the reactor trip, the auxiliary feedwater pumps automatically started as designed and provided makeup flow to the steam generators. The steam generator levels were returned to normal operating level and the auxiliary feedwater pumps were returned to the normal standby automatic alignment. This event is reportable per 10CFR50.72(b)(3)(iv)(A) for actuation of an ESF system.
"Unit 1 is operating at 100% power and was not affected by the event."
https://www.nrc.gov/reading-rm/doc-collections/event-status/event/2014/20140203en.html