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The query [[Category:ENS Notification]] [[Site::Crystal River]] [[Scram::+]] was answered by the SMWSQLStore3 in 0.2241 seconds.


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 Entered dateSiteRegionScramReactor typeEvent description
ENS 4528624 August 2009 12:48:00Crystal RiverNRC Region 2Manual ScramB&W-L-LPFollowing completion of surveillance testing for the electrical checks of the Control Rod Drive power train, the operating crew observed that Group 7 regulating control rods unexpectedly lost power and inserted into the core. The Operators manually tripped the reactor prior to exceeding any RPS trip set point. There were no other safety system actuations and the plant is stable at normal post-trip temperature and pressure. There are seven rods in Group 7. Operators tripped the unit within 7 seconds. All rods fully inserted on the trip. The plant is removing decay heat through the main condenser and feeding generators with auxiliary feed. The licensee notified the NRC Resident Inspector.
ENS 4480727 January 2009 12:41:00Crystal RiverNRC Region 2Manual ScramB&W-L-LPCalibrations of the 'A' Unit 4160V Switchgear metering were in progress when the 'A' Unit 4160V Bus tripped. This resulted in the loss of the 'A' Feedwater Booster Pump (FWBP) and 'A' Condensate Pump (CDP). The Operating crew identified the loss of the 'A' FWBP with increasing RCS pressure and manually tripped the reactor. There were no other safety system actuations and the plant is stable at normal post-trip temperature and pressure. All rods inserted during the trip. Decay heat is being removed via steam dumps to the condenser. The electrical grid is stable with plant loads being supplied by offsite power via the startup transformer. Both vital busses are being powered from offsite. During the transient, main steam relief valves did lift but have been reseated. The NRC Resident Inspector has been notified.
ENS 4443824 August 2008 18:03:00Crystal RiverNRC Region 2Manual ScramB&W-L-LPThe 'A' Condensate Pump became uncoupled, lowering Condensate flow. Operators began to manually lower reactor power to maintain deaerator level. Reactor power was lowered to approximately 62 percent. At this power, (feedwater) flow oscillations began and were excessive. With these flow oscillations increasing the decision was made to manually trip the Reactor. The Reactor was manually tripped at 1557 hours. There were no safety system actuations other than RPS (Manual). The plant is stable in a normal post trip configuration. All control rods inserted into the core during the reactor trip. Offsite power is available and powering safety loads. The steam generator safeties lifted during the transient and reseated. There is no known primary to secondary leakage. Decay heat is being removed via steam dumps to the condenser using normal feedwater to the steam generator. The emergency feedwater system was not initiated during the reactor trip. The licensee notified the NRC Resident Inspector.
ENS 4317921 February 2007 22:11:00Crystal RiverNRC Region 2Automatic ScramB&W-L-LPAt 1915 on February 21, 2007, Crystal River Unit 3 was at reduced power (71%) for planned maintenance on one of four condenser waterboxes when the Integrated Control System (ICS) for Main Feedwater became erratic causing a feedwater transient that underfed the once thru steam generators. The reactor protection system (RPS) actuated on high Reactor Coolant System pressure causing a reactor trip. CR3 also received an Emergency Feedwater Actuation (EFIC) on low steam generator levels. This event is reportable as a 4-Hour Non-Emergency Notification per 10CFR50.72 (b)(2)(iv)(B) for Reactor Protection System Actuation and as an 8-Hour Non-Emergency Notification per 10CFR50.72 (b)(3)(iv)(A) for Emergency Feedwater Actuation and for Reactor Protection System actuation. All systems responded as designed and the plant remains stable with Emergency Feedwater in MODE 3. The licensee informed the NRC Resident Inspector.
ENS 4209429 October 2005 04:39:00Crystal RiverNRC Region 2Manual ScramB&W-L-LPThis event is reportable under 10 CFR 50.72 (b)(2)(iv)(B) and 10 CFR 50.72 (b)(3)(iv)(B)(6). During a plant shutdown for a refueling outage at 0126 (EDT) on October 29, a manual reactor trip was initiated in anticipation of Critical Operation on Emergency Feedwater. CR3 (Crystal River Unit 3) experienced an automatic Emergency Feedwater Actuation based upon a loss of both Main Feedwater Pumps. Main Feedwater Pumps tripped on a loss of the running Main Feedwater Booster Pump, which was automatically tripped on low Feedwater De-aerator Tank level. The redundant Main Feedwater Booster Pump was shutdown as part of the plant shutdown sequence. The low Feedwater De-aerator Tank level occurred due to a loss of the operating Condensate Pump while the redundant Condensate Pump was tagged out of service for scheduled maintenance. The cause of the failed condensate pump that initiated the event sequence is still under investigation but the licensee indicated that it appears to be due to a mechanical failure. The licensee notified the NRC Resident Inspector.
ENS 410236 September 2004 12:44:00Crystal RiverNRC Region 2Automatic ScramB&W-L-LPAt approximately 1150 (EDT), CR3 Site experienced a 230KV 'B' Buss loss. The resultant loss of power was a loss of both non-vital 4160V busses. All RCPs tripped and a reactor trip occurred. The plant is stable on natural circulation cooling. This report is based on the Reactor Protection System Actuation and Specified System Actuation (Emergency Feedwater). The "B" ESF 4160KV Bus deenergized resulting in an autostart of the "B" EDG, as expected. Natural Circulation has been confirmed with both Steam Generators (SGs) receiving Emergency Feedwater (EFW) via both the Turbine-Driven and Diesel-Driven EFW Pumps. The SGs are using the Atmospheric Dumps to remove decay heat. There was no known SG tube leakage prior to the transient. The cause for the partial loss of offsite power is under investigation. The licensee informed the NRC Resident Inspector.
ENS 4060824 March 2004 04:39:00Crystal RiverNRC Region 2Automatic ScramB&W-L-LPAt approximately 0331 EST the reactor tripped due to reactor protection system actuation. The Emergency Feedwater System actuated. It appears that a main feedwater perturbation (sensed low feedwater flow) occurred which actuated a main turbine trip. The main turbine trip actuated the reactor protection system which tripped the reactor. The reactor shutdown and all control rods fully inserted. Decay heat is being removed using the turbine bypass valves and emergency feedwater. The Licensee notified the NRC Resident Inspector.
ENS 402995 November 2003 19:31:00Crystal RiverNRC Region 2Automatic ScramB&W-L-LPCrystal River Unit 3 was at 37 percent power starting up from a refueling outage. During troubleshooting of control problems with the B Main Feedwater Pump, a feedwater transient occurred which underfed the steam generators. This resulted in a reactor trip on high Reactor Coolant System pressure and Emergency Feedwater Actuation on low steam generator levels. This event is reportable as a 4-Hour Non-Emergency Notification per 10CFR50.72 (b)(2)(iv)(B) for Reactor Protection System Actuation and as an 8-Hour Non Emergency Notification per 10CFR50.72 (b)(3)(iv)(A) for Emergency Feedwater Actuation. The licensee reported that all control rods fully inserted on the trip and that steam generator safety valves lifted and reseated as expected. The primary system is currently at 2155 psi, 549 degrees F with steam generator feedwater being supplied by auxiliary feedwater. The main condenser is available and is being used for primary system heat removal via steam dump. The station electrical grid is stable and in normal configuration; the emergency diesel generators are operable and in standby. The licensee has notified the NRC Resident Inspector.