ENS 42505
ENS Event | |
---|---|
21:15 Apr 15, 2006 | |
Title | Reactor Scram from 100% Power |
Event Description | At 1615 CDT time on April 15th, 2006 with the Reactor at 100% power, River Bend Station experienced a reactor scram resulting from a RPS actuation. All plant systems performed as designed. The reactor is stable with pressure and temperature being controlled by feed water system and main steam bypass valves, respectively. The cause of the scram is not known at this time. The plant is conducting causal investigations to fully understand the cause of the plant scram.
All control rods fully inserted, no safety valves lifted, and no Emergency Safety Feature actuations occurred on the scram. The electrical grid is stable. The licensee notified the NRC Resident Inspector.
River Bend Station status on 04/16/2006: The unit is in Mode 3, Hot Shutdown, and stable. Investigation of the plant trip found an optical isolator in the control circuit for the end-of-cycle recirculation pump trip failed causing both recirculation pumps to shift to slow speed. The pump downshift placed reactor power and flow into the exclusion region of the power to flow map. The reactor received trip signals from APRM E & H heat flux exceeding their corresponding trip set points. The optical isolator is being replaced. Plant restart will commence pending successful replacement of the optical isolator. The licensee informed the NRC Resident Inspector. Notified R4DO (Pruett). |
Where | |
---|---|
River Bend ![]() Louisiana (NRC Region 4) | |
Reporting | |
10 CFR 50.72(b)(2)(iv)(B), RPS Actuation | |
Time - Person (Reporting Time:+-0.38 h-0.0158 days <br />-0.00226 weeks <br />-5.20524e-4 months <br />) | |
Opened: | Vernon Carlson 20:52 Apr 15, 2006 |
NRC Officer: | Mark Abramovitz |
Last Updated: | Apr 16, 2006 |
42505 - NRC Website
Loading map... {"minzoom":false,"maxzoom":false,"mappingservice":"leaflet","width":"350px","height":"250px","centre":false,"title":"","label":"","icon":"","lines":[],"polygons":[],"circles":[],"rectangles":[],"copycoords":false,"static":false,"zoom":6,"defzoom":14,"layers":["OpenStreetMap"],"image layers":[],"overlays":[],"resizable":false,"fullscreen":false,"scrollwheelzoom":true,"cluster":false,"clustermaxzoom":20,"clusterzoomonclick":true,"clustermaxradius":80,"clusterspiderfy":true,"geojson":"","clicktarget":"","imageLayers":[],"locations":[{"text":"\u003Cb\u003E\u003Cdiv class=\"mw-parser-output\"\u003E\u003Cp\u003E\u003Ca class=\"mw-selflink selflink\"\u003EENS 42505\u003C/a\u003E - \u003Ca href=\"/River_Bend\" title=\"River Bend\"\u003ERiver Bend\u003C/a\u003E\n\u003C/p\u003E\u003C/div\u003E\u003C/b\u003E\u003Cdiv class=\"mw-parser-output\"\u003E\u003Cp\u003EReactor Scram from 100% Power\n\u003C/p\u003E\u003C/div\u003E","title":"ENS 42505 - River Bend\n","link":"","lat":30.759530555555557,"lon":-91.3300888888889,"icon":"/w/images/7/79/Entergy_icon.png"}],"imageoverlays":null} | |
Unit 1 | |
---|---|
Reactor critical | Critical |
Scram | A/R |
Before | Power Operation (100 %) |
After | Hot Shutdown (0 %) |
WEEKMONTHYEARENS 568872023-12-13T07:02:00013 December 2023 07:02:00
[Table view]10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Scram ENS 568632023-11-18T05:55:00018 November 2023 05:55:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Manual Reactor Scram ENS 551692021-04-02T15:17:0002 April 2021 15:17:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Automatic Reactor Scram Due to Turbine Trip ENS 551542021-03-25T14:18:00025 March 2021 14:18:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Manual Reactor Trip Due to Lowering Condenser Vacuum ENS 548492020-08-21T14:18:00021 August 2020 14:18:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Manual Reactor Scram ENS 540962019-06-01T04:45:0001 June 2019 04:45:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Manual Reactor Scram Due to Low Reactor Water Level ENS 537322018-11-10T05:00:00010 November 2018 05:00:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Automatic Reactor Scram on High Reactor Pressure ENS 531922018-02-01T16:57:0001 February 2018 16:57:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Manual Reactor Scram ENS 529152017-08-19T01:55:00019 August 2017 01:55:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Automatic Scram While at 100 Percent Power ENS 528252017-06-24T01:18:00024 June 2017 01:18:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Automatic Reactor Scram on Main Generator Trip ENS 526022017-03-10T13:14:00010 March 2017 13:14:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Manual Reactor Scram Due to Closure of the Main Turbine Control Valves ENS 516442016-01-09T08:37:0009 January 2016 08:37:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Scram on Main Steam Isolation Due to Electrical Fault ENS 515682015-11-27T10:31:00027 November 2015 10:31:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Scram Following Partial Loss of Offsite Power ENS 511122015-06-02T02:11:0002 June 2015 02:11:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Reactor Scram Due to Low Reactor Water Level ENS 507042014-12-25T14:37:00025 December 2014 14:37:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Scram ENS 505462014-10-17T08:03:00017 October 2014 08:03:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Scram on High Average Power Range Monitor Flux ENS 479602012-05-24T18:48:00024 May 2012 18:48:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation, 10 CFR 50.72(b)(3)(xiii), Loss of Emergency Preparedness Manual Reactor Scram Due to a Loss of Feed as Result of a Loss of Switchgear ENS 479402012-05-21T19:52:00021 May 2012 19:52:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Automatic Reactor Scram Resulting from a Low Condenser Vacuum-Turbine Trip ENS 475492011-12-23T12:10:00023 December 2011 12:10:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Automatic Reactor Scram Due to a Turbine Trip ENS 453692009-09-20T22:47:00020 September 2009 22:47:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Manual Scram Due to Reactor Recirc Pump Trip ENS 440342008-03-05T20:43:0005 March 2008 20:43:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Automatic Scram Due to Apparent Malfunction in Turbine Control System ENS 437732007-11-07T09:06:0007 November 2007 09:06:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation, 10 CFR 50.72(b)(2)(iv)(A), System Actuation - ECCS Discharge Reactor Scram as a Result of Loss of Normal Power 13.8 Kv Bus ENS 436682007-09-27T03:44:00027 September 2007 03:44:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Automatic Reactor Scram During the Performance of Aprm Surveillance Testing ENS 433452007-05-04T17:56:0004 May 2007 17:56:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Manual Reactor Scram Due to Loss of Cooling to Number 2 Main Transformer ENS 429212006-10-19T22:56:00019 October 2006 22:56:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident, 10 CFR 50.72(b)(3)(iv)(A), System Actuation, 10 CFR 50.72(b)(2)(iv)(A), System Actuation - ECCS Discharge Automatic Scram Following Spontaneous Feedwater Valve Closure ENS 425052006-04-15T21:15:00015 April 2006 21:15:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Reactor Scram from 100% Power ENS 413392005-01-15T08:12:00015 January 2005 08:12:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Manual Reactor Scram Due to Receiving a Main Generator Alarm ENS 412522004-12-10T19:17:00010 December 2004 19:17:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Reactor Scram Due to Loss of Vital Instrument Bus ENS 410822004-10-01T12:30:0001 October 2004 12:30:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(2)(iv)(A), System Actuation - ECCS Discharge Reactor Trip Due to Main Generator Load Rejection ENS 409572004-08-15T09:05:00015 August 2004 09:05:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Scram Following Partial Loss of Offsite Power ENS 401912003-09-23T03:43:00023 September 2003 03:43:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Automatic Reactor Scram Received During Main Turbine Control Valve Testing 2023-12-13T07:02:00 | |