ENS 48722
ENS Event | |
---|---|
17:43 Feb 6, 2013 | |
Title | Unusual Event - Loss of Offsite Power to Essential Buses for Greater than 15 Minutes |
Event Description | At 1132 CST on 2/6/13, Point Beach Unit 1 experienced a loss of all offsite power due to the loss of 1X-03 High Voltage Station Aux Transformer. The high side circuit switcher opened. However, the 1X-03 transformer did not lock out resulting in G-01 and G-03 Emergency Diesels energizing the 1A-05 and 1A-06 4160 VAC busses (safety related).
The cause of the loss of offsite power is being investigated. In order to exit the event, the plant requires either 345 kV power to be restored or cross-tie plant power between the units. If cross-tied, Technical Specifications require the gas turbine to be placed on the cross-tie within 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />. The plant remained at 100% power and there was no effect on Unit 2. The licensee notified the NRC Resident Inspector. Notified the DHS SWO, FEMA, DHS NICC, and the Nuclear SSA (via e-mail).
There were specified system actuations with the original event. Emergency diesel generators [EDG] G-01, 2, 3, and 4 started on the undervoltage conditions with G-01 and G-03 loading onto their respective buses. 1P-53, motor driven aux feed pump started as designed on the EDG breaker closures. Offsite power has been restored to safeguards buses and the EDGs have been removed from the buses. Troubleshooting continues on the initial fault. All other systems functioned as designed. The unusual event has been terminated as of 1340 CST on 2/6/13. The safeguards buses are being powered from Unit 2 through the electrical cross-tie. The licensee notified the NRC Resident Inspector. Notified the R3DO (Kunowsky), NRR EO (Evans), IRD (Marshall), DHS SWO, FEMA, DHS NICC, and the Nuclear SSA (via e-mail). |
Where | |
---|---|
Point Beach ![]() Wisconsin (NRC Region 3) | |
Reporting | |
Emergency class: | Unusual Event |
10 CFR 50.72(a) (1) (i), Emergency Class Declaration 10 CFR 50.72(b)(3)(iv)(A), System Actuation | |
Time - Person (Reporting Time:+-4.27 h-0.178 days <br />-0.0254 weeks <br />-0.00585 months <br />) | |
Opened: | Denny Smith 13:27 Feb 6, 2013 |
NRC Officer: | Mark Abramovitz |
Last Updated: | Feb 6, 2013 |
48722 - 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 48722\u003C/a\u003E - \u003Ca href=\"/Point_Beach\" title=\"Point Beach\"\u003EPoint Beach\u003C/a\u003E\n\u003C/p\u003E\u003C/div\u003E\u003C/b\u003E\u003Cdiv class=\"mw-parser-output\"\u003E\u003Cp\u003EUnusual Event - Loss of Offsite Power to Essential Buses for Greater than 15 Minutes\n\u003C/p\u003E\u003C/div\u003E","title":"ENS 48722 - Point Beach\n","link":"","lat":44.280972222222225,"lon":-87.53674444444445,"icon":"/w/images/9/9b/NextEra_Energy_icon.png"}],"imageoverlays":null} | |
Unit 1 | |
---|---|
Reactor critical | Critical |
Scram | No |
Before | Power Operation (100 %) |
After | Power Operation (100 %) |
Point Beach ![]() | |
WEEKMONTHYEARENS 553902021-07-31T21:46:00031 July 2021 21:46:00
[Table view]10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Manual Reactor Trip of Unit 1 ENS 537792018-12-05T06:00:0005 December 2018 06:00:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Manual Reactor Trip on Loss of Main Condenser Vacuum ENS 530042017-10-09T12:37:0009 October 2017 12:37:00 10 CFR 50.72(a)(1)(i), Emergency Class Declaration Unusual Event Declaration for Toxic Gas Spill ENS 526272017-03-20T21:20:00020 March 2017 21:20:00 10 CFR 50.72(a)(1)(i), Emergency Class Declaration Unusual Event Declared for Fire Alarm in Containment ENS 515702015-11-29T01:12:00029 November 2015 01:12:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Trip Due to Generator Lockout After Voltage Regulator Malfunction ENS 515062015-10-29T08:48:00029 October 2015 08:48:00 10 CFR 50.72(b)(3)(iv)(A), System Actuation Actuation of the Auxiliary Feedwater System Due to Main Transformer Lockout ENS 506492014-12-03T02:50:0003 December 2014 02:50:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Manual Reactor Trip Due to Failure of Condensate Pump ENS 494332013-10-13T14:46:00013 October 2013 14:46:00 10 CFR 50.72(a)(1)(i), Emergency Class Declaration ENS 487222013-02-06T17:43:0006 February 2013 17:43:00 10 CFR 50.72(a)(1)(i), Emergency Class Declaration, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Unusual Event - Loss of Offsite Power to Essential Buses for Greater than 15 Minutes ENS 481892012-08-15T01:31:00015 August 2012 01:31:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Unit 1 Manually Tripped in Anticipation of an Automatic Turbine Trip ENS 480532012-06-28T01:46:00028 June 2012 01:46:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Manual Reactor Trip Due to 100% Load Reject ENS 478632012-04-26T02:06:00026 April 2012 02:06:00 10 CFR 50.72(a)(1)(i), Emergency Class Declaration Alert Declared Due to Toxic Gas Build Up Following an Emergency Diesel Generator Test Run ENS 474782011-11-27T08:38:00027 November 2011 08:38:00 10 CFR 50.72(a)(1)(i), Emergency Class Declaration, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Unusual Event Due to a Loss of Offsite Power During Switching Operations ENS 464822010-12-15T07:48:00015 December 2010 07:48:00 10 CFR 50.72(b)(3)(iv)(A), System Actuation Unit 2 Manual Reactor Trip During Startup ENS 461292010-07-27T01:01:00027 July 2010 01:01:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Manual Reactor Trip Due to Loss of Condenser Vacuum ENS 460802010-07-09T11:47:0009 July 2010 11:47:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Manual Reactor Trip Due to a Feedwater Regulating Valve Failure ENS 460322010-06-19T11:36:00019 June 2010 11:36:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Manual Reactor Trip Due to Generator Lockout ENS 443362008-07-04T00:45:0004 July 2008 00:45:00 10 CFR 50.72(a)(1)(i), Emergency Class Declaration Sodium Hypochlorite Leak ENS 439072008-01-15T20:15:00015 January 2008 20:15:00 10 CFR 50.72(b)(2)(xi), Notification to Government Agency or News Release, 10 CFR 50.72(a)(1)(i), Emergency Class Declaration, 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Unusual Event - Loss of Offsite Power ENS 434072007-06-05T20:17:0005 June 2007 20:17:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Manual Reactor Trip After Feedwater Valve Failure ENS 429122006-10-17T02:26:00017 October 2006 02:26:00 10 CFR 50.72(a)(1)(i), Emergency Class Declaration Unusual Event - Identified Leakage Greater than 25 Gpm ENS 407542004-05-15T16:54:00015 May 2004 16:54:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Manual Reactor Trip Due to Diver Entangled in Intake Crib 2021-07-31T21:46:00 | |