ENS 45154
ENS Event | |
---|---|
22:04 Jun 23, 2009 | |
Title | Auto Start of Emergency Diesel Generators Due to Offsite Voltage Transient |
Event Description | This report is being made under 10CFR50.72(b)(3)(iv)(A), 'Any event or condition that results in valid actuation of any of the systems listed in paragraph (b)(3)(iv)(A) of this section' due to the auto start of the 'A' and 'B' Standby Diesel Generators.
The auto start of the 'A' and 'B' Standby Diesel Generators occurred on a valid bus undervoltage condition caused by a transient on the 161 kV Fairfax line while there were severe thunderstorms in the DAEC area. The Standby Diesel Generator supply breakers did not close onto their respective essential buses. The essential buses were not required to load onto either diesel as they remained powered from their normal power supply, 1X003 Start-up Transformer, during and after the event. Offsite power remained fully operable during and following the event. The Standby Diesel Generators have been returned to the standby/readiness condition. As designed, both Emergency Service Water systems auto started when the SBDGs started. The Emergency Service Water systems have been returned to the standby/readiness condition. All ECCS systems were available before the event and have remained available following the event. The NRC Resident Inspector has been informed of the automatic SBDG start. |
Where | |
---|---|
Duane Arnold Iowa (NRC Region 3) | |
Reporting | |
10 CFR 50.72(b)(3)(iv)(A), System Actuation | |
Time - Person (Reporting Time:+1.55 h0.0646 days <br />0.00923 weeks <br />0.00212 months <br />) | |
Opened: | Ellis Vann 23:37 Jun 23, 2009 |
NRC Officer: | Bill Huffman |
Last Updated: | Jun 24, 2009 |
45154 - NRC Website | |
Unit 1 | |
---|---|
Reactor critical | Critical |
Scram | No |
Before | Power Operation (100 %) |
After | Power Operation (100 %) |
WEEKMONTHYEARENS 540122019-04-20T10:07:00020 April 2019 10:07:00
[Table view]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 Both Reactor Feed Pumps Trip Causing Manual Reactor Scram and Eccs Injection ENS 536762018-10-19T05:00:00019 October 2018 05:00:00 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 Automatic Reactor Trip Due to Feedwater Regulating Valve Failing Closed ENS 514842015-10-20T23:00:00020 October 2015 23:00:00 10 CFR 50.72(b)(3)(iv)(A), System Actuation Diesel Generators Started After Transmission Line Lightning Strikes ENS 502462014-07-01T00:13:0001 July 2014 00:13:00 10 CFR 50.72(b)(3)(iv)(A), System Actuation Auto-Start of Standby Diesel Generators Due to a Grid Disturbance ENS 471432011-08-11T16:38:00011 August 2011 16:38:00 10 CFR 50.72(b)(3)(iv)(A), System Actuation Unplanned Primary Containment Isolations ENS 456032010-01-02T05:10:0002 January 2010 05:10:00 10 CFR 50.72(b)(3)(iv)(A), System Actuation Diesel Generator Auto Start Due to Failed Line Arrestor in Switchyard ENS 454212009-10-08T19:20:0008 October 2009 19:20:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Scram During Testing ENS 451542009-06-23T22:04:00023 June 2009 22:04:00 10 CFR 50.72(b)(3)(iv)(A), System Actuation Auto Start of Emergency Diesel Generators Due to Offsite Voltage Transient ENS 449652009-04-03T05:28:0003 April 2009 05:28:00 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 Increasing Reactor Water Level During Calibration ENS 448212009-02-02T00:00:0002 February 2009 00:00:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Manual Reactor Scram Due to Loss of Condenser Cooling ENS 438172007-12-01T20:35:0001 December 2007 20:35:00 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Edg Starts on 161 Kv Line Transient ENS 432712007-04-02T16:25:0002 April 2007 16:25:00 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 Lowering Reactor Vessel Water Level ENS 432472007-03-19T00:40:00019 March 2007 00:40:00 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 Coolant Chemistry Concerns ENS 432102007-03-03T05:32:0003 March 2007 05:32:00 10 CFR 50.72(b)(3)(iv)(A), System Actuation Reactor Scram Signal Due to High Discharge Volume Level ENS 431852007-02-24T23:56:00024 February 2007 23:56:00 10 CFR 50.72(b)(3)(v)(A), Loss of Safety Function - Shutdown the Reactor, 10 CFR 50.72(b)(3)(v)(B), Loss of Safety Function - Remove Residual Heat, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Loss of Normal Electrical Lineup Due to Grid Instability from Adverse Weather Conditions ENS 429662006-11-06T07:10:0006 November 2006 07:10:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Scram During Turbine Testing ENS 403532003-11-25T21:22:00025 November 2003 21:22:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Manual Scram Due to Degrading Condenser Vacuum During Power Ascension ENS 403012003-11-07T07:34:0007 November 2003 07:34:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Manual Scram at Duane Arnold Due to Hi Coolant Conductivity 2019-04-20T10:07:00 | |