ENS 41193
ENS Event | |
|---|---|
06:00 Sep 28, 2004 | |
| Title | Invalid Specified System Actuation Due to Bus Voltage Dip During Recirc Mg Start |
| Event Description | {{#Wiki_filter:This 60-day optional report, as allowed by 10 CFR 50.73(a)(1), is being made under the reporting requirement in 10CFR50.73(a)(2)(iv)(A) to describe an unplanned, invalid actuation of specified systems, specifically the Unit 2 Primary Containment Isolation System (PCIS).
On 9/28/04, at approximately 0100 hours [EDT], a Group III Outboard PCIS isolation occurred during the start of the 2B Recirculation Motor / Generator (M/G) Set. The Recirculation M/G Set was being started to perform post-maintenance testing during the refueling outage subsequent to work involving the Recirculation M/G Set. This outboard isolation resulted in the closure of various valves associated with the Reactor Building / Refueling Floor Ventilation Systems and the start of the 'B' Standby Gas Treatment Fan. All equipment operated as designed. The isolation occurred as a result of a voltage dip on the 2B Reactor Protection System (RPS) / PCIS power supply while on its alternate feed at the time that the 2B Recirculation M/G Set was started. The 2B RPS / PCIS power supply was on the alternate feed in preparation for planned testing of the Emergency Diesel Generators (LOCA-LOOP testing). This RPS / PCIS power supply alternate feed was fed from the same startup transformer that the 2B Recirculation MG Set is fed from. The voltage dip from the start of the large Recirculation M/G Set was sufficient to cause the protective relaying on the 2B RPS /PCIS alternate feed power supply to shed the power supply from the 2B RPS / PCIS bus. Deenergization of the bus caused the Group III Outboard PCIS isolation. A � RPS scram signal was also generated. Just prior to the start of the 2B Recirculation M/G set, Operations personnel were briefed on the probability of the isolation and were prepared to take prompt action to reset the isolation and � Scram. The 2B RPS / PCIS power supply was returned to its normal power supply (i.e. 2B RPS M/G Set) and the Group III PCIS and the � Scram was promptly reset by 0105 hours. This issue has been entered into the Corrective Action Program (CR 257503). The NRC Resident Inspector has been informed of this notification. }}[[Event description::Description::{{#Regex_clear:This 60-day optional report, as allowed by 10 CFR 50.73(a)(1), is being made under the reporting requirement in 10CFR50.73(a)(2)(iv)(A) to describe an unplanned, invalid actuation of specified systems, specifically the Unit 2 Primary Containment Isolation System (PCIS). On 9/28/04, at approximately 0100 hours [EDT], a Group III Outboard PCIS isolation occurred during the start of the 2B Recirculation Motor / Generator (M/G) Set. The Recirculation M/G Set was being started to perform post-maintenance testing during the refueling outage subsequent to work involving the Recirculation M/G Set. This outboard isolation resulted in the closure of various valves associated with the Reactor Building / Refueling Floor Ventilation Systems and the start of the 'B' Standby Gas Treatment Fan. All equipment operated as designed. The isolation occurred as a result of a voltage dip on the 2B Reactor Protection System (RPS) / PCIS power supply while on its alternate feed at the time that the 2B Recirculation M/G Set was started. The 2B RPS / PCIS power supply was on the alternate feed in preparation for planned testing of the Emergency Diesel Generators (LOCA-LOOP testing). This RPS / PCIS power supply alternate feed was fed from the same startup transformer that the 2B Recirculation MG Set is fed from. The voltage dip from the start of the large Recirculation M/G Set was sufficient to cause the protective relaying on the 2B RPS /PCIS alternate feed power supply to shed the power supply from the 2B RPS / PCIS bus. Deenergization of the bus caused the Group III Outboard PCIS isolation. A � RPS scram signal was also generated. Just prior to the start of the 2B Recirculation M/G set, Operations personnel were briefed on the probability of the isolation and were prepared to take prompt action to reset the isolation and � Scram. The 2B RPS / PCIS power supply was returned to its normal power supply (i.e. 2B RPS M/G Set) and the Group III PCIS and the � Scram was promptly reset by 0105 hours. This issue has been entered into the Corrective Action Program (CR 257503). The NRC Resident Inspector has been informed of this notification. }}| ]] |
| Where | |
|---|---|
Peach Bottom  Pennsylvania (NRC Region 1) | |
| Reporting | |
| 10 CFR 50.73(a)(1), Submit an LER, Invalid Actuation | |
| Time - Person (Reporting Time:+1083.97 h45.165 days <br />6.452 weeks <br />1.485 months <br />) | |
| Opened: | David Foss 10:58 Nov 12, 2004 |
| NRC Officer: | Jeff Rotton |
| Last Updated: | Nov 12, 2004 |
| 41193 - NRC Website | |
WEEKMONTHYEARENS 562802022-11-12T04:33:00012 November 2022 04:33:00
[Table view]10 CFR 50.73(a)(1), Submit an LER 60-DAY Telephonic Notification ENS 548202020-06-08T08:24:0008 June 2020 08:24:00 10 CFR 50.73(a)(1), Submit an LER Invalid Specified System Actuation ENS 529612017-07-14T18:53:00014 July 2017 18:53:00 10 CFR 50.73(a)(1), Submit an LER Invalid Actuation of Containment Isolation Valves ENS 519622016-03-28T17:20:00028 March 2016 17:20:00 10 CFR 50.73(a)(1), Submit an LER Invalid Specified System Actuation ENS 500892014-03-09T21:13:0009 March 2014 21:13:00 10 CFR 50.73(a)(1), Submit an LER 60-Day Optional Telephonic Notification for an Invalid Actuation of an Emergency Service Water System ENS 479072012-03-13T20:04:00013 March 2012 20:04:00 10 CFR 50.73(a)(1), Submit an LER 60-Day Optional Report - Invalid Primary Containment Isolation System Actuation ENS 449402009-03-02T15:55:0002 March 2009 15:55:00 10 CFR 50.73(a)(1), Submit an LER Invalid Primary Containment Isolation Signal Due to Maintenance Error ENS 444652008-07-24T03:25:00024 July 2008 03:25:00 10 CFR 50.73(a)(1), Submit an LER Invalid System Actuation Due to Loss of One Offsite Power Circuit to Safety Buses ENS 439102007-12-11T21:45:00011 December 2007 21:45:00 10 CFR 50.73(a)(1), Submit an LER 60-Day Notification of an Invalid Actuation of Units 2 and 3 Primary Containment Isolation Systems ENS 411932004-09-28T06:00:00028 September 2004 06:00:00 10 CFR 50.73(a)(1), Submit an LER Invalid Specified System Actuation Due to Bus Voltage Dip During Recirc Mg Start ENS 411922004-09-18T08:57:00018 September 2004 08:57:00 10 CFR 50.73(a)(1), Submit an LER Invalid Specified System Actuation Due to Off Site Power Source Fast Transfer ENS 408192004-04-25T05:05:00025 April 2004 05:05:00 10 CFR 50.73(a)(1), Submit an LER Invalid System Actuation ENS 401982003-09-25T04:00:00025 September 2003 04:00:00 10 CFR 50.72(b)(3)(iv)(A), System Actuation, 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown, 10 CFR 50.73(a)(1), Submit an LER Initiation of a Technical Specification Required Shutdown at Peach Bottom 2 ENS 401042003-07-27T22:39:00027 July 2003 22:39:00 10 CFR 50.73(a)(1), Submit an LER 60 Day Optional Report 2022-11-12T04:33:00 | |