ENS Event | |
|---|---|
06:23 Jan 30, 2016 | |
| Title | Unanticipated Sfrcs Actuation While Restoring Main Feedwater to Steam Generators |
| Event Description | At 0123 EST, with the unit shutdown in Mode 3 (Hot Standby), during the performance of procedure DB-OP-06910, 'Trip Recovery,' while attempting to restore main feedwater to the Steam Generators, Davis-Besse received a Steam Feedwater Rupture Control System (SFRCS) 'reverse delta pressure' signal to the Auxiliary Feedwater System (AFW). The Auxiliary Feedwater System was operating at the time, feeding the Steam Generators.
The SFRCS signal did result in actuation/closure [of] several valves in the Main Steam System, as the SFRCS signal is designed to do. This SFRCS signal/valve actuation was not anticipated. The unit remained in Mode 3 and is stable. This actuation did not have any negative impact to the AFW system and the ability to feed the steam generators. The NRC Resident Inspector has been notified of the event. |
| Where | |
|---|---|
Davis Besse  Ohio (NRC Region 3) | |
| Reporting | |
| 10 CFR 50.72(b)(3)(iv)(A), System Actuation | |
| LER: | 05000346/LER-2016-002 Regarding Unanticipated Steam and Feedwater Rupture Control System Actuation |
| Time - Person (Reporting Time:+1.15 h0.0479 days <br />0.00685 weeks <br />0.00158 months <br />) | |
| Opened: | Mark Helle 07:32 Jan 30, 2016 |
| NRC Officer: | Steve Sandin |
| Last Updated: | Jan 30, 2016 |
| 51702 - NRC Website
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Unit 1 | |
|---|---|
| Reactor critical | Not Critical |
| Scram | No |
| Before | Hot Standby (0 %) |
| After | Hot Standby (0 %) |
WEEKMONTHYEARENS 522322016-09-10T07:43:00010 September 2016 07:43:00
[Table view]10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Unit Trip Due to Main Generator Lock-Out ENS 517022016-01-30T06:23:00030 January 2016 06:23:00 10 CFR 50.72(b)(3)(iv)(A), System Actuation Unanticipated Sfrcs Actuation While Restoring Main Feedwater to Steam Generators ENS 516962016-01-29T18:22:00029 January 2016 18:22:00 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 Reactor Protection System Actuation ENS 510612015-05-09T22:55:0009 May 2015 22:55:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(a)(1)(i), Emergency Class Declaration, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Unusual Event Declared Due to Steam Leak in the Turbine Building ENS 500862014-05-05T18:56:0005 May 2014 18:56:00 10 CFR 50.72(b)(3)(iv)(A), System Actuation Manual Reactor Scram with Rod Motion While Shutdown ENS 500972014-05-04T12:32:0004 May 2014 12:32:00 10 CFR 50.72(b)(3)(iv)(A), System Actuation Manual Initiation of the Reactor Protection System While Shutdown ENS 413302005-01-13T14:49:00013 January 2005 14:49:00 10 CFR 50.72(b)(3)(iv)(A), System Actuation, 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Entry Into Technical Specification Required Shut Down Due to Loss of Essential Bus ENS 402082003-10-01T01:34:0001 October 2003 01:34:00 10 CFR 50.72(b)(3)(iv)(A), System Actuation Valid Specified System Actuation ENS 401612003-09-16T04:30:00016 September 2003 04:30:00 10 CFR 50.72(b)(3)(iv)(A), System Actuation Reactor Coolant System Pressure Increase Caused a Valid Signal 2016-09-10T07:43:00 | |