ENS 55239
From kanterella
(diff) ← Older revision | Latest revision (diff) | Newer revision → (diff)
ENS Event | |
|---|---|
16:23 May 6, 2021 | |
| Title | Manual Reactor Trip |
| Event Description | On May 6, 2021 at 1223 [EDT], Unit 1 was manually tripped from 60 percent power due to degrading main condenser vacuum. Unit 1 was in the process of decreasing power due to increased secondary sodium levels identified earlier in the day. The Operations crew entered the reactor trip procedure and stabilized Unit 1 in Mode 3 at normal operating temperature and pressure. All control rods fully inserted into the core following the reactor trip. This reactor protection actuation is reportable per 10 CFR 50.72(b)(2)(iv)(B). Auxiliary Feedwater pumps actuated as designed as a result of the reactor trip and provided makeup flow to the steam generators. The automatic start of the Auxiliary Feedwater pumps is reportable per 10 CFR 50,72(b)(3)(iv)(A) for a valid actuation of an ESF [Engineered Safeguards Features] system. Decay heat is being removed by the condenser steam dump system.
The electrical system is in normal lineup for shutdown conditions. There was no effect on Unit 2 operation. The NRC resident inspector has been notified. |
| Where | |
|---|---|
North Anna  Virginia (NRC Region 2) | |
| Reporting | |
| 10 CFR 50.72(b)(2)(iv)(B), RPS Actuation | |
| Time - Person (Reporting Time:+-2.38 h-0.0992 days <br />-0.0142 weeks <br />-0.00326 months <br />) | |
| Opened: | Marc Hofmann 14:00 May 6, 2021 |
| NRC Officer: | Thomas Kendzia |
| Last Updated: | May 6, 2021 |
| 55239 - NRC Website | |
Unit 1 | |
|---|---|
| Reactor critical | Critical |
| Scram | Yes, Manual Scram |
| Before | Power Operation (60 %) |
| After | Hot Standby (0 %) |
WEEKMONTHYEARENS 558432022-04-14T13:28:00014 April 2022 13:28:00
[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 Trip During Control Rod Testing ENS 552392021-05-06T16:23:0006 May 2021 16:23:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Manual Reactor Trip ENS 539082019-03-03T03:37:0003 March 2019 03:37:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Manual Reactor Trip Due to Degrading Main Condenser Vacuum ENS 509462015-04-02T08:26:0002 April 2015 08:26:00 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 Main Generator Voltage Regulator Failure ENS 508512015-02-26T20:11:00026 February 2015 20:11:00 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 Feedwater Regulating Valve Failing Closed ENS 497842014-02-02T13:59:0002 February 2014 13:59:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Manual Reactor Trip Following Loss of the "a" Main Feedwater Pump ENS 494292013-10-11T17:17:00011 October 2013 17:17:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Turbine and Reactor Trip Due to Station Service Transformer Lockout ENS 490752013-05-28T19:07:00028 May 2013 19:07:00 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 Transient ENS 490202013-05-10T10:12:00010 May 2013 10:12:00 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 High Turbine Bearing Vibration ENS 484362012-10-24T05:47:00024 October 2012 05:47:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Trip on Low Steam Generator Water Level ENS 463522010-10-22T10:36:00022 October 2010 10:36:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation Manual Reactor Trip During Physics Testing Due to Problems with the Rod Control in Hold Out Switch ENS 460202010-06-16T23:20:00016 June 2010 23:20:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Trip Due to a Lightning Storm ENS 459602010-05-28T04:03:00028 May 2010 04:03:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Trip Due to Loss of Reactor Coolant Pump ENS 458772010-04-27T20:37:00027 April 2010 20:37:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Reactor Trip Following a Generator Lockout During Automatic Voltage Regulator Testing ENS 455562009-12-09T19:23:0009 December 2009 19:23:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Trip on Unit 2 and Edg Start on Both Units Due to Inadvertent Loss of "C" Reserve Station Service Transformer ENS 438662007-12-26T02:10:00026 December 2007 02:10:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Trip Due to Trip of "B" Reactor Coolant Pump ENS 434622007-06-29T21:52:00029 June 2007 21:52:00 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 Trip and Spurious Safety Injection ENS 430722007-01-03T23:03:0003 January 2007 23:03:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Trip Due to a Card Failure ENS 429962006-11-16T07:26:00016 November 2006 07:26:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Reactor Trip ENS 418982005-08-06T02:28:0006 August 2005 02:28:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Trip Apparently Due to Lightning Strike ENS 408042004-06-10T17:13:00010 June 2004 17:13:00 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation Automatic Reactor Trip While Performing Scheduled Solid State Protection Testing 2022-04-14T13:28:00 | |
Retrieved from "https://kanterella.com/w/index.php?title=ENS_55239&oldid=3251306"