ENS 46504
ENS Event | |
---|---|
10:09 Nov 14, 2010 | |
Title | Invalid Actuation of Turbine Driven Auxiliary Feedwater Pump |
Event Description | This report is a 60-day telephone notification in lieu of written LER being made under 10CFR50.73(a)(2)(iv)(A) and 10CFR50.73(a)(1). The event was an invalid actuation of the Unit 1 turbine driven auxiliary feedwater (TDAFW) pump.
At 0509 EST on 11/14/2010, during testing of the 1B main feedwater pump (MFP), the TDAFW pump started and the motor driven auxiliary feedwater (MDAFW) valves received a signal to go to automatic control. An investigation determined that during previous testing of the 1A MFP, the 1A MFP trip relay (RTT-1) remained stuck in the trip condition. The stuck relay on the 1A MFP and the trip test on 1B MFP made up the logic for a TDAFW and MDAFW start from both MFPs tripped signal. The 1A MFP trip relay was replaced. The Unit 1A and B train MDAFW and TDAFW system received the actuation signal. The 1A and 1B MDAFW pumps were already in service at the time for Mode 3 operation. Actual plant conditions did not exist that required an automatic start of the auxiliary feedwater system. Therefore, this actuation was invalid. A complete train actuation occurred and the auxiliary feedwater system functioned successfully. The licensee has notified the NRC Resident Inspector. |
Where | |
---|---|
Sequoyah Tennessee (NRC Region 2) | |
Reporting | |
10 CFR 50.73(a)(1), Submit an LER, Invalid Actuation | |
Time - Person (Reporting Time:+923.4 h38.475 days <br />5.496 weeks <br />1.265 months <br />) | |
Opened: | Dennis Dimopoulos 21:33 Dec 22, 2010 |
NRC Officer: | John Knoke |
Last Updated: | Dec 22, 2010 |
46504 - 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 46504\u003C/a\u003E - \u003Ca href=\"/Sequoyah\" title=\"Sequoyah\"\u003ESequoyah\u003C/a\u003E\n\u003C/p\u003E\u003C/div\u003E\u003C/b\u003E\u003Cdiv class=\"mw-parser-output\"\u003E\u003Cp\u003EInvalid Actuation of Turbine Driven Auxiliary Feedwater Pump\n\u003C/p\u003E\u003C/div\u003E","title":"ENS 46504 - Sequoyah\n","link":"","lat":35.22651944444444,"lon":-85.09192777777778,"icon":"/w/images/c/ce/Tennessee_Valley_Authority_icon.png"}],"imageoverlays":null} | |
Unit 1 | |
---|---|
Reactor critical | Not Critical |
Scram | No |
Before | Hot Standby (0 %) |
After | Hot Standby (0 %) |
WEEKMONTHYEARENS 551302021-01-11T16:52:00011 January 2021 16:52:00
[Table view]10 CFR 50.73(a)(1), Submit an LER 60-Day Optional Telephonic Notification for Invalid Containment Ventilation Isolation Actuation ENS 514512015-08-07T23:19:0007 August 2015 23:19:00 10 CFR 50.73(a)(1), Submit an LER 60-Day Optional Telephone Notification for an Invalid Containment Isolation Activation ENS 511172015-04-12T17:20:00012 April 2015 17:20:00 10 CFR 50.73(a)(1), Submit an LER 60-Day Optional Telephonic Notification for an Invalid Containment Isolation Activation. ENS 470222011-06-04T19:17:0004 June 2011 19:17:00 10 CFR 50.73(a)(1), Submit an LER Invalid Specified System Actuation Caused All 4 Emergency Diesel Generators to Start ENS 472492011-05-05T19:20:0005 May 2011 19:20:00 10 CFR 50.73(a)(1), Submit an LER Invalid Specified System Actuation ENS 465042010-11-14T10:09:00014 November 2010 10:09:00 10 CFR 50.73(a)(1), Submit an LER Invalid Actuation of Turbine Driven Auxiliary Feedwater Pump ENS 450852009-04-09T05:15:0009 April 2009 05:15:00 10 CFR 50.73(a)(1), Submit an LER Optional 60-Day Telephone Report of an Invalid Start of All Four Emergency Diesel Generators 2021-01-11T16:52:00 | |