ENS 45104: Difference between revisions

v t e ENS Event
02:40 May 29, 2009
Title	Loss of Control Power to Eccs Valves
Event Description	At 2140 on 5/28/09 Braidwood Station identified a loss of control power for a Safety Related MCC (Motor Control Center) which provided power to SVAG (Single Valve Actuation Group) valves associated with both trains of the ECCS system. The MCC is normally de-energized to maintain the valve power removed in accordance with Tech Specs for ECCS. Loss of the control power for the associated MCC would prevent operation of these valves, which would prevent realignment of components required for transfer to cold leg recirculation and hot leg recirculation for long term core cooling. Entry was made into LCO 3.5.2, ECCS Operating, and LCO 3.0.3 due to inoperability of both trains of ECCS based on the inability to realign portions of both trains of the ECCS system from injection to cold leg recirculation and subsequent hot leg recirculation. At 2230 on 5/28/09 preparations had been completed for ramp off line per LCO 3.0.3. Troubleshooting was performed and a blown control power fuse was identified and replaced at 2319 on 5/28/09. No Unit ramp was initiated. The NRC Resident Inspector was notified. * * RETRACTION ON 6/8/09 AT 12:27 EDT FROM KELLER TO HUFFMAN * * * The purpose of this report is to retract the ENS report made on May 29, 2009 at 04:49 EDT (ENS #45104) under 10CFR50.72(b)(3)(v)(B), a condition that could have prevented fulfillment of a safety function. The initial report was made based on identification of a loss of control power for a Safety Related MCC (Motor Control Center), which provided power to SVAG (Single Valve Actuation Group) valves associated with both trains of the ECCS system. The MCC is normally de-energized to maintain the valve power removed in accordance with Technical Specifications. The loss of the control power for the associated MCC would prevent operation of these valves. It was initially concluded that this condition would prevent realignment of components required for transfer to cold leg recirculation and hot leg recirculation for long term core cooling. Therefore, the referenced ENS report was made for a loss of safety function. Subsequent review of UFSAR information and previously developed analytical data determined that the safety function for ECCS was not lost due to the event. The failure of the MCC to energize would have NOT affected the ability of the 1B ECCS train to perform its design function of cold and hot leg recirculation. A blown control power fuse, the cause of the event, was identified and replaced on May 28, 2009 at 23:19 hours. The NRC Senior Resident Inspector has been notified of this retraction. R3DO(Pelke) notified.

ENS 45104 +/- *RETRACTED*
Where
Braidwood Illinois (NRC Region 3)
Reporting

10 CFR 50.72(b)(3)(v)(B), Loss of Safety Function - Remove Residual Heat
Time - Person (Reporting Time:+2.15 h0.0896 days <br />0.0128 weeks <br />0.00295 months <br />)
Opened:	James Smit 04:49 May 29, 2009
NRC Officer:	Mark Abramovitz
Last Updated:	Jun 8, 2009
45104 - 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 45104\u003C/a\u003E - \u003Ca href=\"/Braidwood\" title=\"Braidwood\"\u003EBraidwood\u003C/a\u003E\n\u003C/p\u003E\u003C/div\u003E\u003C/b\u003E\u003Cdiv class=\"mw-parser-output\"\u003E\u003Cp\u003ELoss of Control Power to Eccs Valves\n\u003C/p\u003E\u003C/div\u003E","title":"ENS 45104 - Braidwood\n","link":"","lat":41.24283055555556,"lon":-88.2290111111111,"icon":"/w/images/b/be/Constellation_icon.png"}],"imageoverlays":null}
v • d • e

v t e Emergency Notification System
Braidwood with 10 CFR 50.72(b)(3)(v)(B), Loss of Safety Function - Remove Residual Heat
WEEKMONTHYEAR2018-04-20T15:42:00 [Table view]
[ENS list for Braidwood]

@@ Line 17: / Line 17: @@
 | event date = 05/28/2009 21:40 CDT
 | last update date = 06/08/2009
-| title = Loss Of Control Power To Eccs Valves
+| title = Loss of Control Power to Eccs Valves
 | event text = At 2140 on 5/28/09 Braidwood Station identified a loss of control power for a Safety Related MCC (Motor Control Center) which provided power to SVAG (Single Valve Actuation Group) valves associated with both trains of the ECCS system.  The MCC is normally de-energized to maintain the valve power removed in accordance with Tech Specs for ECCS.  Loss of the control power for the associated MCC would prevent operation of these valves, which would prevent realignment of components required for transfer to cold leg recirculation and hot leg recirculation for long term core cooling.
 Entry was made into LCO 3.5.2, ECCS Operating, and LCO 3.0.3 due to inoperability of both trains of ECCS based on the inability to realign portions of both trains of the ECCS system from injection to cold leg recirculation and subsequent hot leg recirculation.  At 2230 on 5/28/09 preparations had been completed for ramp off line per LCO 3.0.3.

v t e Unit 1
W-4-LP
Reactor critical	Critical
Scram	No
Before	Power Operation (100 %)
After	Power Operation (100 %)

ENS 45104: Difference between revisions

Latest revision as of 22:11, 1 March 2018

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ENS 45104: Difference between revisions

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