ENS 46359: Difference between revisions

v t e ENS Event
20:41 Oct 24, 2010
Title	Automatic Reactor Scram Due to a Turbine Trip Resulting from a Low Condenser Vacuum
Event Description	At 1641 EDT 10/24/10, the reactor mode switch was taken to shutdown following an automatic scram due to a main turbine trip, caused by a loss of [condenser] vacuum. The scram was uncomplicated, Control Rod 10-35 did not fully insert on scram and was manually inserted from position 38. The lowest reactor vessel water level reached was 137 inches, and as expected, HPCI, RCIC. & SRVs did not actuate. Reactor water level is being controlled in the normal band using the CRD [Control Rod Drive] and reactor feedwater systems. All isolations and actuations for reactor water level 3 occurred as expected. The loss of condenser vacuum is under investigation. All Emergency Core Cooling Systems and EDG's [Emergency Diesel Generators] were operable, and no safety related equipment was out of service. This report is being made in accordance with 10 CFR 50.72(b)(2)(iv)(B), as an event that results in actuation of the reactor protection system (RPS) when the reactor is critical. Decay heat is being removed through the main turbine bypass valves to the main condenser. Electrical offsite power lineups are normal. Reactor pressure is 882 psig and reactor temperature is 515 degrees F (NOP and NOT). The reactor is stable in mode 3. The licensee notified the NRC Resident Inspector.

ENS 46359 +/-
Where
Fermi Michigan (NRC Region 3)
Reporting

10 CFR 50.72(b)(2)(iv)(B), RPS Actuation
LER:	05000341/LER-2010-003
Time - Person (Reporting Time:+-2.53 h-0.105 days <br />-0.0151 weeks <br />-0.00347 months <br />)
Opened:	Mark Eghigian 18:09 Oct 24, 2010
NRC Officer:	Vince Klco
Last Updated:	Oct 24, 2010
46359 - 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 46359\u003C/a\u003E - \u003Ca href=\"/Fermi\" title=\"Fermi\"\u003EFermi\u003C/a\u003E\n\u003C/p\u003E\u003C/div\u003E\u003C/b\u003E\u003Cdiv class=\"mw-parser-output\"\u003E\u003Cp\u003EAutomatic Reactor Scram Due to a Turbine Trip Resulting from a Low Condenser Vacuum\n\u003C/p\u003E\u003C/div\u003E","title":"ENS 46359 - Fermi\n","link":"","lat":41.96295277777778,"lon":-83.25779444444444,"icon":"/w/images/5/5b/DTE_Energy_icon.png"}],"imageoverlays":null}
v • d • e

v t e Emergency Notification System
Fermi with 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation
WEEKMONTHYEAR2024-03-23T04:04:00 [Table view]
[ENS list for Fermi]

@@ Line 16: / Line 16: @@
 | event date = 10/24/2010 16:41 EDT
 | last update date = 10/24/2010
-| title = Automatic Reactor Scram Due To A Turbine Trip Resulting From A Low Condenser Vacuum
+| title = Automatic Reactor Scram Due to a Turbine Trip Resulting from a Low Condenser Vacuum
 | event text = At 1641 EDT 10/24/10, the reactor mode switch was taken to shutdown following an automatic scram due to a main turbine trip, caused by a loss of [condenser] vacuum. The scram was uncomplicated, Control Rod 10-35 did not fully insert on scram and was manually inserted from position 38. The lowest reactor vessel water level reached was 137 inches, and as expected, HPCI, RCIC. & SRVs did not actuate. Reactor water level is being controlled in the normal band using the CRD [Control Rod Drive] and reactor feedwater systems. All isolations and actuations for reactor water level 3 occurred as expected.
 The loss of condenser vacuum is under investigation.

Latest revision as of 21:08, 1 March 2018