ENS 45944: Difference between revisions

v t e ENS Event
23:37 May 21, 2010
Title	Automatic Reactor Trip on Turbine Trip
Event Description	At 1937 Eastern Daylight Saving Time (EDT), Watts Bar Nuclear Power Plant Unit 1 experienced a reactor trip due to a turbine trip. This caused an automatic AFW Pump start from P-4 coincident with Lo Tave signal. The cause of the turbine trip has not yet been identified, and is under investigation. The plant is stable and is being maintained in Mode 3, at normal operating pressure and temperature, with steam generator and pressurizer levels normal. Plant systems responded to return the plant to a stable condition without complication, and all systems performed as expected with one exception: The 'B' Motor Driven Auxiliary Feedwater Backpressure Control Valve failed closed, but the Steam Driven Auxiliary Feedwater Pump provided sufficient feedwater so that all Steam Generators were provided sufficient feedwater to maintain cooling and normal steam generator level. Plans for plant restart are pending awaiting the cause investigation. All control rods inserted into the core. Plant decay heat removal is through the steam dumps to the main condenser. Offsite power is available and lined up to plant system loads. Watts Bar [NRC] Resident Inspector has been notified of this event.

ENS 45944 +/-
Where
Watts Bar Tennessee (NRC Region 2)
Reporting

10 CFR 50.72(b)(2)(iv)(B), RPS Actuation 10 CFR 50.72(b)(3)(iv)(A), System Actuation
Time - Person (Reporting Time:+-0.67 h-0.0279 days <br />-0.00399 weeks <br />-9.17766e-4 months <br />)
Opened:	Wes Daniel 22:57 May 21, 2010
NRC Officer:	Joe O'Hara
Last Updated:	May 21, 2010
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v • d • e

v t e Emergency Notification System
Watts Bar with 10 CFR 50.72(b)(2)(iv)(B), RPS System Actuation, 10 CFR 50.72(b)(3)(iv)(A), System Actuation
WEEKMONTHYEAR2024-07-08T19:21:00 [Table view]
[ENS list for Watts Bar]

@@ Line 16: / Line 16: @@
 | event date = 05/21/2010 19:37 EDT
 | last update date = 05/21/2010
-| title = Automatic Reactor Trip On Turbine Trip
+| title = Automatic Reactor Trip on Turbine Trip
 | event text = At 1937 Eastern Daylight Saving Time (EDT), Watts Bar Nuclear Power Plant Unit 1 experienced a reactor trip due to a turbine trip.  This caused an automatic AFW Pump start from P-4 coincident with Lo Tave signal.  The cause of the turbine trip has not yet been identified, and is under investigation.
 The plant is stable and is being maintained in Mode 3, at normal operating pressure and temperature, with steam generator and pressurizer levels normal.

Latest revision as of 21:09, 1 March 2018