ENS 41585
ENS Event | |
|---|---|
15:50 Apr 10, 2005 | |
| Title | Technical Specification Required Shutdown Due to Failed 125V Dc Battery Charger |
| Event Description | At 0352 the 2C 125VDC battery charger failed. Fuses internal to the charger were found blown. Technical Specifications require restoration of the charger within 2 hrs or enter Mode 3 within the next 12 hrs and Mode 4 within the next 36 hrs. Investigation has not been able to restore the charger, and therefore the shutdown of the unit has commenced. Loads are currently being carried by the batteries, and personnel are monitoring battery voltage. Initial investigation has not identified any generic issues or any indication of tampering.
This event is a Technical Specification required shutdown, and is reportable as a four hour ENS Notification under 10 CFR 50.72(b)(2)(i). Additionally, this is a voluntary notification due to an anticipated press release associated with the downpower towards unit shutdown. There is evidence of degraded insulation on wires inside the affected battery charger. Battery loads are very small with an initial estimate of battery life at 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br />. All safety systems are operable. There is no impact on Unit 1. Unit 2 is expected to reach Mode 3 at 1720 on 4/10/05. The NRC Resident Inspector has been notified. State (FEMA) will be notified.
At 17:28 the plant completed a normal reactor shutdown and entered Mode 3 in accordance with plant procedures to fulfill the requirements of Technical Specification 3.8.4. There were no ECCS initiations and lowest water level was approximately -4 inches. The licensee reported that the 2C battery charger was back in service but remained in the LCO due to battery requirements. They are also completing engineering evaluations for extent of condition. The NRC Resident Inspector was notified. R1DO (Noggle) notified.
At 16:28 on April 12th, 2005 Susquehanna Unit 2 entered Mode 2 (Start-up) following the completion of repairs to the failed 125VDC battery charger and inspection to the remaining 3 Unit 2 125VDC battery chargers. A courtesy call was made [to] the Pennsylvania Emergency Management Agency. An informational press release will be made. The NRC Resident Inspector was notified by the licensee. R1DO (White) was notified. |
| Where | |
|---|---|
Susquehanna  Pennsylvania (NRC Region 1) | |
| Reporting | |
| 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown | |
| Time - Person (Reporting Time:+-3.7 h-0.154 days <br />-0.022 weeks <br />-0.00507 months <br />) | |
| Opened: | Gordon Robinson 12:08 Apr 10, 2005 |
| NRC Officer: | Wesley Held |
| Last Updated: | Apr 12, 2005 |
| 41585 - NRC Website | |
Unit 2 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (100 %) |
| After | Power Operation (99 %) |
WEEKMONTHYEARENS 540782019-05-22T06:56:00022 May 2019 06:56:00
[Table view]10 CFR 50.72(b)(3)(v)(A), Loss of Safety Function - Shutdown the Reactor, 10 CFR 50.72(b)(3)(v)(B), Loss of Safety Function - Remove Residual Heat, 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown, 10 CFR 50.72(b)(3)(v)(C), Loss of Safety Function - Release of Radioactive Material Technical Specification Required Shutdown ENS 519832016-06-06T09:56:0006 June 2016 09:56:00 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown, 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Isolable Leakage Identified from Seal Water Line Weld Inside Rcs Pressure Boundary ENS 485952012-12-14T18:50:00014 December 2012 18:50:00 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident, 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Technical Specification Required Shutdown - Control Structure Chillers Inoperable ENS 480362012-06-19T21:20:00019 June 2012 21:20:00 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown, 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Mode Change Required by Technical Specifications ENS 466542011-03-04T03:59:0004 March 2011 03:59:00 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Techncial Specification Required Shutdown Due to Inoperable Hpci ENS 437222007-10-13T06:20:00013 October 2007 06:20:00 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Technical Specification Required Shutdown Due to Inoperable Control Rods ENS 423852006-03-04T10:17:0004 March 2006 10:17:00 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Control Rods Declared Inoperable During Shutdown ENS 420932005-10-29T03:32:00029 October 2005 03:32:00 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Technical Specification Required Shutdown Due to Inoperable Control Rods ENS 415852005-04-10T15:50:00010 April 2005 15:50:00 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Technical Specification Required Shutdown Due to Failed 125V Dc Battery Charger 2019-05-22T06:56:00 | |