ENS 41502
ENS Event | |
|---|---|
22:00 Mar 18, 2005 | |
| Title | Technical Specification Required Shutdown Due to Inoperable Diesel Generator |
| Event Description | The following information was obtained from the licensee via facsimile (licensee text in quotes):
The following event description is based on information currently available. If through subsequent reviews of this event, additional information is identified that is pertinent to this event or alters the information being provided at this time, a follow-up notification will be made via the ENS or under the reporting requirements of 10CFR50.73. On March 18, 2005, at approximately 15:00 hours Mountain Standard Time (MST), Palo Verde Nuclear Generating Station (PVNGS) Unit 1 commenced a reactor shutdown required by Technical Specification 3.8.1. Limiting Condition for Operability (LCO) 3.8.1 requires two diesel generators (DGs) each capable of supplying one train of the onsite Class 1E AC Electrical Power Distribution System be available. On March 17, 2005, at approximately 04:11 MST, Unit 1 Diesel Generator "A" failed to start during its post maintenance retest. The diesel generator (DG) tripped on incomplete sequence. Prior to tripping, the DG reached approximately 100 rpm for fifteen seconds. It has been determined that the cause of the DG failure was due to a governor failure. The failed governor has been replaced. At 17:50 on March 17, 2005, DG "B" was tested satisfactorily to confirm there is not a common cause failure. Unit 1 is being shutdown because the retest of DG "A" requires the Unit to be in Mode 5. The LCO 3.8.1 would expire at 04:00 MST, March 19, 2005 requiring initiation of Shut Down required by Technical Specifications if no action was taken. The event did not result in the release of radioactivity to the environment and did not adversely affect the safe operation of the plant or health and safety of the public. The NRC Resident Inspector has been notified. At the time of the notification, power was 70% and was being reduced in preparation for reactor shutdown to Mode 3. |
| Where | |
|---|---|
Palo Verde  Arizona (NRC Region 4) | |
| Reporting | |
| 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown | |
| Time - Person (Reporting Time:+-4.15 h-0.173 days <br />-0.0247 weeks <br />-0.00568 months <br />) | |
| Opened: | Steve Smith 17:51 Mar 18, 2005 |
| NRC Officer: | Bill Gott |
| Last Updated: | Mar 18, 2005 |
| 41502 - NRC Website
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Unit 1 | |
|---|---|
| Reactor critical | Critical |
| Scram | No |
| Before | Power Operation (100 %) |
| After | Power Operation (70 %) |
WEEKMONTHYEARENS 506002014-11-06T18:16:0006 November 2014 18:16:00
[Table view]10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Technical Specification Required Shutdown Due to Dropped Control Element Assembly ENS 496012013-12-03T06:24:0003 December 2013 06:24:00 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Tech Spec Required Shutdown Due to Dropped Control Element Assembly ENS 442742008-06-06T06:56:0006 June 2008 06:56:00 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Tech Spec Required Shutdown Due to Leak in Safety Injection Tank Vent Line ENS 438042007-11-24T05:26:00024 November 2007 05:26:00 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Technical Specification Required Plant Shutdown Due to Inoperable Load Sequencer ENS 437362007-10-22T10:11:00022 October 2007 10:11:00 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Shutdown Due to Inoperable Steam Driven Auxiliary Feedwater Pump ENS 431732007-02-19T21:57:00019 February 2007 21:57:00 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Unit 2 Performed a Ts Required Shutdown ENS 428472006-09-19T08:05:00019 September 2006 08:05:00 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition, 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Pressurizer Heater Capacity Less than Tech Spec Limit ENS 424872006-04-10T19:33:00010 April 2006 19:33:00 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Unit 2 Entered a Ts Required Shutdown Due to Inoperable Auxiliary Feedwater Pumps ENS 420502005-10-11T23:02:00011 October 2005 23:02:00 10 CFR 50.72(b)(3)(v)(B), Loss of Safety Function - Remove Residual Heat, 10 CFR 50.72(b)(3)(v)(D), Loss of Safety Function - Mitigate the Consequences of an Accident, 10 CFR 50.72(b)(3)(ii)(B), Unanalyzed Condition, 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Tech Spec Required Shutdown of Both Unit 2 and 3 ENS 419392005-08-22T23:05:00022 August 2005 23:05:00 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Technical Specification Shutdown Due to Core Protection Calculator System (Cpcs) Software Not Consistent with System Design Requirements. ENS 419132005-08-12T07:19:00012 August 2005 07:19:00 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Plant Entered Lco Action Statement 3.8.1 to Be in Mode 5 Due to Unit 1 "B" Diesel Gen. Being Declared Inoperable ENS 415022005-03-18T22:00:00018 March 2005 22:00:00 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Technical Specification Required Shutdown Due to Inoperable Diesel Generator ENS 413892005-02-09T08:04:0009 February 2005 08:04:00 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown Technical Specifications Required Shutdown Due to Loss of Normal and Alternate Power to Safety Bus ENS 405032004-02-03T22:35:0003 February 2004 22:35:00 10 CFR 50.72(b)(2)(i), Tech Spec Required Shutdown, 10 CFR 50.72(b)(3)(ii)(A), Seriously Degraded Technical Specification Required Shutdown Due to Rcs Pressure Boundary Leakage 2014-11-06T18:16:00 | |