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Category:REPORTABLE OCCURRENCE REPORT (SEE ALSO AO LER)
MONTHYEARML20195F5911998-09-11011 September 1998 Special Rept:On 980812,addl Unseated Wires Were Discovered. Cause Is Unknown at Present Time.Util Evaluated Number of Unseated/Ineffective Wires & Determined Effect on Containment Structural Integrity.Commitments,Encl ML20247F7711998-05-0808 May 1998 Special Rept:On 980403 & 980503 Seismic Monitoring Sys Was Declared Inoperable.Caused by 5-volt Power Supply & Regulator Card Failure.Imd & Sys Engineering Are Continuing to Identify & Resolve Problems So Sys Can Be Operable ML20217D5131997-09-26026 September 1997 Special Rept:On 970918,moisture Content in Grease Samples Exceeded Maximum 10% by Weight.Caused by Ground Water Intrusion.Engineering Evaluation Performed & Insp of Tendons for Water Will Be Done on Annual Basis ML20149H7271997-07-18018 July 1997 Special Rept:On 970711,abnormal Containment of Tendon Degradation Was Noted.Cause Indeterminate.Will Perform Addl Inspections of Tendon H4ED to Monitor Apparent Addl Degradation.Calculation Re Subj Tendon Encl ML20135F3321997-03-0404 March 1997 Special Rept:On 970303,Braidwood Auxiliary Bldg Vent Stack Wide Range Gas Monitor Was Inoperable for Greater than Seven Days.Caused by Removing Monitoring from Operation to Perform 18-month Channel Calibr.Calibr Was Completed ML20129C8191996-10-0808 October 1996 Special Rept:On 960826,Unit 1 Began Receiving Loose Parts Alarm in Mcr.Caused by C Loop Cold Leg Loop Stop Isolation Valve.Se Performed by Westinghouse ML20057F3961993-10-0808 October 1993 Ro:On 930928,Train B DG Valid Failure Occurred,Causing Annunciators 2-22-C8 & 2-22-D6 to Alarm Simultaneously Due to Blown Fuses 27 & 29.Caused by Relay W/Shorted Circuit. Relay W/Shorted Circuit Replaced W/Bench Tested Relay ML20118B5361992-09-25025 September 1992 Special Rept:On 920913,auxiliary Bldg Vent Stack wide-range Gas Monitor Declared Inoperable.Caused by Need to Perform Instrument Maint Surveillance Procedure.Nuclear Work Request Generated to Replace Failed Printed Circuit Board ML20099K2941992-08-18018 August 1992 Ro:On 920807,auxiliary Bldg Vent Stack wide-range Noble Gas Monitor Declared Inoperable Due to Inability to Pass Source Check.Caused by Failure of High Voltage Power Supply. Original Detector Reinstalled After Addl Failure ML20102B1431992-07-14014 July 1992 Special Rept:On 920610,DG 2A Output Breaker Closed, Resulting in Parallel Operation of DG 2A to Sys Grid & Causing DG Trip.Caused by Reverse Power Condition Due to Operator Error.Surveillance Successfully Completed ML20094K1251992-03-11011 March 1992 Ro:On 920212,diesel Generator 1A Failed to Attain Rated Speed & Voltage within 10 & Declared Inoperable.Caused by Air Leak in Air Control Sys Which Positions Fuel Racks in Full Fuel Position.Test Frequency Increased ML20086A2371991-11-12012 November 1991 Special Rept:On 911026,auxiliary Bldg Vent Stack wide-range Noble Gas Monitor Declared Inoperable & Removed from Svc for More than 7 Days.Caused by Need to Perform 18-month Channel Calibr.Channel Returned to Operable Status on 911107 ML20077B5751991-04-30030 April 1991 Special Rept:On 890724,seismic Monitoring Sys Declared Inoperable to Facilitate Relocation of Free Field Monitor. Efforts to Troubleshoot & Repair Sys Unsuccessful.Schedule for Restoration of Sys Listed ML20066F7191990-12-24024 December 1990 Special Rept:On 901102,sensor Channel Malfunctioned.Cause Unknown.Sensor Channel Will Be Repaired by Next Refueling Outage (Mar 1991) ML20065R8211990-12-13013 December 1990 RO:901114,during Performance of Monthly Operability Surveillance of Diesel Generator 2A,noted That Voltage Indication on Panel Appeared to Be Erroneous.Caused by Failure of Fuse.Fuse Replaced ML20245A8611989-04-14014 April 1989 Ro:On 890215,diesel Generator 1DG01KB Started in Performance of Monthly Operability Surveillance.Generator Came Up to Speed But Immediately Voltage & Frequency Indications Malfunctioned.Caused by Short in Strip Chart Recorder ML20245D8721989-04-14014 April 1989 Ro:On 890215,diesel Generator Voltage & Frequency Indications Malfunctioned.Caused by Blown Fuse in Strip Chart Recorder.Generator Run Manually Terminated & Fuse Replaced ML20196E2341988-11-29029 November 1988 Special Rept:On 881020,discovered That Sensor Channels LM001 & LM009 Were in Low Alarm.Caused by Fraying of Insulated Fibre Jacket of Microdot Connector Cable.Sensor Channels Replaced ML20154E8931988-09-0909 September 1988 Ro:On 880803,diesel Generator 2A Began Losing Speed Upon Entering Test Mode During Monthly Operability Surveillance. Caused by Abnormally High Resistance in Normally Closed Test Mode Contacts of 4EX3 Relay ML20235G8841987-07-0101 July 1987 Special Rept:On 870614,wide Range Gas Monitor (WRGM) Failed Automatic Check Source Test on High Range detector,1PC330. Check Source Damaged During Repairs.Parts & Installation of New Check Sorce Expected to Be Completed by 870715 ML20212K4601987-02-0303 February 1987 Special Rept:On 870106,PORV 1RY455A Lifted for 2 S.Caused by Rapid Increase of RCS Temp When Reactor Cooling Pump 1C Started.Opening PORV Terminated Pressure Transient.On 870112,bubble Formed in Pressurizer to Prevent Recurrence ML20212H3511987-02-0303 February 1987 Ro:On 861209,diesel Generator 1DG01KB Output Breaker Did Not Close on Signal from Control Room.Breaker Circuitry & Linkages Inspected.Following Successful Surveillance Run, Diesel Generator Declared Operable on 861210 1998-09-11
[Table view] Category:TEXT-SAFETY REPORT
MONTHYEARML20217G9961999-10-14014 October 1999 SER Accepting First 10-year Interval Inservice Insp Requests for Relief for Plant,Units 1 & BW990066, Monthly Operating Repts for Sept 1999 for Braidwood Station, Units 1 & 2.With1999-09-30030 September 1999 Monthly Operating Repts for Sept 1999 for Braidwood Station, Units 1 & 2.With ML20217P6351999-09-29029 September 1999 Non-proprietary Rev 6 to HI-982083, Licensing Rept for Spent Fuel Rack Installation at Byron & Braidwood Nuclear Stations ML20217A1691999-09-22022 September 1999 Part 21 Rept Re Engine Sys,Inc Controllers,Manufactured Between Dec 1997 & May 1999,that May Have Questionable Soldering Workmanship.Caused by Inadequate Personnel Training.Sent Rept to All Nuclear Customers ML20212A7441999-09-10010 September 1999 Safety Evaluation Concluding That Alternatives Contained in Relief Request 12R-07 Provide Acceptable Level of Quality & Safety BW990056, Monthly Operating Repts for Aug 1999 for Braidwood Station, Units 1 & 2.With1999-08-31031 August 1999 Monthly Operating Repts for Aug 1999 for Braidwood Station, Units 1 & 2.With ML20210R6421999-08-13013 August 1999 ISI Outage Rept for A2R07 ML20210U8111999-08-0404 August 1999 SER Granting Licensee Relief Requests VR-1,VR-3 & Portion of VR-2 Pursuant to 10CFR50.55a(a)(3)(ii).Relief Request VR-4 Does Not Require Explicit NRC Approval Because Relief Applies to Valves Not Required by 10CFR50.55a BW990048, Monthly Operating Repts for Jul 1999 for Braidwood Station, Units 1 & 2.With1999-07-31031 July 1999 Monthly Operating Repts for Jul 1999 for Braidwood Station, Units 1 & 2.With ML20210K9861999-07-30030 July 1999 Safety Evaluation Accepting Licensee 60-day Response to GL 96-05, Periodic Verification of Design-Basis Capability of Safety-Related Movs ML20216D3841999-07-12012 July 1999 Revised NFM9900022, Braidwood Unit 2 Cycle 8 COLR in ITS Format & W(Z) Function M990002, Revised NFM9900022, Braidwood Unit 2 Cycle 8 COLR in ITS Format & W(Z) Function1999-07-12012 July 1999 Revised NFM9900022, Braidwood Unit 2 Cycle 8 COLR in ITS Format & W(Z) Function BW990038, Monthly Operating Repts for June 1999 for Braidwood Station, Units 1 & 2.With1999-06-30030 June 1999 Monthly Operating Repts for June 1999 for Braidwood Station, Units 1 & 2.With BW990029, Monthly Operating Repts for May 1999 for Braidwood Stations, Units 1 & 2.With1999-05-31031 May 1999 Monthly Operating Repts for May 1999 for Braidwood Stations, Units 1 & 2.With ML20209H7481999-05-31031 May 1999 Revised Monthly Operating Repts for May 1999 for Braidwood Station,Units 1 & 2 ML20207B6481999-05-25025 May 1999 SER Accepting Revised SGTR Analysis for Byron & Braidwood Stations.Revised Analysis Was Submitted to Support SG Replacement at Unit 1 of Each Station ML20195B2591999-05-19019 May 1999 Rev 66a to CE-1-A,consisting of Proposed Changes to QAP for Dnps,Qcs,Znps,Lcs,Byron & Braidwood Stations BW990021, Monthly Operating Repts for Apr 1999 for Braidwood Station, Units 1 & 2.With1999-04-30030 April 1999 Monthly Operating Repts for Apr 1999 for Braidwood Station, Units 1 & 2.With BW990016, Monthly Operating Repts for Mar 1999 for Braidwood Generating Station,Units 1 & 2.With1999-03-31031 March 1999 Monthly Operating Repts for Mar 1999 for Braidwood Generating Station,Units 1 & 2.With ML20205C5101999-03-21021 March 1999 Revised Safety Evaluation Supporting Improved TS Amends Issued by NRC on 981222 to FOLs NPF-37,NPF-66,NPF-72 & NPF-77.Revised Pages Include Editorial Corrections ML20196A0721999-03-16016 March 1999 Cycle 8 COLR in ITS Format & W(Z) Function ML20207J4371999-03-0808 March 1999 ISI Outage Rept for A1R07 ML20204H9941999-03-0303 March 1999 Non-proprietary Rev 4 to HI-982083, Licensing Rept for Spent Fuel Rack Installation at Byron & Braidwood Nuclear Stations BW990010, Monthly Operating Repts for Feb 1999 for Braidwood Generating Station,Units 1 & 2.With1999-02-28028 February 1999 Monthly Operating Repts for Feb 1999 for Braidwood Generating Station,Units 1 & 2.With ML20206U9011999-02-15015 February 1999 COLR for Braidwood Unit 2 Cycle 7. Page 1 0f 13 of Incoming Submittal Was Not Included BW990004, Monthly Operating Repts for Jan 1999 for Braidwood Generating Station,Units 1 & 2.With1999-01-31031 January 1999 Monthly Operating Repts for Jan 1999 for Braidwood Generating Station,Units 1 & 2.With ML20205M7061998-12-31031 December 1998 Unicom Corp 1998 Summary Annual Rept. with BW990001, Monthly Operating Repts for Dec 1998 for Braidwood Generating Station,Units 1 & 2.With1998-12-31031 December 1998 Monthly Operating Repts for Dec 1998 for Braidwood Generating Station,Units 1 & 2.With ML20206B4001998-12-31031 December 1998 Annual & 30-Day Rept of ECCS Evaluation Model Changes & Errors for Byron & Braidwood Stations ML20206U9081998-12-17017 December 1998 Cycle 8 COLR in ITS Format & W(Z) Function BW980076, Monthly Operating Repts for Nov 1998 for Braidwood Generating Station,Units 1 & 2.With1998-11-30030 November 1998 Monthly Operating Repts for Nov 1998 for Braidwood Generating Station,Units 1 & 2.With ML20196A4191998-11-19019 November 1998 Safety Evaluation Accepting QA TR CE-1-A,Rev 66 Re Changes in Independent & Onsite Review Organization by Creating NSRB ML20195D3561998-10-31031 October 1998 Monthly Operating Repts for Oct 1998 for Braidwood Generating Station,Units 1 & 2.With ML20155B6711998-10-26026 October 1998 Safety Evaluation Accepting Requests for Relief Associated with Second 10-yr Interval ISI Program Plan ML20207H7671998-10-0505 October 1998 Rv Weld Chemistry & Initial Rt Ndt ML20154D4401998-10-0202 October 1998 Safety Evaluation Authorizing Second 10-yr Interval ISI Program Request for Relief 12R-30 for Plant,Units 1 & 2 ML20155C2601998-09-30030 September 1998 Monthly Operating Repts for Sept 1998 for Braidwood Generating Station,Units 1 & 2 ML20195F5911998-09-11011 September 1998 Special Rept:On 980812,addl Unseated Wires Were Discovered. Cause Is Unknown at Present Time.Util Evaluated Number of Unseated/Ineffective Wires & Determined Effect on Containment Structural Integrity.Commitments,Encl ML20196B3711998-09-0808 September 1998 Cycle 8 Operating Limits Rept (Olr) ML20151X6671998-08-31031 August 1998 Monthly Operating Repts for Aug 1998 for Braidwood Generating Station,Units 1 & 2.With ML20238F3281998-08-31031 August 1998 SER Approving Second 10-year Interval Inservice Insp Program Request for Relief 12R-14 for Braidwood Station,Units 1 & 2 ML20237E2331998-08-21021 August 1998 Revised Pages of Section 20 of Rev 66 to CE-1-A, QA Topical Rept ML20237A1091998-07-31031 July 1998 Monthly Operating Repts for July 1998 for Braidwood Generating Station,Unit 1 & 2 ML20236N7001998-06-30030 June 1998 Monthly Operating Repts for June 1998 for Braidwood Generating Station,Units 1 & 2 ML20198A0151998-06-18018 June 1998 10CFR50.59 Summary Rept 960619 Through 980618, Vols I & Ii,Consisting of Descriptions & SE Summaries for Changes to Procedural UFSAR Changes,Tests & Experiments & FP Rept.Without Fp,Rept ML20249A5451998-05-31031 May 1998 Monthly Operating Repts for May 1998 for Braidwood Generating Station Units 1 & 2 ML20247F7711998-05-0808 May 1998 Special Rept:On 980403 & 980503 Seismic Monitoring Sys Was Declared Inoperable.Caused by 5-volt Power Supply & Regulator Card Failure.Imd & Sys Engineering Are Continuing to Identify & Resolve Problems So Sys Can Be Operable ML20247L7591998-04-30030 April 1998 Monthly Operating Repts for Apr 1998 for Braidwood Generating Station,Units 1 & 2 ML20217K6331998-04-20020 April 1998 Safety Evaluation Accepting Methodology & Criteria Used in Generating Flaw Evaluation Charts for RPV of Braidwood IAW Section XI of ASME Code ML20216C6621998-03-31031 March 1998 Monthly Operating Repts for Mar 1998 for Braidwood Generating Station,Units 1 & 2 1999-09-30
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- on.r - %.C %.== PalCg11YR0J11N O J Address Meply to: Post Omco Box 767
,/ CNcago,libros 80680 0767 'W September 9, 1988 [h _a,- D 4
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nLc .1 Mr. A. Bert Dr.vis FIL%
Regional A&ninistrator -
U.S. Nuclear Regulatory Comunission \) g
, Region !!! j 799 Roosevelt Road '
Glen Ellyn, IL. 60137 i, Subject Braidwood Station Unit 2 Diesel Generator 2DG01KA Failure i MRC Dochet Mo. 50-451 i Reference (a): NUREG-1276, Technical Specification, dated July, 1987 i (b): September 1, 1988 S.C. Hunsader letter to !
A.S. Davis Dear Mr. Davist b l Section 4.8.1.1.3 of reference (a) requires that all diesel generator failures, valid or non-valid, be reported to the NRC pursuant to Specification (
, 6.9.2. The enclosure provides the report that addresses one valid and three [
j invalid test failures experienced on diesel generator 2DG01KA. '
)
' Reference (b) is the most recent report addresaing diesel generator !
failures, issued per Section 4.8.1.1.3. j j Please direct any questions concerning this matter to this office.
Very truly yours, l f
S. C. Hunsador Nuclear Licensing Ackninistrator
/klj cc 5. Sands-NRR i Braidwood Resident Inspector [
NRC Document Control Desk l
/
L 4 5096K .
o I i
j l 8809190176 880909 !
f ADOCK 05000457
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2A D/G FAILURE REPORT On August 3, 1988 at 0937, the 2A Diesel Generator was started, using an emergency start signal, in performance of the monthly operability surveillance. Following a successful start, the Operator transferred the Diesel / Generator from the emergency mode to the test mode to begin synchronizing to the grid. Immediately upon entering the test mode, the Diesel Generator began losing speed. At 280 rpm the 2A Diesel Generator tripped on "Incomplete Sequence".
Three troubleshooting / maintenance runs were attempted during the subsequent troubleshooting. In each attempt the Diesel Generator speed began to decrease after accelerating to 350-400 rpm. At 280 rpm the Diesel Generator tripped on Incomplete Sequence. All three attempts were performed in the test mode.
Troubleshooting identified the cause of the speed loss, and subsequent Incomplete Sequence trips, to be the result of &n abnormally high resistance in the normally closed test mode contacts of the 4EX3 relay. These contacts are in series with the Motor Operated Potentiometer (HOP) which provides the electronic governor's speed reference signal in the test mode. The HOP is used to change the Diesel Generator's frequency when synchronizing to the grid or to change the Diesel Generator's load when synchronized.
The increased resistance in this circuit caused the Diesel Generator to reduce speed. When the Diesel Generator is in the emergency mode, the HOP circuit is open and the speed reference signal is provided by a separate resistor bank preset to 60 Hertz. The Emergency Automatic circuit was functional as evidenced by the successful Emergency Mode start.
The 4EX3 relay was removed by Electrical Maintenance personnel, the contacts were cleaned a:d the relay was reinstalled. Two additional troubleshooting runs were performed during which the Diesel Generator functioned properly. At 0225 on 8-5-88 the Diesel Generator was started to demonstrate Operability, using the same surveillance previously used during the August 3, 1988 failure. At 0352 the diesel Generator was shutdown after successfully completing the operability surveillance. At 0451 on 8-5-08, the 2A Diesel Generator LCOAR was exited. The 2A Diesel Generator was inoperable for 43 hours4.976852e-4 days <br />0.0119 hours <br />7.109788e-5 weeks <br />1.63615e-5 months <br /> and 14 minutes.
The August 3, 1988 failure is conservatively classified as a valid failure. Regulatory Guide 1.108 position C.2.e.2 provides for classifying failures as invalid for unsuccessful start and load attempts that can definitely be attributed to the malfunction of equipment that is not operative in the emergency operating mode.
The dirty contacts which resulted in this failure are not operative in the emergency operating mode. The 2A Olesel Generator did start upon receipt of the emergency start signal and would have loid1d successfully had an accident situation occured. Considering the worst case accident, if an operator attempted to transfer load from the 2A diesel to an offsite power source, the 2A diesel would have tripped and the remaining redundant train would mitigate the (6735z/2)
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accident consequences. Diesel Generator failures shall continue to be evaluated on a case by case basis per the guidance provided in Regulatory Guide 1.108. ,
The 2A Diesel Generator has had 2 valid failures in the 19 valid tests ',ince the completion of pre-operational testing. The 2A Diesel Generator is currently being tested weekly in accordance with Technical Specification 4.8.1.1.2.
Similar 4EX3 related failures were previously identified in the letters to the U.S. NRC dated April 6,1988, Subject - Braidwood.
Station Unit 1 Diesel Generator 10G0lKB Failure NRC Docket No.
50-456, and October 5, 1987, Subject - Braidwood Station Unit i Diesel Generatot IDG01KA Failure, NRC Docket No. 50-456. The modification request to replace the 4EX3 relays with relays having less contact resistance and more stable characteristics is being tracked by AIR No. 4356-200-97-28401. The designs for the installation of the new relays are cot;1ete and the procurement of the necessary materials is in progress. Upon receipt of the materials, each Diesel Generator's 4EX3 relay will be replaced at '
the first outage of sufficient duration.
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(6735z/3)
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