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Category:LICENSEE EVENT REPORT (SEE ALSO AO
MONTHYEARML20045B3551993-06-11011 June 1993 LER 93-001-00:on 930429,refueling Jib Crane Moved in Vicinity of Spent Fuel Pool Using vendor-supplied Lifting Eye in Violation of NUREG-0612.Caused by Failure to Identify Crane as Heavy Load.Meetings held.W/930611 Ltr ML20024G7171991-04-22022 April 1991 LER 91-001-00:on 910324,RB Normal Ventilation Sys (Rbnvs) Outboard Exhaust Valve Closed for No Apparent Reason.Cause Inconclusive.Sys Restored to Normal Lineup & Rbnvs Outboard Valve Will Be Stroked on Routine basis.W/910422 Ltr ML20028H0231990-09-28028 September 1990 LER 90-007-00:on 900907,unplanned Actuation of ESF Sys Occurred During I&C Surveillance Test.Caused by Inadequate procedure.SP44.650.16 Revised to Require That Leads Lifted & Individually separated.W/900928 Ltr ML20012C5131990-03-16016 March 1990 LER 86-029-02:on 860718,19,21 & 870508,loss of Reactor Protection Sys Power Occurred Due to Spurious Tripping of Alternate Feed EPA Breakers.Caused by Low Output Voltage of Alternate Feed Transformer.Output adjusted.W/900316 Ltr ML20006E1571990-02-0909 February 1990 LER 90-001-00:on 900117,unplanned Actuation of ESF Reactor Bldg Standby Ventilation Sys B Occurred,Causing Interlocking Relays in Control Circuits to Deenergize.Caused by Transient Voltage Dip.Procedures Re Bus Loads modified.W/900209 Ltr ML19354D8331990-01-12012 January 1990 LER 89-011-00:on 891222,unplanned Actuation of ESF Primary Containment Isolation Sys Occurred When Performing Sys Layup Implementation Package for Hpci.Caused by Inadequate Procedure.Breaker Positions changed.W/900112 Ltr ML20005F8641990-01-11011 January 1990 LER 89-010-00:on 891212,unplanned Actuation of ESF Control Room Air Conditioning Train a Occurred.Caused by Removal of Leads from Relay During Test to Prevent ESF Sys Actuations. Electrical Relay Replaced & Wiring Mod made.W/900111 Ltr ML20011D2371989-12-15015 December 1989 LER 89-009-00:on 891115,notification Received of Potential Failure Mechanism of Four 3-way Solenoid Operated Pilot Valves.Caused by Incorrect Mounting of Valves.Valves Remounted Vertically & Field Walkdown done.W/891215 Ltr ML19332C5591989-11-15015 November 1989 LER 89-008-00:on 891016,control Room Alarms Received Indicating Fire Pump Had Started & Deluge Valve Had Opened. Caused by Actuation of Manual Pull Station.Deluge Sys Restored to Normal & Personnel interviewed.W/891115 Ltr 1993-06-11
[Table view] Category:RO)
MONTHYEARML20045B3551993-06-11011 June 1993 LER 93-001-00:on 930429,refueling Jib Crane Moved in Vicinity of Spent Fuel Pool Using vendor-supplied Lifting Eye in Violation of NUREG-0612.Caused by Failure to Identify Crane as Heavy Load.Meetings held.W/930611 Ltr ML20024G7171991-04-22022 April 1991 LER 91-001-00:on 910324,RB Normal Ventilation Sys (Rbnvs) Outboard Exhaust Valve Closed for No Apparent Reason.Cause Inconclusive.Sys Restored to Normal Lineup & Rbnvs Outboard Valve Will Be Stroked on Routine basis.W/910422 Ltr ML20028H0231990-09-28028 September 1990 LER 90-007-00:on 900907,unplanned Actuation of ESF Sys Occurred During I&C Surveillance Test.Caused by Inadequate procedure.SP44.650.16 Revised to Require That Leads Lifted & Individually separated.W/900928 Ltr ML20012C5131990-03-16016 March 1990 LER 86-029-02:on 860718,19,21 & 870508,loss of Reactor Protection Sys Power Occurred Due to Spurious Tripping of Alternate Feed EPA Breakers.Caused by Low Output Voltage of Alternate Feed Transformer.Output adjusted.W/900316 Ltr ML20006E1571990-02-0909 February 1990 LER 90-001-00:on 900117,unplanned Actuation of ESF Reactor Bldg Standby Ventilation Sys B Occurred,Causing Interlocking Relays in Control Circuits to Deenergize.Caused by Transient Voltage Dip.Procedures Re Bus Loads modified.W/900209 Ltr ML19354D8331990-01-12012 January 1990 LER 89-011-00:on 891222,unplanned Actuation of ESF Primary Containment Isolation Sys Occurred When Performing Sys Layup Implementation Package for Hpci.Caused by Inadequate Procedure.Breaker Positions changed.W/900112 Ltr ML20005F8641990-01-11011 January 1990 LER 89-010-00:on 891212,unplanned Actuation of ESF Control Room Air Conditioning Train a Occurred.Caused by Removal of Leads from Relay During Test to Prevent ESF Sys Actuations. Electrical Relay Replaced & Wiring Mod made.W/900111 Ltr ML20011D2371989-12-15015 December 1989 LER 89-009-00:on 891115,notification Received of Potential Failure Mechanism of Four 3-way Solenoid Operated Pilot Valves.Caused by Incorrect Mounting of Valves.Valves Remounted Vertically & Field Walkdown done.W/891215 Ltr ML19332C5591989-11-15015 November 1989 LER 89-008-00:on 891016,control Room Alarms Received Indicating Fire Pump Had Started & Deluge Valve Had Opened. Caused by Actuation of Manual Pull Station.Deluge Sys Restored to Normal & Personnel interviewed.W/891115 Ltr 1993-06-11
[Table view] Category:TEXT-SAFETY REPORT
MONTHYEARML20140G4481997-05-0101 May 1997 Part 21 Rept Re Potential Defect in Component of Dsrv & Dsr Enterprise Standby Diesel Generator Sys.Recommends That Springs Be Inspected on Periodic Basis,Such as During Refueling Outages ML20135D8011996-11-26026 November 1996 Part 21 Rept Re Two Safety Related Valves Supplied by Velan Valve Corp Were Not in Compliance W/Originally Supplied QA Documentation.Returned Valves to Velan in May 1996 & on 961120 Velan Advised That Valves Had Been Misplaced ML20080G4691995-01-26026 January 1995 Record of Telcon W/Nrc & Licensees 950126 to Clarify Position Re Dispositioning of Exempt Sources Listed in Section 6.3.3 of Shoreham Termination Survey Final Rept Dtd Oct 1994 ML20069F0001994-01-24024 January 1994 Vols 1-4 to Shoreham Decommissioning Project Termination Survey Final Rept ML20058K3841993-12-0909 December 1993 Part 21 Rept Re Potential Defect in Component of Dsrv & Dsr Enterprise Standby DG Sys,Regarding Potential Problem W/ Subcover Assembled Atop Power Head ML20057F2261993-09-30030 September 1993 Safety Evaluation Supporting Exemption Request from Requirements of 10CFR50.54(q) for License NPF-82 ML20056C7181993-07-14014 July 1993 SE Supporting Amend 10 to License NPF-82 ML20045B3551993-06-11011 June 1993 LER 93-001-00:on 930429,refueling Jib Crane Moved in Vicinity of Spent Fuel Pool Using vendor-supplied Lifting Eye in Violation of NUREG-0612.Caused by Failure to Identify Crane as Heavy Load.Meetings held.W/930611 Ltr ML20045C8881993-06-0808 June 1993 Vols 1 & 2 to Refueling Jib Crane 1T31-CRN-008A Incident Root Cause Analysis. W/One Oversize Encl ML20044C1181993-02-28028 February 1993 Shoreham Nuclear Power Station Updated Decommissioning Plan. ML20128P6451993-02-28028 February 1993 Snps Decommissioning Project Termination Survey Final Rept for Steam Turbine Sys (N31) ML20128P7431993-02-19019 February 1993 Rev 3 to 93X027, Nuclear QA Surveillance Rept ML20127H2301993-01-15015 January 1993 Part 21 Rept Re Potential Defeat in Component of Dsrv & Dsr Enterprise Standby DG Sys.Starting Air Distributor Housing Assemblies Installed as Replacement Parts at Listed Sites ML20126B0421992-12-17017 December 1992 Final Part 21 Rept Re Potential Problem W/Steel Cylinder Heads.Initially Reported on 921125.Caused by Inadequate Cast Wall Thickness at 3/4-inch-10 Bolt Hole.Stud at Location Indicated on Encl Sketch Should Be Removed ML20125C7161992-12-0707 December 1992 Part 21 Rept Re Possibility for Malfunction of Declutching Mechanisms in SMB/SB-000 & SMB/SB/SBD-00 Actuators. Malfunction Only Occurs During Seismic Event.Balanced Levers May Be Purchased from Vendor.List of Affected Utils Encl ML20127P5861992-11-23023 November 1992 Followup to 921005 Part 21 Rept Re Potential Defect in SB/SBD-1 Housing Cover Screws.Procedure Re Replacement of SBD-1 Spring Cover Bolts Encl.All Fasteners Should Be Loosened & Removed.List of Affected Utils Encl ML20128B9641992-10-31031 October 1992 Rev 0 to Shoreham Decommissioning Project Termination Survey Plan ML20118B4391992-09-11011 September 1992 Part 21 Rept Re Degradation in Abb Type 27N Undervoltage Relays Used in Electrical Switchgear.Recommends That Users Review Applications Requiring Exposures Greater than 1E03 Rads TID W/Time Delay Function Option ML20099H5781992-07-31031 July 1992 Rev 4 to Shoreham Defueled Sar ML20114A6311992-07-28028 July 1992 Shoreham Decommissioning Plan ML20101K5791992-06-25025 June 1992 Long Island Power Authority Shoreham Decommissioning Project,Shoreham Nuclear Power Station,Technical Rept on Water Processing & Water Mgt Activities for Reactor Pressure Vessel & Wet Cutting Station ML20094L1271992-03-13013 March 1992 Amend 1 to Part 21 Rept 159 Re Potential Defect in Power Cylinder Liner.Initially Reported on 920115.Caused by Liner/ Block Fit & Localized Matl Microstructure.All Drawings & Specs Revised to Address Matl Design Requirements ML20082M5081991-08-26026 August 1991 Rev 3 to Shoreham Defueled Sar PM-91-125, Monthly Operating Rept for Jul 1991 for Shoreham Nuclear Power Station1991-07-31031 July 1991 Monthly Operating Rept for Jul 1991 for Shoreham Nuclear Power Station PM-91-112, Monthly Operating Rept for Jun 1991 for Shoreham Nuclear Power Station1991-06-30030 June 1991 Monthly Operating Rept for Jun 1991 for Shoreham Nuclear Power Station PM-91-075, Monthly Operating Rept for Apr 1991 for Shoreham Nuclear Power Station1991-04-30030 April 1991 Monthly Operating Rept for Apr 1991 for Shoreham Nuclear Power Station ML20024G7171991-04-22022 April 1991 LER 91-001-00:on 910324,RB Normal Ventilation Sys (Rbnvs) Outboard Exhaust Valve Closed for No Apparent Reason.Cause Inconclusive.Sys Restored to Normal Lineup & Rbnvs Outboard Valve Will Be Stroked on Routine basis.W/910422 Ltr SNRC-1806, Revised Pages 2 & 6 to Encl a of 10CFR50.59 Annual Rept for 19901991-04-15015 April 1991 Revised Pages 2 & 6 to Encl a of 10CFR50.59 Annual Rept for 1990 PM-91-058, Monthly Operating Rept for Mar 1991 for Shoreham Nuclear Power Station1991-03-31031 March 1991 Monthly Operating Rept for Mar 1991 for Shoreham Nuclear Power Station PM-91-037, Monthly Operating Rept for Feb 1991 for Shoreham Nuclear Power Station1991-02-28028 February 1991 Monthly Operating Rept for Feb 1991 for Shoreham Nuclear Power Station PM-91-016, Monthly Operating Rept for Jan 1991 for Shoreham Nuclear Power Station1991-01-31031 January 1991 Monthly Operating Rept for Jan 1991 for Shoreham Nuclear Power Station SNRC-1797, 10CFR 50.59 Annual Rept of Facility Changes,Procedure Changes,Tests & Experiments for Jan-Dec 19901990-12-31031 December 1990 10CFR 50.59 Annual Rept of Facility Changes,Procedure Changes,Tests & Experiments for Jan-Dec 1990 SNRC-1794, Shoreham Nuclear Power Station Annual Operating Rept,19901990-12-31031 December 1990 Shoreham Nuclear Power Station Annual Operating Rept,1990 SNRC-1799, Lilco 1990 Annual Rept1990-12-31031 December 1990 Lilco 1990 Annual Rept ML20069Q3901990-12-31031 December 1990 Shoreham Nuclear Power Station Decommissioning Plan. (Filed in Category P) ML20028H0231990-09-28028 September 1990 LER 90-007-00:on 900907,unplanned Actuation of ESF Sys Occurred During I&C Surveillance Test.Caused by Inadequate procedure.SP44.650.16 Revised to Require That Leads Lifted & Individually separated.W/900928 Ltr ML20056A2001990-07-31031 July 1990 Safety Evaluation Supporting Amend 6 to License NPF-82 PM-90-097, Monthly Operating Rept for June 1990 for Shoreham Nuclear Power Station1990-06-30030 June 1990 Monthly Operating Rept for June 1990 for Shoreham Nuclear Power Station ML20055E3911990-06-25025 June 1990 Safety Evaluation Supporting Amend 5 to License NPF-82 PM-90-083, Monthly Operating Rept for May 1990 for Shoreham Nuclear Power Station1990-05-31031 May 1990 Monthly Operating Rept for May 1990 for Shoreham Nuclear Power Station 05000322/LER-1988-0151990-05-16016 May 1990 LER 88-015-02:on 880916,seismic Monitoring Instrumentation, Including Peak Acceleration Recorders,Removed from Svc for More than 30 Days Due to Corrosion on Scratch Plates.Cover Gasket Replaced & Thermal Barrier Mount to Be Installed 05000322/LER-1986-0391990-05-16016 May 1990 LER 86-039-01:on 861006,unplanned Initiation of Reactor Bldg Standby Ventilation Sys Occurred W/All Rods Inserted in Core.Caused by Faulty Design of Retaining Device.Warning Signs Attached to Valve Actuator & Valve Mod Initiated 05000322/LER-1986-0321990-05-16016 May 1990 LER 86-032-01:on 860728,RWCU Isolated on High Differential Flow Sensed by Steam Leak Detection Sys While Placing Filter Demineralizers in Operation.Cause Not Determined. Operating Procedures Revised to Monitor RWCU Sys 05000322/LER-1987-0091990-05-16016 May 1990 LER 87-009-01:on 870203,full Reactor Trip Occurred Due to Perturbation in Ref Leg.Caused by Spurious Low Level Reactor Pressure Vessel Water Level Signal.Existing Level & Pressure Transmitters Replaced W/Newer Models 05000322/LER-1987-0221990-05-16016 May 1990 LER 87-022-01:on 870604,HPCI Test Valve to Condensate Storage Tank,Globe Valve & Hpci/Rcic Test Valve to Condensate Storage Tank Failed to Close Against Sys Operating Pressure.Disc of motor-operated Valve 37 Modified 05000322/LER-1989-0051990-05-16016 May 1990 LER 89-005-01:on 890321,results of Local Leak Rate Test of Core Spray Suction Valve a Determined That Leakage,When Combined W/All Type B & C Penetration Leakages,Exceeded Tech Spec Limit.Caused by Normal Valve Degradation 05000322/LER-1989-0031990-05-16016 May 1990 LER 89-003-01:on 890310,emergency Diesel Generator (EDG) 102 Manually Shutdown During 18-month Surveillance Test Due to Failure of EDG Output Breaker.Cause Not Determined. Replacement Breaker Installed in Cubicle 102-8 05000322/LER-1985-0591990-05-16016 May 1990 LER 85-059-01:on 851219,half Reactor Trip,Full NSSS Shutoff Sys Isolation & Reactor Bldg Standby Ventilation Sys Initiation Occurred Due to Loss of Power to Reactor Protection Sys Bus B.Assembly Breaker Reset 05000322/LER-1987-0351990-05-16016 May 1990 LER 87-035-02:on 871221,880106 & 0330,high Energy Line Break Logic Isolations of RWCU & Main Steam Line Drain Valves Occurred.Caused by Problems W/Temp Monitoring Units. Grounding Scheme Changed & Transformers Rewired 05000322/LER-1988-0031990-05-16016 May 1990 LER 88-003-01:on 880322,unplanned Automatic Initiation of Reactor Bldg Standby Ventilation Sys Side a Occurred During Deenergization of Relay.Caused by Close Placement of Relay Terminals.Wiring Inside Electrical Panels Reworked 1997-05-01
[Table view] |
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February 9, 1990 PM 90-029 l-
-U.S.. Nuclear Regulatory Commission Document' Control-Desk Washington, D.C. 20555
Dear Sir:
l LIn accordance with 10CFR50.73, enclosed is Shoreham Nuclear Power i
- Station's-Licensee. Event Report, LER 90-001.
Sincerely yours,- j i
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~ Jack A.- Notfro Plant Manager
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- Enclosure
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William T.' Russell,--Regional Administrator i Institute of Nuclear Power Operations, Records Center -
American Nuclear Insurers ;
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Shoreham Nuclear power Station Unit 1 0 l5l0l0l0l3 l2l2 i lopl0 l4 Unplanned Actuation of Reactor Building Standby Ventilation System During Test of T--~
Tw e. esA nwne EVENT DAf t 151 LEft NUMSER to) REPORT DATE 17) OTHER F ACILITitS INVO./ED 18)
MONTH DAY YEAR YtAR I'gG 7fy MONTH DAY YEAR ' ACILIT v N AMES DOCnti NUMSERI$)
015lcl0l0l l l nI1 1 17 o n o In nIn h n in 01 2 0 l9 9 l0 0 [5;0 l0 1 0l l l THIS REPORT IS SUDMITTED PURSUANT TO THE RkOUIREMENTS OF 10 CFR l. (Checa one er mere e,,ne ferie .nps (til OPE R ATING . g MODE m 20 402thi to 40 sten to.73telt2Hal 7371N y _
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NAME TELEPHONE NUMSER ARE A COJE '
George D. Schnaars, Operational Compliance Engineer 5l1p 9l2 ; 9; i8 ;3j0j0 I l COMPLETE ONE LINE FOR E ACH COMPONENT F AILURE DESCRISED IN THIS REPORT (136 MA AC. R PORfAB E R PORTA E CAUSE SYSTEM COMPONENT o pn CAUSE SY STE M COMPONENT s M A% AC- pp
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SUPPLEMENTAL REPORT EXPECTED ties MONT k. DAY YEAR SUOMi$$ ION - r Yt$ to, pas eempie,e EXPECTED SUOMISSION DA TEI NO l l l A 1x ACT m,,,a ,e ,*= .me, , e e.,e.-e,*,, ,,,,,,,, ,,,e ,me ,, ,are. ,,,,s., im On January 17, 1990 at 0457~ hours, an unplanned actuation of the Engineered Safety Feature Reactor Building Standby Ventilation System (RBSVS) "B" occurred, This actuation occurred during the performance of a surveillance procedure that tested the ability of Emergency Bus 102 to automatically " fast transfer" from its normal -
to its alternate power supply. The voltage dip during the fast transfer was sufficient to deenergize interlocking relays in the control circuits for 1T46*A0V-35B or 37B (Reactor Building Normal Ventilation Supply and Exhaust Valves). Either one of the A0Vs going closed caused the actuation of RBSVS "B". Testing was stopped and plant management was notified of the event. The event was reportable under 10CFR50.72(b)(2)(ii) and the NRC was notified at
( 0652 hours0.00755 days <br />0.181 hours <br />0.00108 weeks <br />2.48086e-4 months <br />. Corrective actions include changing the surveillance
/ test' procedure to require that if a minimum emergency bus load cannot be achieved, then RBSVS is to be manually initiated.
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- PLAN't_AED_SYSIEM_IDEHilEICAIl0H General Electric - Boiling Water Reactor Energy Industry Identif.ication System (EIIS) codes are identified j- in-the_ text as [xx].
lIDEBIIFICAIIOfLRE_THE EVENT ,
Unplanned actuation of the Engineered Safety Feature Reactor Building Standby Ventilation System (RBSYS)[BH] "B" during a surveillance test. .
Event Date: 01/17/30
. Repo'rt Date: 02/09/90 DONDITIQES PRIOB._ID THE. EVENT Reactor.Defueled - All fuel assemblies stored in the Spent Fuel Pool Mode-Switch - Shutdown RPV Pressure.= 0 psig RPV-Temperature = 85 Degrees F
! . POWER LEVEL - 0 DEliCBIETIQU_QE._IBE_EVIHI On January 17, 1990 Control-Room Operators were performing surveillance test procedure SP 24.301.01,_ Station Power Supply Transfer Test. This test is performed in order to satisfy Technical
- Specifications 4.8.1.1'.1 b and 4.8.1.2. 'The operators were performing' step'58 of this procedure. This step verifies the-operability of the-fast transfer capability of the Emergency Bus 102 switchgear.- At 0457 hours0.00529 days <br />0.127 hours <br />7.556217e-4 weeks <br />1.738885e-4 months <br />, the operators manually tripped the l normal. supply breaker to bus 102 and then verified-that the reserve supply breaker _to~ bus 102 closed automatically as required by the fast transfer scheme. However, during the peri'ormance of this step - <
lan unplanned actuation of the Engineered Safety Feature RBSVG "B" occurred.
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Testing was then stopped and RBSVS "A" and the A and B trains of Control Rnom Air Conditioning were manually initiated. The
. unplanned actuation of an Engineered Safety Feature is reportable per 10CFR50.72(b)(2)(ii). Plant management personnel were notified of the event and the NRC was notified at 0652 hours0.00755 days <br />0.181 hours <br />0.00108 weeks <br />2.48086e-4 months <br />.
CAUSE_DE_IBE EVENI The unplanned actuation of RBSYS "B" was caused by the transient voltage dip on bus 102 which occurred during the fast transfer test of the bus 102 switchgear. Specifically, the voltage dip allowed an ,
interlocking relay to drop out in the control circuit for 1T46*A0V-35B or 37B (Reactor Building Normal Ventilation Supply-and Exhaust Valves). These relays have seal-in contacts that open on relay dropout and prevent them from picking up again after normal voltage is restored. When these relays deenergize they allow their i associated AOV to close (1T46*AOV-35B or 37B) and either AOV closing initiated RBSYS "B".
The fast transfer of an emergency bus from its normal to its alternate power supply in designed to be completed within 10 cycles to prevent-running motors from dropping out of step. Testing determined that this fast transfer is completed in 4.5 to 6 cycles.
This testing was performed while the emergency buses were supplying
. loads consistant with the current plant operating condition.
Additional testing determined that the critical factor in this event is that the magnitude of the voltage dip during the fast transfer is dependent upon the amount of rotating equipment being powered by the bus. For example, during a bus deenergization, the length of I time for the bus voltage to drop low enough for the interlocking' l relays to deenergize was 1 cycle with a bus load of 20 amps. The )
time was 21.5 cycles when additional motors were run to increase the bus load to 140 amps.
Since the emergency bus switchgear complete the fast transfers within'the design requirement, the occurrence of the interlocking relays dropping out (and the RBSVS initiation) is dependent upon the bus-load. The inductive loads being supplied by the bus help E maintain the residual bus voltage during the fast transfer. Without
-sufficient inductive load, the bus voltage decays to a point where the interlocking relays drop out.
The occurrence of an RBSYS initiation during an emergency bus fast ;
transfer test had never been experienced prior to this event. This I is because the previous fast transfer tests were performed when the emergency bus loads were higher than present.
l NRC Penn 306A (649) u-
c, p A -- u... xam..Uuvon, Co g EK767.18 4/3002 LICENSEE EVENT REPORT (LERI IS&"?'Mo',fis" M",J;'5Cli,%T"l# ,Tn"d%'!
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TEXT CONTINUATION 1%"n'"48,"rl*MN!'fe5M'%d'Cn, PAPERWO K RE TION 6 1 O IC '
OF MANAQf MENT AND DVDGET,WASHINGTCE, DC 20603. '
PACILITY . FAME til DOCKET UMSER (2) LER NUMSER (St PAGE (31
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Shoreham Nuclear power Station Unit 1 o.l6jol0l0l3l2l2 9 l0 -
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010 0l4 oF 0 l4 Tur a = w w =ac r assaim ANALYSIS _OE_IBE EVENT >
. There was no safety significance to this event. The plant is shutdown and has been defueled since August of 1989. The operators took the proper corrective actions in response to the RBSYS initiation.
Plant. Systems, including the RBSYS and the Bus 102 switchgear,-
performed as designed.
CORREGIlY.E_AGIl0NS
- 1. Station Procedure 24.301.01, Station Power Supply Transfer Test, has been modified to require operators to start additional rotating equipment so that the emergency bus loads are above a specified minimum load. If this minimum load '
cannot be achieved then the applicable train of RBSVS is to be manually initiated prior to the fast transfer-test of the emergency bus switchgear.
- 2. Station Procedure 23.309.01, 4160 Emergency Bus Distribution, '
has been changed by adding precautions and instructions to cover the event where the emergency bus fast transfer occurs and RBSVS actuates. i ADDITIONAL _lHEQEMAIl0B
- a. Manufacturer and_model_ number __of_ failed _ comp _onent_Lal N/h
- b. LEB_ numbers _of_ previous _similar_eyents None i
1 I
I 1
l NRC F.rm 308A (649) -