Pages that link to "05000277/LER-2024-001, Automatic Reactor Scram Due to an Invalid Generator Lockout"

The following pages link to 05000277/LER-2024-001, Automatic Reactor Scram Due to an Invalid Generator Lockout:

Displayed 5 items.

• 10 CFR 50.73(a)(2)(iv)(A), System Actuation ‎ (← links)
• 05000277/LER-2024-001 (redirect page) ‎ (← links)
  • 05000277/LER-2014-002 ‎ (← links)
  • 05000277/LER-2006-004 ‎ (← links)
  • 05000277/LER-2001-005 ‎ (← links)
  • 05000277/LER-2001-004 ‎ (← links)
  • 05000277/LER-2001-003 ‎ (← links)
  • 05000277/LER-2001-002 ‎ (← links)
  • 05000277/LER-2001-001 ‎ (← links)
  • 05000277/LER-1982-010, Sanitized Version of LER 82-010/01X-0:on 820413,Eberline Instrument Corp Reported 9.175 Rem Exposure to TLD Badge. Caused by Deliberate Tampering W/Badge Found Near Radiation Source.Individual Denied Access to Site ‎ (← links)
  • 05000277/LER-1982-027, Forwards LER 82-027/01T-0.Detailed Event Analysis Encl ‎ (← links)
  • 05000277/LER-1993-013, Forwards LER 93-013-00.LER Originally Distributed to All Individuals & Organizations Except DCD Due to Administrative Oversight ‎ (← links)
  • 05000277/LER-1982-021, Forwards LER 82-021/03L-0.Detailed Event Analysis Encl ‎ (← links)
  • 05000277/LER-1982-041, Forwards LER 82-041/01T-0.Detailed Event Analysis Submitted ‎ (← links)
  • 05000277/LER-1981-002, Forwards LER 81-002/01T-0 ‎ (← links)
  • 05000277/LER-1976-011, Telecopy LER 76-011/01P:on 760219,allowable Gross Activity Gaseous Release Rate Exceeded Tech Spec.Caused by Xenon Gases Released During Filter Demineralizer Backwash.No Immediate Corrective Action Possible ‎ (← links)
  • 05000277/LER-1976-012, Telecopy LER 76-012/01P:on 760225,allowable Gross Activity Gaseous Release Rate Exceeded Tech Spec.Caused by Xenon Gases Released During Filter Demineralizer Backwash.No Immediate Corrective Action Possible ‎ (← links)
  • 05000277/LER-1976-015, Telecopy LER 76-015/01P:allowable Gross Activity Gaseous Release Rate Exceeded Tech Spec.Caused by Xenon Gases Released During Filter Demineralizer Backwash.No Immediate Corrective Action Possible ‎ (← links)
  • 05000277/LER-1983-006, Forwards LER 83-006/01T-0.Detailed Event Analysis Submitted ‎ (← links)
  • 05000277/LER-1979-002, Forwards LER 79-002/01T-0 ‎ (← links)
  • 05000277/LER-1982-030, Telecopy Message of LER 82-030/01P:on 820917,contaminated Water Released from Recombiner Bldg Into Storm Drain Sys. Caused by Spurious Actuation of Fire Protection Sprinkler Sys in B Filter Train of Exhaust Ventilation Sys ‎ (← links)
  • 05000277/LER-1981-013, Forwards LER 81-013/01T-0.Provides Narrative Description of 810203 Occurrence Re Failure of Valves to Meet Seismic Qualification Requirements ‎ (← links)
  • 05000277/LER-1997-003, Forwards LER 97-003-00,concerning Inoperability of Hpcis When Wire Lug Was Lifted in Control Circuit on 970601 ‎ (← links)
  • 05000277/LER-1981-028, Forwards LER 81-028/01T-0.Detailed Event Analysis Also Submitted ‎ (← links)
  • 05000277/LER-1998-005, Forwards LER 98-005-00 Re 980824 Failure to Meet TS Actions for Suppression chamber-to-drywell Vacuum Breaker Not Being Fully Seated ‎ (← links)
  • 05000277/LER-1997-007, Forwards LER 97-007-00 Which Documents Event That Occurred at Peach Bottom Atomic Power Station,Units 2 & 3 on 740705 ‎ (← links)
  • 05000277/LER-1997-008, Forwards LER 97-008-00,reporting Discovery of safety-related Logic Components That Were Not Tested Per TS Surveillance Requirements on 740705 ‎ (← links)
  • 05000277/LER-1982-035, Forwards Revised LER 82-035/01X-1.Revised Detailed Event Analysis Encl ‎ (← links)
  • 05000277/LER-1998-003, Forwards LER 98-003-00,which Reports 980513 Failure to Meet TS for Main Crev,Per 10CFR50.73(a)(2)(i)(B) ‎ (← links)
  • 05000277/LER-1998-002, Forwards Details of LER 98-002-00 Re 980505 Loss of Both Trains of Main CR Emergency Ventilation Sys,Per Requirements of 10CFR50.73(a)(2)(i)(B) ‎ (← links)
  • 05000277/LER-1989-007, Corrected LER 89-007-00:on 890411,green Discoloration Discovered in Grease on Stabs of Control Fuses in Switchgear.Root Cause of Event Under Investigation.Stabs Lubricated W/Different Type of Approved Grease ‎ (← links)
  • 05000277/LER-1989-006, Corrected LER 89-006-00:on 890209 & 25,determined That Tubing to Containment Isolation Valve Installed W/Inadequate Support & Containment Atmosphere Control & Dilution Sys Not Per Applicable Installation Criteria.Controls Estab ‎ (← links)
  • 05000277/LER-1998-004, Forwards LER 98-004-00,reporting Failure to Meet TS Surveillance Requirements for One off-site Source Being Inoperable & 10CFR50.73(a)(2)(i)(B) ‎ (← links)
  • 05000277/LER-1997-006, Forwards LER-97-006-00,concerning Unplanned ESF Actuation During 4-kV Electrical Bus Relay Testing Activities on 970923 ‎ (← links)
  • 05000277/LER-1997-004, Forwards LER 97-004-00 Re non-compliance of MCR Emergency Ventilation Sys TS Which Occurred on 970710 ‎ (← links)
  • 05000277/LER-1998-001, Forwards LER 98-001-00,re Failure to Perform SR for RCS Temp Limits When Starting First Recirculation Pump ‎ (← links)
  • ENS 56936 ‎ (← links)
  • IR 05000277/2024002 ‎ (← links)
  • ML24227A549 ‎ (← links)
  • ML24081A120 (redirect page) ‎ (← links)
    • ML24081A118 ‎ (← links)
  • 05000277/LER-2024-001, Submittal of LER 2024-001-00 for Peach Bottom Atomic Power Station (PBAPS) Unit 2, Automatic Reactor Scram Due to an Invalid Generator Lockout (redirect page) ‎ (← links)
  • 05000277/LER-2024-003, Automatic Reactor Scram Following Main Turbine Trip Due to Degraded Condenser Vacuum ‎ (← links)
  • 05000277/LER-2024-002, Uncoordinated DC Circuits Cause Unanalyzed Condition ‎ (← links)
  • 05000277/LER-2024-001, Automatic Reactor Scram Due to an Invalid Generator Lockout ‎ (← links)
  • 05000277/LER-2022-002, Automatic Depressurization System Safety Relief Valve Actuator Diaphragm Degraded ‎ (← links)
  • 05000277/LER-2022-001, Automatic Reactor Scram Due to Loss of Power to Both RPS Buses ‎ (← links)
  • 05000277/LER-2021-003, Manual Reactor Scram Due to Degrading Condenser Vacuum ‎ (← links)
  • 05000277/LER-2021-001, High Pressure Coolant Injection System Declared Inoperable Due to Instrument Power Inverter Failure ‎ (← links)
  • 05000277/LER-2020-002, Degraded Condition Due to RPV Instrument Nozzle Leakage ‎ (← links)
  • 05000277/LER-1998-003-01, :on 980513,failure to Meet TS for Main Control Room Emergency Ventilation,Was Identified.Caused by Failure to Follow GP-25 Procedure Guidance.Main Control Room Emergency Ventilation Relays Inspected for Loose Screws ‎ (← links)
  • 05000277/LER-1997-010, :on 971229,failure of 2A Reactor Feedpump Turbine to Trip,Occurred.Caused by Main Control Room pushbutton.2A RFPT Trip Device Repaired,Reinstalled & Tested to Prove Operability ‎ (← links)
  • 05000277/LER-1997-010-01, Forwards LER 97-010-01,reporting 971229 Failure of 2A Reactor Feedpump Turbine to Trip in Timely Manner ‎ (← links)
  • 05000277/LER-1997-009, :on 971109,reactor Scram Occurred.Caused by Generator Lockout Condition & Subsequent Turbine Trip Failure of 2A Reactor Feedpump Turbine to Trip on Demand During Recovery Activities.Reset Appropriate Scram Logics ‎ (← links)
  • 05000277/LER-1997-009-01, Forwards LER 97-009-01,reporting Reactor Scram on 971109, Resulting from Generator Lockout Condition & Subsequent Turbine Trip.Rev to Original Submittal & Discussion Anomalies Found w/2A Reactor Feedpump Turbine Trip Sys ‎ (← links)
  • 05000277/LER-1988-012-01, :on 880524,discovered That Units 2 & 3 Drywell High Range Radiation Monitors out-of-svc W/O Being Reported to NRC as Required.Caused by Personnel Errors.Monitors Returned to Svc on 880830.Training Conducted ‎ (← links)
  • 05000277/LER-1989-019-01, :on 890830,discovered That Five Doors Requiring Monthly Functional Tests,Per Tech Specs,Not Included on Surveillance Test.Caused by Deficiency in Methodology & Refs Used During Surveillance ‎ (← links)
  • 05000277/LER-1989-011, :on 890424,scram Discharge Vol Drain & Vent Valve Stroking Surveillance Test Not Performed.Caused by Procedural Deficiency & Scheduling Error.Surveillance Test Completed Satisfactorily on 890429 ‎ (← links)
  • 05000277/LER-1989-018-01, :on 890818,personnel Failed to Place APRM Rod Block Settings in Tripped Condition within 1 H of Determining Nonconservative Settings.Total Core Flow Calibr & APRM Sys Calibr Revised Re Personnel Actions ‎ (← links)
  • 05000277/LER-1988-027, :on 881026,determined That Surveillance Logs Did Not Contain Required Max Fraction of Limiting Power Density to Be Compared W/Fraction of Rated Power Daily. Caused by Inadequate Controls.Program Upgraded ‎ (← links)
  • 05000277/LER-1987-008, :on 870529,control Room Ventilation Radiation Monitoring Sys Found Inoperable.Caused by Piping Error Made During Initial Installation.Piping Errors Corrected & Sys Returned to Svc ‎ (← links)
  • 05000277/LER-1988-032-01, :on 881212,determined That Control Room Temp Could Exceed Design Basis During Emergency Operation.Noted During Exam of Concerns Stated in NRC Info Notice 88-061. Caused by Lack of Procedure.Procedure Revised ‎ (← links)
  • 05000277/LER-1989-013-01, :on 890603,required Test for Diesel Generator Cardox Room Smoke Detectors Was Not Performed.Caused by Lack of Effective Method for Communicating Surveillance Test Status to Shift Manager ‎ (← links)
  • 05000277/LER-1989-017-01, :on 890815,failure to Establish Continuous Fire Watch Occurred Due to Inoperable Sprinkler Sys.Caused by Ineffective Fire Protection Sys Training.Event Reviewed W/Personnel ‎ (← links)
  • 05000277/LER-1989-014-01, :on 890517,noted That Required Surveillance Test for Radwaste Bldg 116 Ft Elevation Chemical Addition & Laundry Room Smoke Detectors Overdue. Caused by Procedural Deficiency ‎ (← links)
  • 05000277/LER-1989-008-01, :on 890415,incorrect Undervoltage Trip Fuses Placement by Operator Occurred Due to Inadequacy of Training Resulting in Isolation of RWCU Sys.Caused by Administrative Deficiency.Training Ltr Will Be Issued ‎ (← links)
  • 05000277/LER-1989-005-01, :on 890406,determined That Numerous Pull Apart Terminal Blocks Found Not to Be Securely Fastened Causing Failure of Safety Function.Caused by Deficiency Inadequacy. Pull Apart Terminal Blocks Refastened ‎ (← links)
  • 05000277/LER-1988-027-01, :on 881026,review of Results of Surveillance Tests Determined That Tests Did Not Require Max Fraction of Limiting Power Density to Be Compared to Fraction of Rated Power Daily.Caused by Procedural Inadequacy ‎ (← links)
  • 05000277/LER-1989-006-01, :on 890209,NRC Inspector Discovered That Tubing to Torus Air & Nitrogen Purge 18 Inch Containment Isolation Valve Installed W/Inadequate Support.Caused by Deficient Installation & Maint Instructions ‎ (← links)
  • 05000277/LER-1989-007-01, :on 890401,green Discoloration Discovered in Grease on Stabs of Several Control Fuses in 4 Kv Switchgear. Cause Under Investigation.Switchgear Fuse Boxes Inspected & Cleaned as Necessary ‎ (← links)
  • 05000277/LER-1989-015-01, :on 890721,main Turbine Bypass & Control Valves Opened,Causing Main Steam Line Pressure to Decrease to Approx 480 Psig & Full Reactor Scram.Caused by Malfunction of Pressure Regulator Set.Component Replaced ‎ (← links)
  • 05000277/LER-1989-016-01, :on 890722,APRM hi-hi Signal Caused LPRM Detector 4B-40-33 to Spike Upscale.Caused by Output Signal of LPRM Detector Spiking High.Detector Placed in Bypass Position & Scram Signal Reset ‎ (← links)
  • 05000277/LER-1989-012, :on 890519,reactor Hi Lo Level Alarm Sounded & Reactor Feed Pumps B & C Tripped Simultaneously.Caused by Failure of Feedwater Level Control Switch.Switch Replaced, Amplifier Replaced & Procedures Revised ‎ (← links)
  • 05000277/LER-1988-012, :on 880524,discovered That Drywell high-range Radiation Monitors out-of-svc W/O Being Reported to Nrc. Caused by Combination of Personnel Errors.Monitors Returned to Svc & Manual Developed ‎ (← links)
  • 05000277/LER-1989-003, :on 890207,Group 2C Primary Containment Isolation Sys Valve Isolation Occurred & Reactor Scrammed. Caused by Inadvertent Reactor Vessel Pressure Signals. Scram Reset & Isolation Valve Replaced ‎ (← links)
  • 05000277/LER-1989-004-01, :on 890320,HPCI Sys Unable to Fulfill Safety Function During Postulated Design Basis Events.Caused by Design Deficiency.On 890330,step Starting Resistors Removed from Power Circuits ‎ (← links)
  • 05000277/LER-1989-012-01, :on 890519,feedwater Control Malfunction Occurred Resulting in Low Level Reactor Scram.Caused by Failure of Feedwater Level Control Selector Switch.Failed Switch Replaced & Procedures Enhanced ‎ (← links)
  • 05000277/LER-1988-029, :on 881110,inadequate Sealing of ECCS Pump Rooms Results in Plant Being Out of Design Basis.Caused by Lack of Clear Assignment of Penetrations to Mechanical or Civil Disciplines of Engineer Organization ‎ (← links)
  • 05000277/LER-1989-010-01, :on 890514,50% Control Rod Density Exceeded W/O Demonstrating Operability of Rod Sequence Control Sys.Caused by Personnel Error.Shift Manager Counseled & Control Rod Pull Sheet Revised ‎ (← links)
  • 05000277/LER-1989-009-01, :on 890505,while Performing HPCI Operability Testing,Hpci Sys Did Not Respond Properly to Flow Control Signals.Caused by Failure to Follow Installation Instructions.Mod Process Enhancements Planned ‎ (← links)
  • 05000277/LER-1985-005, :on 850612,intermediate Range Monitors F & B Discovered Inoperable W/Reactor Protection Sys Channel B Logic Out of Tripped Condition,Violating Tech Specs.Caused by Procedural Deficiency.Procedure Revised ‎ (← links)
  • 05000277/LER-1987-014-01, :on 870728,containment Isolations Occurred When E-22 4 Kv Emergency Bus Supply Breaker Tripped Open.Cause Undetermined.No Corrective Actions Planned to Prevent Recurrence ‎ (← links)
  • 05000277/LER-1987-011-01, :on 870710,primary Containment Isolation Sys Group Iib Isolation Occurred While Operating RHR Sys in Shutdown Cooling Mode.Caused by Blown Fuse.Fuse Replaced ‎ (← links)
  • 05000277/LER-1987-012-01, :on 870710,lightning Strike on 220 Kv Line Caused Unit 3 Startup Feed Breaker to Trip Resulting in Primary Containment Isolation Actuations for Several Unit 2 & 3 Sys.All Isolations Reset ‎ (← links)
  • 05000277/LER-1998-002-01, Forwards LER 98-002-01 Which Retracts Original LER Re Loss of Both Trains of MCR Emergency Ventilation That Occurred on 980505 ‎ (← links)
  • 05000277/LER-1987-024-01, :on 871112,isolation of RWCU Sys Occurred. Caused by Blowing of Fuse (12A-F-1) Which Supplies Power to Four Temp Switches.Fuse 12A-F1 Replaced & Isolation RWCU Sys Reset. W/8 Ltr ‎ (← links)
  • 05000277/LER-1998-004-01, :on 980606,failure to Meet TS for off-site Source,Was Determined.Caused by Lightning Strike & No Positive Verification That Tap Changer Was operational.3SU Tap Changer Circuitry Was Repaired,Tested & Returned to Svc ‎ (← links)
  • 05000277/LER-1987-023-01, :on 871014,HPCI Sys Disabled Due to Blown Logic Fuse.Cause Unknown.Fuse Replaced within 5 Minutes.No Addl Corrective Actions Planned ‎ (← links)
  • 05000277/LER-1987-007, :on 870619,full Scram Signal Generated by Reactor Protection Sys Logic.Caused by Procedural Deficiency & Personnel Error.Rev of Intermediate Range Monitors Postponed Due to Administrative Problems ‎ (← links)
  • 05000277/LER-1987-010-01, :on 870630,outboard Containment Isolation Valves Received Isolation Signals While RWCU Sys Isolation Control Relay Being Replaced.Caused by Inadequate Blocking Method.Involved Operators Counseled ‎ (← links)
  • 05000277/LER-1987-022-01, :on 870929,loss of HPCI Occurred Due to Blown Logic Fuse.Probably Caused by Underrating of Socket for Undervoltage Relay on Battery 2D Charger.Hpci Logic Fuse Replaced & Static Inverter Placed on Ac Feed ‎ (← links)
  • 05000277/LER-1987-017-01, :on 870916,partial Ventilation Isolation Occurred During Temporary Clearing of Blocked Sys Logic. Caused by Inadequate Review of Blocking Permits.Permit Will Be Revised by 871030 ‎ (← links)
  • 05000277/LER-1987-021-01, :on 870916,primary Containment Isolation Sys Actuated.Caused by Power Interruption to Distribution Panel. Isolation Reset & Indications Restored ‎ (← links)
  • 05000277/LER-1989-003-01, :on 890207,group 2C Primary Containment Isolation Sys Valve Isolation Occurred Resulting in motor- Operated Feedwater Flush Valves Receiving Signals to Close. Caused by Stated Inadvertent Signals ‎ (← links)
  • 05000277/LER-1989-002-01, :on 890202,determined That Several Conditions Found During Analysis of Unsuccessful Special Test of Emergency Cooling Sys May Inhibit Function of Sys Needed to Maintain Safe Shutdown ‎ (← links)
  • 05000277/LER-1987-007-01, :on 870619,full Scram Signal Generated by Reactor Protection Sys Logic.Caused by Procedural Deficiencies,Combined W/Personnel Error.Procedural Revs Being Made ‎ (← links)
  • 05000277/LER-1987-020-01, :on 870904,HPCI Sys Determined Inoperable Due to Opening of Resistor in Voltage Dropping Assembly.Exact Cause for Opening of Resistor Unknown.Resistor Replaced on 870914 ‎ (← links)
  • 05000277/LER-1987-019-01, :on 870904,shutdowm Cooling Isolation & RHR Pump Trip Occurred Whem RHR a Logic Temporarily de- Energized.Caused by Loose Connection at Fuse Terminal.Lead at Fuse Tightened & Isolation Signal Reset ‎ (← links)
  • 05000277/LER-1989-001-01, :on 890120,discovered That Instrument Calibr Requirements Associated w/intermediate-range Monitor Input Into Rod Block Instrumentation Not Satisfied by Existing Procedures.Caused by Personnel Inadequacies ‎ (← links)
  • 05000277/LER-1987-018-01, :on 870828,shutdown Cooling Isolation Occurred & RHR Pump Tripped.Caused by Deenergization of RHR a When Safety Block Reapplied.Review of Nuclear Plant Blocking Underway to Identify Specific Improvements ‎ (← links)
  • 05000277/LER-1987-009-01, :on 870602,primary Containment Isolation Sys Group III Outboard Valve Isolation & Half Scram of Reactor Sys Occurred.Caused by Loss of Power to Reactor Protection Sys.Breaker 23 Reset & Breaker 52-3691 Closed ‎ (← links)
  • 05000277/LER-1987-016-01, :on 870820,containment Isolations Occurred Due to Startup Source Trip.Caused by Inadequate Concern for Potential Electrical Hazard by Maint Craft Supervision. Supervisors Involved Counseled ‎ (← links)
  • 05000277/LER-1987-013-01, :on 870820,primary Containment Isolation Sys Group Iib Isolation Occurred Causing Loss of Power to RHR Sys a Logic Bus.Caused by Blown Fuse.Logic Cleared.Fuse Replaced & Isolation Signal Reset ‎ (← links)
  • 05000277/LER-1987-008-01, :on 870529,incorrect Piping Configurations Discovered in Control Room Ventilation Radiation Monitoring Sys.Cause Unknown.Sample Lines Realigned in Correct Configuration & Sys Returned to Svc ‎ (← links)
  • 05000277/LER-1987-015-01, :on 870816,primary Containment Isolation Sys Group II Inboard & Outboard Isolation Occurred.Caused by Inadequate Tree Trimming in Transmission Corridor.Startup Source Restored & Tree Removed ‎ (← links)
  • 05000277/LER-1987-022, :on 870929,HPCI Disabled Due to Blown Power Fuse in HPCI Logic Panel.Cause Unknown.Fuse Replaced within 35 Minutes,Static Inverter Placed on Ac Feed & Battery Terminal Voltage Monitored Every 4 H ‎ (← links)
  • 05000277/LER-1997-006-02, :on 970923,DG Auto Start During 4-kV Relay Testing Occurred.Caused by Personnel Error.Need for Exercising Caution When Removing or Installing Relay Cover Was Discussed W/I&C Technicians ‎ (← links)
  • 05000277/LER-1997-004-02, :on 970710,discovered non-compliance W/Ts When TS Action Times Were Exceeded.Caused by Procedural Control Not Being Adequate to Ensure Radiation Monitor Would Be Maintained in Trip Condition.Made Rev to GP-25 App 13 & 14 ‎ (← links)
  • 05000277/LER-1998-001-02, :on 960118,failure to Perform SR for First Recirculation Pump Start Was Noted.Caused by Inadequate Review of ITS Requirements.Revised Procedure to Include Appropriate SRs ‎ (← links)
  • 05000277/LER-1987-004, :on 870407,primary Containment Isolation Occurred Due to Partial Loss of Startup Source.Operators Immediately Switched Load to 2 Startup Source ‎ (← links)
  • 05000277/LER-1997-005-02, :on 970808,discovered TS non-compliance Associated W/Rod Block Contact Testing.Caused by Rev in Oct 1989,attempted to Consolidate Testing of Rod Block Logic from Two Instrument Panels.Procedure Revised ‎ (← links)
  • 05000277/LER-1987-004-02, :on 870407,primary Containment Isolations Occurred.Caused by Partial Loss of Offsite Power Due to Buildup of Snow on Power Lines & Contact W/Trees.Trees Near 220-kV Lines Trimmed ‎ (← links)
  • 05000277/LER-1986-018-02, :on 860826,reactor Water Level Transmitter Found Out of Svc.Caused by Personnel Failure to Return Instrument Rack Isolation Valves to Proper post-test Position.Transmitter Valved Into Svc ‎ (← links)
  • 05000277/LER-1987-006-01, :on 870423,Group III Outboard Isolation Occurred,Standby Gas Treatment Sys B Fan Started & Half Scram Signal Generated.Cause Not Determined.Reactor Protection Sys Motor Generator Returned to Svc ‎ (← links)
  • 05000277/LER-1987-005-02, :on 870407,main Steam Line Drain Isolation Valves Had Unsatisfactory Test Results.On 870404,valve Opened When Test Attempted & on 870405,discovered That Motor Control Circuitry Rewired Improperly ‎ (← links)
  • 05000277/LER-1986-002-01, :on 851224,continuous Fire Watch in M-G Set Lube Oil Room Not Established When Smoke Detectors Bypassed on 851223 Due to Spurious Signals.Continuous Watch Established on 860107 ‎ (← links)
  • 05000277/LER-1986-022-01, :on 861013,low Condenser Vacuum Scram Occurred. Caused by Loose Startup Screen Matl Stuck in Valve Seat. Screen Matl Removed.Condensate Pump Suction Lines for Units 2 & 3 Will Be Inspected for Screen Matl ‎ (← links)
  • 05000277/LER-1986-023-01, :on 861011,improper Indication Observed on Primary Containment Valves Position Display Panel.Caused by Mechanical Interference or Binding in Ball Valve.Valve Replaced ‎ (← links)
  • 05000277/LER-1986-008-01, :on 860227,Group II & III Outboard Isolation Occurred & half-scram Signal Generated While Unit at 100% Power.Caused by Erratic Voltage Control Associated W/Use of Rheostat for Adjustment ‎ (← links)
  • 05000277/LER-1986-020-01, :on 860817,failure to Maintain Cold Shutdown Conditions & Exceeding Torus Vol Limit Discovered.Caused by Poor Planning of Proposed Operation by Station Supervision. GP-12 Revised ‎ (← links)
  • 05000277/LER-1986-016, :on 860709,HPCI Sys Declared Inoperable Due to Turbine Control Valve Not Opening Beyond 75%.Caused by Ground in electro-hydraulic Controls.Control Box Replaced. Failed Box Returned to Mfg for Repairs ‎ (← links)
  • 05000277/LER-1986-021-01, :on 860813,discovered That Insp & Wire Replacements Performed on Core Spray Sys Min Flow Valve Operators W/O Authorization & Safety Blocking.Caused by Supervisor Error.Supervisor Counseled ‎ (← links)
  • 05000277/LER-1999-005-01, :on 990616,failure to Maintain Provisions of FP Program Occurred.Caused by Less than Adequate Engineering Rigor in Both Development & Review Analysis.Fire Watch Immediately Established.With ‎ (← links)
  • 05000277/LER-1987-003-01, :on 870328,isolation of RHR Shutdown Cooling Suction Valves & Head Spray Injection Valves Occurred. Caused by Fuse Removed from RHR Control Circuitry During Safety Block.Personnel Counseled ‎ (← links)
  • 05000277/LER-1986-019-01, :on 860808,combined Containment Leak Rate of Penetrations & Valves Subj to Type B & C Tests Determined in Excess of Allowable Limit.Caused by Normal Valve Degradation.Valves Repaired & Retested ‎ (← links)
  • 05000277/LER-1986-007, :on 860203,Group III Outboard Isolation Occurred & half-scram Signal Generated While Unit 2 Shut Down.Caused by Erratic Voltage Control from Rheostat Usage. Surveillance Test Procedure Revised ‎ (← links)
  • 05000277/LER-1986-008, :on 860227,Group III Outboard Isolation Occurred & half-scram Signal Generated.Caused by Reactor Protection Sys B M-G Set Output Voltage Found Lower than Desired.Maint Request Form Issued ‎ (← links)
  • 05000277/LER-1986-006, :on 860201,primary Containment Isolation Sys Group III Outboard Isolation Occurred & Reactor Protection Sys Generated half-scram Signal.Caused by Starting Large Pump Motor While motor-generator Out of Svc ‎ (← links)
  • 05000277/LER-1986-025-01, :on 861210 & 16,dedicated Fire Watches Not Established in Emergency Diesel Generator Rooms.Caused by Failure to Adhere to Procedures.Event Reviewed W/Operations Personnel.Surveillance Test ST 8.1 Revised ‎ (← links)
  • 05000277/LER-1988-021-01, :on 880913,primary Containment Isolation Sys (PCIS) Group II Isolation Occurred as Result of Momentary Loss of Power to PCIS Logic.Caused by Opening of 2 Circuit Breakers by Util non-licensed Const Personnel ‎ (← links)
  • 05000277/LER-1986-024-03, :on 861209,blown Control Fuse Resulted in Closure of Oxygen Analyzer Outboard Sample Valves.Caused by Improper Use of Test Equipment.Fuse Replaced,Isolation Reset & Sample Valves Returned to Svc ‎ (← links)
  • 05000277/LER-1986-015-01, :on 860620,w/unit in Cold Shutdown,Total Combined Leakage of Penetrations & Valves Subj to Type B & C Tests Exceeded Allowable Leak Rate Limit.Caused by Normal Valve Degradation.Valve Packing Replaced ‎ (← links)
  • 05000277/LER-1988-017-01, :on 880705,shutdown Cooling Resulted from Spurious High Pressure Signal.Caused by Lack of Contractor Engineer Supervision & Training.Ltr Requiring Proper Guidance to Support Personnel Will Be Issued ‎ (← links)
  • 05000277/LER-1988-015-01, :on 880628,continuous Firewatch in Cable Spreading Room Left Post Unattended for Approx 20 Minutes in Violation of Tech Spec 3.14.B.4.a.Caused by Personnel Error. Firewatch Reestablished ‎ (← links)
  • 05000277/LER-1987-001-01, :on 870311,suppression Pool Water Vol Exceeded Max Tech Spec Limit.Caused by Leaking Check Valve in RHR Loop A.Suppression Pool Water Vol Restored within Tech Spec Limits ‎ (← links)
  • 05000277/LER-1999-003, :on 990318,failure to Maintain Provisions of Fire Protection Program Was Noted.Caused by Previous Analysis Which Contained Erroneous Info Re Effects of Sump Room Flooding.Temporary Plant Alterations Were Installed ‎ (← links)
  • 05000277/LER-1986-017-01, :on 860704,both Channels of Rod Block Monitor Bypassed.Caused by Failed Relay Associated W/Control Rod 58-43.Defective Relay Replaced to Return Rod Block Monitor to Svc ‎ (← links)
  • 05000277/LER-1986-016-01, :on 860709,HPCI Sys Declared Inoperable Due to Turbine Control Valve Not Opening Beyond 75%.Caused by Ground in EG-M Control Box.Box Replaced & Sys Returned to Svc ‎ (← links)
  • 05000277/LER-1986-011-01, :on 860326,inboard Suction Valve of RWCU Sys Received Unexpected Isolation Signal.Caused by Technicians Testing Wrong Indicating Switch During Surveillance Testing. Instrument Technicians Counseled ‎ (← links)
  • 05000277/LER-1986-014-02, :on 860618,shutdown Initiated Due to Potential Loss of Emergency Svc Water (Esw).Caused by Need to Repair ESW Pipe Leak Occurring in Inlet to RHR Room Cooler 2A.Pipe Temporarily Repaired & Ultrasonically Tested ‎ (← links)
  • 05000277/LER-1997-009-02, :on 971109,generator Lockout & Subsequent Turbine Trip Occurred.Caused by Turbine Trip Resulting from Generator Lockout Signal.Appropriate PCIS & RPS Scram Logics Were Reset ‎ (← links)
  • 05000277/LER-1985-019, :on 850919,RHR Pump Declared Inoperable.Caused by Low Flow in Low Head Region of Pump Performance Curve. Pump Removed from Svc & Inspected.Pump Determined to Be in Compliance W/Tech Spec Requirements ‎ (← links)
  • 05000277/LER-1997-008-02, :on 740705,logic Sys Functional Testing Did Not Contain All Required Testing Per TS Surveillance Requirements.Caused by Test Procedures Not Containing Required Testing.Untested Contacts Tested & Proved Operable ‎ (← links)
  • 05000277/LER-1997-007-02, :on 970821,engineering Personnel Identified Potential Suppression Chamber Steam Bypass Leakage Path Between Air Spaces of Drywell & Torus.Caused by Original Design Deficiency.Drywell Purge Supply Valve Disabled ‎ (← links)
  • 05000277/LER-1997-010-02, :on 971229,2A RFPT Failed to Trip When RO Pushed CR 2A RFPT Trip push-button.Caused by Intermittent Failure Mechanism.Repaired,Reinstalled & Tested Operability of 2A RFPT ‎ (← links)
  • 05000277/LER-1985-024, :on 851103,blocking Removed from Drywell Oxygen Analyzer Lines a & C Before Valves Repaired & Tested.Caused by Operator Failure to Ensure Inoperable Isolation Valve Properly Tested.Blocking Restored ‎ (← links)
  • 05000277/LER-1998-008-01, :on 981130,circuit Breaker SU-25 Tripped.Caused by Less than Adequate Procedural Guidance.Operators Verified Sys Integrity & Successfully Returned Sys to Svc.With ‎ (← links)
  • 05000277/LER-1985-026, :on 851226,fully Withdrawn Control Rod 22-11 Blocked to Accommodate Repair of Leak on Hydraulic Control Unit Accumulator.Caused by Personnel Error.Crd Blocking Sequences Revised ‎ (← links)
  • 05000277/LER-1986-013-01, :on 860423,main Turbine Control Valve Fast Closure Scram Occurred During Routine Test.Caused by Trapped Air in Turbine Hydraulic Control Line.Fast Acting Solenoid Valves Replaced ‎ (← links)
  • 05000277/LER-1986-010-02, :on 860413,containment Isolations Occurred When Startup Source 3 Deenergized.Caused by Transformer 1 Failure,Rupture & Subsequent Fire.Fire Extinguished.Startup Source Restored.Transformer Repaired ‎ (← links)
  • 05000277/LER-1998-007-02, :on 981107,failure to Meet TS & Associated LCO Requirments of Absolute Difference in APRM & Calculated Power of Less than 2% Was Noted.Caused by Substitute Valves Being Used.Removed Substitute Valves.With ‎ (← links)
  • 05000277/LER-1986-012-01, :on 860413,partial Group I & II Isolations Occurred Due to Loss of Power to E-22 & E-23 4 Kv Emergency Busses.Caused by Failed Speed Switch Device on E-2 Diesel. Switch Replaced ‎ (← links)
  • 05000277/LER-1988-008, :on 880328,failure to Submit Special Rept Re Inoperability of Cardox Sys in Control Room on Time Determined.Caused by Lack of Programmatic Controls.Limiting Condition for Operation Instructions Revised ‎ (← links)
  • 05000277/LER-1987-032-01, :on 871110,failure to Comply W/Cable Routing & Separation Criteria Identified.Caused by Engineering Design Personnel Failure to Provide Adequate Design to Const Personnel.All Mod Cables Wrapped ‎ (← links)
  • 05000277/LER-1988-005, :on 880303,as-built Anchorage Configurations of Unit 2 & 3 Main Control Room Panel Did Not Conform W/ Original Installation Requirements.Caused by Original Installation Error.Base Channels Welded ‎ (← links)
  • 05000277/LER-1999-004, :on 990521,multiple Unplanned Esfas Occurred During Planned Electrical Bus Restoration Following Maint Activities.Caused by Inadequate Configuration Control.Power Was Restored to 3E Transformer Per Plant Procedures ‎ (← links)
  • 05000277/LER-1987-031-01, :on 871231,recognized That Extraction Steam Block Valves Have Common Electrical Feed & Will Fail Closed on Loss of Power.Caused by Error During Design Process. Plant Mod Will Be Implemented, ‎ (← links)
  • 05000277/LER-1988-025, :on 881027,Group II Primary Containment Isolation Sys Actuation Resulted from Personnel Error Re Tripping of Breaker.Caused by Inadvertently Grounding B Phase of Three Phase Circuit Breaker ‎ (← links)
  • 05000277/LER-1988-026-01, :on 881029,primary Containment Isolation Resulted from Undervoltage Trip of Reactor Protection Sys Channel a Due to Sensitive Rheostat.Caused by Craftsman Inadvertently Bumping Voltage Control Rheostat ‎ (← links)
  • 05000277/LER-1987-027-01, :on 870430,primary Containment Isolation Occurred.Caused by Personnel Error by Inducing Ground & Blowing Fuse While Applying Blocking Permit.Fuse Replaced & Leads Restored to Original Condition ‎ (← links)
  • 05000277/LER-1988-023-01, :on 880926,determined That Nonconformance in Seismic Gap Between Unit 2 Reactor Bldg & Radwaste Bldg Placed Plant Outside of Design Basis.Caused by Drawing Error.Excess Concrete Removed ‎ (← links)
  • 05000277/LER-1988-022-01, :on 880919,concluded That Adequate Cell Switch Linkage Engagement Not Verified in Past & Possibility Exists That During Seismic Event,Addl Breakers May Have Failed. Caused by Inadequate Design of Control Linkage ‎ (← links)
  • 05000277/LER-1988-011-01, :on 880512,reactor Protection Sys Unexpectedly Generated Full Scram Signal.Caused by Test Engineer Inadvertently Grounding Circuit,Thereby Blowing Fuse.Scram Discharge Vol Drained & Scram Reset ‎ (← links)
  • 05000277/LER-1988-010-01, :on 880506,primary Containment Isolation Sys Group II Isolation Signal Actuated.Caused by Fuse Being Pulled W/O Adequate Review of Permit & Applications to Sys. Fuse Replaced.Procedure Revised ‎ (← links)
  • 05000277/LER-1988-017, :on 880705,shutdown Cooling Isolation Occurred as Result of Spurious High Pressure Signal.Caused by Lack of Supervision & Training Provided by Engineering Div Over Contractor Engineers.Isolation Reset ‎ (← links)
  • 05000277/LER-1988-001-06, :on 880428,blown Fuses Rendered One Independent Train of Several Engineering Safety Features Inoperable. Cause Unknown.Fuses Replaced & Physical Insp of Fuses Initiated to Determine Failure Mode ‎ (← links)
  • 05000277/LER-1998-006-02, :on 980915,automatic RWCU Isolation Occurred While Placing RWCU Sys in Svc.Caused by Unexpected Surge of Water.Procedure Change Was Initiated to Open MO-2-12-74 & RWCU Sys Was Successfully Returned to Svc.With ‎ (← links)
  • 05000277/LER-1988-018-01, :on 880727,determined That Surveillance Test ST-10.5, Rod Worth Minimizer (RWM) Operability Check, Did Not Verify Rod Block Function of Rwm.On 880819,determined That No Other Procedures Verified Function ‎ (← links)
  • 05000277/LER-1988-007-01, :on 871015,determined That Several Fire Barriers in Turbine & Radwaste Bldgs Had Gaps Filled W/ Unqualified Fill Matl & on 880415,discovered Hole in Floor of Cable Spreading Room ‎ (← links)
  • 05000277/LER-1998-005-02, :on 980824,noted Failure to Meet TS Actions for Suppression chamber-to-drywell Vacuum Breaker Not Being Fully Seated.Caused by Personnel Failing to Take All TS Required Actions.Temporary Procedure Changes Were Made ‎ (← links)
  • 05000277/LER-1988-019-01, :on 880729,primary Containment Isolation Sys Group II Actuation of Shutdown Cooling Occurred as Result of False High Reactor Pressure Signal.Caused by Procedural Deficiency.Isolation Reset ‎ (← links)
  • 05000277/LER-1986-003-01, :on 860124,full Reactor Scram Initiated Due to Failure of Diesel Generator E-2.Caused by Failure of Dc Solenoids for MSIVs AO-86B & AO-86D.Solenoids Replaced ‎ (← links)
  • 05000277/LER-1986-005-01, :on 860125,during Unit Shutdown,Shutdown Cooling & Head Spray Isolations Occurred While Fuse 16A-F16 in Panel 20C42 Repositioned.Caused by Deenergization of Relay Fed by Fuse.Shutdown Cooling Restored ‎ (← links)
  • 05000277/LER-1988-009-01, :on 880404,treated Liquid Radwaste Effluent Released W/O Prior Sampling.Caused by Personnel Error. Individual Counseled on Importance of Attention to Detail ‎ (← links)
  • 05000277/LER-1988-020-01, :on 880729,capacitors Which Connect 500 Kv Bus Tie to Phase a Potential Transformer Failed,Resulting in Fire in North Substation & Voltage Disturbance Resulting in ESF Actuations.Caused by Capacitor Failure ‎ (← links)
  • 05000277/LER-1987-030, :on 871230,partial Loss of Offsite Power Initiated Actuation of Primary Containment Isolation Sys. Caused by Failure of Time Delay Relay,Agastat Model 7022AD. Relay Replaced ‎ (← links)
  • 05000277/LER-1988-001-01, :on 880428,blown Fuses Rendered Independent Train of ESF Inoperable.Caused by Personnel Error.Fuses Replaced,Event Discussed W/Assistant Plant Operator & Operator Manual Written ‎ (← links)
  • 05000277/LER-1988-008-01, :on 880328,Tech Spec 3.14.B.4.b Violated Due to Util Failure to Submit Special Rept Re Inoperability of Control Room Cardox Sys within 31 Day Limit.Caused by Lack of Programmatic Controls ‎ (← links)
  • 05000277/LER-1986-001, :on 860101,reactor Protection Sys Initiated Full Reactor Scram.Caused by Incorrect Adjustment to Moisture Separator Drain Tank B Dump Valve Level Controller & Broken Air Supply Line to Tank Valve ‎ (← links)
  • 05000277/LER-1985-027-02, :on 851226,feedwater Flow Transient Occurred, Causing Low Reactor Water Level Scram & Group II & III Isolations.Caused by Reduction in Reactor Water Level When Reactor Feed Pump a Tripped.Damage Repaired ‎ (← links)
  • 05000277/LER-1987-028, :on 871217,design Deficiency That Could Permit Diesel Generator Trips During Seismic Event Discovered. Caused by Deficiency in Original Design.Two Possible Design Mods to Resolve Problem Being Evaluated ‎ (← links)
  • 05000277/LER-1987-031, :on 871231,loss of Power to Block Valves Could Result in Loss of Feedwater Heating Event Outside Design Basis of Plant.Caused by Error During Design Process.Plant Mod Prior to Startup of Each Unit Implemented ‎ (← links)
  • 05000277/LER-1988-016-01, :on 880701,degraded Voltage Protection Outside Design Basis of Plant Due to Design Deficiencies.Caused by Design Error.Plant Mod Performed to Change Time Delay Setting ‎ (← links)
  • 05000277/LER-1988-004, :on 880302,relay Trip Causing Breaker Trip Resulted in Containment Isolations & Inoperable Fire Pumps. Caused by Severe Heat Damage on Relay Coil.Coil Shipped to Mfg.Temporary Feed Installed ‎ (← links)
  • 05000277/LER-1988-014-01, :on 880614,primary Containment Ventilation Isolation Occurred.Caused by Personnel Error & Procedural Inadequacy.Isolation Reset After Standby Gas Treatment Sys Fan Secured ‎ (← links)
  • 05000277/LER-1988-005-01, :on 880303,control Panels Failed to Meet Original Seismic Qualifications.Caused by Installation Error & Not Following Design Drawings.Base Channel of Each Panel Welded to Floor Embed on Outside of Panel ‎ (← links)
  • 05000277/LER-1988-004-01, :on 880302,relay Tripped Causing Breaker Trip, Resulting in Containment Isolations & Inoperability of Fire Pumps.Caused by Unexpected Trip of Undervoltage Relay.Relay Coil Shipped to Mfg for Failure Analysis ‎ (← links)
  • 05000277/LER-1988-006-01, :on 880303,primary Containment Isolation Sys Group Iia Isolation Signal Occurred.Caused by Loss of Power to RHR Sys Logic Bus a Due to Pulled Fuse from Panel.Fuse Replaced & Isolation Reset ‎ (← links)
  • 05000277/LER-1988-003-01, :on 880302,ESF Actuation Occurred Due to Undervoltage Trip of Breakers While Adjusting Defective Voltage Rheostat.Caused by Defective Voltage Rheostat. Breakers Closed & Rheostat Replaced ‎ (← links)
  • 05000277/LER-1988-013-01, :on 880602,grace Period for Functional Testing of 14 of 25 Smoke Detectors in Cable Spreading Room Expired & Surveillance Test Not Completed.Caused by Personnel Safety Concern.Surveillance Test ST 15.86.2B Revised ‎ (← links)
  • 05000277/LER-1987-029, :on 871221,primary Containment Isolation Sys Group III Isolation Occurred.Caused by Personnel Error While Pulling Fuses to Apply Blocking Permit for Mod Work.Operator Counseled to Be Attentative to Duties ‎ (← links)
  • 05000277/LER-1987-028-01, :on 871217,design Deficiency Discovered Which Could Result in Diesel Generator Trips During Loss of Offsite Power Event.Caused by Deficiency in Original Design. Design Review of Cardox Sys Initiated ‎ (← links)
  • 05000277/LER-1981-004-01, /01P-0:on 810114,while Operating at 100% Power, During Routine Surveillance Test of Diesel Generator,Breaker E-32 Failed to Close on Request.Caused by Unidentified Mechanical Deficiencies.Breaker Replaced & Tested ‎ (← links)
  • 05000277/LER-1987-029-01, :on 871221,primary Containment Isolation Sys Group III Isolation Occurred.Caused by Personnel Error. Isolation Signal Reset within 5 Minutes & Reactor Bldg Ventilation Returned to Normal ‎ (← links)
  • 05000277/LER-1988-002-01, :on 880301,reactor Scrammed During Performance of Procedure GP-11.E, Reactor Protection Sys (RPS) - Scram Reset. Caused by Operator Error.Operator Counseled Re Importance of Attention to Detail ‎ (← links)
  • 05000277/LER-1979-054-03, /03L-0:on 791213,four Channel B Logic Steam Line Temp Monitors Were Indicating Low.Caused by Power Supply Inability to Provide Sufficient Output Voltage.Power Supply Replaced & Monitors Returned to Svc After Testing ‎ (← links)
  • 05000277/LER-1978-035-03, /03l-0 on 780830:E-3 Diesel Start Time to Reach Rated Voltage & Frequency Did Not Meet Surveillance Test Requirement,Probably Caused by Leaking Check Valve in the Hydraulic Sys Assoc W/The Air Booster Relay ‎ (← links)
  • 05000277/LER-1992-013-01, :on 920727,RWCU Sys Isolation Occurred & Recirculating Water Pump 2A Tripped.Caused by Failure to Follow Established RWCU Sys Operating Procedures.Bottom Head Drain Piping Will Be Cleaned During Outage ‎ (← links)
  • 05000277/LER-1997-003-03, :on 970601,HPCI Was Inoperable.Caused by Lifting of Common Power Wire Lug in HPCI Electrical Power Logic as Part of GP-25 Activity.Hpci Sys Was Restored to Operable Condition ‎ (← links)
  • 05000277/LER-1986-009-01, :on 860318,reactor Protection Sys Initiated Full Scram Signal While Reactor in Shutdown Mode at 0% Power.Caused by de-energization of Scram Discharge Vol High Water Level Bypass Relays ‎ (← links)
  • 05000277/LER-1985-025-02, :on 851129,main Turbine Stop Valve Closure Scram & Low Level Group II & III Isolations Occurred.Caused by Misunderstanding of Control Room Alarm & Lack of Adequate Precautions During Troubleshooting ‎ (← links)
  • 05000277/LER-1996-009, :on 961001,declared High Pressure Coolant Injection (HPCI) Sys Inoperable Due to Bearing Misalignment. Realigned Bearing Housing,Performed ST-O-023-200-2 Satisfactorily & Declared HPCI Sys Operable ‎ (← links)
  • 05000277/LER-1985-020-01, :on 850924,low Level Scram Occurred Due to Operator Error.Level Automatically Restored to Normal by Reactor Feedwater Level Control Sys.Operator Counseled ‎ (← links)
  • 05000277/LER-1985-019-01, :on 850919,RHR Pump Declared Inoperable Due to Reduced Performance of Pump in Low Head Region.Cause Undetermined.Pump Reassembled & Tested ‎ (← links)
  • 05000277/LER-1985-024-01, :on 851103,blocking Applied to Drywell Oxygen Analyzer Lines a & B Removed Before Inoperable Primary Containment Isolation Valves Repaired.Caused by Personnel Error.Blocking Restored ‎ (← links)
  • 05000277/LER-1997-002-03, :on 970326,TS Violation Identified as Result of Reactor Operation Slightly in Excess of Licensed Thermal Power.Ctp Calculation Program Was Modified to Compensate for Recirculation Pump Motor Power Factor ‎ (← links)
  • 05000277/LER-1986-004-01, :on 860124,full Scram Occurred When Recirculation Pump 2A Started.Caused by Voltage Transient. Mod Being Pursued to Change Alternate Feed from E-124-R-C to New Static Inverter ‎ (← links)
  • 05000277/LER-1997-001-03, :on 970318,TS Violation Due to non-conservative Average Power Range Monitor Flow Bias Scram Setpoints for Single Loop Operation.Procedural Enhancements to Ensure That Single Loop Flow Conditions,Accommodated ‎ (← links)
  • 05000277/LER-1986-007-01, :on 860203,Group II & III Outboard Isolation Occurred & half-scram Signal Generated During Shutdown. Caused by Erratic Voltage Control by Rheostat.Trips Reset & Motor Generator Returned to Svc ‎ (← links)
  • 05000277/LER-1986-006-01, :on 860201,primary Containment Isolation Sys Group Ii/Iii Outboard Isolation Occurred.Caused by Starting Large Pump Motor While Motor Generator Set Out of Svc. Alternate Feed Changed to Static Inverter ‎ (← links)
  • 05000277/LER-1985-017-01, :on 850825,suppression Pool Vol in Torus Dropped Below Tech Spec Limit.Caused by Use of Torus Water Filter Pump to Reduce Torus Water Vol.Condensate Storage Tank Water Used to Restore Torus Vol ‎ (← links)
  • 05000277/LER-1985-028-02, :on 851227,fuse Supplying Relay Coil Blew. Caused by Stray Strands of Wire in Contact W/Dc Volt. Safety-related Feedwater & Ventilation GE CR-120 Relays Inspected for Stray Wires ‎ (← links)
  • 05000277/LER-1985-026-02, :on 851226,nonconformance W/Tech Spec 3.3.A.2.f Re Control Rod Operability Discovered.Control Rod 30-15 Inserted & 22-1 Withdrawn & Blocked to Repair Leak on Hydraulic Control Unit Accumulator ‎ (← links)
  • 05000277/LER-1985-023-01, :on 850115,determined That Cables for Two Isolation Valves of Same Penetration Shared Common Cable Trays.Condition Not in Conformance W/Electrical Separation Criteria in Fsar.Caused by Personnel Error ‎ (← links)
  • 05000277/LER-1985-022-01, :on 851017,primary Containment Isolation Sys, HPCI Sys & RCIC Sys Actuated Due to Sudden Speed Increase in Feedpumps.Caused by Loose Cable Connector at Feedwater Electric Summer FSUM-2-6-103.Summer Replaced ‎ (← links)
  • 05000277/LER-1979-038-03, /03L-0:on 790812,while at Power,Torus High Vacuum Alarm Sounded.Caused by Clogged Needle Valve Which Bleeds Air to Close Valve A0-2502A.Manual Operation of Needle Valve Relieved Clogging.Bleed Rate Adjusted ‎ (← links)
  • 05000277/LER-1985-012-02, :on 850807,full Scram Resulted from High Neutron Flux Trip on Intermediate Range Monitors C & D. Caused by Personnel Error.General Plant Procedure GP-2 Will Be Revised ‎ (← links)
  • 05000277/LER-1996-011-01, :on 961030,main Steam Line Relief Valve Actuation Occurred Due to Inadvertent Movement of Control Switch.Reactor Operator Immediately Recognized Situation & Reclosed Valve.Event Discussed W/All Crews ‎ (← links)
  • 05000277/LER-1985-011-02, :on 850805,full Scram & Groups II & III Isolations Occurred During Main Turbine Control Valve Surveillance Testing.Caused by Decrease in Relayed Emergency Trip Sys.Signals Reset & Affected Sys Restored ‎ (← links)
  • 05000277/LER-1985-008-02, :on 850725,tests Performed on Fire Barrier Penetrations W/Ceramic fiber-polyurethane Foam Showed Areas W/Polyurethane on Fire Side of Wall Failed Test.Hourly Fire Watches Established ‎ (← links)
  • 05000277/LER-1996-010-01, :on 961006 & 1015,two Automatic Reactor Shutdown Occurred as Result of Main Generator Trip & Lockout Due to Actuation of Negative Sequence Current Protective Relay.Relay Replaced W/Relay of Newer Design ‎ (← links)
  • 05000277/LER-1996-009-02, :on 961001,HPCI Sys Declared Inoperable Due to Bearing Misalignment.Hpci Booster Pump Procedure Will Be Revised to Provide Appropriate Guidance for Bearing Alignment ‎ (← links)
  • 05000277/LER-1985-003, :on 850601 & 03,Loop a RHR Sys Outboard Injection Valve Failed.Caused by Improper Operation.Valve Thrust Assembly Rebuilt & Returned to Svc ‎ (← links)
  • 05000277/LER-1985-018-01, :on 850912,reactor Water Cleanup Sys Inboard & Outboard Suction Valves Closed Due to High Flow Isolation Signal.Caused by Too Rapid Opening of Demineralizer Outlet Valve.Operator Instructed on Proper Procedures ‎ (← links)
  • 05000277/LER-1985-013-01, :on 850812 & 19,Loop a RHR Sys Outboard Injection Valve Declared Inoperable.Caused by Mechanical Interference & Binding in Valve Yoke Assembly.Assembly Rebuilt Following Each Event ‎ (← links)
  • 05000277/LER-1985-006-03, :on 850627,during Cold Shutdown for Refuel & Mod Work,Full Scram on Intermediate Range Monitor High Flux Signal Occurred.Caused by Maint Personnel Working in Subpile Room Bumping Two High Voltage Cables ‎ (← links)
  • 05000277/LER-1985-007-02, :on 850628,reactor Protection Sys & Primary Containment Isolation Sys Initiated Due to False Reactor Low Water Level.Caused by Backfilling Instrument Sensing Lines During Maint.Backfilling Method Reviewed ‎ (← links)
  • 05000277/LER-1985-009-02, :on 850629,full Scram & Groups I,Ii & III Isolation Occurred W/Unit in Cold Shutdown.Caused by False Low Level Signal During Backfilling.Signal Reset & Use of Portable Backfilling Device Suspended ‎ (← links)
  • 05000277/LER-1985-010-02, :on 850629,initiation of ECCS & Diesel Generator Start Occurred W/Unit in Cold Shutdown.Caused by Inadvertent Reactor Low Level Signal.Use of Portable Backfilling Device Suspended ‎ (← links)
  • 05000277/LER-1985-006-02, :on 850624,improper Limitorque Operator Found on Outboard Main Steam Line Drain Valve W/Unit in Extended Refuel Outage.Caused by Personnel Error.Proper Operator Installed & Training Session Conducted ‎ (← links)
  • 05000277/LER-1985-008, :on 850725,determined That Fire Barrier Penetrations Containing Ceramic fiber-polyurethane Foam Unacceptable.Caused by Incorrect Results from Tests Performed on 831103.Barriers Upgraded ‎ (← links)
  • 05000277/LER-1985-016-02, :on 850826,full Scram & Primary Containment Isolation Sys Groups II & III Initiated Due to Reactor Low Level Signal.Caused by Failure to Ensure That Pressure Transmitter Returned to Svc from 850822 Event ‎ (← links)
  • 05000277/LER-1985-015-01, :on 850822,full Scram & Primary Containment Isolation Sys Groups II & III Initiated Due to Reactor Low Level Signal.Caused by Pressure Transmitter PT-53 Block Valve Leak.Block Valve Replaced ‎ (← links)
  • 05000277/LER-1985-004-01, :on 850622,during Cold Shutdown,Actuation of Reactor Protection Sys & Primary Containment Isolation Sys Occurred.Caused by Reactor Level Transmitter Being Returned to Svc & Backfilled.Signals Reset ‎ (← links)
  • 05000277/LER-1985-014-01, :on 850820,scram Signal & Groups II & III Isolation Occurred Due to Low Reactor Water Level.Caused by Slow Response of Controller LIC-8091 & Employee Error. Controller Tuned & Tested ‎ (← links)
  • 05000277/LER-1985-003-02, :on 850603,loop a RHR Sys Injection Valve MO-2-10-154A Declared Inoperable.Caused by Mechanical Binding of Valve Stem in Valve Operator.Valve Operator Rebuilt & Returned to Svc ‎ (← links)
  • 05000277/LER-1985-005-02, :on 850612,w/reactor Mode Switch in Refuel Position,Intermediate Range Monitor Detectors F&B of Neutron Monitoring Sys Inoperable.Caused by Deficiency in Blocking Sequence.Sequence Will Be Revised ‎ (← links)
  • 05000277/LER-1985-002-01, :on 850530,reactor Protection Sys Initiated Scram Signal on Reactor High Pressure During Excess Flow Check Valve Test.Caused by Personnel Response to Leak in Excess Flow Check Valve.Scram Signal Reset ‎ (← links)
  • 05000277/LER-1993-002, :on 930105,discovered That Continuous Firewatch Not in Place,In Violation of TS 3.14.D.2.Caused by Personnel Error.Procedure Used to Control & Track Impairements Will Be Revised ‎ (← links)
  • 05000277/LER-1993-001, :on 930101,HPCI Sys Declared Inoperable Due to Loss of Hydraulic Priming Determined to Be Associated W/Oil Leakage.An Evaluation Will Be Performed to Identify Any Addl Actions Required for Proper Operations of RCIC ‎ (← links)
  • 05000277/LER-1992-022, :on 921021,TS 3.8.C.4.c Violated Resulting from Failure to Perform Continuous Iodine & Particulate Sampling of RB Due to Less than Adequate Review of Monitoring Requirements.Ts Requirements Will Be Reviewed ‎ (← links)
  • 05000277/LER-1992-024, :on 920913,TS Violation Occurred When Reactor Data Not Taken During Plant Shutdown Due to Less than Adequate Human Factors on Test Data Sheet.Surveillance Test & Training Will Be Provided ‎ (← links)
  • 05000277/LER-1985-001, :on 850108,containment Leak Test Program Identified That Total Combined Leakage of Types B & C Tests Exceeded Allowable Leak Rate Limit.Caused by Valves W/Excessive Leakage Rates.Valves Repaired ‎ (← links)
  • 05000277/LER-1992-026, :on 921223,ESW Inlet Sluice Gate Found Not Electrically Blocked Due to Inadequate Administrative Control to Ensure Compliance W/App R Requirements. Administrative Controls Will Be Enhanced ‎ (← links)
  • 05000277/LER-1981-028-01, /01T-0:on 810428,determined That More Detailed Analysis Was Required & Minor Mods Were Necessary to Assure That Certain Fans Would Perform During Earthquakes.Caused by Fan Supports Not Meeting Seismic Requirements ‎ (← links)
  • 05000277/LER-1981-024-03, /03L-0:on 810407,recirculation Pump Drive Flow Increase of 10% within 5 Minutes Was Indicated.Cause Undetermined.Investigation Ongoing.Entire Flow Loop Instrumentation Is Being Calibr ‎ (← links)
  • 05000277/LER-1981-021-03, /03L-0:on 810329,while at Full Power,Drywell Pressure Channel D Found Malfunctioning.Caused by Electronic Failure in Rosemount Model 1151 GP Pressure Transmitter. Circuit Boards on Transmitter Replaced ‎ (← links)
  • 05000277/LER-1981-020-03, /03L-0:on 810325,inboard Containment Radioactive Gas Sampler Isolation Valve SV-2671A Found Leaking.Caused by Plunger Assembly Sticking Due to Dirt Accumulation.Valve Cleaned ‎ (← links)
  • 05000277/LER-1981-018-03, /03L-0:on 810306,local Leak Rate Test Determined Excessive Leakage from Manual Isolation Valve SV-2671A. Caused by Dirt Buildup on Seating Surface,Preventing Proper Valve Disc Seating.Valve Cleaned & Returned to Svc ‎ (← links)
  • 05000277/LER-1981-016-03, /03L-0:on 810225,reactor Core Isolation Cooling Trip Throttle Valve Would Not Reset to Normally Open Position Using Limitorque Operator,Following Manual Trip. Caused by Worn Worm Gear in Trip Throttle Valve Operator ‎ (← links)
  • 05000277/LER-1981-017-03, /03L-0:on 810318,all Inboard Sample Isolation valves,SV-2671A-SV2671G,closed.Caused by Short in Coil of dymo-type Solenoid Valve SV-2671A,which Blew Common Fuse in Control Circuit for All Seven Valves ‎ (← links)
  • 05000277/LER-1981-012-03, /03L-0:on 810202,main Steam Line Monitor D Indicated Low Level Radiation Resulting in Trip Setpoint Above Tech Spec Limit.Caused by Instrument Zero Drift. Monitor Calibr & Returned to Svc ‎ (← links)
  • 05000277/LER-1992-025, :on 921124,E-2 & E-4 EDGs Unexpectedly Started When Wrong Temporary Test Switch Inadvertently Operated During Testing,Due to Personnel Error.St Used to Perform Loss of Power Test Will Be Reviewed ‎ (← links)
  • 05000277/LER-1980-006-03, /03L-0:on 800305,w/both Units at Full Power,One of Two Offsite Power Sources Tripped Due to Loss of Transformer Cooling Fans.Exact Cause Unknown.Cooling Fans Restored,Blown Fuse Replaced & Transformer Tested ‎ (← links)
  • 05000277/LER-1980-007-03, /03L-0:on 800306,while Performing Routine Surveillance Test,Pressure Switch Ps 2-2-134C Setpoint Found Less than 1% Outside of Tech Spec Limit.Caused by Setpoint Drift.Switch Recalibr ‎ (← links)
  • 05000277/LER-1980-005-03, /03L-0:on 800126,while at Power Operation, Surveillance Testing of Diesel Driven Fire Pump Revealed Flow Less than Tech Specs.Caused by Slippage of Throttle Cable Governor,Resulting in Setpoint Drift ‎ (← links)
  • 05000277/LER-1979-036-03, /03L-0 on 790720:setpoint of Differential Pressure Injection Sys 2-14-43B Exceeded Tech Specs.Caused by Differential Pressure Switch Out of Calibr Due to Setpoint Drift.Instrument Recalibr & Returned to Svc ‎ (← links)
  • 05000277/LER-1992-011, :on 920624,discovered Unqualified Fire Barriers During NRC Bulletin 92-001 Review.Caused by Design Defects During Initial Installation of Thermo-Lag Barriers.Fire Watches Established in HPSW Pump Structure ‎ (← links)
  • 05000277/LER-1992-015-01, :on 920817,reactor Scram Occurred Following Main Generator Lock Out.Caused by Less than Adequate Generation & Approval of Substation Load Dispatcher Permit. Isolations Reset & Affected Sys Restored ‎ (← links)
  • 05000277/LER-1996-005-01, :on 960508,determined Units 2 & 3 Operated in Condition Prohibited by TS 3.8.1.Caused by Result of Actuation of Load Tap Changer Surge Protection Circuitry. Alternate Source Replaced ‎ (← links)
  • 05000277/LER-1996-004-01, :on 960417,HPCI Sys Declared Inoperable Due to Leak in Cooling Water Relief Valve.Caused by Igscc.Hpci Cooling Water Relief Valve Was Replaced.W/Undated Ltr ‎ (← links)
  • 05000277/LER-1992-023, :on 921028,hourly Firewatches for Emergency Switchgear & Motor Generator Rooms Not Performed Per TS Due to Personnel Error.Training Will Be Conducted Re Aspects of Firewatch Insps ‎ (← links)
  • 05000277/LER-1992-021, :on 921015,TS Violation Occurred When Two of Eleven MSRVs & One of Two SVs Did Not Lift within TS 1% Tolerence.Caused by Main Steam Relief & Safety Valve Setpoint Drift.Refurbished Valves Installed ‎ (← links)
  • 05000277/LER-1992-019, :on 921005,determined That Plant Outside Design Basis Due to Potential Loss of Containment Cooling Due to Valve Yoke Cracking.Appropriate Corrective Actions Will Be Implemented as Necessary ‎ (← links)
  • 05000277/LER-1992-020, :on 921006,CR Ventilation Sys Transferred to Emergency Ventilation Mode Due to an Instrument Spike in B Main CR Radiator Monitor.Design Work in Progress for Mod.W/ ‎ (← links)
  • 05000277/LER-2020-001, Emergency Diesel Generator Shutdown Due to Intercooler Low Pressure Results in Condition Prohibited by Technical Specifications ‎ (← links)
  • 05000277/LER-1992-017, :on 920912,APRM Surveillance Missed Due to Less than Adequate Implementation of Change in Performing Soft Shutdowns.Soft Shutdowns Will Be Evaluated as Plant Evolution/Special Test ‎ (← links)
  • 05000277/LER-1992-016-01, :on 920911,discovered That Containment Venting & Outgoing Activities Had Been Started While SBGTS Awas Removed from Svc & Inoperable.Caused by Personnel Error. Containment de-inerting Terminated ‎ (← links)
  • 05000277/LER-1992-018, :on 920915,security Personnel Discovered That TS Required 1 H Firewatch Performed in Excess of 1 H Interval.Caused by Personnel Error.Security Supervisor Counselled ‎ (← links)
  • 05000277/LER-1996-007-01, :on 960604,ESFA Occurred Due to Loss of One off-site Electrical Source as Result of off-site Substation Activities.Reset Isolation Logics & Restored Affected Sys ‎ (← links)
  • 05000277/LER-1992-011-01, :on 920625,review of NRC Bulletin 92-001 Re Failure of Thermo-Lag 330 Fire Barrier Sys Completed & Fire Barriers Delineated in Bulletin Declared Inoperable.Caused by Design Deficiencies.Fire Watch Established ‎ (← links)
  • 05000277/LER-1992-012-01, :on 920717,reactor Scram Occurred When Main Generator Output Breaker Tripped Open & Caused Main Generator Power Load Unbalance Trip Signal.Caused by Severe Thunderstorm.Scram & Isolations Reset ‎ (← links)
  • 05000277/LER-1992-010-01, :on 920704, 1 Auto Transformer Failed & 3 Startup Feed Lost When Breaker Tripped Open.Caused by Defective E-313 Breaker Control Switch.Affected Sys Restored to Appropriate Conditions as Necessary ‎ (← links)
  • 05000277/LER-1996-006-01, :on 960522,Unit 2 RPS Power Supply Unexpectedly Lost.Caused by Human Performance.Rps Bus Supply Restored & Operator Involved in Event Coached on self-checking Practices.W/Undated Ltr ‎ (← links)
  • 05000277/LER-1995-006, :on 951022,offsite Electrical Power Source Lost.Caused by Momentary Deenergization of Several Electrical Distribution Panels.Isolation Logics Reset & Affected Sys Restored ‎ (← links)
  • 05000277/LER-1992-014-01, :on 920812,TSs Violated When Calculated Core Thermal Power Limit Exceeded.Caused by Lower than Actual Feedwater Flow Input Into Process Computer.Process Computer Software Will Be Changed ‎ (← links)
  • 05000277/LER-1996-003-01, :on 960228,ESFA Occurred Due to Loss of One off-site Power Source.Reset PCIS Group II Isolation Logics & Restored Affected Sys.W/Undated Ltr ‎ (← links)
  • 05000277/LER-1992-008, :on 920430,determined That Circulating Water Composite Samplers Were Out of Svc.Caused by Equipment Malfunction.Circulating Water Intake & Discharge Sampling Devices Have Been Repaired & Returned to Svc ‎ (← links)
  • 05000277/LER-1996-002-01, :on 960126,TS Violation Occurred When Certain Emergency Bus Protection Relays Found Out of Calibr Due to Inadequate Testing Methodology.Recalibrated Affected Relays to within Appropriate TS Limits ‎ (← links)
  • 05000277/LER-1996-001-01, :on 960118,licensed Thermal Power Slightly Exceeded Due to Unaccounted for CRD Water Flow.Caused by Failure to Consider Impact of Addl Flow on Core Thermal Power.Mod Design Process Will Be Enhanced.W/Undated Ltr ‎ (← links)
  • 05000277/LER-1979-002-01, /01T-0 on 790108:cable Spreading Room Cardox Sys Disabled W/O Firewatch Present.Absence Due to Failure of Personnel to Notify Shift Supervisor Upon Work Completion ‎ (← links)
  • 05000277/LER-1992-009-01, :on 920520,reactor Scram Occurred When Two Turbine CIV Closed Simultaneously Causing Power Trip Signal. Cause Determined to Be Unexpected Closure of Intercept Valve 2.Sys Reset & Returned to Normal ‎ (← links)
  • 05000277/LER-1984-015, :on 840709,smoke Detector Alarms Activated W/O Cause.Hourly Fire Patrol Established & Detectors Removed, Violating Tech Spec 3.14.D.3 Rev.Personnel Will Review Tech Spec Revs to Avoid Deviation ‎ (← links)
  • 05000277/LER-1984-016, :on 840727,liquid Penetration Exams of Reactor Pressure Vessel Jet Pump Inlet Riser Safe Ends Revealed crack-like Indications.Caused by Igscc.Addl Radiographic & Liquid Dye Penetrant Exams Will Be Performed ‎ (← links)
  • 05000277/LER-1992-006, :on 920407,reactor Scram Initiated When Weld Leak Discovered on 1-inch Vent Line & Line Could Not Be Isolated.Caused by High Frequency Vibration on Line.Scram & Isolation Logics Reset & Weld Repaired ‎ (← links)
  • 05000277/LER-1992-007, :on 920407,determined That Monthly Samples of Reactor Bldg Ventilation Stack & Main Stack Sys Particulate Filters Not Analyzed for Alpha/Beta Activity.Caused by Loss of Samples by Teledyne.Storage Revised ‎ (← links)
  • 05000277/LER-1992-005, :on 920326,2B Reactor Water Level Reference Leg Condensing Chamber Was Declared Inoperable.Caused by Loss of Inventory in 2B Condensing Chamber.Leaks Were Repaired & Instrument Lines Were Backfilled ‎ (← links)
  • 05000277/LER-1984-014, :on 840716,continuous Firewatch Removed from Cable Spreading Room W/O Realizing That Firewatch Still Needed Due to out-of-svc Cardox Sys.Condition Discovered & Firewatch Reestablished on 840719 ‎ (← links)
  • 05000277/LER-1992-004-02, :on 920317,HPCI Was Determined Inoperable Due to Isolation of HPCI Turbine Exhaust Drain Line.On 920316, Outboard Isolation Valve Closed Due to Inoperability of Inboard Isolation Valve.Valves Repaired ‎ (← links)
  • 05000277/LER-1992-001-03, :on 920310,determined That PCIS LSFT for Group III Isolation Defeated Automatic Capability of PCIS Group III Channels.Caused by No Formal 10CFR50.59 Review Being Performed.Pcis & LSFT Were Deleted ‎ (← links)
  • 05000277/LER-1995-006-02, :on 951022,transfer of Startup Circuits Resulted in PCIS Group II Half Isolation on Both Units Due Loss of One Offsite Power Source.Pcis Group II Isolation Logics Reset & Affected Sys Restored.W/Undated Ltr ‎ (← links)
  • 05000277/LER-1984-011, :on 840608,acetylene Leak Occurred During Drywell Preheat Welding.Caused by Leak Where Hose Crimped to Std Screw Connection.Personnel Evacuated & Addl Ventilation Used to Expel Gas ‎ (← links)
  • 05000277/LER-1984-012, :on 840628,w/unit in Cold Shutdown for Refueling,Surveillance Testing Discovered Inoperable Horizontal Fire Damper in Cable Spreading Room.Caused by Missing Spring Closure Device ‎ (← links)
  • 05000277/LER-1984-010, :on 840607,w/unit Shutdown for Refueling & Major Mod outage,through-wall Crack Discovered in Loop a Jet Pump Instrumentation Penetration Reducer to safe-end Weld.Caused by IGSCC ‎ (← links)
  • 05000277/LER-1995-005-02, :on 950922,discovered That Narrow Range Indication on Dwl Pr (PR-2(3)508) Being Checked Instead of Wide Range Indicator Required by Ts.Surveillance Tests Associated W/Monitoring Parameters Changed.W/Undated Ltr ‎ (← links)
  • 05000277/LER-1984-008-01, Revised LER 84-008-01:on 840427,standby Gas Treatment Sys Solenoid Valve SV-00009 Failed to Operate Properly, Preventing Fan a Inlet & Outlet Dampers from Opening.Cause of Solenoid Failure Under Investigation ‎ (← links)
  • 05000277/LER-1984-013, :on 840629,diesel Driven Fire Pump Started Automatically & Flooding Occured at Elevation 116 Ft of Turbine Bldg.Caused by Break in Elbow in Fire Header.Both Fire Pumps Removed from Svc & Tested ‎ (← links)
  • 05000277/LER-1995-003-03, :on 950815,unplanned ESF Actuation Occurred When Wire Was Out in Junction Box.Evaluated Addl Labelling & Print Revs ‎ (← links)
  • 05000277/LER-1995-004-02, :on 950814,TS Violation Occurred When RWCU Temp Switch Was Inoperable Due to Design Deficiency.Revised Calibr Sheet for TIS-2-12-099 to Add Note to Ensure Proper Installation of Thermistor ‎ (← links)
  • 05000277/LER-1984-009, :on 840516,during Refueling Outage,False lo-lo Reactor Level Initiation Signal Caused HPCI & RCIC to Attempt to Start When Both Power Supplies for ECCS Channel a Logic Feeds Removed.Supply Feeds Restored ‎ (← links)
  • 05000277/LER-1984-008, :on 840427,solenoid Valve SV-00009 of Standby Gas Treatment Sys Failed.Caused by Measurement Error of Differential Pressure Switch.Defective Solenoid Replaced & Switches Will Be Replaced & Tested ‎ (← links)
  • 05000277/LER-1995-001-03, :on 950609,E-2 DG Output Breaker Tripped Open. Loss of Power to 4kV Bus Caused Group II & III Isolation. Caused by Inadequate Review of Routine Test RT-0-052-252-2. PCIS Logic Reset & Affected Sys Restored.W/Undated Ltr ‎ (← links)
  • 05000277/LER-1991-037, :on 911104,Channel B Reactor Protection Sys half-scram Occurred When Motor Generator Set 2B Output Breaker Tripped.Caused by Undervoltage Condition Due to Degraded Diodes.Diodes Replaced & Scram Reset ‎ (← links)
  • 05000277/LER-1991-036, :on 911103,discovered That Waste Sample Tank a Treated Liquid Released W/O Appropriate Sample & Release Approval.Caused by Failure to Properly Follow Surveillance Test Requirements.Liquid Sample Obtained ‎ (← links)
  • 05000277/LER-1992-003-01, :on 920313,determined That RHR Pumps 2B & 2D Could Have Potentially Been Placed in Inoperable Condition Had Low Energy Pipe Failed in RHR Rooms.Cause Not Determined.Discharge Check Valves Installed ‎ (← links)
  • 05000277/LER-1992-002-02, :on 920311,EDG E-3 Started in 13 Instead of 10 Requirement in Updated Fsar.Caused by Improperly Primed Oil Filter After Filter Replacement.Info Tags Hung on All EDG Fuel Oil Filters & Training Held ‎ (← links)
  • 05000277/LER-1991-009-01, :on 910420,primary Containment Isolation Sys Isolation Occurred.Caused by Failure of Startup Emergency Feed Cable 2.Cables Replaced ‎ (← links)
  • 05000277/LER-1983-025-03, /03L-0:on 831229,outboard MSIV AO-2-2-86B Fast Closure Time Was 5.5 S.Caused by Insufficient Flow Through Fast Closure Needle Valve on Oil Dashpot.Valve Readjusted & Retested ‎ (← links)
  • 05000277/LER-1984-004-01, :on 840213,during Local Leak Rate Tests on RHR Sys B Valves,Packing Leak Discovered on Test Line Isolation Valve MO2-10-34B.Caused by Loose Packing.Packing Tightened & Valve Stroke Tested ‎ (← links)
  • 05000277/LER-1991-038, :on 911205,unexpected Engineered Safety Feature Actuation Occurred During Performance of Surveillance Test. Caused by Spurious Actuation of RCIC Isolation Logic.Test Reperformed W/No Adverse Effects ‎ (← links)
  • 05000277/LER-1991-039, :on 911206,excessive Leakage Noted in RHR Sys B Loop Injection Check Valve &/Or Associated Bypass Valve. Caused by Obstruction in Valve Seating Area.Valve Disassembled & Repaired ‎ (← links)
  • 05000277/LER-1984-001, :on 840117,during Surveillance Testing of RHR B Injection Valve Mo 2-10154B,valve Failed to Reopen.Caused by Warping of Bakelite Coil & Core Housing within Motor Control Ctr.Thermal Overload Device Replaced ‎ (← links)
  • 05000277/LER-1995-002-01, :on 950618,condition Was Prohibited by TS When Two DGs Inoperable at Same Time Due to 59G Relay Issue. Corrected Wiring Discrepancy on E-2D/G & Completed Performance of Post Maint Test ‎ (← links)
  • 05000277/LER-1983-026-03, /03L-0:on 831205,during Startup,Moisture Monitoring Sys Failed While Undergoing Surveillance Testing. Caused by Improperly Positioned Potter & Brumfield Relay Model R10-EL-W2-V700.Relay Readjusted ‎ (← links)
  • 05000277/LER-1983-023-01, /01X-1:on 831108,combined Leakage for Type B & C Tests Exceeded 10CFR50,App J Limit & Containment Isolation Valves MO-2-74 & MO-23-57 Failed Local Leak Rate Test. Caused by Normal Wear of Valve Internals ‎ (← links)
  • 05000277/LER-1976-008-03, /03L:on 760109,rod Withdraw Permissive Light Blinked on While Refuel Crane Over Core.Caused by Limit Switch CR115G307 Closing & Opening on Low Spots on Camming Surface.Switch Adjusted to Remain Open Over Surface ‎ (← links)
  • 05000277/LER-1976-004-01, /01T:on 760115,RHR Injection Valve MO-10-25A Failed to Open.Caused by Sheared Pinion Gear Key Due to Binding of Valve.Operator & Pinion Gear Replaced & Torque & Limit Switches Adjusted ‎ (← links)
  • 05000277/LER-1976-014-01, /01T:on 760303,recombiner Mechanical Compressor 2B Leak Rate Exceeded Allowable Limits.Caused by Numerous Leaks Associated W/Compressor Head O-rings & Valve covers.O-rings Replaced & Valve Covers Lightened ‎ (← links)
  • 05000277/LER-1977-005-01, /1P:on 770114,high Pressure Svc Water,Emergency Svc Water & Emergency Cooling Water Pumps Did Not Meet FSAR Seismic Requirements.Caused by Change in Calculation Techniques.Higher Strength Bolts & Restraints Added ‎ (← links)
  • 05000277/LER-1976-048-03, /03L:on 760618,RHR Inboard Shutdown Cooling Suction Isolation Valve MO-2-10-18 Failed to Stroke.Caused by Insufficient Thread Engagement of Bolts Connecting Valve Yoke to Operator.Valve Replaced,Stroked & Tested ‎ (← links)
  • 05000277/LER-1976-057-01, /01T:on 760722,three Hydraulic Shock Suppressors on Main Steam Relief Valve Discharge Lines Found W/Empty Reservoirs.Caused by Defective Seals & O-rings.Defective Parts Replaced & Suppressors Tested ‎ (← links)
  • 05000277/LER-1976-066-01, /01T:on 760902,individual LPCI Pump Flows Limited by Valving to Approx 10,200 Gpm While 10,900 Gpm Required. Caused by Lack of Communication Between NSSS & Licensee. Valve Will Be Corrected After Review ‎ (← links)
  • 05000277/LER-1976-067-03, /03L:on 760908,containment Spray Permissive Switch LIS-2-2-3-73A Found Inoperative.Caused by Cracked Bellows on Yarway Model 4418CE Level Switch.Switch Repaired & Returned to Svc ‎ (← links)
  • 05000277/LER-1976-068-01, /01T:on 760921,trip Level Setting for Permissive Core Spray,Lpci Injection & Recirculation Pump Discharge Valve Set at Improper Level.Caused by Inadequate Communication Between NSSS & Licensee ‎ (← links)
  • 05000277/LER-1976-069-01, /01T:on 760925,gaseous Release Rate Above Allowable Limit.Caused by Vacuum Pump Trip During Flooding of Condenser.Condenser Inventory Vented Via Vacuum Breakers to Turbine Bldg ‎ (← links)
  • 05000277/LER-1976-071-03, /03L:on 761005,RCIC Trip Throttle Valve Would Not Reset After Trip.Caused by Grounded Wire on Trombetta Trip Solenoid Model G-206.Solenoid Repaired ‎ (← links)
  • 05000277/LER-1976-072-03, /03L:on 761005,setpoint of Automatic Depressurization Sys Confirmatory Low Level Switch LIS 2-2-2-83A Was 0.85 Inches Lower than 6-inch Tech Spec Limit.Caused by Slight Setpoint Drift.Switch Recalibr ‎ (← links)
  • 05000277/LER-1976-073-03, /03L:on 760914,HPCI Steam Line High Flow Switch DPIS 2-23-76 Trip Setting Exceeded Tech Spec Limit.Caused by Setpoint Shift.Switch Recalibr & Retested ‎ (← links)
  • 05000277/LER-1976-074-03, /03L:on 761101,control Room Radiation Sampling Sys Low Flow Alarm & Low Flow Isolation Signal Not Received from Flow Switches FS-0760 a & B.Caused by Wiring Error.Wiring Error Corrected,Alarm Tested Successfully & Test Rewri ‎ (← links)
  • 05000277/LER-1976-075-03, /03L:on 761109,core Spray a Full Flow Test Return Valve MO-26A Failed to Close.Caused by Motor Operator Gear Train Failure.Valve Operator Replaced & Valve Operated Properly ‎ (← links)
  • 05000277/LER-1976-076-03, /03L:on 761018,third Quarter Average Release Rate for Iodine & Particulates Exceeded Tech Spec Limit.Caused by Minor Leakage of Primary Coolant from Valve Packing,Pump Seals & HX Flanges in Reactor Water Cleanup Sys ‎ (← links)
  • 05000277/LER-1976-077-01, /01T:on 761114,main Steam Relief Valve 71F Failed Open.Caused by Dirt Under Pilot Disk & Seat,Leading to Seat Leakage & Cutting,Precipitating Valve Lifting.Plant Shut Down & Relief Valve Replaced ‎ (← links)
  • 05000277/LER-1976-078-03, /03L:on 761115,PS-2-2-134B & PS-2-2-134A Tripped at 845 Psig & 860 Psig,Respectively.Caused by Setpoint Shift.Switches Recalibr ‎ (← links)
  • 05000277/LER-1976-079-01, /01T:on 761117,three Hydraulic Snubbers Found W/Empty Reservoirs.Caused by Leaking Fittings.New Gaskets Installed,Reservoirs Repaired & Refilled & Snubbers Tested Successfully Prior to Reinstallation ‎ (← links)
  • 05000277/LER-1976-080-03, /03L:on 761118,outboard MSIV Failed to Close During Surveillance Testing Due to Backseat Deformation. Caused by Valve Stem Gauging & Preventing Free Valve Movement.Valve Repaired & Tested Satisfactorily ‎ (← links)
  • 05000277/LER-1976-081-03, /03L:on 761228,RCIC Steam Supply Isolation Valve MO-13-16 Failed to Respond to Auto Open Signal During Routine Surveillance Testing.Caused by Valve Motor Damage Due to Failure of Torque Switch.Motor & Switch Replaced ‎ (← links)
  • 05000277/LER-1976-083-03, /03L:on 761207,TIP 2 Machine Shield Limit Switch Tripped W/Tip Detector in Core,Causing Isolation Ball Valve to Close & Prevent Withdrawal of TIP Probe.Switch Readjusted & Proper TIP Operation Confirmed ‎ (← links)
  • 05000277/LER-1976-084-03, /03L:on 761217,HPCI Steam Line High Flow Switch DPIS-2-23-76 Found Higher than Tech Spec Limit.Caused by Setpoint Shift.Switch Recalibr & Tested Satisfactorily ‎ (← links)
  • 05000277/LER-1976-015-01, /01T:on 760304,gaseous Release Rate Exceeded Tech Spec Limit.Caused by Backwash Delay.Mod Currently Under Investigation Would Direct Backwash Venting to Hotwell, Allowing Gaseous Effluent Benefit of Offgas Sys ‎ (← links)
  • 05000277/LER-1976-016-03, /03L:on 760309,drywell Radiation Monitor Had No Sample Flow.Caused by Defective Coil.Coil Replaced & Sys Returned to Normal Operation ‎ (← links)
  • 05000277/LER-1976-018-01, /01T:on 760329,gaseous Release Rate Exceeded Rate Allowable.Caused by Depressurization of Reactor to Main Condenser.Release Rate Returned to Normal,Vacuum Established & Depressurization Restarted ‎ (← links)
  • 05000277/LER-1976-019-03, /03L:from 760315 to 760328,RHR HX 2A Leak Permitted Radioactive Water to Leak from Condensate Storage Transfer Sys to River.Caused by Two Leaking Tubes & Failed Internal Bellows ‎ (← links)
  • 05000277/LER-1976-021-03, /03L:on 760329,leakage of Feedwater Check Valves, Inboard 28A & 28B & Outboard 96A & 96B Discovered. Caused by Rust Scale on Seating Surfaces of Valve Seat & Flapper.Valves Inspected,Relapped & Returned to Svc ‎ (← links)
  • 05000277/LER-1976-023-03, /03L:on 760405,drywell High Pressure Switches PS-2-10-101C & PS-2-10-119C Found Valved Out of Svc.Caused by Personnel Error.Verification of Valve Lineup After Tests Emphasized ‎ (← links)
  • 05000277/LER-1976-024-03, /03L:on 760408,control Room Radiation Monitor RIS-0760A Failed in Low Count Direction.Caused by Logic Chip Vibrating Out of Socket.Logic Chip Reinserted & Unit Operated Properly ‎ (← links)
  • 05000277/LER-1976-026-03, /03L:on 760327,torus Vol Found Below Allowable Limit of Tech Spec.Caused by Operator Inadvertently Permitting Level to Drop Below Limit.Vol Restored to Normal ‎ (← links)
  • 05000277/LER-1976-027-03, /03L:on 760409,relief Valve Bellows Leak Detector Switch PS-2-2-71L Failed to Trip as Result of Broken Wire Connector to Switch.Connector Replaced ‎ (← links)
  • 05000277/LER-1976-028-01, /01T:on 760413,review of RHR Logic Identified Design Deficiency Which Would Result in Starting of Only Two Pumps During LOCA Concurrent W/Loss of Offsite Power. Circuitry Modified & Tested to Verify Proper Operation ‎ (← links)
  • 05000277/LER-1976-029-03, /03L:on 760423,setpoint of Secondary containment- to-torus Vacuum Breaker DPIS-2503B Switch Found to Be 0.011 Psid Above Tech Spec Limit.Caused by Setpoint Drift.Switch Recalibr & Returned to Svc ‎ (← links)
  • 05000277/LER-1976-030-01, /01T:on 760428,two Hydraulic Snubbers on HPCI Sys Found Inoperable Because of Empty Reservoirs.Caused by Defective Seals & O Rings.Defective Parts Will Be Replaced & Snubbers Tested ‎ (← links)
  • 05000277/LER-1976-031-01, /01T:on 760428,11 Hydraulic Snubbers on Main Steam Relief Valve Discharge Lines Found Inoperable.Ten Inoperable Because of Empty Reservoirs & One Because of Rotated Reservoir.Caused by Defective Seals & O Rings ‎ (← links)
  • 05000277/LER-1976-032-01, /01T:on 760428,two Hydraulic Snubbers on Main Steam Line Ring Header Found Inoperable Due to Empty Reservoirs.Caused by Defective Seals & O Rings.Defective Parts Will Be Replaced & Snubbers Tested ‎ (← links)
  • 05000277/LER-1976-033-01, /01T:on 760428,hydraulic Snubber SS-2-B on Recirculation Pump Sys Found Inoperable Due to Empty Reservoir.Caused by Defective Seals & O Rings.Defective Parts Will Be Replaced & Snubbers Tested ‎ (← links)
  • 05000277/LER-1976-034-01, /01T:on 760428,snubber on Reactor Water Cleanup Sys Found Inoperable Due to Empty Reservoir.Caused by Defective Seals & O Rings.Defective Parts Will Be Replaced & Snubber Will Be Tested ‎ (← links)
  • 05000277/LER-1976-035-01, /01T:on 760428,two Hydraulic Snubbers on Core Spray Sys Found Inoperable Due to Fluid Reservoirs Rotated to Horizontal Position.Cause Not Determined.Snubbers Being Repaired & Will Be Tested ‎ (← links)
  • 05000277/LER-1976-036-01, /01T:on 760428,three Hydraulic Snubbers on Feedwater Sys Found Inoperable.Two Snubbers Failed Because of Rotated Reservoir.Snubbers Repaired or Will Be Repaired ‎ (← links)
  • 05000277/LER-1976-037-03, /03L:on 760426,reactor Level Switch LIS 2-2-3-101B Observed to Bounce When Trip Signal Applied.Caused by Defective Microswitch in Barton Model 288A Level Indicating Switch.Microswitch Replaced,Recalibr & Tested ‎ (← links)
  • 05000277/LER-1976-039-03, /03L:on 760507,required Source Range Monitor Surveillance Test Not Done Due to LPRM String Replacement. Importance of Test Completion Emphasized to Personnel ‎ (← links)
  • 05000277/LER-1976-040-03, /03L:on 760509,gamma Scan Not Performed Prior to Two Liquid Effluent Releases.Caused by Lack of Radwaste Storage Capacity.Beta Activity Reviewed Prior to Release. Based on Previous Data,Limit Would Not Be Exceeded ‎ (← links)
  • 05000277/LER-1976-041-03, /03L:on 760519,reactor Recirculation Pump a Discharge Valve MO-2-02-53A Could Not Be Closed Following Minor Mod of Valve Control Circuit.Caused by Broken Wire in Closing Control Circuit.Broken Wire Repaired ‎ (← links)
  • 05000277/LER-1976-042-03, /03L:on 760528,three Liquid Radwaste Releases Made W/Gross Activity Recorder Inoperable.Caused by Defective GE 1095K66707 Recorder Amplifier.Amplifier Replaced & Monitor & Recorder Recalibr & Returned to Svc ‎ (← links)
  • 05000277/LER-1976-046-01, /01T:on 760629,all Four Recombiner Hydrogen Analyzers Found Valved Out of Svc.Caused by Procedural Deficiency.Plant Procedures Revised ‎ (← links)
  • 05000277/LER-1976-047-01, /01T:on 760629,main Steam Relief Valve Failed Open.Caused by Pilot Valve Seat Leakage.Relief Valve Replaced ‎ (← links)
  • 05000277/LER-1976-049-03, /03L:on 760619,failure of Common Power Supply to Refuel Floor Exhaust Vent Radiation Monitor & Reactor Bldg Exhaust Vent Radiation Monitor Caused Downscale Failures. Power Supply Replaced.Monitors Returned to Svc ‎ (← links)
  • 05000277/LER-1976-051-01, /01T:on 760711,sample Flow to Main Stack Sampling Sys Disturbed When Lightning Blew Fuses in Flow Control Valve Circuitry.Damaged Components & Blown Fuses Replaced ‎ (← links)
  • 05000277/LER-1976-052-03, /03L:on 760710,probe 1 Stopped 1 Inch Before Reaching Preset Shield Limit During Withdrawal & Machine Ball Valve Did Not Close.Probe Machine Shield Limit Switch Operated Spuriously Causing Incomplete Withdrawal ‎ (← links)
  • 05000277/LER-1976-053-03, /03L:on 760712,second Quarter Average Release Rate for Iodine & Particulate Exceeded Tech Spec.Caused by Shutdown & Depressurization for Refueling ‎ (← links)
  • 05000277/LER-1976-054-01, /01T:on 760719,HPCI Turbine Speed Could Not Be Controlled by Controller or Test Pot.Caused by Two Defective 2166 Zener Diodes & Defective 747 Integrated Circuit Chip in Ramp Generator & Signal Converter Assembly ‎ (← links)
  • 05000277/LER-1976-055-01, /01T:on 760726,tripping of Reactor Bldg Ventilation Fans Resulted in Increase of Steam Tunnel Temp. Caused by Ventilation Sys Transient.Trip Points Returned to Normal & Recalibr After Ventilation Sys Returned to Svc ‎ (← links)
  • 05000277/LER-1976-056-03, /03L:on 760803,control Room Ventilation Radiation Monitor RIS-0160A Displayed Abnormal Reading.Caused by Failure of Integrating Circuit in Exponent Counting Circuit of Trapelo DRM-100 Digital Process Radiation Monitor ‎ (← links)
  • 05000277/LER-1976-058-01, /01T:on 760820,torus Vol Fell Below Tech Spec Level.Caused by Defective Positioner on Control Valve Returning Condensate to Torus.Valve Positioner Repaired & Valve Returned to Svc ‎ (← links)
  • 05000277/LER-1976-059-03, /03L:on 760824,outboard Drywell Purge Exhaust Valve A0-2507 Found Partially Closed.Caused by Sheared Alignment Key.Valve & Actuator Realigned & New Key Installed ‎ (← links)
  • 05000277/LER-1976-060-03, /03L:on 760821,improper Sample Obtained from Drywell Radioactive Gas Sampling Sys Due to Leakage.Caused by Loose Fitting on Electrical Penetration.Fitting Tightened ‎ (← links)
  • 05000277/LER-1976-061-03, /03L:on 760823,drywell Radioactive Gas Sample Pumps Tripped & Sample Sys Isolated,Removing Sys from Svc. Relay GE CR120AD04041AA Failed in Fail Safe Position.Relay Replaced & Sys Returned to Svc ‎ (← links)
  • 05000277/LER-1976-062-01, /01T:on 760825,suppressor on Main Steam Relief Valve Discharge Line C Found W/Empty Reservoir.No Apparent Cause Found.Suppressor Refilled & Leak Checked Prior to Reinstallation ‎ (← links)
  • 05000277/LER-1976-063-01, /01T:on 760825,suppressor on Recirculation Pump B Found W/Empty Reservoir.Caused by Broken Sight Glass.Site Glass Replaced & Suppressor Refilled & Checked for Leaks ‎ (← links)
  • 05000277/LER-1976-064-03, /03L:on 760829,containment Atmosphere Dilution Sys Declared Inoperable Because Liquid Nitrogen Tank Relief Valve Failed to Reseat,Blowing Down Content Below Limits. Blowback Ring Replaced ‎ (← links)
  • 05000277/LER-1976-065-36, /03L:on 760828,APRM a Trip Points Found to Be Less Conservative than Tech Spec Required W/Reactor in Run Mode. Caused by Instrument Drift.Aprm Recalibr & Returned to Svc ‎ (← links)
  • 05000277/LER-1977-001-01, /01T:on 770104,reservoirs of Hydraulic Snubber Relief Valves RV-71E & SS-C6 Found Empty.Caused by Reservoir Leak & Loose Locking Nut Allowing Unit to Turn Upside Down. Repairs Made & Reservoirs Filled ‎ (← links)
  • 05000277/LER-1977-002-03, /03L:on 770102,control Rods 30-27 & 54-23 Did Not Fully Insert on Auto Scram Signal.Cause Undetermined.Rods Successfully scram-timed & friction-tested ‎ (← links)
  • 05000277/LER-1977-003-01, /01T:on 770103,insp of Four Relief Valves Revealed Delamination & Overheating of Air Operator Diaphragms.Cause Not Stated.Diaphragms Replaced ‎ (← links)
  • 05000277/LER-1977-004-01, /01T:on 770106,main Steam Relief Valve 71E Failed Open.Caused by Excessive Pilot Valve Seat Leakage.Valve 71D Replaced.Pilot Valve Section Replaced on Valves 71E & 71K ‎ (← links)
  • 05000277/LER-1977-006-03, /03L:on 770111,transient in-core Machine Probe Travelled Beyond in-shield Limit Switch During Withdrawal. Caused by Personnel Misoperation & Short Circuit in Backup Circuit.Short Corrected ‎ (← links)
  • 05000277/LER-1977-007-03, /03L:on 761121,rod Block Monitor Functional Surveillance Test Not Performed for Nov 1976.Caused by Personnel Error.Test Performed on Schedule in Dec ‎ (← links)
  • 05000277/LER-1991-035, :on 911025,trip of Emergency Bus Breaker Caused Automatic Fast Transfer Resulting in CR Emergency Ventilation Sys Actuation.Caused by Personnel Incorrectly Installing Test Equipment.Personnel Counseled ‎ (← links)
  • 05000277/LER-1991-034, :on 911021,TS Violation Occurred When Mode Switch Was Placed in Startup Position W/Rcic Sys Inoperable & on 911022,RCIC Flow Controller Output Signal Identified to Be 0% Instead of 100% ‎ (← links)
  • 05000277/LER-1991-033, :on 911015,drywell Pressure & Temp Increase Identified When High Pressure Coolant Injection Steam Supply Inboard Isolation Valve Stroked.Caused by Excessive Valve Packing Leakage Due to Gouged Stem ‎ (← links)
  • 05000277/LER-1991-032, :on 910917,18 & 24,control Room Ventilation Sys Transferred to Emergency Ventilation Mode Due to Instrument Spikes in Main Control Room Radiation Monitor B.Caused by Wire Connector Short.Procedure Revised ‎ (← links)
  • 05000277/LER-1991-021, :on 910624,pressure Transmitters Determined to Be non-seismically Supported.Caused by Improper Rack Installation.On 910909,incorrect Root Valve Closed Due to Labeling Error.Labels Corrected ‎ (← links)
  • 05000277/LER-1991-026, :on 910727,actuations Occurred on Primary Containment Isolation Sys When 4 Kv Emergency Bus Transferred to Startup Feed.Caused by Phase B Arcing. Isolations Reset & Disconnect Repaired ‎ (← links)
  • 05000277/LER-1991-025, :on 910728,isolation of HPCI Sys Occurred During Performance of Surveillance Test,Resulting in ESF Actuation.Caused by Failure to Follow Procedures & Procedural Weaknesses.Procedures Revised ‎ (← links)
  • 05000277/LER-1991-023, :on 910702,control Room Ventilation Sys Transferred to Emergency Ventilation Mode Due to Component Failure.Mod Initiated to Replace Existing Instrumentation ‎ (← links)
  • 05000277/LER-1991-022, :on 910627,manual Scram Occurred Due to Loss of Condenser Vacuum Following Isolation of Offgas Recombiner. Caused by Relief Valve Lifting Prematurely.Valve Replaced & Setpoint Verified to Be Correct ‎ (← links)
  • 05000277/LER-1983-004-03, /03L-0:on 830424,refueling Floor Ventilation Radiation Monitor RE2-17-432D Experienced Downscale Spike. Caused by Defective Gieger/Mueller Tube.Tube Replaced & Faulty Connector Rebuilt ‎ (← links)
  • 05000277/LER-1984-003-01, Revised LER 84-003-01:on 840131,heatup Rate Exceeded Tech Spec Limits.Caused by Personnel Error.Operator Disciplined. Memo Issued to All Licensed Operators Re Tech Spec Rate ‎ (← links)
  • 05000277/LER-1984-007, :on 840403,reactor Water Cleanup Sys Isolated on High Temp.Caused by Loss of Electrical Power to Temp Indicating Switch TIS-12-99.Maint Shorted Hot Lead to Ground Causing Fuse 12A-F1 to Blow.Fuse Replaced ‎ (← links)
  • 05000277/LER-1984-006, :on 840328,routine Sample of Water Taken from High Pressure Svc Water Piping Discovered Contaminated. Caused by HX Leaking Into Discharge Pond Via Piping Sys. HX Repaired ‎ (← links)
  • 05000277/LER-1984-002-01, :on 840321,partial Actuation of Primary Containment Isolation Sys Caused Main Steam Tunnel Ventilation Trip.Caused by Burned Out Coil in Relay 16A-K24. Relay & Isolation Logic Replaced ‎ (← links)
  • 05000277/LER-1984-005-01, :on 840323,partial Actuation of Primary Containment Isolation Sys Occurred.Caused by Power Loss to Portion of Primary Containment Isolation Sys Due to Blown Fuse from Shorted Coil in Relay 1GA-K56 ‎ (← links)
  • 05000277/LER-1978-050-03, /03L-0 on 781221:during Routine Surveillance Test, Time to Reach Rated V & Hz for E2 Diesel Was 11 Seconds, & 13 Seconds for E3 Diesel.Probably Due to Faulty Woodward Governor ‎ (← links)
  • 05000277/LER-1991-030, :on 910827,two Diesel Generators Discovered Inoperable Concurrently as Result of Generator Rectifier Ground.Cause Unknown.Appropriate Operating Procedures Reviewed & Revised ‎ (← links)
  • 05000277/LER-1991-029, :on 910824,half Scram Occurred When B RPS Motor Generator Set Output Breaker Tripped.Caused by Broken Wire Inside Rheostat & Less than Adequate Rheostat Installation.Rheostat Replaced ‎ (← links)
  • 05000277/LER-1983-024-01, /01T-0:on 831024,during Audit of Certain Radiographs of Class I Piping,Three Radiographs Read Improperly.Caused by Personnel Error.All Radiographs Reviewed ‎ (← links)
  • 05000277/LER-1983-022-03, /03L-0:on 830907,recirculation Motor Generator Set Room & Recirculation Motor Generator Set Lube Oil Pump Room Sprinkler Sys Did Not Automatically Actuate.Caused by Coil Failure.Proper Dc Coils Installed ‎ (← links)
  • 05000277/LER-1983-021-03, /03L-0:on 830907,during Surveillance Testing of Diesel Generator E-3,operators Noted That Output Power Swinging & Exhaust Temp High.Caused by Failed Elliott Turbocharger & Excess Fuel Igniting Exhaust ‎ (← links)
  • 05000277/LER-1984-003, :on 840131,operator Failed to Take Corrective Action Rapidly Enough to Contain Reactor Coolant Temp, Allowing Heatup Rate to Reach 120 F.Caused by Personnel Error.Operator Disciplined ‎ (← links)
  • 05000277/LER-1983-027-03, /03L-0:on 831215,main Steam Line Temp Element TE-4913D Found to Read Low.Caused by Temp Element Out of Duct W/Retaining Bracket Bent & One Mounting Screw Broken. Temp Element Reinstalled ‎ (← links)
  • 05000277/LER-1983-028-03, /03L-0:on 831223,while Performing Surveillance Testing,Hpsw Pump 2B Declared Inoperable Due to Low Flow. Caused by Internal Wear to Valve Disc Pin & Arm.Parts Replaced ‎ (← links)
  • 05000277/LER-1994-009-01, :on 940921,six Valves Associated W/Primary Containment Isolation Sys Group II Isolation Logic Closed. Caused by Lifting Common Neutral Lead on Relay 16A-K63 Part of PM Activity.Pcis Valves Replaced.W/Undated Ltr ‎ (← links)
  • 05000277/LER-1991-020, :on 910607,two Diesel Generators Discovered Inoperable Due to Mispositioned Valve.Caused by Personnel Error.Valve Immediately Restored & Involved Operator & Chemist Counseled ‎ (← links)
  • 05000277/LER-1991-017, :on 910521,discovered HPCI Sys Unknowingly Rendered Inoperable During Performance of Surveillance Test. Caused by Procedural Inadequacy,Inadequate Design Review & Subsequent Sys Reviews.Mod Initiated ‎ (← links)
  • 05000277/LER-1991-016, :on 910517,mode Switches Placed in Startup Mode W/Reactor Water Level Instrument Perturbation Surveillance Tests Out of Surveillance.Caused by Programmatic Weaknesses in Tests.Surveillance Tests Will Be Revised ‎ (← links)
  • 05000277/LER-1991-011-01, :on 910508,discovered That ST 16.2.1, Fire Sys Weekly Check Inadvertently Deferred Beyond TS Time Limit. Caused by Misleading Test Frequency Listed on Test.Test Revised & Event Reviewed W/Personnel ‎ (← links)
  • 05000277/LER-1983-014-03, /03L-0:on 830812,control Room Fire Barrier Discovered W/O Fire Damper in One Ventilation Duct Penetration.Caused by Damper Not Incorporated Into Original Ventilation Sys Installation.New Damper on Order ‎ (← links)
  • 05000277/LER-1994-010-02, :on 941024,setpoint Drift Associated W/Main Steam Relief Valves & Safety Valves Occurred.Caused by Small Drift in Setpoint of Valves.Refurbished Valves Properly Setup at Test Facility & Installed ‎ (← links)
  • 05000277/LER-1991-024, :on 910630,APRM Surveillance Test Missed. Caused by Personnel Error.Plant Procedures & Tests Revised & Task Force Evaluating Issue of Surveillances ‎ (← links)
  • 05000277/LER-1983-020-03, /03L-0:on 830629,during Visual Investigation of Penetration Fire Barriers,Inadequacies Found in Penetration Seals in Control Room.Caused by Const or Design Error. Temporary Sealing Followed by Seal Upgrade in Progress ‎ (← links)
  • 05000277/LER-1983-016-03, Isolation Valve SV2671C in One Sample Line to Drywell Oxygen Analyzers Failed to Fully Close.Caused by Bent Stem in Isolation Valve.Valve Disassembled & Damaged Parts Replaced ‎ (← links)
  • 05000277/LER-1983-017-03, /03L-0:on 830620,offsite Electrical Source Taken Out of Svc Due to Defective Transformer Relief Device.Relief Device Replaced & Electrical Sys Returned to Normal Configuration ‎ (← links)
  • 05000277/LER-1991-018, :on 910523,Tech Spec 3.0.C Entered & Plant Shutdown Initiated Due to Belief That Diesel Generators Inoperable.Caused by Misclassification of EDG Day Tank. Engineering Review Performed ‎ (← links)
  • 05000277/LER-1991-012-01, :on 910514,discovered That Primary Containment Isolation Valve on Units TIP Sys Purge Lines Not Being Leak Tested.Caused by Inadequate Review of TIP Sys Purge Piping. Procedure Revised to Allow Testing Downstream ‎ (← links)
  • 05000277/LER-1991-015, :on 910515,reactor Bldg & Refueling Floor Ventilation Sys Tripped & Standby Gas Treatment Sys Initiated When Incorrect Fuse Pulled.Caused by Personnel Error.Fuses Will Be Labeled ‎ (← links)
  • 05000277/LER-1991-014, :on 910521,isolation of HPCI Sys Occurred Unexpectedly During Surveillance Test.Caused by Leaking Isolation Valve,Resulting in Pressurization of Switch.Valve Replaced & Test Performed Satisfactorily ‎ (← links)
  • 05000277/LER-1991-013-01, :on 910530,determined That Two Penetration Fire Seals Not Qualifiable Per 10CFR50,App R Due to Voids & Uncured Polyurethane Sealant Matl.Caused by Improper Seal Installation.Firewatches Initiated ‎ (← links)
  • 05000277/LER-1990-004, :on 900321,determined That Under DBA Conditions Some ECCS & RCIC Sys Room Coolers Would Not Receive Min Acceptable Emergency Svc Water Flow.Caused by Buildup of Corrosion Products.Piping Inspected ‎ (← links)
  • 05000277/LER-1983-018-03, /03L-0:on 830624,while Performing HPCI Sys Logic Functional Surveillance Test,Hpci Turbine Control Valve Failed to Open.Caused by Burned Out Dropping Resistor in Power Supply to Woodward Emergency Generator Motor ‎ (← links)
  • 05000277/LER-1983-019-03, /03L-0:on 830626,during Surveillance Testing, Standby Gas Treatment Filter Train Outlet Valve AO-20475-2 Failed to Open.Caused by Binding in Solenoid Valve Mfg by Asco.Solenoid Replaced & Valve Returned to Svc ‎ (← links)
  • 05000277/LER-1983-015-03, /03L-0:on 830611,while Performing Surveillance Test,Reactor Water Cleanup Inboard Isolation Valve MO-2-12-15 Failed to Close.Caused by Open Auxiliary Contact in Motor Control Ctr,Preventing Close Signal.Contact Freed ‎ (← links)
  • 05000277/LER-1983-013-03, /03L-0:on 830503,fluctuating Readings Observed on Iodine Monitor & Downscale Reading Found on Gas Monitor. Caused by Poor Connections in Drywell Air Sampling Radiation Detector Circuitry Due to Oxidation Buildup on Connector ‎ (← links)
  • 05000277/LER-1994-008-02, :on 940909,discovered That ECCS & EDG May Have Been TS Inoperable on 940803 When ESW Outlet Valve MO-0498 Closed & Left Unattended,Causing ECT to Overflow.Valve Opened & ECT Level Restored to Normal Range.W/Undated Ltr ‎ (← links)
  • 05000277/LER-1991-019, :on 910603,primary Containment Isolation Valve Discovered Not Performing Required Tech Spec.Caused by Personnel Error.Task Analysis Performed for Operations Positions Identifying Problems ‎ (← links)
  • 05000277/LER-1983-008-03, /03L-0:on 830407,HPCI High Steam Flow Isolation Switch DPIS-2-23-77 Setpoint Found Above Tech Spec Limit. Caused by Setpoint Drift of Barton Model 288.Instrument Recalibr,Tested & Returned to Svc ‎ (← links)
  • 05000277/LER-1983-009-03, /03L-0:on 830324,during Surveillance Testing,Smoke Detector in Drywell Failed to Provide Audible Alarm Code or Annunciate in Control Room.Caused by Defective Detector Circuit Board.Board Replaced,Tested & Returned to Svc ‎ (← links)
  • 05000277/LER-1983-007-03, /03L-0:on 830404,narrow Range Torus Level Transmitter Lt 8027A Determined to Be Out of Calibr.Caused by Instrument Drift.Instrument Recalibr & Returned to Svc ‎ (← links)
  • 05000277/LER-1991-010-01, :on 910426,recirculation Pump Speed Increase Resulted in Increase in Recirculation Loop Temp from 143 F to 251 F.Caused by Failure to Follow procedure.Single-loop Procedure Will Be Reviewed & Revised ‎ (← links)
  • 05000277/LER-1983-005-03, /03L-0:on 830313,low Flow Alarm on Plant Stack Radiation Monitor Annunciated.Caused by Broken Pump Drive Belt.Belt Replaced ‎ (← links)
  • 05000277/LER-1983-006-01, /01T-0:on 830323,investigation of Spike on Torus Level Recorder Determined That Test Apparatus Left in Svc from 830320 W/Instrument Drain Valve Left Open Providing Potential Containment Leak Path.Caused by Personnel Error ‎ (← links)
  • 05000277/LER-1991-008-01, :on 910407,Tech Spec Violation Due to Failure to Perform Reactor Coolant Temp Logging.Caused by Failure to Follow Procedures.Shift Teams Reviewed & Involved Shift Team Discussed Event in Detail ‎ (← links)
  • 05000277/LER-1994-007-02, :on 940810,secondary Containment Breached to Fight Fire Inside Unit 2 Vent Stack Protective Siding.Caused by Work Area Not Being Properly Staged.Fire Promptly Extinguished & Secondary Containment Restored ‎ (← links)
  • 05000277/LER-1994-006-02, :on 940804,no Firewatches Were in Areas During 50 Minute Period When Carbon Dioxide Fire Suppression Sys Was Inoperable.Caused by Inadequate Communication.Involved Individual Has Been Counselled ‎ (← links)
  • 05000277/LER-1994-005-02, :on 940722,actual Torus Water Level Less than That Indicated on Narrow Range Instrumentation.Initial Ref Marking Used to Support Calibr Activities Not Correct ‎ (← links)
  • 05000277/LER-1994-004-01, :on 940718,HPCI System Was Declared Inoperable. Caused by Problem W/Hpci Signal Isolator.Signal Isolating Device XS-2-23-144 Removed & Replaced ‎ (← links)
  • 05000277/LER-1982-033-03, /03L-0:on 821007,smoke Detector S85 in Torus Room Failed to Calibr to within Specified Limits.Caused by Faulty Smoke Detector,Pyrotronics Model F-5B.Detector Replaced,Unit Calibr & Returned to Svc ‎ (← links)
  • 05000277/LER-1983-012-01, /01P:on 830511,insp of Fire Barrier Penetrations Revealed Inadequacies in Penetration Seals.Caused by Const or Design Error & Inadequate Initial Insp.Fire Watches Posted & Addl Insps Initiated ‎ (← links)
  • 05000277/LER-1982-042-03, /03L-0:on 821210,while Performing Snubber Surveillance Test,Feedwater Snubber & HPCI Exhaust Line Snubber Discovered Detached.Caused by Improper Installation. Snubbers Properly Reinstalled ‎ (← links)
  • 05000277/LER-1991-007, :on 910221,RHR Mo Inboard Isolation Valve MO-2-10-25B Closed on Isolation Signal.Caused by Specified Blocking Permit Less than Adequate.Permit Writers Directed to Walkdown Permits ‎ (← links)
  • 05000277/LER-1991-006-01, :on 910220,scram Caused by de-energizing Intermediate Range Monitor.Caused by Failure to Follow Procedure.Individuals Involved Counseled on Requirements to Perform Safety Related Blocking Reviews ‎ (← links)
  • 05000277/LER-1991-005-01, :on 910212,primary Containment Isolation Sys Actuated Due to Blown Fuse During Removal of Blocking Permit Caused by Ground Created While Performing Mod Installation Work.Shift Permit Enforced ‎ (← links)
  • 05000277/LER-1991-004-01, :on 910202,emergency Svc Water Pump B Received Unexpected Automatic Start Signal.Caused by Use of Wrong Control Switch to Close Pump Breaker During Surveillance.Procedure Revised ‎ (← links)
  • 05000277/LER-1994-002, :on 940421,determined That Sample Lines on Systems Became Plugged Due to Build Up of Silt from River Water.Sample Lines Were Flush & Systems Were Returned to Service ‎ (← links)
  • 05000277/LER-1982-032-03, /03L-0:on 821114,during Surveillance Test,No Air Flowed from B Main Control Room Emergency Ventilation Fan. Caused by Fan Damper Controller Being Out of Adjustment. Controller Adjusted,Sys Tested & Returned to Svc ‎ (← links)
  • 05000277/LER-1982-038-03, /03L-0:on 821106 & 08,isolation Valves SV2671C, SV2671D & SV2671A in Sample Lines to Oxygen Analyzers Failed to Fully Close.Caused by Accumulation of Dirt on Seat & Valve Disk.Valves Disassembled,Cleaned & Rebuilt ‎ (← links)
  • 05000277/LER-1991-001-03, :on 910118,HPCI Sys Potentially Inoperable. Caused by Inadequate EQ Review of Components in Hpic Room. Walkdown of Units 2 & 3 Hpic Rooms Will Be Performed to Ensure EQ Has Been Evaluated ‎ (← links)
  • 05000277/LER-1994-003-01, :on 940515,Unit 2 Scram on High Neutron Flux Condition Occurred Due to Unexpected Speed Increase on 2A Recirc Pump.Restored & Reset PCIS & RPS Scram Logics ‎ (← links)
  • 05000277/LER-1994-002-03, :on 940426,confirmed That Circulating Water Intake Composite Sampler Sys Not Properly Functioning.Caused by Small Valve on Sys That Became Plugged.Composite Sample Valve & Line Flushed ‎ (← links)
  • 05000277/LER-1983-003-03, /03L-0:on 830206,coolant Leak Discovered in Cooling Sys of Diesel Driven Fire Pump.Caused by Leaking Water Pump Shaft Seal.Replacement Pump Placed in Svc on 830209 ‎ (← links)
  • 05000277/LER-1990-034, :on 901112,discovered That Emergency Diesel Generator Droop Selector Switches in Parallel Position. Caused by Personnel Error.Personnel Involved Counseled on Importance of Attention to Detail ‎ (← links)
  • 05000277/LER-1982-034-03, /03L-0:on 821013,two Ventilation Duct Fire Dampers Failed to Operate Properly.Caused by Loose Mounting Screw on One Coil & Displaced Piece of Electrical Insulation on Other.Both Mechanisms Realigned & Tested ‎ (← links)
  • 05000277/LER-1991-002-02, :on 910121,RHR Sys Shutdown Cooling Isolation Occurred When Sys Blocking Permit for ADS Applied During Refueling Outage.Caused by Poor Drawing Legibility.Drawing Enhanced & Blocking Permit Rewritten ‎ (← links)
  • 05000277/LER-1991-003-01, :on 910121,primary Containment Isolation Sys Group III Outboard Isolation & Standby Gas Treatment Sys Initiated,Resulting in Reactor Pressure Sys Bus Trip.Caused by Undervoltage Condition ‎ (← links)
  • 05000277/LER-1982-037-03, /03L-0:on 821012,control Rod Drive Area Smoke Detector Circuit Set Off False Alarm.Caused by Stripped Terminal Screw in Auto Code Box & Loose Connection from Circuitry.Screw Replaced & Connection Tightened ‎ (← links)
  • 05000277/LER-1982-035-01, /01P:on 821021,diesel Generator Bldg Cardox Tank Pressure Found at 20 Psig Below Tech Spec Limit of 280 Psig. Caused by Tank Not Being Pressurized Correctly During Recent Filling Operation.Tank Pressurized within 16-h ‎ (← links)
  • 05000277/LER-1990-008, :on 900414,testing of LPCI Pumps & Core Spray Subsystems Not Performed,Per Tech Spec 4.5.A.4.Caused by Personnel Error in Not Recognizing Inoperable Status of RHR Pump 2D When Changing to Refuel Mode ‎ (← links)
  • 05000277/LER-1990-003-01, :on 900310,primary Containment Leakage Rate Limit Exceeded Tech Spec Requirements Due to Excessive Through Seat Leakage on Main Steam Line Drain Isolation Valves MO-74 & MO-77 ‎ (← links)
  • 05000277/LER-1990-036, :on 901115,excessive Reactor Coolant Cooldown Occurred While Placing Shutdown Cooling Mode of RHR in Svc. Caused by Incorrect Procedural Guidance.Appropriate Operating Procedures Will Be Revised ‎ (← links)
  • 05000277/LER-1990-037, :on 901119,discovered That TS Violation Occurred as Result of Not Taking Appropriate LCO Actions When IRM Channels for RPS a Trip Circuit Fell Below Required Amount.Caused by Procedural Weakness ‎ (← links)
  • 05000277/LER-1990-035, :on 901115,discovered That Multiple Safety Sys Could Be Inoperable as Result of 4 Kv Emergency Bus Undervoltage Relays Outside Acceptable Calibr Limits.Caused by Inadequate Design.Relays Modified ‎ (← links)
  • 05000277/LER-1982-029-03, /03L-0:on 820915,during Power,Supervisory Alarm Occurred Indicating Fire Sys Problems.Investigation Revealed Heat Detectors in Startup Switchgear Bldg Inoperable.Caused by Disconnected Circuit Breaker Due to Stripped Screw ‎ (← links)
  • 05000277/LER-1990-033, :on 901108,Tech Spec Limiting Condition of Operation Not Entered for Inoperable Ci Valve ‎ (← links)
  • 05000277/LER-1990-032, :on 901106,potential Loss of Primary Containment Occurred ‎ (← links)
  • 05000277/LER-1990-031, :on 890314,missed Core Spray Surveillance Resulted in TS Violation Due to Inadequate Controls ‎ (← links)
  • 05000277/LER-1990-030, :on 901024,control Room Emergency Ventilation Actuation Occurred Due to Inadvertent Opening of 480 Volt Breaker ‎ (← links)
  • 05000277/LER-1982-025-03, /03L-0:on 820827,while Performing Surveillance Test,C RHR Pump Room C Cooling Fan Would Not Start in Automatic.Caused by Corroded Contacts on C Fan Switch DPS 0400-16.Switch Rewired & Calibr ‎ (← links)
  • 05000277/LER-1982-026-03, /03L-0:on 820831,RHR Pump 2A Failed to Start During Test on FR-2-10-143.Caused by Uncharged Breaker Closing Spring Due to Faulty Closing Latch Monitoring Switch in Charging Motor Circuitry.Switch Replaced ‎ (← links)
  • 05000277/LER-1982-027-01, /01T-0:on 820910,svc Air Valve to Containment Found Open.Caused by Personnel Failure to Make Entry in Locked Valve Log Book When Valves Opened.Valve Closed & Locked ‎ (← links)
  • 05000277/LER-1982-028-03, /03L-0:on 820908,LIS-2-3-73B,reactor Lo-Lo-Lo Containment Spray Interlock Discovered Out of Calibr. Caused by Setpoint Drift of Rosemont Model 1151 Trip Unit. Device Recalibr ‎ (← links)
  • 05000277/LER-1990-028, :on 900801,discovered Missed Surveillance on Drywell Suppression Chamber Vacuum Breaker ‎ (← links)
  • 05000277/LER-1993-013-01, :on 930819,TS Violation Occurred When Primary Containment Isolation Sys Inoperable & Isolation Valve Not Isolated & Logged.Caused by Insufficient Trouble Shooting. Auxiliary Contact Replaced ‎ (← links)
  • 05000277/LER-1982-017-03, /03L-0:on 820825,diesel Overspeed Trip Alarm Sounded.Caused by Shorted Overspeed Trip Switch Due to Water Entering Switch Via Cracked Switch Housing.Switch & Valve Replaced ‎ (← links)
  • 05000277/LER-1982-024-03, /03L-0:on 820827,pump Trip Annunicator Did Not Clear After Core Spray Surveillance Test.Caused by Misaligned Driving Pawl in 2D Core Spray Pump Motor Breaker Charging Spring.Pawl Realigned & Interlocks Reset ‎ (← links)
  • 05000277/LER-1982-023-03, /03L-0:on 820908,reactor Core Isolation Cooling Governor Found W/Positive Ground During Routine Surveillance Test.Caused by Burned Out Resistor on Woodward Electric Governor Magnetic Servo.Resistor Replaced ‎ (← links)
  • 05000277/LER-1982-045-03, /03L-0:on 821230,while Performing Routine Decontamination of RHR Pump Room 2B,motor Found Wet to Extent Considered Inoperable.Caused by Personnel Error. Supervisor Reinstructed Vendor in Proper Method ‎ (← links)
  • 05000277/LER-1982-021-03, /03L-0:on 820620,combined Leakage for Type B & C Tests Exceeded 0.6 La.Caused by Failure of MSIV Due to Improper Seat Contact Resulting from Damaged Seats,Plugs & Guides.Valves Repaired & Tested ‎ (← links)
  • 05000277/LER-1980-030-01, /01T-0:on 801124,needle Valve in Air Supply to Boot Seal of Inboard Isolation Valve AO-2511 Found Closed. Caused by Damage During Const Work.Valve Reopened & Full Boot Seal Pressure Restored ‎ (← links)
  • 05000277/LER-1979-027, /O3L-0 on 790521:reactor Water Cleanup Inboard Isolation Valve Failed to Automatically Isolate in Test. Caused by Misaligned Limit Switch on Valve.Switch Adjusted & Maint Procedure Strengthened ‎ (← links)
  • 05000277/LER-1979-029, /O3L-0 on 790524:firewatch Patrol Was Not Conducted While Fire Detection Sys Was Out of Svc for Const. Caused by Failure in Communications.Procedures Changed ‎ (← links)
  • 05000277/LER-1982-039-03, /03L-0:on 821126,HPCI Flow Controller Read Approx 80% Instead of 100%.Caused by Faulty Amplifier Card in Flow Controller.Flow Controller Replaced & HPCI Sys Tested & Returned to Svc ‎ (← links)
  • 05000277/LER-1982-041-01, /01T-0:on 821210,reactor Water Cleanup High Temp Isolation Signal Bypassed After Trip.Caused by False Initiation Signal Due to Short Circuit in Temp Switch Caused by Frayed Wire ‎ (← links)
  • 05000277/LER-1978-036-03, /03L-0 on 780901:failure of Auxiliary Oil Pump to Start Due to a Ground in Motor.Motor,Baldor Type 1040D, 7 1/2 H.P.,25OV.D.C. Was Replaced & HPCI Sys Tested Satisfactorily W/In 36 Hours.Ads Timers Not W/In Tech Specs ‎ (← links)
  • 05000277/LER-1978-037-03, /03L-0 on 780901:while Testing ADS Subsys,Timers on Both Loops Were Found Outside the 115-125 Second Limit of Tech Specs Due to Setpoint Drift of Time Delay Relays. Timers Were Calibrated,Retested & Returned to Svc ‎ (← links)
  • 05000277/LER-1990-020, :on 900821,discovered That Battery Charger 2D Inoperable for Undervoltage Alarm Relay Calibr.Caused by Personnel Error.Event Reviewed by Mgt W/Shift Supervisor ‎ (← links)
  • 05000277/LER-1982-031-03, /03L-0:on 820831,smoke Detector S14 in Emergency Switchgear Room B Failed to Calibr to Tech Spec Limits. Caused by Faulty Smoke Detector.Detector Replaced ‎ (← links)
  • 05000277/LER-1982-020-03, /03L-0:on 820806,drywell Pressure Recorders PR-2508A & PR-2508B Failed Downscale Due to Blown Fuses. Caused by Intentional Ground on Positive Side of Transmitters.Mod to Eliminate Ground Completed on 820811 ‎ (← links)
  • 05000277/LER-1982-018-31, /03L-0:on 820724,while Testing Smoke Detectors in Cable Spreading Room,One Fire Damper Remained Open When Trip Was Initiated.Caused by Improperly Set Solenoid Release Mechanism (Derby Electric Release).Mechanism Reset & Test ‎ (← links)
  • 05000277/LER-1994-001-01, :on 940119,TS Violation Occurred Due to Fire Detection Sys Breaker Open W/No Hourly Firewatch in DG Cardox Room.Closed Breaker & Restored Fire Detection Instrumentation ‎ (← links)
  • 05000277/LER-1982-019-03, /03L-0:on 820725,main Steam Line Radiation Monitors a & C Revealed hi-hi Trip Setpoints Greater than Tech Spec Limit.Caused by Instrument Zero Drift.Monitors Recalibr ‎ (← links)
  • 05000277/LER-1993-016-01, :on 931221,HPCIS Declared Inoperable During Performance of Surveillance Test.Cause Not Yet Determined. Instument Caibration Line Flushed to Clear Blockage & Back Filled.Procedures Revised ‎ (← links)
  • 05000277/LER-1993-015-01, :on 931201,TS Violation Occurred Due to Improperly Secured Main Stack Particulate Filter.Filters Changed & Gas Marnelli Samples Obtained to Identify & Quantify Nuclides in Main Stack Effluent ‎ (← links)
  • 05000277/LER-1981-002-01, /01T-0:on 810105,reactor Core Isolation Cooling Pump Flow Indication Failed Rendering Automatic Flow Control Sys Inoperable.Caused by Electronic Failure of Square Root Extractor in Flow Control Circuitry.Extractor Replaced ‎ (← links)
  • 05000277/LER-1980-035-03, /03L-0:on 801218,stand by Gas Treatment Sys Manual Reset Cutout Switch TS 00013A Would Not Reset.Caused by Broken Diatemp Model 106K Manual Reset Switch.Switch Replaced w/auto-reset Type Switch ‎ (← links)
  • 05000277/LER-1980-036-03, /03L-0:on 801217,HPCI Turbine Steam Supply High Flow Sensor Setpoint Found Greater than Tech Spec Limit. Caused by Setpoint Drift on Barton Model 288 Differential Pressure Switch.Instrument Recalibr ‎ (← links)
  • 05000277/LER-1980-034-03, /03L-0:on 801210,A RHR Pump Room Coolers Failed to Start Automatically.Caused by Improper Adjustment of Cell Switch on RHR Pump Breaker,Ge Type 4.16-250-84.Breaker Replaced & Satisfactory Surveillance Test Performed ‎ (← links)
  • 05000277/LER-1980-015-03, /03X-1:on 800904,during Surveillance Testing at Full Power,Reactor Core Isolation Cooling Outboard Steam Supply Isolation Valve MO-2-13-16 Failed to Close.Caused by Improperly Functioning Switch on Limitorque Operator ‎ (← links)
• ML24081A121 (redirect page) ‎ (← links)
  • IR 05000277/2024002 ‎ (← links)
  • ML24227A549 ‎ (← links)
  • ML24081A118 ‎ (← links)
• 05000277/LER-2024-003, Automatic Reactor Scram Following Main Turbine Trip Due to Degraded Condenser Vacuum ‎ (← links)
• 05000277/LER-2024-002, Uncoordinated DC Circuits Cause Unanalyzed Condition ‎ (← links)