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| {{#Wiki_filter:UNITED STATESNUCLEAR REGULATORY COMMISSIONOFFICE OF NUCLEAR REACTOR REGULATIONWASHINGTON, D.C. 20555December 21, 1993NRC INFORMATION NOTICE 93-99: UNDERVOLTAGE RELAY AND THERMAL OVERLOADSETPOINT PROBLEMS | | {{#Wiki_filter:UNITED STATESNUCLEAR REGULATORY COMMISSIONOFFICE OF NUCLEAR REACTOR REGULATIONWASHINGTON, D.C. 20555December 21, 1993NRC INFORMATION NOTICE 93-99: UNDERVOLTAGE RELAY AND THERMAL OVERLOADSETPOINT PROBLEMS |
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| ==Purpose== | | ==Purpose== |
| The U.S. Nuclear Regulatory Commission (NRC) is issuing this informationnotice to alert addressees to continuing discoveries of undervoltage relay andthermal overload setpoints that are set too low. It is expected thatrecipients will review the information for applicability to their facilitiesand consider actions, as appropriate, to avoid similar problems. However,suggestions contained in this Information notice are not NRC requirements;therefore, no specific action or written response is required.BackgroundIn August 1976, the NRC wrote generic letters to all LWR licensees regardingthe need for licensees to evaluate any generic implications of several eventsat the Millstone site involving episodes of sustained degraded grid voltage.On June 2, 1977, as part of multiplant action MPA-23, the staff stated itsposition that all licensees must have a second level of undervoltageprotection with a time delay. (During degraded grid voltage episodes,undervoltage relays and thermal overload protective relays protect the safetyequipment.) In a generic letter dated August 8, 1979, the NRC requested alllicensees to determine the capability of the offsite power system to operateall required loads within their voltage ratings under all conditions withintheir design basis. The licensees reviewed their undervoltage relay setpointson each of these occasions. In 1981, the NRC issued Branch TechnicalPosition, Power System Branch-1, "Adequacy of Station Electric DistributionSystem Voltages," which discussed, among other things, the addition of asecond undervoltage relay with an associated time delay. Between 1981 and1992, the NRC issued two information notices, in which it discussedundervoltage relay setpoints and other concerns:1. IN 84-02, "Operating a Nuclear Power Plant at VoltageLevels Lower than Analyzed," issued January 10, 1984.2. IN 91-29, "Deficiencies Identified During Electrical DistributionSystem Functional Inspections," issued April 15, 1991.9312150073 PDR E No4tEC 93-0 1e ' , t IN 93-99December 21, 1993 . IN 91-29, Supplement 1, TDeficiencies Identified During | | The U.S. Nuclear Regulatory Commission (NRC) is issuing this informationnotice to alert addressees to continuing discoveries of undervoltage relay andthermal overload setpoints that are set too low. It is expected thatrecipients will review the information for applicability to their facilitiesand consider actions, as appropriate, to avoid similar problems. However,suggestions contained in this Information notice are not NRC requirements;therefore, no specific action or written response is required.BackgroundIn August 1976, the NRC wrote generic letters to all LWR licensees regardingthe need for licensees to evaluate any generic implications of several eventsat the Millstone site involving episodes of sustained degraded grid voltage.On June 2, 1977, as part of multiplant action MPA-23, the staff stated itsposition that all licensees must have a second level of undervoltageprotection with a time delay. (During degraded grid voltage episodes,undervoltage relays and thermal overload protective relays protect the safetyequipment.) In a generic letter dated August 8, 1979, the NRC requested alllicensees to determine the capability of the offsite power system to operateall required loads within their voltage ratings under all conditions withintheir design basis. The licensees reviewed their undervoltage relay setpointson each of these occasions. In 1981, the NRC issued Branch TechnicalPosition, Power System Branch-1, "Adequacy of Station Electric DistributionSystem Voltages," which discussed, among other things, the addition of asecond undervoltage relay with an associated time delay. Between 1981 and1992, the NRC issued two information notices, in which it discussedundervoltage relay setpoints and other concerns:1. IN 84-02, "Operating a Nuclear Power Plant at VoltageLevels Lower than Analyzed," issued January 10, 1984.2. IN 91-29, "Deficiencies Identified During Electrical DistributionSystem Functional Inspections," issued April 15, 1991.9312150073 PDR E No4tEC 93-0 1e ' , t IN 93-99December 21, 1993 . IN 91-29, Supplement 1, TDeficiencies Identified During |
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| --"VIN 93-99December 21, 1993 This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.Bran K. rimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contact:C. Morris, NRR(301) 504-2778 | | --"VIN 93-99December 21, 1993 This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.Bran K. rimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contact:C. Morris, NRR(301) 504-2778 |
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| ===Attachments:=== | | ===Attachments:=== |
| 1. Representative List of UndervoltageRelay Setpoint Revisions 1988-19932. List of Recently Issued NRC Information NoticesE plion:The stress laid by the initial reviewer on thelicensees and the staff should feel for such apreblem, viz. low UVR set points, has been allpresent IN.degree of concern thatwidespread and persistentbut eliminated from the(SEE PREVIOUS CONC.)*C.MORRIS15 NOV. 93(S/D)*SEE PREVIOUS CONCURRENCES*DO RS/OGCB | | 1. Representative List of UndervoltageRelay Setpoint Revisions 1988-19932. List of Recently Issued NRC Information NoticesE plion:The stress laid by the initial reviewer on thelicensees and the staff should feel for such apreblem, viz. low UVR set points, has been allpresent IN.degree of concern thatwidespread and persistentbut eliminated from the(SEE PREVIOUS CONC.)*C.MORRIS15 NOV. 93(S/D)*SEE PREVIOUS CONCURRENCES*DO RS/OGCB |
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| * C/OGCB:DORS:NRR D/DORS:NRRNCampbell GHMarcus07/30/93 08/10/9312//$193*EELB:DE:NRRCMorris04/28/93*SC/EELB:DE:NRREWWeiss95/19/93*C/EELB:DE:NRRCHBerlinger05/19/93*D/DE: NRRJTWiggins07/23/93*RPB:ADMTech Ed07/13/93# Concurred in electronically by JMain.DOC NAME: 93-99.IN IN 93-XXNovember XX, 993This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.Brian K. Grimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contact:C. Morris, NRR(301) 504-2778 | | * C/OGCB:DORS:NRR D/DORS:NRRNCampbell GHMarcus07/30/93 08/10/9312//$193*EELB:DE:NRRCMorris04/28/93*SC/EELB:DE:NRREWWeiss95/19/93*C/EELB:DE:NRRCHBerlinger05/19/93*D/DE: NRRJTWiggins07/23/93*RPB:ADMTech Ed07/13/93# Concurred in electronically by JMain.DOC NAME: 93-99.IN IN 93-XXNovember XX, 993This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.Brian K. Grimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contact:C. Morris, NRR(301) 504-2778 |
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Undervoltage Relay & Thermal Overload Setpoint ProblemsML031060586 |
Person / Time |
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Site: |
Beaver Valley, Millstone, Hatch, Monticello, Calvert Cliffs, Dresden, Davis Besse, Peach Bottom, Browns Ferry, Salem, Oconee, Nine Mile Point, Palisades, Palo Verde, Perry, Indian Point, Fermi, Kewaunee, Catawba, Harris, Wolf Creek, Saint Lucie, Point Beach, Oyster Creek, Watts Bar, Hope Creek, Grand Gulf, Cooper, Sequoyah, Byron, Pilgrim, Arkansas Nuclear, Three Mile Island, Braidwood, Susquehanna, Summer, Prairie Island, Columbia, Seabrook, Brunswick, Surry, Limerick, North Anna, Turkey Point, River Bend, Vermont Yankee, Crystal River, Haddam Neck, Ginna, Diablo Canyon, Callaway, Vogtle, Waterford, Duane Arnold, Farley, Robinson, Clinton, South Texas, San Onofre, Cook, Comanche Peak, Yankee Rowe, Maine Yankee, Quad Cities, Humboldt Bay, La Crosse, Big Rock Point, Rancho Seco, Zion, Midland, Bellefonte, Fort Calhoun, FitzPatrick, McGuire, LaSalle, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant |
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Issue date: |
12/21/1993 |
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From: |
Grimes B K Office of Nuclear Reactor Regulation |
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To: |
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References |
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IN-93-099, NUDOCS 9312150073 |
Download: ML031060586 (12) |
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Similar Documents at Beaver Valley, Millstone, Hatch, Monticello, Calvert Cliffs, Dresden, Davis Besse, Peach Bottom, Browns Ferry, Salem, Oconee, Nine Mile Point, Palisades, Palo Verde, Perry, Indian Point, Fermi, Kewaunee, Catawba, Harris, Wolf Creek, Saint Lucie, Point Beach, Oyster Creek, Watts Bar, Hope Creek, Grand Gulf, Cooper, Sequoyah, Byron, Pilgrim, Arkansas Nuclear, Three Mile Island, Braidwood, Susquehanna, Summer, Prairie Island, Columbia, Seabrook, Brunswick, Surry, Limerick, North Anna, Turkey Point, River Bend, Vermont Yankee, Crystal River, Haddam Neck, Ginna, Diablo Canyon, Callaway, Vogtle, Waterford, Duane Arnold, Farley, Robinson, Clinton, South Texas, San Onofre, Cook, Comanche Peak, Yankee Rowe, Maine Yankee, Quad Cities, Humboldt Bay, La Crosse, Big Rock Point, Rancho Seco, Zion, Midland, Bellefonte, Fort Calhoun, FitzPatrick, McGuire, LaSalle, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant |
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Category:NRC Information Notice
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Mclaughlin on NRC, Regarding NRC Information Notice 2006-13: Groundwater Contamination2006-07-13013 July 2006 E-mail from M. Mclaughlin on NRC, Regarding NRC Information Notice 2006-13: Groundwater Contamination 2020-09-03 The following query condition could not be considered due to this wiki's restrictions on query size or depth: <code> [[:Beaver Valley]] OR [[:Millstone]] OR [[:Hatch]] OR [[:Monticello]] OR [[:Calvert Cliffs]] OR [[:Dresden]] OR [[:Davis Besse]] OR [[:Peach Bottom]] OR [[:Browns Ferry]] OR [[:Salem]] OR [[:Oconee]] OR [[:Nine Mile Point]] OR [[:Palisades]] OR [[:Palo Verde]] OR [[:Perry]] OR [[:Indian Point]] OR [[:Fermi]] OR [[:Kewaunee]] OR [[:Catawba]] OR [[:Harris]] OR [[:Wolf Creek]] OR [[:Saint Lucie]] OR [[:Point Beach]] OR [[:Oyster Creek]] OR [[:Watts Bar]] OR [[:Hope Creek]] OR [[:Grand Gulf]] OR [[:Cooper]] OR [[:Sequoyah]] OR [[:Byron]] OR [[:Pilgrim]] OR [[:Arkansas Nuclear]] OR [[:Three Mile Island]] OR [[:Braidwood]] OR [[:Susquehanna]] OR [[:Summer]] OR [[:Prairie Island]] OR [[:Columbia]] OR [[:Seabrook]] OR [[:Brunswick]] OR [[:Surry]] OR [[:Limerick]] OR [[:North Anna]] OR [[:Turkey Point]] OR [[:River Bend]] OR [[:Vermont Yankee]] OR [[:Crystal River]] OR [[:Haddam Neck]] OR [[:Ginna]] OR [[:Diablo Canyon]] OR [[:Callaway]] OR [[:Vogtle]] OR [[:Waterford]] OR [[:Duane Arnold]] OR [[:Farley]] OR [[:Robinson]] OR [[:Clinton]] OR [[:South Texas]] OR [[:San Onofre]] OR [[:Cook]] OR [[:Comanche Peak]] OR [[:Yankee Rowe]] OR [[:Maine Yankee]] OR [[:Quad Cities]] OR [[:Humboldt Bay]] OR [[:La Crosse]] OR [[:Big Rock Point]] OR [[:Rancho Seco]] OR [[:Zion]] OR [[:Midland]] OR [[:Bellefonte]] OR [[:Fort Calhoun]] OR [[:FitzPatrick]] OR [[:McGuire]] OR [[:LaSalle]] OR [[:Fort Saint Vrain]] OR [[:Shoreham]] OR [[:Satsop]] OR [[:Trojan]] OR [[:Atlantic Nuclear Power Plant]] </code>.
[Table view]The following query condition could not be considered due to this wiki's restrictions on query size or depth: <code> [[:Beaver Valley]] OR [[:Millstone]] OR [[:Hatch]] OR [[:Monticello]] OR [[:Calvert Cliffs]] OR [[:Dresden]] OR [[:Davis Besse]] OR [[:Peach Bottom]] OR [[:Browns Ferry]] OR [[:Salem]] OR [[:Oconee]] OR [[:Nine Mile Point]] OR [[:Palisades]] OR [[:Palo Verde]] OR [[:Perry]] OR [[:Indian Point]] OR [[:Fermi]] OR [[:Kewaunee]] OR [[:Catawba]] OR [[:Harris]] OR [[:Wolf Creek]] OR [[:Saint Lucie]] OR [[:Point Beach]] OR [[:Oyster Creek]] OR [[:Watts Bar]] OR [[:Hope Creek]] OR [[:Grand Gulf]] OR [[:Cooper]] OR [[:Sequoyah]] OR [[:Byron]] OR [[:Pilgrim]] OR [[:Arkansas Nuclear]] OR [[:Three Mile Island]] OR [[:Braidwood]] OR [[:Susquehanna]] OR [[:Summer]] OR [[:Prairie Island]] OR [[:Columbia]] OR [[:Seabrook]] OR [[:Brunswick]] OR [[:Surry]] OR [[:Limerick]] OR [[:North Anna]] OR [[:Turkey Point]] OR [[:River Bend]] OR [[:Vermont Yankee]] OR [[:Crystal River]] OR [[:Haddam Neck]] OR [[:Ginna]] OR [[:Diablo Canyon]] OR [[:Callaway]] OR [[:Vogtle]] OR [[:Waterford]] OR [[:Duane Arnold]] OR [[:Farley]] OR [[:Robinson]] OR [[:Clinton]] OR [[:South Texas]] OR [[:San Onofre]] OR [[:Cook]] OR [[:Comanche Peak]] OR [[:Yankee Rowe]] OR [[:Maine Yankee]] OR [[:Quad Cities]] OR [[:Humboldt Bay]] OR [[:La Crosse]] OR [[:Big Rock Point]] OR [[:Rancho Seco]] OR [[:Zion]] OR [[:Midland]] OR [[:Bellefonte]] OR [[:Fort Calhoun]] OR [[:FitzPatrick]] OR [[:McGuire]] OR [[:LaSalle]] OR [[:Fort Saint Vrain]] OR [[:Shoreham]] OR [[:Satsop]] OR [[:Trojan]] OR [[:Atlantic Nuclear Power Plant]] </code>. |
UNITED STATESNUCLEAR REGULATORY COMMISSIONOFFICE OF NUCLEAR REACTOR REGULATIONWASHINGTON, D.C. 20555December 21, 1993NRC INFORMATION NOTICE 93-99: UNDERVOLTAGE RELAY AND THERMAL OVERLOADSETPOINT PROBLEMS
Addressees
All holders of operating licenses or construction permits for nuclear powerplants.
Purpose
The U.S. Nuclear Regulatory Commission (NRC) is issuing this informationnotice to alert addressees to continuing discoveries of undervoltage relay andthermal overload setpoints that are set too low. It is expected thatrecipients will review the information for applicability to their facilitiesand consider actions, as appropriate, to avoid similar problems. However,suggestions contained in this Information notice are not NRC requirements;therefore, no specific action or written response is required.BackgroundIn August 1976, the NRC wrote generic letters to all LWR licensees regardingthe need for licensees to evaluate any generic implications of several eventsat the Millstone site involving episodes of sustained degraded grid voltage.On June 2, 1977, as part of multiplant action MPA-23, the staff stated itsposition that all licensees must have a second level of undervoltageprotection with a time delay. (During degraded grid voltage episodes,undervoltage relays and thermal overload protective relays protect the safetyequipment.) In a generic letter dated August 8, 1979, the NRC requested alllicensees to determine the capability of the offsite power system to operateall required loads within their voltage ratings under all conditions withintheir design basis. The licensees reviewed their undervoltage relay setpointson each of these occasions. In 1981, the NRC issued Branch TechnicalPosition, Power System Branch-1, "Adequacy of Station Electric DistributionSystem Voltages," which discussed, among other things, the addition of asecond undervoltage relay with an associated time delay. Between 1981 and1992, the NRC issued two information notices, in which it discussedundervoltage relay setpoints and other concerns:1. IN 84-02, "Operating a Nuclear Power Plant at VoltageLevels Lower than Analyzed," issued January 10, 1984.2. IN 91-29, "Deficiencies Identified During Electrical DistributionSystem Functional Inspections," issued April 15, 1991.9312150073 PDR E No4tEC 93-0 1e ' , t IN 93-99December 21, 1993 . IN 91-29, Supplement 1, TDeficiencies Identified During
--"VIN 93-99December 21, 1993 This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.Bran K. rimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contact:C. Morris, NRR(301) 504-2778
Attachments:
1. Representative List of UndervoltageRelay Setpoint Revisions 1988-19932. List of Recently Issued NRC Information Notices Attachment 1IN 93-99December 21, 993Representative List of Undervoltaqe Relay Set Point Revision Notifications andTechnical Specification Change Proposals for 1988-1993Event NotificationNumberLicenseeEvent Notification Date113741404300000147801654017121PilgrimPilgrimPilgrim111January 30, 1988November 18, 1988June 30, 1988151Cooper 1Crystal River 3Robinson 2February 17,September 8,November 16,1989198919895111832218466188921902320021Oconee 1, 2 and 3McGuire 1 and 2St. Lucie 2Haddam Neck 1Calvert Cliff 1 and 2Ft. CalhounKewaunee 1Salem 2Dresden 2 and 3Dresden 2Zion 1 and 2April 24, 1990May 14, 1990July 14, 1990August 2, 1990December 6, 1990February 12, 1991February 20, 1991February 27, 1991August 23, 1991November 20, 1991December 19, 199151251204352050320542216912228122498152515225802265822847 (TOL)22918231482319123338233652338523439 (TOL)23452235762378423932000002422924384Indian Point 3Dresden 3Washington Nuclear 2Washington Nuclear 2Vermont YankeeQuad Cities 1 and 2LaSalle 1 and 2LaSalle 2Crystal River 3Grand GulfComanche Peak 2Crystal River 3Zion 1 and 2Byron 1 and 2CallawayCrystal River 3Dresden 2 and 3January 9, 1992January 22, 1992February 19, 1992March 1, 1992April 1, 1992April 7, 1992April 27, 1992April 29, 1992May 1, 1992May 11, 1992May 13, 1992June 4, 1992July 2, 1992July 24, 1992July 23, 1992September 14, 1992October 6, 1992*TOL -Thermal Overload Attachment 1IN 93-99December 21, 1993 Event Notification Licensee Event Notification Date ClassNumber00000 Prairie Island 1 & 2 November 6, 1992 100000 St. Lucie 1 November 30, 1992 124757 Maine Yankee December 15, 1992 500000 Diablo Canyon 1 and 2 December 22, 1992 124845 Point Beach 1 and 2 January 7, 1993 125248 (TOL) Pilgrim March 29, 1993 525362 South Texas April 6, 1993 5Events Notification Number-00000 Licensees whose undervoltage relay setpointnotifications to the NRC were reported by LERs, licensee letter, etc., andevent notification numbers if any, were not known.Class Definitions:1. Undervoltage Relay setpoints were found to be incorrect because ofdesign errors.2. Undervoltage Relay setpoints, as found, were not the same as required bythe technical specification.3. Safety load circuit breaker thermal overloads or other trip setpointswere too low because of design errors.4. Safety load circuit breaker thermal overload, or other trip setpoints,as found, were not the same as required by the technical specification.5. Membership in one of the preceding four classes could not be definitelyestablished because of incomplete information in the event notificatio Att~ehment 2IN 93-99December 21, 993LIST OF RECENTLY ISSUEDNRC INFORMATION NOTICESInformation Date ofNotice No. Subject Issuance Issued to93-9893-9793-9693-9593-9493-93Motor Brakes on ValveActuator MotorsFailures of YokesInstalled on WalworthGate and Globe ValvesImproper Reset CausesEmergency DieselGenerator FailuresStorm-Related Loss ofOffsite Power Eventsdue to Salt Buildupon Switchyard InsulatorsUnauthorized ForcedEntry into the Pro-tected Area at ThreeMile Island Unit 1 onFebruary 7, 1993Inadequate Control ofReactor Coolant SystemConditions During ShutdownPlant Improvements toMitigate Common Depend-encies in ComponentCooling Water SystemsInadequate QualityAssurance Program ofVendor SupplyingSafety-Related Equipment12/20/9312/17/9312/14/9312/13/9312/09/9312/08/9312/07/9312/07/93All holders of OLs and CPsfor nuclear power reactors.All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor nuclear power reactorslocated close to a largebody of salt water.All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor nuclear power reactors.All holders of OLs or CPsfor nuclear power reactorsand all recipients ofNUREG-0040, 'License Con-tractor and Vendor Inspec-tion Status ReportR (WhiteBook)..93-9291-21,Supp. 1OL -Operating LicenseCP = Construction Permit IN 93-99December 21, 1993 This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.Odginal signed byBrian K. GrimesBrian K. Grimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contact:C. Morris, NRR(301) 504-2778
Attachments:
1. Representative List of UndervoltageRelay Setpoint Revisions 1988-19932. List of Recently Issued NRC Information NoticesE plion:The stress laid by the initial reviewer on thelicensees and the staff should feel for such apreblem, viz. low UVR set points, has been allpresent IN.degree of concern thatwidespread and persistentbut eliminated from the(SEE PREVIOUS CONC.)*C.MORRIS15 NOV. 93(S/D)*SEE PREVIOUS CONCURRENCES*DO RS/OGCB
- C/OGCB:DORS:NRR D/DORS:NRRNCampbell GHMarcus07/30/93 08/10/9312//$193*EELB:DE:NRRCMorris04/28/93*SC/EELB:DE:NRREWWeiss95/19/93*C/EELB:DE:NRRCHBerlinger05/19/93*D/DE: NRRJTWiggins07/23/93*RPB:ADMTech Ed07/13/93# Concurred in electronically by JMain.DOC NAME: 93-99.IN IN 93-XXNovember XX, 993This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.Brian K. Grimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contact:C. Morris, NRR(301) 504-2778
Attachments:
1. Representative List of UndervoltageRelay Setpoint Revisions 1988-19932. List of Recently Issued NRC Information NoticesException:The stress laid by the initial reviewer on the degree of concern thatlicensees and the staff should feel for such a widespread and persistentproblem, viz. low UVR set points, has been all but eliminated from thepresent IN. G4'C.MORRIS15 NOV. 93Document Name: G:\SHARED\R3UNRELS.IN*SEE PREVIOUS CONCURRENCES# Concurred in electronically byD/DORS:NRR *C/OGCB: DORS:NRRBKGrimes GHMarcus11/ /93 A 08/10/93*C/EELB:DE:NRR *D/DE:NRRCHBerlinger JTWiggins05/19/93 07/23/93JMain.*OGCB:DORS:NRRNCampbell07/30/93*RPB:ADMTech Ed07/13/93*EELB:DE:NRRCMorris04/28/93*SC/EELB:DE:NRREWWeiss05/19/93&Wp: & 4 Lso1 IN 93-XXNovember XX, 1993 This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.Brian K. Grimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contact:C. Morris, NRR(301) 504-2778
Attachments:
1. Representative List of UndervoltageRelay Setpoint Revisions 1988-19932. List of Recently Issued NRC Information NoticesDocument Name:G:\SHARED\R3UNRELS.IN*SEE PREVIOUS CONCURRENCES# Concurred inD/DORS:NRRBKGrimesll/ /93*C/EELB:DE:NRRCHBerlinger05/19/93electronically by*C/OGCB:DWRS:NRRGHMarcus08/10/93*D/DE:NRRJTWiggins07/23/93JMain.*OGCB: DORS:NRRNCampbell07/30/93*RPB:ADMTech Ed07/13/93*EELB:DE:NRRCMorris04/28/93*SC/EELB:DE:NRREWWeiss05/19/93 IN 93-XXAugust XX, 1993 This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.Brian K. Grimes, DirectorDivision of Operating Reactor SupportOffice of Nuclear Reactor RegulationTechnical contact:C. Morris, NRR(301) 504-2778
Attachments:
1. Representative List of UndervoltageRelay Setpoint Revisions 1988-19932. List of Recently Issued NRC Information Notices*SEE PREVIOUS CONCURRENCESDocument Name: UNRELSET.INDORS/OGCBNCampbell07/30/93D/DORS:BKGrime08/ /93C/OGCB: DORS:NRRGHMarcus6#/W08/to /93*EELB:DE:NRRCMorris04/28/93*SC/EELB:DE:NRREWWeiss05/19/93*C/EELB:DE:NRRCHBerlinger05/19/93*D/DE : NRRJTWiggins07/23/93*RPB:ADMTech Ed07/13/93# Concurred in electronically by JMai IN 93-XXAugust XX, 1993 This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.Brian K. Grimes, DirectorDivision of Operational EventsAssessmentOffice of Nuclear Reactor RegulationTechnical contact:C. Morris, NRR(301) 504-2778
Attachments:
1. Representative List of Undervoltage Relay Setpoint Revisions 1988-19932. List of Recently Issued NRC Information Notices*SEE PREVIOUS CONCURRENCESDocument Name: UNRELSET.INDRS/OGCBNCampbell07/8* /93D/DORS:NRRBKGrimes07/ /93C/OGCB:DORS:NRRGHMarcus07/ /93*EELB:DE:NRRCMorris04/28/93*SC/EELB:DE:NRREWWeiss05/19/93*C/EELB:DE:NRRCHBerlinger05/19/93*D/DE:NRRJTWiggins07/23/93*RPB:ADMTech Ed07/13/93# Concurred in electronically by JMai _> K_> IN 93-XXJuly XX, 1993 This information notice requires no specific action or written response. Ifyou have any questions about the information in this notice, please contactthe technical contact listed below or the appropriate Office of NuclearReactor Regulation (NRR) project manager.Brian K. Grimes, DirectorDivision of Operational EventsAssessmentOffice of Nuclear Reactor RegulationTechnical contact:C. Morris, NRR(301) 504-2778
Attachments:
1. Representative List of Undervoltage Relay Setpoint Revisions 1988-19932. List of Recently Issued NRC Information Notices*SEE PREVIOUS CONCURRENCESDocument Name: UNRELSET.INDORS/OGCB DNCampbell BI07/ /93 0,*C/EELB:DE:NRRCHBerlinger05/19/93/DORS:NRRKGrimes7/ /24*EELB:DE:NRRCMorris04/28/93*SC/EELB:DE:NRREWWeiss05/19/93MarcusT/ /93*RPB:ADMTech Ed07/13/93# Concurred in electronically by JMain.
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list | - Information Notice 1993-01, Accuracy of Motor-Operated Valve Diagnostic Equipment Manufactured by Liberty Technologies (4 January 1993)
- Information Notice 1993-02, Malfunction of a Pressurizer Code Safety Valve (4 January 1993, Topic: Loop seal)
- Information Notice 1993-04, Investigation and Reporting of Misadministrations by the Radiation Safety Officer (7 January 1993, Topic: Uranium Hexafluoride, Overexposure)
- Information Notice 1993-05, Locking of Radiography Exposure Devices (14 January 1993, Topic: Uranium Hexafluoride, Inattentive)
- Information Notice 1993-06, Potential Bypass Leakage Paths Around Filters Installed in Ventilation Systems (22 January 1993)
- Information Notice 1993-07, Classification of Transportation Emergencies (1 February 1993, Topic: Uranium Hexafluoride)
- Information Notice 1993-08, Failure of Residual Heat Removal Pump Bearings Due to High Thrust Loading (1 February 1993, Topic: Probabilistic Risk Assessment)
- Information Notice 1993-09, Failure of Undervoltage Trip Attachment on Westinghouse Model DB-50 Reactor Trip Breaker (2 February 1993)
- Information Notice 1993-10, Dose Calibrator Quality Control (2 February 1993, Topic: Uranium Hexafluoride)
- Information Notice 1993-11, Single Failure Vulnerability of Engineered Safety Features Actuation Systems (4 February 1993)
- Information Notice 1993-12, Off-Gassing in Auxiliary Feedwater System Raw Water Sources (11 February 1993)
- Information Notice 1993-13, Undetected Modification of Flow Characteristics in High Pressure Safety Injection System (16 February 1993)
- Information Notice 1993-14, Clarification of 10 CFR 40.22, Small Quantities of Source Material (18 February 1993)
- Information Notice 1993-15, Failure to Verify the Continuity of Shunt Trip Attachment Contacts in Manual Safety Injection and Reactor Trip Switches (18 February 1993)
- Information Notice 1993-16, Failures of Not-Locking Devices in Check Valves (19 February 1993, Topic: Anchor Darling, Flow Induced Vibration)
- Information Notice 1993-17, Safety Systems Response to Loss of Coolant and Loss of Offsite Power (25 March 1994, Topic: Fire Barrier, Backfit)
- Information Notice 1993-18, Portable Moisture-Density Gauge User Responsibilities During Field Operations (10 March 1993, Topic: Moisture Density Gauge, Stolen)
- Information Notice 1993-19, Slab Hopper Bulging (17 March 1993, Topic: Hydrostatic)
- Information Notice 1993-20, Thermal Fatigue Cracking of Feedwater Piping to Steam Generators (24 March 1993, Topic: Thermal fatigue)
- Information Notice 1993-21, Summary of NRC Staff Observations Compiled During Engineering Audits or Inspections of Licensee Erosion/Corrosion Programs (25 March 1993, Topic: Weld Overlay, Thermal fatigue)
- Information Notice 1993-22, Tripping of Klockner-Moeller Molded-Case Circuit Breakers Due to Support Lever Failure (26 March 1993, Topic: Commercial Grade, Thermal fatigue)
- Information Notice 1993-23, Weschler Instruments Model 252 Switchboard Meters (31 March 1993, Topic: Commercial Grade, Thermal fatigue)
- Information Notice 1993-24, Distribution of Revision 7 of NUREG-1021, Operation Licensing Examiner Standards (31 March 1993, Topic: Job Performance Measure, Thermal fatigue)
- Information Notice 1993-25, Electrical Penetration Assembly Degradation (1 April 1993)
- Information Notice 1993-26, Grease Soldification Causes Molded-Case Circuit Breaker Failure to Close (31 January 1994)
- Information Notice 1993-27, Level Instrumentation Inaccuracies Observed During Normal Plant Depressurization (8 April 1993, Topic: Reactor Vessel Water Level)
- Information Notice 1993-28, Failure to Consider Loss of DC Bus in the Emergency Core Cooling System Evaluation May Lead to Nonconservative Analysis (9 April 1993, Topic: Fuel cladding)
- Information Notice 1993-29, Problems with the Use of Unshielded Test Leads in Reactor Protection System Circuitry (12 April 1993)
- Information Notice 1993-30, NRC Requirements for Evaluation of Wipe Test Results; Calibration of Count Rate Survey Instruments (12 April 1993)
- Information Notice 1993-31, Training of Nurses Responsible for the Care of Patients with Brachytherapy Implants (13 April 1993, Topic: Brachytherapy)
- Information Notice 1993-32, Nonconservative Inputs for Boron Dilution Events Analysis (21 April 1993, Topic: Shutdown Margin)
- Information Notice 1993-33, Potential Deficiency of Certain Class Ie Instrumental and Control Cables (28 April 1993)
- Information Notice 1993-33, Potential Deficiency of Certain Class IE Instrumental and Control Cables (28 April 1993, Topic: Brachytherapy)
- Information Notice 1993-34, Potential for Loss of Emergency Cooling Function Due to a Combination of Operational and Post-LOCA Debris in Containment (6 May 1993, Topic: Brachytherapy)
- Information Notice 1993-35, Insights from Common-Cause Failure Events (12 May 1993, Topic: Brachytherapy)
- Information Notice 1993-36, Notifications, Reports, and Records of Misadministrations (7 May 1993, Topic: Brachytherapy)
- Information Notice 1993-37, Eyebolts with Indeterminate Properties Installed in Limitorque Valve Operator Housing Covers (19 May 1993, Topic: Brachytherapy)
- Information Notice 1993-38, Inadequate Testing of Engineered Safety Features Actuation Systems (24 May 1993)
- Information Notice 1993-39, Radiation Beams From Power Reactor Biological Shields (25 May 1993)
- Information Notice 1993-39, Radiation Beams from Power Reactor Biological Shields (25 May 1993)
- Information Notice 1993-40, Fire Endurance Test Results for Thermal Ceramics FP-60 Fire Barrier Material (26 May 1993, Topic: Safe Shutdown, Fire Barrier, Fire Protection Program)
- Information Notice 1993-41, One Hour Fire Endurance Test Results for Thermal Ceramics Kaowool, 3M Company FS-195 and 3M Company Interam E-50 Fire Barrier Systems (28 May 1993, Topic: Safe Shutdown, Fire Barrier)
- Information Notice 1993-42, Failure of Anti-Rotation Keys in Motor-Operated Valves Manufactured by Yelan (9 June 1993)
- Information Notice 1993-43, Use of Inappropriate Lubrication Oils in Satety-Related Applications (10 June 1993, Topic: Commercial Grade)
- Information Notice 1993-44, Operational Challenges During a Dual-Unit Transient (15 June 1993)
- Information Notice 1993-45, Degradation of Shutdown Cooling System Performance (16 June 1993)
- Information Notice 1993-46, Potential Problem with Westinghouse Rod Control System and Inadvertent Withdrawal of Single Rod Control Cluster Assembly (10 June 1993)
- Information Notice 1993-47, Unrecognized Loss of Control Room Annunciators (18 June 1993)
- Information Notice 1993-48, Failure of Turbine-Driven Main Feedwater Pump to Trip Because of Contaminated Oil (6 July 1993, Topic: Water hammer)
- Information Notice 1993-49, Improper Integration of Software Into Operating Practices (8 July 1993)
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