Information Notice 1985-49, Relay Calibration Problem

Relay Calibration Problem

ML031180261
Person / Time
Site:	Beaver Valley, Millstone, Hatch, Monticello, Calvert Cliffs, Dresden, Davis Besse, Peach Bottom, Browns Ferry, Salem, Oconee, Mcguire, 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, 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, 05000000, Zimmer, Fort Saint Vrain, Shoreham, Satsop, Trojan, Atlantic Nuclear Power Plant, Skagit, Marble Hill, Crane
Issue date:	07/01/1985
From:	Jordan E L NRC/IE
To:
References
IN-85-049, NUDOCS 8506260654
Download: ML031180261 (3)

SSINS NO.: 6835IN 85-49UNITED STATESNUCLEAR REGULATORY COMMISSIONOFFICE OF INSPECTION AND ENFORCEMENTWASHINGTON, D.C. 20555July 1, 1985IE INFORMATION NOTICE NO: 85-49: RELAY CALIBRATION PROBLEM

Addressees

All nuclear power reactor facilities holding an operating license (OL) or aconstruction permit (CP).

Purpose

This information notice provides information on a potentially significantproblem pertaining to relay orientation during calibration and operation. Itis expected that recipients will review the information for applicability totheir facilities and consider actions, if appropriate, to preclude a similarproblem occurring at their facilities. However, suggestions contained in thisinformation notice do not constitute NRC requirements; therefore, no specificaction or written response is required.Discussion:South Carolina Electric and Gas Company, at the Summer nuclear power plant,recently discovered that there was a significant error in the calibration ofseveral E-7000 series Agastat time-delay relays. The licensee's procedure forreplacement of Agastat timing relays did not require calibration of theserelays in the installed position. During relay replacement, these time-delayrelays were "bench" calibrated in a horizontal position, then field mounted ina vertical orientation. Subsequent time-delay measurements determined that thedelay times of the installed devices were as much as 30% greater than thatestablished during "bench" calibration.Licensee investigation of this anomaly determined that the manufacturer's datasheet for installation and operation of these relays identifies a potential forthe observed calibration error. This data sheet states that a dial calibrationerror may result if the device is mounted horizontally without the manufacturer'ssupplied horizontal operation options. Because these relays were mountedvertically at this facility, the potential for error as a result of horizontal"bench" calibration was overlooked. Because of this oversight, the licensee'srelay replacement procedure did not specify device orientation during calibration.Several of these relays were functionally arrayed (sequentially or in parallel)in safety-related applications, such as in the emergency diesel generator under-voltage start circuitry. The above identified time-delay error went undetectedfor a period of approximately 4 months for some of these relays. This occurredbecause the licensee's replacement procedure specified only an operational orfunctional postmaintenance test of the system containing the relays. This methodof testing did not detect the individual relay time-delay calibration errors.8506260654 I- ,IN 85-49July 1, 1985 The licensee has subsequently revised their relay calibration procedures tocalibrate or check the calibration of relays after mounting in place, wherepractical. The procedures were also revised to ensure "bench" calibrationsare performed in the same orientation as mounted, where applicable. Personnelinvolved in relay calibration have received training on the revised procedures.No specific action or written response is required by this information notice.If you have any questions about this matter, please contact the RegionalAdministrator of the appropriate NRC Regional Office or this office.44a DirectorDivisio f Emergency Preparednessand Engineering ResponseOffice of Inspection and Enforcement

Technical Contact:

H. Bailey, IE(301) 492-9006Attachment: List of Recently Issued IE Information Notices

Attachment 1IN 85-49July 1, 1985LIST OF RECENTLY ISSUEDIE INFORMATION NOTICESInformation Date ofNotice No. Subject Issue Issued to85-4885-4785-4685-4585-4485-4385-4285-41Respirator Users Notice:Defective Self-ContainedBreathing Apparatus AirCylindersPotential Effect Of Line-Induced Vibration On CertainTarget Rock Solenoid-OperatedValvesClarification Of SeveralAspects Of Removable Radio-active Surface ContaminationLimits For Transport Packages6/19/856/18/856/10/85Potential Seismic Interaction 6/6/85Involving The Movable In-CoreFlux Mapping System Used InWestinghouse Designed PlantsAll power reactorfacilities holdingan OL or CP, research,and test reactor,fuel cycle andPriority 1 materiallicenseesAll power reactorfacilities holdingan OL or CPAll power reactorfacilities holdingan OLAll power reactorfacilities holdingan OL or CPAll power reactorfacilities holdingan OLAll power reactorfacilities holdingan OL or CPAll power reactorfacilities holdingan OL or CPAll power reactorfacilities holdinga CPEmergency CommunicationSystem Monthly TestRadiography Events At PowerReactorsLoose Phosphor In Panasonic800 Series Badge Thermo-luminescent Dosimeter (TLD)ElementsScheduling Of Pre-LicensingEmergency PreparednessExercises5/30/855/30/855/29/855/24/85OL = Operating LicenseCP = Construction Permit