ML17349A339

LER 92-008-00:on 920723,discovered That Analog Channel Operational Test for Overpressure Mitigation Sys Did Not Check & Adjust Setpoint,Per TS 4.4.9.3.1.Caused by Inadequate Procedure.Procedures revised.W/920814 Ltr

ML17349A339
Person / Time
Site:	Turkey Point
Issue date:	08/24/1992
From:	Knorr J, Plunkett T FLORIDA POWER & LIGHT CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
L-92-226, LER-92-008, LER-92-8, NUDOCS 9208240031
Download: ML17349A339 (5)

Text

ACCELERATED DI RIBVTION DEMONS+ATION SYSTEM REGULAT Y INFORMATION DISTR I BUT ION SYSTEl"l (R I DB)ACCESSION hfBR: 9208240031 DQC.DATE:'2/08/24 NOTARIZED:

NQ FACIL: 50-250 Turkey Point Planti Unit 3i Florida Power and Light C AUTH.NANE AUTHOR AFFILIATION KNORRi J.E.Florida Power 5 Light Co.PLUNKETT T.F.Florida Power 5: Light Co.REC TP.N*NE RECIPIENT AFFILIATION DOCKET¹05000250

SUBJECT:

LER 92-008-00:

on 920723'iscovered that analog channel operational test for overpressure mitf gation sos did not check 5 adJust setpointi per TS 4.4.9.3.1.Caused b j inadequate procedure.

Procedures revised.N/920814 ltr.DISTRIBUTION CODE: IE22T COPIES RECEIVED: LTR ENCL SIZE: TITLE: 50.73/50.9 Licensee Event Report (LER>i Incident Rp ti etc.NOTES: NRR RAGHAVANi L 05000280 A-REC IP I ENT ID CODE/NAf iE PD2-2 LA AULUCKz R COP IES LTTR ENCL 1 1 REC IP IENT ID CODE/NAf'IE PD2-2 PD COP IFS LTTR ENCL 1 1 INTERNAL: ACNll AEOD/DBP/TPAI3 NRR/DET/Eh!EB 7E NRR./DL.PG/LP EB10 NRR/DRFP/PRPB1 1 NRR/DST/SICBSH3 NRR/DST/BRXB GE REB/DSIR/FIB 2 1 2 1 1 1 1 AEOD/DOA AEOD/POAB/DSP NRR/DLP G/LHFB 10 NRR/DQEA/QEAB NRR/DST/SELB 8D RRCB~LBSD1 REG FT 02 RGN2 F ILE 01 1 2 1 1 EXTERNAL.:

EGLcG BPYCEi J.H NPC PDR NBIC POORER M.2 1 1 L ST LOBBY 4!ARD NSIC f'!URPHYj G.A NUDOC S FULL.T XT NOTE TO ALL"RIDS RECIPIENTS PLEASE HELP US TO REDUCE WASTE!CONTACT THE DOCUMENT CONTROL DESK.ROOM Pl-37 (EXT.504-2065)TO ELIMINATE YOUR NAME FROM DISTRIBUTION

.LISTS FOR DOCUMENTS YOU DON'T NEED!FUL.L TEXT CGfdVFRS ION REQUIRED TOTAL I'JUi~iHER QF COP IEB REGUIRFD: LTTR 30 ENCL 30 C

~'.O.Box 029100, miami, FL, 33102-9100 i~'lAo",<L-92-226 10 CFR 50.73 U.S.Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C.20555 Gentlemen:

Re: Turkey Point Units 3 and 4 Docket Nos.50-250 and 50-251 Reportable Event: 92-008-00 Analog Channel Operational Test for Overpressure Mitigation System Not in Accordance with Technical S ecifications The attached Licensee Event Report 250-92-008-00 is being provided in accordance with 10 CFR 50.73 (a)(2)(i)(B).If there are any questions please contact us.Very truly yours, T.F.Plunkett Vice President Turkey Point Nuclear TFP/JEK/jk enclosure cc: Stewart D.Ebneter, Regional Administrator, Region II, USNRC Ross C.Butcher, Senior Resident Inspector, USNRC, Turkey Point Plant Q J tjgprp+~Qgn4QQ3i 9~Q PDR ADQCK Q PDP S gp LICENSEE EVENT REPORT (LER)FACILITY NAME (1)TURKEY POINT UNITS 3 AND 4 DOCKET NUMBER (2)05000250 PAGE (3)QF 3 Analog Channel Operational Test for Overpressure Mitigation System Not in Accordance with Technical Specifications.

EVENT DATE (5)LER NUMBER (6)RPT DATE (7)OTHER FACILITIES INV.(8)MON DA Y YR SEQ 0 DA Y NAME DOCKET g (S)07 23 92 92 008 00 08 24 92 OPERATING HODE (2)POJCR LCYO.00)87 10 CFR 50.73 a 2 i B LICENSEE CONTACT FOR THIS LER (12)James E.Knorr, Regulation and Compliance Specialist COHPLETE ONE LINE FOR EACH COHPONENT FAILURE DESCRIBED IN THIS REPORT (13)TELEPHONE NUMBER 305-246-6757 CAUS E SYSTEH COHPONEN T HANUFACTUR ER NPRDS CAUSE SYSTEM COHPONEN T HANUFACTURER NPRDS SUPPLEMENTAL REPORT EXPECTED (14)(f.f yes, cmnplete EXPECTED SUBMISSION DATE)NO EXPECTED SUBHISSI ON DATE (13)MONTH DAY YEAR ABSTRACT (16)On July 23, 1992,'during a procedure review, Turkey Point personnel discovered an Analog Channel Operational Test procedure deficiency.

Technical Specification 4.4.9.3.1 requires an Analog Channel Operational Test of the Overpressure Mitigating System.This test requirement includes adjustments as necessary of alarms interlocks and/or trip setpoints.

The method used at-the time of discovery actuated a circuit which caused the pressurizer power operated relief valve to open.The procedure injected a simulated setpoint signal but did not check and adjust as necessary the set point for the Overpressure Mitigating System as required by the Technical Specifications.

The cause of the deficiency was an inadequate procedure.

The procedures for both Units 3 and 4 have been revised.

LZCBEEBEI+BET REPORT (LBR)TEXT CO~ATZOE FACILITY NAME TURKEY POINT UNIT 3)lee DOCKET NUMBER LER NUMBER PAGE NO.05000250 92-008-00 02 oF 03 I.DESCRIPTION OF THE EVENT On July 23, 1992, 3-0SP-041.4,"Overpressure Mitigating System Nitrogen Backup Leak and Functional Test," was reviewed to prepare for the upcoming outage.During the review, operations personnel identified that the procedure performed a functional test as required by Technical Specifications in affect prior to August 28, 1991.Technical Specifications in affect since August 28, 1991, require an Analog Channel Operational Test (ACOT).The definition for an ACOT includes"the injection of a simulated signal into the channel as close to the sensor as practicable to verify the operability of alarm, interlock and/or trip functions.

The analog channel operational test shall include adjustments, as necessary, of the alarm, interlock and/or trip setpoints such that, the setpoints are within the required range and accuracy." The ACOT is required by Technical Specification to be done within 31 days prior to entering a condition in which the PORV (power operated relief valve)(EIIS-JC, Component-RV) is required to be operable and at least once per 31 days thereafter when the PORV is required to be operable.Contrary to the Technical Specification definition, testing done on the Overpressure Mitigating System (OMS)'(EIIS-JC, Component-PA) only provided a zero voltage signal to one side of the pressure comparator circuit which artificially reduces the setpoint of the comparator to zero psig.The comparator is designed to send an open signal to the pressurizer PORVs when the system pressure is greater than the setpoint pressure based upon an OMS setpoint of 415 psig+15 psig.The 415 psig setpoint is designed to be in affect at all times when OMS is activated and the Reactor Coolant System temperature is below 285'F.Since during the functional test the setpoint is artificially reduced to 0 psig, the alarm and trip setpoint have only been verified during calibration which is required by Technical Specifications each 18 months.The following dates are those during which the respective units were taken to a temperature of less than 285'F and therefore by procedure required the operability of the OMS: Unit 3-April 29, 1992 to May 11, 1992 Unit 4-January 28, 1992 to February 4, 1992-December 11, 1991 to December 17, 1991 For each of these cooldowns and for the heatup following the, dual unit outage in September and October of 1991 for Unit 3 and 4 respectively the OMS was placed in service using the inadequate functional test procedure.

II.CAUSE OF THE EVENT The root cause of the inadequate Analog.Channel Operational Test was an inadequate procedure.

Procedures in place, which controlled the functional test did not provide for the test of the setpoints and adjustment as appropriate.

FACILITY NAME TURKEY POINT UNIT 3)I XCBNSBETBNT RBBORT (LBR)TBZT CONOBTZON DOCKET NUMBER LER NUMBER PAGE NO.05000250 92-008-00 03 oF 03 III.ANALYSIS OF THE EVENT Unit 3 and Unit 4 have PORVs which protect the reactor coolant system from overpressurization at reduced temperature.

The Technical Specifications require the OMS to be operable any time the temperature is less than 275'F.To ensure operability, the Technical Specifications require an Analog Channel Operational Test.Initiation of the open signal to the PORVs comes from a pressure comparator which receives two signals;actual pressure from a pressure transmitter PT 403, and a signal which at a temperature less than 285'F is a constant 415 psig+15 psig.Procedure 3/4-0SP-041.4,"Overpressure Mitigating System Nitrogen Backup Leak and Functional Test," was used to verify the functionality of the circuitry in opening the PORV but did not verify the setpoint of 415 psig for actuation.

The test reduced the setpoint to essentially zero.Therefore any pressure input resulted in the opening of the PORV.Calibrations of the Unit 3 and Unit 4 channels had last been performed prior to the startups of the units during the Fall 1991.Each calibration has provided assurance that the setpoint is in the Technical Specification required range.The last time a calibration was completed on OMS for each unit was prior to startup following the dual unit outage in 1991.A review of the past few years of calibration as found data revealed that the channels would have been considered operable during an Analog Channel Operational Test if the test had checked the setpoints.

Therefore there is a high degree of confidence that the setpoints have been at levels required by Technical Specifications.

IV.CORRECTIVE ACTIONS 1.Procedures, 3/4-0SP-041.4 were revised to incorporate analog channel operational tests on July 28, 1992.2.Other Technical Specification required Analog Channel Operational Test procedures are being reviewed to ensure that each test will be completed in accordance with the ACOT definition.

V.ADDITIONAL INFORMATION None.