ML17339B119

Proposed Amend to Facility OLs DPR-31 & DPR-41,Delta T Vs Reactor Power Shift Check,Turkey Point Units 3 & 4, Informal Rept

ML17339B119
Person / Time
Site:	Turkey Point
Issue date:	05/31/1980
From:	Udy A EG&G, INC.
To:	Shemanski P Office of Nuclear Reactor Regulation
References
CON-FIN-A-6256 EGG-EA-5154, NUDOCS 8006200047
Download: ML17339B119 (12)

Text

ATTACHMENT TO LOSURE EGG-EA-5154 May 1980 PROPOSED AMENDMENT TO FACILITY OPERATING LICENSES DPR-31 AND DPR-41, AT VERSUS REACTOR POWER SHIFT CHECK, TURKEY POINT, UNIT NOS.3 AND 4, DOCKET NOS.50-250 AND 50-251, TAC NO.6541 A.C.Udy U.S.Department of Energy Idaho Operations Office~Idaho National Engineering Laboratory

~,'~m;~~a~~a~~~~w~l1 cA l'., h This is an informal report intended for use as a preliminary or working document Prepared f or the U.S.Nuclear Regulatory Commission

'Under DOE Contract No.DE-AC07-76ID01570 FIN No.A6256~~EHZGr'idaho n

lt++EAR&Idaho.Inc.FOAM KGKG408 IAev, 11 79I INTERIM REPORT Accession No.Report No.EGG-EA-5154 Contract Program or Project Title: Electrical, Instrumentation and Control System Support Subject of this Document: 'Proposed Amendment to Facility Operating Licenses DPR-31 and DRP-41, AT Ve sus Reactor Power Shift Check, Turkey Point Unit los.3 and 4, Docket Nos.50-250 and 50-251, TAC No.6541 Type of Document: Informal Report Author(s):

A.C.Udy Date of Document: May 1980 Responsible NRC Individual and NRC Office or Division: Paul C.Shemanski, Division of Operating Reactors This document was prepared primarily for preliminary or internal use.It has not received full review and approval.Since there may be substantive changes, this document should not be considered final.EGB G Idaho, Inc.Idaho Falls, Idaho 83415 Prepared for the U.S.Nuclear Regulatory Commission Washington, O.C.Under OOE Contract No.DE-AC07-76ID01570 NRC FIN No.A6256 INTERIM REPORT 1647F TECHNICAL EVALUATION REPORT PROPOSED AMENDMENT TO FACILITY OPERATING LICENSES DPR-31 AND DPR-41 5T VERSUS REACTOR POWER SHIFT CHECK TURKEY POINT, UNIT NOS~3 AND 4 Docket Nos.50-250 and 50-251 TAC No.6541 May 1980 A.'.Udy Reliability and Statistics Branch Engineering Analysis Division EG&G Idaho, Inc.

ABSTRACT Florida Power 6.Light Company has requested approval of an alternate method for the shift check of the Nuclear Power Range Instrument channe's.This report examines the currently approved method and the proposed method of performing this shift check.Either method is satisfactory for providing the shift check.FIN No.A6256 EICS Support CONTENTS

1.0 INTRODUCTION

~~~~~~~~2.0 EVALUATION OF THE TURKEY POINT STATION, UNITS 3 AND 4 2.1 Review Guidelines

~t~~~~~~~~~~~~~~~~1 2.2 Shift Check Procedures

~~~~~~~~~~~~~2 2.3 Shift Check Evaluation

~~~~~~~~3 3~0 S UliRY~~~~~~~~o~~~~0~~~~~~~~~~~~~~~3

4.0 REFERENCES

~~~,~~~~~4 111 I

TECHNICAL EVALUATION REPORT PROPOSED AMENDMENT TO FACILITY OPERATING LICENSES DPR-31 AND DPR-41 dT VERSUS REACTOR POWER SHIFT CHECK TURKEY POINT, UNIT NOS~3 AND 4

1.0 INTRODUCTION

On January 25, 1977 , Florida Power&Light Co.(FPL)requested to 1 amend Appendix A of their Facility Operating Licenses DPR-31 and DPR-41~These licenses are for the Turkey Point Station, Units 3 and 4, respec-tively.The change is to allow a"dT versus reactor power curve" or optionally, for convenience, the already approved method,"load versus flux curve." FPL letters of March 20, 1980 , and May 1, 1980 , provided addi-2 3 tional information for this review.Additional information is from the Unit Final Safety Analysis Report{FSAR).2.0 EVALUATION OF THE TURKEY POINT STATION, UNITS 3 AND 4 2.1 Review Guidelines.

The intent of this evaluation is to determine if the following guidelines are satisfied by either the original method or the proposed method of performing the shift check, in keeping with the basis and testing requirements of IEEE Standard 338 4.1.Guideline No.1-The method should minimize the effort and time required to perform checks, functional tests, and calibration verification.

2.Guideline No.2-The testing should provide trend data and the capability to observe degradation and the onset of incipient failures.3.Guideline No.3-Testing should be conducted per writ-ten test procedures.

4.Guideline No.4-The instrument check can be conducted by comparing readings with different variables that bear a known relationship to one another.Additionally, the unit FSAR requires, in Section 7.4.4C: 5.Guideline No.5-The total error from drif t in the power range channels should be less than+1.0Z of full power.2.2 Shift Check Procedures.

Table 4.1-1 of the unit Technical Speci-fication requires, at a minimum, the power range channels be checked by the Load Versus Flux curve once per eight-hour shift.This check compares the 1 generator load and back pressure to reactor power.This comparison xs 2 done by reading the variables on a graph, as part of Operating Proced-ure 12304.3.This provides a shift correction factor to be used when the power range channels are read.No calibration adjustments are made as a result of this check.Secondary inefficiencies (that is, opening heater bypasses, temperature change in cooling water, inaccuracies in backpressure readings, etc.)may require large correction factors to derive the correct power level" using this method.As ammended, Operating Procedure 12304.3 would allow use of either a 3 5T versus power shift check or the load versus flux curve shift check.The 5T versus power method derives a shift correction factor for the power range channels from a graph, and is dependent on the difference between the hot leg and cold leg temperatures.

FPL has determined that the 5T versus power method is accurate to within+0.7Z, while the original flux versus 3 load method is accurate to within+1.0Z.1 Either method of the channel check is only to detect gross failures (that is, blown fuses, defective instruments, etc.).-The requirement for daily calibration of the power range channels is not changed by the proposed change in shift check procedures.

FPL is committed to perform both the flux 3 versus load and the 5T versus reactor power methods initially, to , 2 acquaint plant personnel with the new method before it is used independently.

2.3 Shift Check Evaluation.

Guideline 1 would minimize the effort and time required to perform this channel check.Since secondary ineffici-encies are not involved, the dT versus reactor power method is viewed as meeting this guideline.

Allowing the use of cithez method allows for pos-sible failure of the instrumentation needed for one method of the channel check, and using the other method while repairs are made.Guideline 2 requires that the testing pxovide trend data to observe degradation or onset of incipient failure.Either method of channel check satisfies this guideline.

Guideline 3 requires written test pxocedures.

FPL has provided a marked-up copy of Opex'ating Procedure 12304.3 which allows either method of shift check.This is adequate, as precedures are normally changed after approval to change the method is received.Guideline 4 allows an instrument check by comparing readings of dif-ferent variables as long as a known relationship exists.This guideline is satisfied foz either method of the power range channel check.Guideline 5 requires that the total drift in the power range channels be less than+1.0X of full power.FPL has shown that the proposed 5T vezsus reactor power range channel check is conducive to meeting this requirement, and is more accurate than the original flux versus load method.3.0 SVMHARY FPL requested approval of an alternate method to provide the shift check of the nuclear power range instrument channels.The material submitted by FPL identifies Operating Pxocedure 12304.3 for both methods of the shift check of the power range channels.FPL has shown that the accumulative errors induced by eithez method will result in

~~'the total drift of the power range channels of less than+1.0X of full~-scale.The NRC should allow the use of either method.

4.0 REFERENCES

1.FPL letter, Robert E.Uhrig, to Director of Nuclear Reactor Regulation,"Proposed Amendment to Facility Operating Licenses DPR-31 and DPR-41," January 25, 1977, L-77-32.2.FPL letter, Robert E.Uhrig, to Office of Nuclear Reactor Regulation,"'5T Versus Reactor Power'urve," March 20, 1980, L-80-93.3.FPL letter, Robe.t E.Uhrig, to Office of Nuclear Reactor Regulation,"'5T Versus Reactor Power'urve," Nay 1, 1980, L-80-134.4.IEEE Standard 338-1975,"IEEE Standard Criteria for the Periodic Test-ing of Nuclear Power Generating Station Class 1E Power and Protection Systems," Nuclear Power Fngineering Committee of the IEEE Power Engin-eering Society, Institute of Electrical and Electronic Engineers, 1975.

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