ML20235X361

Summary of 870629-30 Meetings W/Util in Monroeville,Pa Re Audit of Plant Safety Monitoring Sys Verification & Validation Program.List of Attendees & Viewgraphs Encl

ML20235X361
Person / Time
Site:	Vogtle
Issue date:	07/20/1987
From:	Mark Miller Office of Nuclear Reactor Regulation
To:	Office of Nuclear Reactor Regulation
References
NUDOCS 8707240149
Download: ML20235X361 (30)

Text

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.O k ,4#N UNITED STATES -

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NUCLEAR HEGULATORY COMMISSION

WASHINGTON, D. C. 20555 1

2 0 JUL 1987

. Docket No.: 50-424 l

APPLICANT: Georgia Power Company

FACILITY

Vogtle, Unit 1 1

SUMMARY

OF AUDIT OF THE V0GTLE PLANT SAFETY MONITORING SYSTEM VERIFICATION AND VALIDATION PROGRAM On Jur,e 29-30, 1987, the staff met with the licensee and its representatives, at the Westinghouse facilities located in Monroeville, PA to audit the Vogtle Plant Safety Monitoring System (PSMS) Verification and Validation (V8V)

Program. In conducting the audit, the staff was assisted by a consultant from Schar, Inc. Enclosure 1 lists the audit participants. Enclosure 2 identifies the agenda for the audit.

l A representative of Southern Company Services Inc. described the chro-l nology of events in the design of the PSMS. Enclosure 3 identifies these l

events. A member of Westinghouse's staff made a presentation on the design organization. This talk described the design functions performed and iden-tified responsible personnel. Enclosure 4 contains data that identifies the design organization.

A presentation on the organization of the Vogtle Project Verification and Validation Team was made. This talk described the verification and validation activities and identified responsible personnel. Enclosure 4 contains data that identifies the verification and validation organization.

Westinghouse personnel made a presentation on design differences between the South Texas Qualified Display Processing System and the Yogtle PSMS. The hardware and software differences between these systems were identified and discussed. Also, the Vogtle plant-specific design documentation was identified. Enclosure 5 contains a copy of the visual aids used during the presentations. ,

The staff audited the design documentation. A major difference between the Vogtle design and the South Texas design is the reactor vessel level instrumentation. This difference results in instrument unique data proces-sing algorithms in the design.

Westinghouse personnel discussed the design verification and validation program. This program was used in the development of the display system.

The object of this program is to eliminate errors in the design. Enclosure 6 contains a copy of the visual aids used during the presentation. The method used by the validators to identify the tests for the display system was also discussed. This discussion identified the scope of the tests 8707240149 e70720 PDR ADOCK 05000424 P PDR

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consisting of functional, abnormal, and prudence evaluations. The functional evaluation of the display system contained static as well as dynamic tests of the display system. Also, the validation effort focused upon the differ- j ences between the Vogtle design and the South Texas design.

A demonstration of one channel of the display system was conducted by Westing-house personnel. During the demonstration, the staff visually inspected the hardware cabinets of the display system. The demonstration also illustrated the use of the keyboard and several of the display formats. The display device is a gas plasma display similar to the one used in the South Texas j design. 1 The demonstration also illustrated the coding used to identify poor, suspect, and bad data. These data types are established from the algorithm processing of plant sensor data.

l The audit of the design documentation consisted of two major activities.

The first major activity consisted of an on-paper walk through of two sensor signals through the display system. The second major activity consisted of an evaluation and analysis of the errors identified and corrected during the verification and validation effort.

The walk through of sensor signals began at the sensor. The sensor signals evaluated consisted of cold leg temperature (primary coolant system) and auxiliary feedwater flow (secondary coolant system). The analog sensor signals were traced through the signal conditioning circuits to the multiplexors. At the multiplexer, the analog sensor signal is converted to a digital signal. The processing of the digital signals by the micro-processor stored algorithms was evaluated. The processed signal was traced to the display surface of the gas plasma display. Verification and validation activities associated with these signals were also evaluated as part of the walk through.

The second major activity of documentation evaluation audited the errors identified and corrected by the verification and validation program.

Enclosure 7 contains a summary of the errors identified from the verifi-cation and validation program. This enclosure also cor.tains a summary of the resolution of the validation identified errors.

The licensee presented and discussed physical security measures and maintenance for the display system. Security measures were discussed for the remote processing units, the data processing units, and the displays.

Also security measures for the spare PROMS (programable read only memories) were discussed. Maintenance and modification to the system were also discussed. Enclosure 8 contains a copy of the visual aids used during the discussion.

This meeting sumary was prepared based on input provided by Leo Beltracchi.

I I Mela\Y nie A. Miller, Project Manager 1 Project Directorate II-3 Division of Reactor Projects, I/II

Enclosure:

As stated cc: See next page b PD#Il Qbl/II PDir RP-I/II MMillIk/mac

M'"' BJYoNoblood

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consisting of functional, abnormal', and prudence evaluations. The functional evaluation of the display system contained static as well as dynamic tests of the display system. Also, the validation effort focused upon the differ-ences between the Vogtle design and the South Texas design.

A demonstration of one channel of the display system was conducted by Westing-house personnel. During the demonstration, the staff visually inspected the hardware cabinets of the display system. The demonstration also illustrated )

the use of the keyboard and several of the display formats. The display i device is a gas plasma display similar to the one used in the South Texas j design.

l i

The demonstration also illustrated the coding used to identify poor, suspect, and bad data. These data types are established from the algorithm processing of plant sensor data, i

The audit of the design documentation consisted of two major activities.

The first major activity consisted of an on-paper walk through of two sensor j signals through the display system. The second major activity consisted of l an evaluation and analysis of the errors identified and corrected during the verification and validation effort.

The walk through of sensor signals began at the sensor. The sensor signals evaluated consisted of cold leg temperature (primary coolant system) and auxiliary feedwater flow (secondary coolant system). The analog sensor ,

i signals were traced through the signal conditioning circuits to the l multiplexors. At the multiplexer, the analog sensor signa; is converted i to a digital signal. The processing of the digital signals by the micro-processor stored algorithms was evaluated. The processed signal was traced to the display surface of the gas plasma display. Verification and validation activities associated with these signals were also evaluated as part of the walk through.

The second major activity of documentation evaluation audited the errors ,

identified and corrected by the verification and validation program. l Enclosure 7 contains a surmary of the errors identified from the verifi-  !

cation and validation program. This enclosure also contains a summary of I the resolution of the validation identified errors.

The licensee presented and discussed physical security measures and i maintenance for the display system. Security measures were discussed for '

the remote processing units, the data processing units, and the displays.

Also security measures for the spare PROMS (programmable read only memories)  !

were discussed. Maintenance and modification to the system were also ,

discussed. Enclosure 8 contains a copy of the visual aids used during the discussion.

This meeting sumary was prepared based on input provided by Leo Beltracchi.

Qfa [L h '

Helanie A. Miller, Project Manager Project Directorate II-3 Division of Reactor Projects, I/II

Enclosure:

As stated cc: See next page

Mr. H. B. Tucker Duke Power Company McGuire Nuclear Station I

cc:

Mr. A.V. Carr, Esq. Dr. John M. Barry Duke Power Company Department of Environmental Health P. O. Box 33189 Mecklenburg County 422 South Church Street 1200 Blythe Boulevard Charlotte, North Carolina 28242 Charlotte, North Carolina 28203 County Manager of Mecklenburg County 720 East Fourth Street Charlotte, North Carolina 28202 l

Chairman, North Carolina Utilities Commission Mr. Robert Gill Dobbs Building Duke Power Company 430 North Salisbury Street Nuclear Production Department Raleigh, North Carolina 27602 i P. O. Box 33189 Charlotte, North Carolina - 28242 Mr. Dayne H. Brown, Chief Radiation Protection Branch J. Michael McGarry, III, Esq. . Division of Facility Services Bishoo, Liberman, Cook, Purcell Department of Human Resources and Reynolds 701 Barbour Drive

-1200 Seventeenth Street, N.W. Raleigh, North Carolina 27603-2008 l Washington, D. C. 20036 1

l Senior Resident Inspector c/o U.S. Nuclear Regulatory Commission Route 4, Box 529 Hunterville, North Carolina 28078 i Regional Administrator, Region II I

U.S. Nuclear Regulatory Commission, i 101 Marietta Street, N.W. , Suite 2900 Atlanta, Georgia 30323 l i

l L. L. Williams Area Manager, Mid-South Area ESSD Projects Westinghouse Electric Corporation MNC West Tower - Bay 239 P'. O. Box 355 I l Pittsburgh, Pennsylvania 15230 l l

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MEETING

SUMMARY

DISTRIBUTION Docket File -

NRC Partici) ants-NRC PDR L. Beltracc;11 L PDR NSIC PRC System PD#II-3 Rdg-Project Manager M. Miller M. Duncan l - B. Kolostyak W. Troskoski (MNBB 6113)

OGC-Bethesda ACRS (10) e .

OTHERS.

i bec: Licensee & Service List l

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_ _ _ . _ - - . _ _ . _ . _ _ _ _ - - - _ - - _ _ - . -l

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Enclosure 1 Participants 9

NRC Southern Company L. Beltracchi J. Bailey i

SOHAR,.Inc. Westir.ghouse J. Frawley A. Blanchard W. Ciaramitaro Georiga Power Company F. Bednar

.D. Morrison J. Aufdenkampe* G. Lang T. Hantz D. Therault l J. Rindfuss A. Negus  !

W. C. Gangloff '

T. G. Weiss C. Senton C. Vernon l Attended June 30, 1987 only 4

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.- . ENCLOSURE 2

1. INTRODUCTION 1 HOUR

1. PURPOSE

2. SCHEDULE

3. PROPRIETARY MATERIAL /AL91T REPORT

4. ORGANIZATIONAL STRUCTURE (DESIGN AND V&V)

II. PSMS DESIGN DIFFERENCES 1 HOUR

1. HARDWARE DIFFERENCES

2. SOFTWARE DIFFERENCES

3. FUNCTIONAL REQUIREMENT DIFFERENCES

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III. VERIFICATION AND VALIDATION PHILOSOPHY 2 HOURS

1. OVERVIEW

2. DETERMINATION OF SOFTWARE DIFFERENCES

3. VALIDATION TESTING PHILOSOPHY IV. SYSTEM DEMONSTRATION 1 HOUR

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V. REVIEW 0F PSMS DOCUMENTATION 8 HOURS

1. REVIEW 0F V&V CLARIFICATION AND TROUBLE RFPORTS

2. SELECTION OF THREAD PATHS

' VARIABLES (TCOLD, AFW)

' ABNORMAL TESTING (SUBC00 LING)

'PRUDENCY (RPU/DPU/SPDS DATALINK)

A. DESIGN DOCUMENTATION Bt VERIFICATION DOCUMENTATION C. VALIDATION DOCUMENTATION 2928N: S8/ GEL /487 2.'1

l. - -ENCLOSURE 2- 'G 1

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VI. PSMS SECURITY l

1. - PSMS ACCESSABILITY.

2. PROM PHYSICAL SECURITY

3. MAINTENANCE AND UPGRADES

4. SITE TEST PROGRAM l.:, u

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SUMMARY

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ENCLOSURE 5-i HARDWARE DIFFERENCES l

l. 0 ONE DIFFERENT I/O BOARD 0 PLANT SPECIFIC KEYB0ARD LAYOUT-C' O ONE PLASMA DISPLAY PER TRAIN st; O HALF BAY RPU AND DPU CABINETS O RPU AND DPU DATA LINK BOARD l

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5.1-2928N:61/ GEL /487

, ,' ENCLOSURE 5 SOFTWARF DIFFERENCES O CORE EXIT THERM 0 COUPLES - E'

_p y. p SHARED. THERMOCOUPLE BETWEEN QUADRANTS CORE MAXIMUM THERM 0 COUPLE COMPUTED TEMPERATURE INSTEAD OF FIFTH HOTTEST o RVLIS (WESTINGHOUSE VS, CE)

UPPER RANGE $;. .;

FULL RANGE DYNAMIC HEAD O DISPLAY FORMATS SPECIFIC TO PLANT V0GTLE O PAMS VARIABLES SPECIFIC TO PLANT V0GTLE ,

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0 ENGINEERING UNIT CONVERSION plzq W #

VALVE STATUS ALGORITHM ' M 0 ALARM / CAUTION INDICATION g .

ANNUNCIATOR WINDOW THERMOCOUPLE RELATED INDICATIONS i

2928N: 60/ GEL /487 5.2

l 14 ENCLOSURE 5 PLANT SPECIFIC DOCUMENTATION O POST ACCIDENT MONITORING SYSTEM FUNCTIONAL

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REQUIREMENTS .O YU', Y'M4 j

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0 REACTOR VESSEL LEVEL INDICATION SYSTEM FUNCTIONAL REQUIREMENTS'

. O MAN-MACHINE INTERFACE DESIGN BASIS AND

. FUNCTIONAL REQUIREMENTS

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, -3 , _-;.: g q ENCLOSURE 6' 7 7 -l 3 ,

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l VALIDATION EFFOR'T  !

FOR VOGTLE PSMS-1 JUNE 26,1987 l

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Westinghouse Nuclear Technology Systems Division I i

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. 6.1

ENCLO5URE 6 VALIDATION EFFORT o DECOMPOSE FUNCTIONAL REQUIREMENTS o GENERATE TEST PROCEDURES j 1

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o TEST AND ANALYZE RESULTS

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o GENERATE TROUBLE REPORTS j o DOCUMENT RESULTS IN A DATA BASE o RETEST TO CONFIRM PROBLEM AREAS i

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6.2 l C -

. _ , ," ENCLOSURE 6 I

VAllDATION PHILOSOPHY _

o- FUNCTIONAL REQUIREMENT DISPLAY INTEGRITY .;

STEADY STATE CHARACTERISTICS l TRANSIENT CHARACTERISTICS

,f , o ABNORMAL CONDITION OUT OF RANGE INPUTS.(OFFSCALES)

• OVERLOAD AND RECOVERY-o PRUDENCY NOT ADDRESSED IN THE DECOMPOSITION VERIFY " SOUND" DESIGN PRACTICE 1

l 6.3 .

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.. . .. ENCLOSURE 6 73 VAllDATION PHILOSOPHY f

a CONCENTRATE ON DIFFERENCES o PROVE THAT INPUTS ARE MAPPED PROPERLY TO EACH

-DISPLAY

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o PROVE TgT ALL ALGORITHMS HAVE BEEN INSTALLED

_ . . PROPERLY o DOCUMENT RESULTS. ON FUNCTIONAL REQUIREMENT DATA BASE 4

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____a--______-_-_-----_---------- - - - - - - - - - - - - - - - - - - - - - - - - -

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. .- . ENCLOSURE 6 I VAllDATION TECHNIOUE )

3 o VERIFY FIRMWARE CONGRUENCE' HAR D'NARE l l

ONE 100 OHM RTD INPUT SOFTWARE

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IDENTIFY ALGORITHMS COMMON TO SOUTH TEXAS SAMPLE TO VERIFY CODE IMPLEMENTED IN CORE ALGORITHMS IS THE SAME I PROVE' INPUT TO OUTPUT INTEGRITY  ;

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l 6.5 '

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. l ENCLOSURE 6 l i

COMMON ALGORIT HMS, j l

o REDUNDANT SENSOR ALGORITHM 1 1

o RCS SUBCOOLING o CORE EXIT THERMOCOUPLE / REFERENCE JUNCTION BOX i

l o HEATUP/COOLDOWN RATE l

o DPU MISMATCH -

o RPU/DPU STATUS INDICATION

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6.6 _-_ - _ _____- - -

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. , . , ENCLOSURE 6 i

l VALIDATION TECHNIOUES o STATIC DISPLAY TEST - DPSP.0387.0 l l L -

ACRONYMS SPECIAL DISPLAY REQUIREMENTS DISPLAY PAGE FORMAT: DISPLAY HEADER, ACTIVE AREA, MESSAGE AREA '

,f , o DYNAMIC DISPLAY TEST - DSPD.0487.0 CREATION TIME UPDATE RATE TIME RESPONSE OVERLOAD AND RECOVERY l

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i 6.7 I

' ENCLOSURE 6 ,

l RVLIS TESTS - VRVLIS,0487.0 o RVLIS REQUIREMENTS RVLIS: SECTION 21 RVLIS REQUIREMENTS PT6: PAGE 6 PRIMARY TRENDS RV LVL DISPLAY RVLD: REACTOR VESSEL LEVEL DISPLAY l

o SENSORS RELATED TO RVLIS P. VAR.007: REACTOR VESSEL WATER LEVEL RSA I

P. VAR.021: RCP STATUS P. VAR.022: CAPILLARY LINE TEMPERATURE SENSORS P. VAR.023: HYDRAULIC ISOLATION STATUS l P. VAR.024: UNCOMPENSATED' dp TRANSMITTERS .;

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' 6.8 9

,' ENCf.05URE 6 SYSTEM TESTS - VSYS.0487.0 o RANGE, TREND AND ALARM TESTS: APPENDIX B- -

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o SUMP AND CONTAINMENT WATER LEVEL: APPENDIX C o HEATUP AND COOLDOWN RATE: APPENDIX D l

o REFERENCE JUNCTION RTDs: APPENDIX E I o CORE EXIT THERMOCOUPLE: APPENDIX F ')

.  ;.I o REDUNDANT SENSOR ALGORITHM TEST: APPENDIX G j

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• SAMPLE TWO, THREE AND FOUR SENSOR CASES o PRESSURIZER SAFETY VALVE TEST: APPENDIX H .

o DPU MANUA'L ENTRY VALUE: APPENDIX 1 d l

o ERF DATA LINK TEST: APPENDIX J $

l o LOSS OF POWER: APPENDIX K d o DPU MISMATCH: APPENDIX M P

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l I l 1 l' 6.9 j

.,,.- [ ENCLOSURE 6 DIFFERENT ALGORITHMS l ,

1 o CORE MAX THERMOCOUPLE o RVLIS ALGORITHMS t

0 0

.6.10

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,- .' ENCLOSURE 6

'" o PSMS FUNCTIONAL TEST-(Performed Following V&V PROM Changeout) i 1

i e Testing duplication of preoperational test effort i e Test method-Verification of displays Diagnostic status block verification I Digital signal verification Analog signal verification Trend verification Suspect and mismatch check l

e Schedule 1

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. ,.' ENCLOSURE '7 Verification Error Type Summary ErrorType43(t.N)

T treerType41(17.8) gr,or Type 8 (23.5).

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R . Error Type 3 (2. M Error Tyya 34 (1. 3) E 5 Er m Type 7 (1.3 f ErrorTypeat(1.2) Error Type 13 (1.3l IPrer Type N,(17. n}

- E7Per Type 40 (it.5)

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64 Trouble Reports 80 Total Error Types Figure 3 )

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• Prete se.netties (ts.n)

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• 14 Trouble Reports-30 Total Error Types Figure 5 o

O 7.3

ENCLOSURE 8 PSMS PHYSICAL SECURITY e RPUs and DPUs Located in vital area PROM removal results in data errors on display Cabinets lockable e Plasma Display Located in Control Room (vital area)

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Directly observable by operator Cabinets lockable .

e Spare PROMS Stored in warehouse:

a) Warehouse in protected area b) Access limited to warehouse personnel (all others require escort) c) Maintained Class B storage Removal requires MER (MER generally requires MWO for parts issue) l l

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- ENCLOSURE 8 PSMS MAINTENANCE AND MODIFICATION e Maintenance All maintenance reouires MWO

- MWO reviewed by:

i a) operations b) maintenance engineering 1

c) quality control

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, d) health physics and chemistry (if applicable)

- Retest required after maintenance e) 1.evel of retest depends on maintenance e Modifications All modifications handled as desien chances  !

l - Design changes subject to original design requirements i

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- All verifications performed originally required on design i modification

- Retesting subject to original requirements 8.2

_ _ _ _ _ _ _