ML13078A250

03/21/2013 Licensee Meeting Slides Re Joseph M. Farley Nuclear Plant NFPA 805 Fire Modeling LAR Submittal - Session 4

ML13078A250
Person / Time
Site:	Farley
Issue date:	03/19/2013
From:	Southern Nuclear Operating Co
To:	Division of Operating Reactor Licensing
Brown E
Shared Package
ML13078A284	List: ML13078A245 ML13078A246 ML13078A247 ML13078A248 ML13078A250 ML13078A251 ML13078A252 ML13078A253 ML13078A255
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Download: ML13078A250 (14)

Text

FNP NFPA 805 LAR Submittal Overview March 19-21, 2013 Circuit Analysis

Summary

• Circuit Analysis Process and Controls

• A l t Qualifications Analyst Q lifi ti

• Governing Analysis Criteria

• NSCA SC vs. PRA

• Analysis Methodology

• Circuit Analysis Database

• Associated Circuits Circuit Analysis Slide 2 of 14

Process and Controls

• Circuit Analysis Process

- Performed IAW approved procedure

- Strict and formal analysis conventions

- Emphasis on consistency and standardization

- Integrated PRA and NSCA requirements

• Controls

- Rigidly defined Function States

- Independent verification for each analysis

- Detailed documentation in database (FDM/ARCPlus)

Circuit Analysis Slide 3 of 14

Analyst Qualifications

• All analysts formally qualified to SNC &

Contractor QUAL CARD for independent work

• Internalized industry lessons learned on training, qualifications and oversight qualifications,

• Procedure and database established to force consistency

• Maintained awareness of dual use - PRA and NSCA Circuit Analysis Slide 4 of 14

Governing Criteria

• NEI 00-01, Rev.1

- Initial Work to Rev.1

- Gap analysis performed to Rev. 2 (per Generic RAI 10 and RG 1.205)

• NEI 00-01 00 01, Rev Rev. 2

- Later work

- Integrated emerging PIRT issues

- No N creditdit ttaken k ffor off-scheme ff h exclusions l i

• NUREG/CR-6850

- Included Open p circuits Note: Integrated requirements for conservative, but universal criteria between PRA and NSCA Circuit Analysis Slide 5 of 14

NSCA vs. PRA

• Implementing Concepts

- 95% of circuit analysis y criteria for PRA and NSCA are the same

• Establish single dataset for criteria to assure dual use and better interface between NSCA and PRA

• Provide procedure and database flexibility to accommodate the 5% difference

- Long Long-term term configuration control extremely difficult if redundant data sets are maintained

- Differences p primarily y handled through: g

• Use of Function States

• Interlock identification and documentation Circuit Analysis Slide 6 of 14

Analysis Methodology

• All circuit analysis drive by FUNCTION STATES

• Function States

- Component + Initial State + Desired State

- Permits maximum flexibility to accommodate PRA and NSCA differences (primarily auto signals)

- Minimize false failures up front

- Efficient Effi i t and d lless error prone

- Consistent with NUREG/CR-6850 methods for Tasks 3&9 Circuit Analysis Slide 7 of 14

Analysis Methodology, cont

• Work package development to facilitate process

• Single, controlled database (FDM)

• Process and techniques based on NRC/EPRI training g modules

• Major Steps Prerequisites q satisfied

• Function state established

• Plant specific rules and conventions

• General classification

• Resolve questions Circuit Analysis Slide 8 of 14

Analysis Methodology, cont

• Major Steps Work Package g Development p

• Drawings

• Supplemental information Cable Selection

• All scheme cables dispositioned

• Fault codes applied to all cables

• Basis documented for excluded cables

• Selection of required cables with hot probe method

• Cables generally excluded based only on design features at this stage (NUREG/CR-6850 concept)

Circuit Analysis Slide 9 of 14

Analysis Methodology, cont

• Major Steps Power Supply pp y Identification

• All Power Supplies identified

• Required and not-required determined based on Function State requirements

• Sensitive to alternate PS lineups and how they are credited Dependencies & Interlocks

• All circuit interlocks formally dispositioned

• Equipment dependencies established or off-scheme cables directly incorporated

• Differentiate auto functions so NSCA and PRA can apply as credited by Basic Event Circuit Analysis Slide 10 of 14

Analysis Methodology, cont

• Major Steps Documentation

• Controlled database, with individual analysis originate and check sign-offs

• Reference drawing

• Final calculation for circuit analysis and PRA Notebook Circuit Analysis Slide 11 of 14

Circuit Analysis Database Circuit Analysis Slide 12 of 14

Associated Circuits

• Electrical Coordination

- Consolidated calculation

- Addresses NSCA & PRA

• Common Enclosure

- Addresses secondary fire concerns

- Addresses loss of DC control power to Switchgear

• CPT Open Circuits

- Followed PIRT recommendations

• MHIF Analysis

- Followed NEI 00-01, Appendix B method Circuit Analysis Slide 13 of 14

Q Questions ti  ?

Circuit Analysis Slide 14 of 14