ML18038B390

Provides Rev to Commitments to Perform Testing of Static o-ring Differential Pressure Switches & Voltage Verification Testing of Reactor Protective Sys Equipment

ML18038B390
Person / Time
Site:	Browns Ferry
Issue date:	08/17/1995
From:	Salas P TENNESSEE VALLEY AUTHORITY
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
NUDOCS 9508220207
Download: ML18038B390 (9)

Text

PRIORITY 1 (ACCELERATED RZDS PROCESSING) i~GULATORY XNFORMATION DXSTRIBUTION SYSTEM (RIDS)

ACCESSION NBR:9508220207 DOC.DATE: 95/08/17 NOTARIZED: NO FACIL:50-259 Browns Ferry Nuclear Power Station, Unit 1, Tennessee 50-296 Browns Ferry Nuclear Power Station, Unit 3, Tennessee AUTH.NAME AUTHOR AFFILIATION SALAS,P.

Tennessee Valley Authority RECIP.NAME RECIPIENT AFFILIATION Document Control Branch (Document Control Desk)

SUBJECT:

Provides rev to commitments to perform testing of static o-ring diferential pressure switches

& voltage verification testing of reactor protective sys equipment.

DISTRIBUTXON CODE:

D030D COPIES RECEIVED LTR ENCL SIZE:

TITLE: TVA Facilities Routine Correspondence NOTES:

DOCKET g 05000259 P

05000296 RECXPIENT ID CODE/NAME PD2-3 WILLIAMS,J.

INTERNAL: ACRS NRR/DSSA RES/DE/SSEB/SES EXTERNAL: NOAC COPIES LTTR ENCL 1

1 1

1 6

6 1

1 1

1 1

1 RECIPIENT ID CODE/NAME PD2-3-PD ILE CEN GP/HD NRC PDR COPIES LTTR ENCL 1

1 1

1 1

0 1

1 D

N NOTE TO ALL "RZDS" RECIPIENTS:

PLEASE HELP US TO REDUCE WASTEl CONTACT THE DOCUMENT CONTROL DESKi ROOM OWFN 5DS (415-2083)

TO ELIMINATE YOUR NAME FROM DISTRIBUTION LISTS FOR DOCUMENTS YOU DON'T NEED!

TOTAL NUMBER OF COPIES REQUIRED:

LTTR 15 ENCL 14

4

'Tennessee Valley Authority, Post Office Box 2000, Decatur, Alabama 35609 August: 17, 1995 U.S. Nuclear Regulatory Commission ATTN:

Document Control Desk Washington, D.C.

20555 Gentlemen:

In the Matter of Tennessee Valley Authority Docket Nos.

50-259 50-296 BROWNS FERRY NUCLEAR PLANT (BFN)

UNITS 1 AND 3 - REVISION TO COMMITMENTS TO PERFORM TESTING OF STATIC 0-RING DIFFERENTIAL PRESSURE SWITCHES AND VOLTAGE VERIFICATION TESTING OF REACTOR PROTECTIVE SYSTEM EQUIPMENT BFN is a participant in a pilot program for managing NRC commitments.

This program uses guidelines developed by the Nuclear Energy Institute (NEI) which include a uniform process for changing commitments.

The NEI guidelines provide for timely notification to the NRC when changing commitments which meet specified criteria.

Where timely notification is

required, the guidelines recommend this notification be accomplished by supplementing the docketed correspondence containing the original commitment.

Two commitments, originating from the referenced correspondence and described in the enclosure, have been evaluated for deletion using the NEI Guidelines.

Results of these evaluations indicate the completion of these commitments is no longer necessary.

This letter provides the results of our evaluations and provides notification of the deletion of these commitments for Units 1 and 3.

'st508220207 950817 PDR ADQt.K 05000259 p

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U.S. Nu'clear Regulatory Commission Page 2

August 17, 1995 There are no commitments contained in this correspondence.

If you have any questions, please contact me at (205) 729-2636.

S' l

Pedro al s Man er of Site Licensing Enclosure cc (Enclosure):

Mr. Mark S. Lesser, Acting Branch Chief U.S. Nuclear Regulatory Commission Region II 101 Marietta Street, NW, Suite 2900 Atlanta, Georgia 30323 NRC Resident Inspector Browns Ferry Nuclear Plant Route 12, Box 637

Athens, Alabama 35611 Mr. J.

F. Williams, Project Manager U.S. Nuclear Regulatory Commission One White Flint, North 11555 Rockville Pike Rockville, Maryland 20852 E. V. Imbro, NRR/RSIB U.S. Nuclear Regulatory Commission One White Flint, North 11555 Rockville Pike Rockville, Maryland 20852 E. J.

Leeds, NRR/DRPW U.S. Nuclear Regulatory Commission One White Flint, North 11555 Rockville Pike Rockville, Maryland 20852

U. S. Nuclear Regulatory Commission Page 3

August 17, 1995

References:

1. Letter from TVA to NRC dated July 20,

1987,

Response

to IE Bulletin 86-02, Static "0" Ring Differential Pressure Switches

2. Letter from TVA to NRC dated August 9,

1984,

Response

to Request for Additional Information, RPS Power Monitoring System Design Modifications

h 1

~ g t',C

ENCLOSURE TENNESSEE VALLEY AUTHORITY BROWNS FERRY NUCLEAR PLANT (BFN)

UNITS 1 AND 3 REVISION TO COMMITMENTS FOR UNITS l. AND 3 Current Commitment Statement Test static 0-ring (SOR) differential pressure (DP) switches every six months after initial calibration until two consecutive successful tests have been achieved.

Revised Commitment Statement N/A, This commitment is deleted for BFN units 1 and 3.

Source Document Letter from TVA to NRC dated July 20,

1987,

Response

to IE Bulletin 86-02, Static "0" Ring Differential Pressure Switches Basis for Commitment Change Bulletin 86-02 was written as a result of setpoint drift problems associated with SOR DP switches.

Since the bulletin was written, the manufacturer has determined that static pressure on the switches cause a

shift in the setpoint (approximately five inches of water column per 1000 psi static pressure).

TVA has revised the appropriate setpoint.

and scaling documents to address this error.

This ensures that the switches have the proper setpoints and are capable of performing their intended function.

This has adequately resolved the drift problem for these switches.

Since installation on Unit 2, the SOR DP switches have shown insignificant drift over two calibration intervals.

(Nominally an 18 month interval, the actual intervals ranged from 16 to 19 months.)

Current Commitment Statement Perform voltage verification testing for components supplied from Reactor Protective System (RPS) power supply.

Revised Commitment Statement N/A, This commitment is deleted for BFN units 1 and 3.

Source Document Letter from TVA to NRC dated August 9,

1984,

Response

to Request for Additional Information, RPS Power Monitoring System Design Modifications Basis for Commitment Change The commitment to perform the RPS voltage test was made to (1) determine if certain components supplied from the RPS Motor Generator (MG) sets needed to be replaced and determine the replacement requirements, and (2) measure the voltage drop from the RPS

MG sets to the supplied components to confirm the nssumptions used in establishing the Technical Specification setpoint values.

The basis for committing to perform the voltage test was the lack of detailed design basis information (cable routing, length, type) necessary to calculate, with sufficient precision, the expected voltage drops from the output of the MG sets to the supplied components.

Calculations which had been developed included additional conservatism to compensate for the lack of detailed design basis information.

Subsequent to the commitment to perform the RPS voltage

test, BFN established its design baseline verification program.

Included in this program were improvements in electrical design basis information and upgraded electrical calculations.

Implementation of the design baseline program resulted in significant improvements in TVA's analytical capability.

This improvement included the capability to determine by analysis, using industry standard methodology, voltage drops for the MG set supplied components using field verified cable installation data.

The subject RPS voltage verification test was performed on Unit 2 prior to its return to service.

The results of this test confirmed the design basis information as well as the analytical approach and methodology.

The configurations for Units 1 and 3 are similar to Unit 2.

TVA has developed similar improved design basis information for Unit 3 and has committed (TVA letter to NRC dated June 13,

1991, Design Baseline Verification Program) to develop similar improved design basis information for Unit 1.

The analytical approach and methodology are the same for Unit 3 as used for Unit 2.

The analytical approach and methodology for Unit 1 are expected to be consistent with that utilized for units 2

and 3.

Consequently, there is no longer a need to perform the RPS voltage test.

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