ML20012C281

Forwards Suppl 3 to Qualified Display Processing Sys (Qdps) Verification & Validation Process Final Rept & Summary of Qualified Display Processing Sys (Qdps) Recurring Component Failure Data.

ML20012C281
Person / Time
Site:	South Texas
Issue date:	03/12/1990
From:	Mcburnett M HOUSTON LIGHTING & POWER CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
Shared Package
ML20012C282	List: ML20012C281 ML20012C283 ML20012C284
References
ST-HL-AE-3393, NUDOCS 9003200440
Download: ML20012C281 (4)

Text

4 The Light co mpany South Tezu Project Electric Generating P.O.Bos289 Station Wadsworth. Tesas 77483 Houston Lighting & Power March 12, 1990 ST-HL-AE-3393 File No.: G4.2, J41.1 G9.17 10CTR50 U. S. Nuclear Regulatory Commission Attention Document Control Desk Washington, DC 20555 South Texas Project Electric Generating Station Units 1 and 2 Docket Nos. STN 50-498, STN 50-499 submittal of supplement 3 to the QDPs Verification and Validation Process Final Report and Update on the system Performance Reference A. Safety Evaluation Report Related to the Operation of South Texas Project Units 1 and 2, NUREG-0781, Supplement No. 3; dated May 1987.

B. Submittal of Supplement 1 to the QDPS Verification and Validation Program Final Report; M. R. Wisenburg, HL&P, Letter to the NRC; ST-HL-AE-1988; dated Harch 19, 1987.

C. Response to NRC Concerns Identified During an Onsite Assessment of the Qualified Display Processing System; M. A. McBurnett, HL&P, Letter to the NRC; ST-HL-AE-2859; dated November 22, 1988.

D. Submittal of Supplement 2 to the QDPS Verification and Validation Program Final Report; M. A. McDurnett, HL&P, Letter to the NRC; ST-HL-AE-2916; dated January 30, 1989.

E. Licensee Event Report 88-014 Revision 01 Regarding Reactor Protection System Actuation Due to a Software Problem in the Qualified Display Processing System; G. E. Vaughn, HL&P, Letter to the NRC; ST-HL-AE-2601; dated April 7, 1988.

This letter completes HL&P's commitment to keep the NRC informed of QDPS operational performance during the first operating cycle.

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THC/QDPS0390.LTR A Subsidiary of Ilouston Industries incorporated 9003200440 900312 CT PDR- ADOCK 05000498 P- PDC

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l. '.. l Houston Lighting & Power Company South Texas Project Dectric Generating Station  !

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$1 ML M 3393 Pope 2 of 4 l l

The Qualified Display Processing System (QDPS) is a microprocessor based i

, system which performs several safety related functions at the South Texas )

I Project. A comprehensive Verification and Validation (V&V) program was implemented to ensure that the system would perform in accordance with its functional requirements. Review of the QDPS design and V&V program involved a number of audits, site visite, and meetings with the NRC staff. l As stated in Reference A, the NRC staff requested to be kept informed of 1 problems encountered and any changes made to the QDPS during the first j operating cycle. This was to provide the staff a basis for evaluating the '

reliability of the system. HL&P committed to keep the Staff informed in References B and C. Reference D described the changes incorporated into the l Unit 2 QDPS prior to Fuel Load and the V&V results for those software changes. 1 The same changes have now been incorporated into the Unit 1 QDPS. I Reference E reported an event concerning behavior of the Temperature l Averaging Scheme (TAS) portion of QDPS during a plant cool down. This was the j only significant anomaly observed in operation of the QDPS. The TAS algorithm i has been revised to eliminate the problem, and the revised firmware has been installed in Unit 1. These same changes will be implemented in Unit 2 during its first refueling outage.

Supplement 3 to the QDPS V&V Final Report is provided in Attachment I. l It describen the TAS algorithm change and several other minor software l modifications included in the same change package. The on line parameter update (oLPU) capability described in Attachment I had not been delivered when the Unit 1 first refueling outage occurred and is presently planned for j installation during the second refueling outage. The entire package is j planned for installation in Unit 2 during the first refueling outage. l l

QDPS component failure data for STP Unit 1 from fuel load (August 1987) through August 1988 was provided in Reference C. Five cases were identified where a component demonstrated more than one failure during that period. l Attachment II provides data, in the same format as previously used, covering I the period from August 1988 through February 1990 for Unit 1 and the period l from fuel load (December 16, 1988) through February 1990 for Unit 2. As in l the earlier report, only component types with more than one failure are  ;

generally reported; however, those component types previously listed are j included, listing the actual number of failures. I l

There have been no failures to date which resulted in a system outage. l The QDPS has demonstrated 100% operational availability in both Units in that l the system has been available in accordance with the Technical Specifications on a continuous basis to support plant operations since fuel load.

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I T HC/CDPS0370.LTR

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. o Houston Lighting & Power Company South Texas Project Electric Gents. ting Station i l' ST ML AE 3393 Pepe 3 of 4 If you have any questions on this matter, please contact ,

Mr. A. W. Harrison at (512) 972-7298 or myself at (512) 972-8530. -

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. A. McBurn ett & / ,

! Manager, Licensing I SDP/the Attachments: 1. Supplement 3 to the Qualified Display Processing System Verification and Validation Process Final Report for the '

South Texas Project II. Summary of QDPS Recurring Component Failure Data i THC/QDPS0390.LTR

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ST.HL+AE.3393 i Houston Ligh@g k Power Company File No.: 04.2 i

. South Texas hy,ect Electric Generating Station p g. 4 p ,

cc: ,

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. Regional Administrator, Region IV Rufus S. Scott ,

Nuclear Regulatory Coinmission Associate General Counsel 611 Ryan Plaza Drive, Suite 1000 Houston Lighting & Power Company Arlington, TX 76011 P. O. Box 61867 c- Houston, TX 77208 George Dick, Project Manager U.S. Nuclear Regulatory Commission INPO I Washington, DC 20$$$ Records Center .

1100 Circle 75 Parkway 5

'J. 1. Tapia Atlanta, GA 30339 3064  ;

Senior Resident Inspector -l' c/o U. S. Nuclear Regulatory Dr. Joseph M. Hendrie  ;

commission 50 Be11 port Lane P. O. Box 910 Be11 port, NY 11713  ;

.. Bay City, TX 77414 i D. K. Lacker b J. R. Newman, Esquire Bureau of Radiation Control  !

Newman & Holtzinger, P.C. Texas Department of Health l l 1615 L Street, N.W.- 1100 West 49th Street Washington, DC 20036 Austin, TX 78704 D. E. Ward /R. P. Verret ,

Central Power & Light Company P. O. Box _2121

i. . Corpus Christi, TX 78403 Jr C. Lanier t Director of Generation City of Austin Electric Utility- l 721 Barton Springs Road  ;

Austin, TX 78704 '

t R. J. Costello/M. T. Hardt City Public Service Board P. O. Box 1771 ,

San Antonio, TX 78296  ;

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Revised 12/15/89 t

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