ELV-00909, Revised Special Rept Re Valid Diesel Generator Failure on 890719.Caused by Remote Gate Firing Module on Bridge Circuit 1.Rework on Module Completed & Circuit Returned to Svc

Revised Special Rept Re Valid Diesel Generator Failure on 890719.Caused by Remote Gate Firing Module on Bridge Circuit 1.Rework on Module Completed & Circuit Returned to Svc

ML20248C156
Person / Time
Site:	Vogtle
Issue date:	09/25/1989
From:	Hairston W GEORGIA POWER CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
ELV-00909, ELV-909, NUDOCS 8910030380
Download: ML20248C156 (2)

Text

4 L' (JPOrgia power COmDYG

• , . ", '333 Picamont Avernue Atlanta Georgra 30308 leiephone 404 526 3195 Ma.kno Address 40 invemess Center Par & way Post Ofhce Box 1295 Birmingham. Alabama 35201 Telephone 205 668 5561 e.v wuna.m vanc syntem

w. o. Hairston, n' September 25, 1989 Senior Wce President ELV-00909 Nuclear Operations 0023 i

Docket No. 50-424 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555 Gentlemen:

V0GTLE ELECTRIC GENERATING PLANT SPECIAL REPORT VALID DIESEL GENERATOR FAILURE In accordance with the requirements of the Vogtle Electric Generating Plant Technical Specifications 4.8.1.1.3 and 6.8.2, Georgia Power Company submitted -

a Special Report concerning a valid diesel generator failure by letter dated August 14, 1989 (ELV-00790). Enclosed is a revision to.this Special Report which corrects two typographical errors and updates the status of the repair work to correct the cause of the failure.

Sincerely, ,

,,.c W./. ICLf W. G. Hairston, III WGH,III/NJS/gm i

c(w): Georaia Power Company 1 Mr. C. K. McCoy  !

Mr. G. Bockhold, Jr. {

Mr. R. M. Odom '

Mr. P. D. Rushton NORMS ,

U. S. Nuclear Reaulatory Commission ,

l Mr. S. D. Ebneter, Regional Administrator Mr. J. B. Hopkins, Licensing Project Manager, NRR Mr. J. F. Rogge, Senior Resident Inspector, Vogtle

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$R20030380 s9o925 S .ADocM 0500o424 -

PNU  !

1. '. , ,.4 ENCLOSURE V0GTLE ELECTRIC GENERATING PLANT TECHNICAL SPECIFICATION SPECIAL REPORT 1-89-02 A. Requirement for Report This report is required in accordance with the Vogtle Electric Generating Plant's Technical Specifications, Section 4.8.1.1.3. This section of the Technical Specifications requires that all diesel-generator failures, valid or non-valid,. shall be reported to the Commission in a Special Report pursuant to Technical Specification -6.8.2.

B. Description of Valid Failure for Train B Diesel Generator On July 19, 1989, Diesel Generator IB was started for the monthly I surveillance testing and loaded to approximately 5000 KW when the operator noticed spikes in the current and KVAR meter readings. The l generator was taken off-line and the field voltage remained unstable.

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The diesel was stopped for further investigation by the system engineer.

The cause of the problem was believed to be in.the exciter bridge or-voltage regulator, so the bridge circuit was switched from bridge No. .I.

to bridge No. 2 and the diesel started. The surveillance was- completed ,

with no further problems. The cause has been determined to be the Remote Gate Firing Module on bridge circuit No. 1. Rework on the module {

was completed and bridge circuit No. I was returned to service.

C. Summary This failure, per Regulatory Guide 1.108, Section C.2.e.7, was the first-valid failure in the last 20 valid tests and the fourth.in the last' 52  !

valid tests, which is the total number of valid tests to date on Diesel J Generator IB.

Test frequency remains at 31 days in compliance with Table 4.8-l' of the i Technical Specifications.  ;

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