ML20065S300

Special Rept 94-004:on 940411,during Monthly Functional Test,Invalid Failure of EDG 13 Occurred Due to Personnel Error.Troubleshooting Run Performed & EDG Subsequently Tested Satisfactorily

ML20065S300
Person / Time
Site:	Grand Gulf
Issue date:	05/11/1994
From:	Hutchinson C ENTERGY OPERATIONS, INC.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
94-004, 94-4, GNRO-94-00076, GNRO-94-76, NUDOCS 9405180079
Download: ML20065S300 (2)

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May 11, 1994 '"'""'*"""

l U.S. Nuclear Regulatory Commission Mail Station P1-137 Washington, D.C. 20555 Attention: Document Control Desk  ;

Subject:

Grand Gulf Nuclear Station Unit 1 Docket No. 50-416 License No. NPF-29 Special Report 94-004 Invalid Failure of Emergency Diesel Generator 13 Due to Personnel Error GNRO-94/00076 j Gentlemen: )

l On April 11, 1994, plant personnel were performing the monthly functional test for Emergency Diesel Generator (EDG) 13. EDG 13 was started in accordance with plant procedures. The EDG reached rated speed and voltage.

Personnel synchronized the EDG to the associated bus and closed the EDG output breaker. The load was increased to 450 kW.

Subsequent to loading, personnel observed oscillations in EDG reactive power and exciter voltage. Attempts to reduce the noted oscillations were unsuccessful. Therefore EDG 13 was manually l

shut down to investigate the observed anomalies. The EDG ran for j approximately nine minutes prior to shutdown.

Upon investigating the oscillations, a troubleshooting run was performed. The previously observed oscillation did not recur. The EDG was sub7equently tested satisfactorily.

The cause of this occurrence could not be determined. However, it is suspected that the EDG output voltage setting may not have been correct during synchronizing.

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May ll, 1994 GNRO-94/00076 Page 2 of 3 The suspected cause of this occurrence would not have prevented the EDG from performing its intended function in the event of an emergency. Therefore the event is an invalid test and invalid failure as specified by RG 1.108. This invalid failure is being reported pursuant to GGNS Surveillance Requirement 4.8.1.1.3.

Yours truly, f-f ,

IUf/RR/

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cc: Mr. R. H. Bernhard Mr. 11 . W. Keiser Mr. R. B. McGehee Mr. N. S. Reynolds Mr. II . L. Thomas Mr. Stewart D. Ebneter Regional Administrator U.S. Nuclear Regulatory Commission Region II 101 Marietta St., N.W., Suite 2900 Atlanta, Georgia 30323 Mr. P. W. O'Connor (w/2)

Of fice of Nuclear Reactor Regulatiori U.S. Nuclear Regulatory Commission Mail Stop 13H3 Washington, D.C. 20555

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