ML20084C526

AO 50-219/74-50:on 741004,cleanup Sys Dc Isolation Valve V-16-14 Failed to Close Electrically.Caused Undetermined. Arc Horn on Contactor 2Bc Replaced

ML20084C526
Person / Time
Site:	Oyster Creek
Issue date:	10/11/1974
From:	Ross D JERSEY CENTRAL POWER & LIGHT CO.
To:	Giambusso A US ATOMIC ENERGY COMMISSION (AEC)
References
AO-50-219-74-50, NUDOCS 8304080090
Download: ML20084C526 (3)

Text

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O O 7m Jersey Central Power & Light Company ? W'{ ~

MADISON AVENUE AT PUNCH BOWL ROAD e MORRISTOWN, N.J.07900

• 201539-6111

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October 11, 1974 1 A 9 "

g Mr. A. Giambusso Deputy Director for Reactor Projects

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Directorate of Licensing United States Atomic Energy Commission

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Washington, D. C. 20545 Q .',,jf:,k 4

Dear Mr. Giambusso:

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Subject:

Oyster Crock Statien #

Docket No. 50-219 Abnormal Occurrence Report No. 50-219/74-50

The purpose of this letter is to forward to you the attached Abnormal Occufrence Report in compliance with paragraph 6.6.2.a of the Technical Specifi-cations.

d Enclosed are forty copics of this submittal.

Vo truly yours,

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W Donald A. Ross Manager, Nuclear Generating Stations Pk Enclosures cc: Mr. J. P. O'Reilly, Director directorate of Regulatory Operations, Region 1 4L oom

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8304080090 741011 .

PDR ADOCK 05000219 S PDR COPY SENT REGION- _-

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o O Jersey Central Power & Light Company (f

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! MADISON AVENUE AT PUNCH BOWL ROAD

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OYSUIR CREEK NUCLEAR GENERATING STATION t FORKED RIVER, NEW JERSEY 08731 Abnormal Occurrence  ;

Report No. 50-219/74-50 Report Date October 11, 1974 Occurrence Date October 4, 1974 Identification of Occurrence Violation of the Technical Specifications, paragraph 3.5. A.1, failure of cleanup system DC isolation valve V-16-14 to close. Viis event is considered

• to be an abnormal occurrence as defined in the Technical Specifications, paragraph 1.15B.

Conditions Prior to Occurrence The plant was at steady state power with the following major parameters:

Power: Reactor,1905 FMt Electric, 655 FMe Recirculation, 15.8 x 104 gpm Flow:

Feedwater, 7.25 x 10 61b/hr Reactor Pressure: 1020 psig Stack Gas: 15,550 pCi/sec Description of Occurrence t

At 0830 on October 4,1974, while attempting to isolate the cleanup system for maintenance, it was found that cleanup system DC isolation valve V-16-14 failed to close electrically, Cleanup system AC isolation valve V-16-1 had previously closed normally. Electrical Department personnel were then dis-patched to the motor control center for V-16-14. An investigation revealed i ,

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• Abnormal Occurrenes-acport No. 50-219-74-50 Page 2 l' i i that the are horn on contactor 2Bc.was bent and restraining the moving

{ contactor in its closing motion. When the are horn was tapped, the moving '

) contactor was freed and V-16-14 subsequently closed.

I j- Apparent Cause of Occurrence -

l The investigation into the bending of the 2Bc are horn did not determine

{ the cause of the occurrence. The specific cause is, therefore, still j undetermined.

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Analysis of Occurrence i

a i

The safety significance of this event is the loss of cicanup system isolation I valve redundancy. Ilad a loss of coolant accident occurred generating a low-low reactor water level signal, V-16-1 would have closed to isolate the cleanup j system.

! Corrective Action i

Immediate corrective action involved replacing the are horn on the 2Bc con-

! tactor. Additional corrective action involved inspecting the are horns on i

all DC contactors in the same motor control center. None of these are horns j were found to be bent.

j Failure Data 1

Basic DC contactor data are as follows:

bbnufacturer - General Electric Company 600V - 25 amp

Identification No. - IC28001607 - F3G l

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