ML20041A982

RO 82-06/01P:on 811203,control Power Fuses 16F301A,16F302A, 16F303A & 16F304A Removed from Svc for Maint on Electromatic Relief Valve Pressure Switch,Rendering Valve a & Automatic Depressurization Sys Inoperable.Switch Replaced

ML20041A982
Person / Time
Site:	Oyster Creek
Issue date:	02/11/1982
From:	Fiedler P JERSEY CENTRAL POWER & LIGHT CO.
To:	Haynes R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
References
RO-82-06-01P, RO-82-6-1P, NUDOCS 8202230120
Download: ML20041A982 (3)

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Certified By N'/.4.[ M Mh4n  %

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'10: Ibnald C. Haynes l Administrator of Regulatory Operations Pagion I 631 Park Avenue ~ i King of Prussia, Pennsylv - 4 j

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FI O4: Jersey Central Power & L1 Cm Oyster Creek Nuclear Gen Statio E Docket No. 50-219 m _d Forked River, New Jersey 08731 SUDJlrt: Reportable Occurrence Report No. 50-219/82-06/0lP-The following is a preliminary report being subnitted in empliance with the Technical Specifications, paragraph 6.9.2.a(2) .

i PreliminaryApprova5.: D' h P. B. Fiedler Vice President - Director Oyster Creek l

Director (2)

Office of Management Information and Program Control U.S. Nuclear Regulatory Cmmhision Washington, D. C. 20555 NRC Resident Inspector (1)

Oyster Creek Nuclear Generating Station Forked River, N. J.

8202230120 820211 PDR S ADDCK 05000219 PDR

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OYSTER CREEK NUCLEAR GENERATING STATION Forked River, New Jersey 08731 Licensee . Event Report Reportable Occurrence No. 50-219 /82-06/0lP Repo rt Date February 11, 1982 Occurrence Date December 3,1981 Identification of Occurrence While performing maintenance activities to repair a faulty Electromatic Relief Valve pressure switch, d.c. control power fuses 16F301A,16F302A, 16F303A, and 16F304A were removed. This rendered Electromatic Relief Valve "A", and one .

Trip System in the Automatic Depressurization System (ADS) inoperable. This was discovered on February 10, 1982, during the review of information concerning the microswitch replacement. v3.pc .

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This event is considered to be a reportable occurrence as defined in the -

Technical Specificaticus, paragraph 6.9.2.a.(2). .

Conditions Itior to Occurrence Major Plant Parameters were as follows:

Power: Reactor 1858 MWt Genera tor 650 MWe Flow: Recirculation 15.3 x 104 gPm Feedwater 6.6-x 106 lbs /h r.

Description of Occurrence On December 3,1981, the "A" Electromatic Relief Valve (EMRV) lif ted and immediately reseated.. Surveillance testing was performed and pressure sensor.

IA-83A was found defective. Corrective maintenance was performed to- replace the defective pressure sensor. Prior to commencing the corrective maintenance, d.c. power fuses 16F301A,16F302A, 16F303A, and 16F304A were removed.

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Reportable Occurrence Page 2 Report No. 50-219/82-06/0lP Apparent Cause of Occurrence ,

• C3 a "p The 'cause of the trip system inoperability is attributed to personnel error in-that the consequences of removing the control power- fuses was not recognized for its effect on the ADS control logic.

Analysis of Occurrence The functions of the Electromatic Relici Valves are to provide a means for a controlled rapid blowdown of the reactor pressure vessel during a small pipe.

braak and to automatically relieve a vessel overpressure condition.

Removal of the D.C. control power fuses resulted in the inoperability of "A" ,

EMRV and the loss of one trip system of the Automatic Depressurization Syctem (ADS). The redundant trip system was still operable. Had a condition been present which required the operation of the ADS, the redundant systen' would have actuated the tour remaining valves to depressurize the reactor.

Co r re c t ive Ac t ion As an immediate action, the reactor pressure was reduced to 1010 lbs. and the isolation condenser valves were demonstrated to be operable in accordance with the Technical Specification requirements. Pressure sensor IA-83A was repleced with a new switch.

On the basis of the micrc. witch report, B, C, D,' and E EMRV pressure sensors (uld Model ::c, E20 ht2SS) were replaced with 125VDC rated (Model No. B2S-Mi2SS) switches. Transient suppression devices (metal oxide varistors) were installed across the solenoid and relay coils of all sensors.

\ . Failure Data Manu fac turer: Earksdale Modci No: B2S-Hi?SS t-w -. , . . -