ML19345E934

Forwards LER 81-001/03L-0

ML19345E934
Person / Time
Site:	Oyster Creek
Issue date:	01/30/1981
From:	Finfrock I JERSEY CENTRAL POWER & LIGHT CO.
To:	Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML19345E935	List: ML19345E934 ML19345E939
References
NUDOCS 8102060446
Download: ML19345E934 (3)

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7 OYSTER CREEK N NUCLEAR GENERATING STATION M

BL&B&Jlr 01 C;,57[f.M'l')f% (609) 693-1951 P.O. BOX 33S + F , KED RIVER

• NEW JERSFY

• C8731 c~ , u,. w,.,2ce January 30, 1981 Mr. Boyce H. Grier, Director Office of Irspn and Enforcement Region I United States Nuclear Regulatory Ccnrussion 641 Park Avmue King of Prussia, Pennsylvania 19406

Dear Mr. Grier:

SLH7ECT: Oyster Creek Nuclear Generating Station Docket. No. 50-219 Licensee Event Report Reportable Occurrence No. 50-219/81-01/3L This letter forwards three copies of a Licensee Event Report to r @ rt Reportable Occurrence No. 50-219/81-01/3L in ettpliance with paragraph 6.9.2.b.1 of the Technical Specifications. -

Very truly yours,

/ $48 van R. Finfrock, J .

Vice President -

l Director - Oyster Creek l IRF:dh Enclosures cc: Director (40 copies)

Office of Inspection and Enforcenent United States Nuclear Regulatory Camussion Washington, D.C. 20555 Director (3)

.. [6 Office of Management Information E ,'

and Program Control United States Nuclear Regulatory Ccmnission

~

Washington, D. C. 20555

' " ~

NPC Resident Insp@r (1)

Oyster Creek Nuclear Generating Station k.-

Forked River, N. J.

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OYSTER CREEK NIX 1 EAR GDiERATING STATICN Forked River, New Jersey 08731 Licensee Evm t Report Reportable Occurrence No. 50-219/81-01/3L Report Date January 30, 1981 Occurrence Date January 2, 1981 Identification of Occurrence During su.Mance testing the Contairrnent Spray high drywell pressure indicating switch IP-15C tripped at a value greater than that given in the Technical Specifica-tions, Table 3.1.1, iten E.1.

'Ihis event is cx:r.sidered to be a reportable occurrence as defined in the Technical Specifications, paragraph 6.9.2.b.l.

Conditions Prior to Occurrence The plant was operating at ste4' state power.

Shjor Plant Parameters:

Power: Reactor 1741 MWt Generator 602 FHe

, Flow: Recirculation 14.6 x 10 gpn Feedwater 6.42 x 10 lb/hr Description of Occurrence During performance of the "Contairment Spray Systen Autcrnatic Actuation Test" i (surveillance procedure 607.3.002), the IP-15C ' trip point was found to exceed the Technical Specifications desired setpoint. Testing of the four sensors "

yielded the following data:

Switch Designation Desired Setpoint As Found (psig) As Inft (psig)

IP-15A 120 psig 1.95 1.95 IP-15B 12 0 psig 1.95 1.95 IP-15C 120 psig 2.10 1.95 IP-15D 120 poig 1.99 1.99 Apparent Cause of Occurrence ,

'Ibe cause of the occurrence was instrunent repeatahility. 'Ihe switch was originally set at 1.94 psig and tripped at 2.10 psig. The range for repeatability is 2-3% of full range, which in the case of the IP-15 switenes is 0.2-0.3 psig. 'Ew difference i

of 0.16 psig between the setpoint and the actual trip pint clearly falls within the range of instrument repeats'-ility. .

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t Reportable Occurrence Page 2 Peport No. 50-219/81-01/3L Analysis of Occurrence

'Ihe Containment Spray Systen consists of two independent cooling loops, each of which is capable of renoving heat frcan the primary containment in the event of a loss of coolant accident. The Contairnent Spray Systen will be initiated upon receipt of both a high drywell pressure signal and a reactor low-low water level signal.

Although switch IP-15C would have tripped at a slightly higher pressure than the desired setpoint, its actuation only would have been delayed by a fraction of a second. Also, the reactor low-low level setpoint is not reached until almost 4 seconds after the setpoint for high drywell pressure is reached. Due to this and the fact that switch IP-15A for the sane instrument channel would have actuated at the required setpoint, the safety significance of the event is considered minimal.

Corrective Action Pressure switch IP-15C was reset to trip within the Technl cal Specifications limit of 2.0 psig (as shown in the "As Ieft" values in the Description of Occurrence). The drift problen of these snap-action switches is being investigated, along with possible setpoint changes to account for instn nent repeatability.

The PORC has also ramernnded replacement of the switches with a more qualified I:odel.

Failure Data Manufacturer: I'IT Barton Model: #288A pressure indicating switch Range: 0-10 psig I

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