05000219/LER-1981-062, Forwards LER 81-062/03L-0.Detailed Event Analysis Encl

Forwards LER 81-062/03L-0.Detailed Event Analysis Encl

ML20039G185
Person / Time
Site:	Oyster Creek
Issue date:	12/23/1981
From:	Pirooz H JERSEY CENTRAL POWER & LIGHT CO.
To:	Haynes R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20039G186	List: 05000219/LER-1981-062, Forwards LER 81-062/03L-0.Detailed Event Analysis Encl 05000219/LER-1981-062-03, /03L-0:on 811125,core Spray Hi Drywell Pressure Switch RV46C Tripped in Excess of Tech Spec Limit.Caused by Sensor Repeatability.Sensor Recalibr
References
NUDOCS 8201150364
Download: ML20039G185 (3)

LER-1981-062, Forwards LER 81-062/03L-0.Detailed Event Analysis Encl

Event date:
Report date:
2191981062R00 - NRC Website

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NUCLEAR GENERATING STATION C,YSTER CREEK FT M 1W (ff9) 693-1951 P O BOX 336

• FORKED PlVER

• NEV/ JERSEY

• 08731

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Decmber 23, 1981 s.

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Mr. Ronald Haynes, Director

. D Office of Inspection and Enforement BECEIVED Region I r, -

United States Nuclear Regulatory Comnission I

IM bb h 631 Park Avenue

. A N Nu t sum,ess:: :

"$N 8 King of Prussia, Pennsylvania 19406 4

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Dear Mr. Haynes:

g SURTELT: Oyster Creek Nuclear Generating Station Docket No. 50-219 Licensee Event Report Reportable Occurrence No. 50-219/81-62/3L This lettar forwards three copies of a Licensee Event Report to report Reportable Occurrence No. 50-219/81-62/3L in campliance with paragraph 6.9.2.b.1 of the Technical Specifications.

Very truly yours,

/

$dW[Y J. T. Carroll, Jr.

Acting Director O' ter Creek JIC:dh Enclosures U

cc: Director (40 copies)

Office of Inspection and Enforement United States Nuclear Regulatory Cmmission Washington, D.C.

20555 Director (3)

Office of Managment Information and Program Control United States Nuclear Regulatory Conmission Washington, D. C. 20555 NRC Resident Insp3ctor (1)

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

l 8201150364 811223 DR ADOCK 05000 g

i OYSTER CREEK NUCIEAR GENERATING STATION Forked River, New Jersey 08731 Licensee Event Report Reportable Occurrence No. 50-219/81-62/3L Report Date D e r 23, 1981 Occurrence Date Novenber 25, 1981 Identification of Occurrence t

During surveillance testing, the Core Spray High Drywell Pressure Sensor RV46C tripped at a value greater than the limit as given in 'Ibch. Spec., Table 3.1.1, iten D2.

This event is considered 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 steady state power.

Major Plant Parameters Power:

Reactor 1870 mt Generator 650 We 4

Flow:

Recirculation 15.0 x 10 #

6 Feedwater 7.11 x 10 lb/hr Description of Occurrmce On Wednesday, Novenber 25, while performing " Core Spray Instrunet Channel Calibration and Test" (Surveillance Procedure 610.3.005), high drivell pressure sensot RV46C tripped at a value greater than the Tech. Spec. limit of <2.0 psig.

The as-found trip set point was 2.3 psig.

l Apparent Cause of Occurrence The cause of the occurrence was attributed to instrument repeatability. The sensor was remlibrated to trip at 2.0, +0 or

.1 psig (the as-left setpoint was 1.9 psig). The long term repeatability of this sensor is approximately 3% of full scale (.3 psig).

...,. _. ~. -, _. _,,, - -, _

Reportable Occurrence Page 2 Report No. 50-219/81-62/3L Analysis of Occurrence The Core Spray Systen is made up of two independent loops, each of which provides heat re: oval frm the fuel assenblies in the event of a loss of coolant accident.

In order to initiate the core Spray Systen, a trip signal fran any one of the four (4) high drywell pressure sensors or any one of the four (4) reactor low.

low water level sensors must be received.

Although one (1) high drywell pressure sensor would have tripped at a higher pressure (2.3 psig) than the Tech. Spec. limit of 12.0 psig it would have operated, on increasing drywell pressure, with scoe delay.

The three (3) renaining high drywell pressure sensors would have tripped at or below the setpoint limit initiating the intended function of the Core Spray Systen, therefore, the safety significance of the occurrence is considered minimal.

Corrective Action

i The pressure sensor RV46C was recalibrated to trip within the Tech. Spec. limit 1 psig. An engineering study to investigate the problen of repeatability of 2

associated with this type of sensor has recamended the replacement of this type of sensor with qualified sensors of inproved accuracy. The replacanent is i

planned for a future refueling outage.

Failure Data Manufacturer: ITT Barton Model:

288A Pressure Indicating Switch Range:

0-10 psig I

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