ML19340D723

Forwards LER 80-056/03L-0

ML19340D723
Person / Time
Site:	Oyster Creek
Issue date:	12/23/1980
From:	Finfrock I JERSEY CENTRAL POWER & LIGHT CO.
To:	Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML19340D724	List: ML19340D723 ML19340D726
References
NUDOCS 8101050223
Download: ML19340D723 (3)

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l OYSTER CREEK NUCLEAR GENERATING STATION FL*3 ~1:WJ.

g, c..n. .i

. 'A .u. ,n; atg (609) 693-1951 P.O. BOX 388

• FORKED RIVER

• NEW JERSEY

• 08731 c..n u, . s,sn 4.-

Decenber 23, 1980 Mr. Boyce H. Grier, Director '

Office of Inspection and Enforcenent ,l Region I '

United States Nuclear Regulatory Conmission ..

641 Park Avenue @g;.

King of Prussia, Pennsylvania 19406 'g" __

Dear Mr. Grier:

N

• to ..

SUBJECT:

Oyster Creek Nuclear Generating Station Docket No. 50-219 Licensee Event Peport Reportable Occurrence No. 50-219/80-56/3L This letter forwards three copies of a Licensee Event Report to report Reprtable Occurrence No. 50-219/80-56/3L in canpliance with paragraph 6.9.2.b.1 of the Technical Specifications.

Very truly yours,

/ $&l.MY -

. van R. Finfrock, r y Vice President Ge.

IRE':dh Enclosures cc: Mr. John G. Davis, Acting Director (40 copies)

Office of Inspection and Enforcenent United States Nuclear Regulatory Ccmnission Washington, D.C. 20555 t

Mr. William G. Mcdonald, Director (3 copies)

Office of Managenent Infonnation and Program Control i

United States Nuclear Regulatory Camtission Washington, D.C. 20555

'8'101050 W g

OYSTER CREEK NUCLEAR GENEPATING STATION Forked River, New Jersey 08731 Licensee Event Report Reportable Occurrence No. 50-219/80-56/3L Report Date December 23, 1980 Occurrence Date Decmber 4,1980 Identification of Occurrence During surveillance testing, the Fhin Steam Line high flow indicator switcMs RE-22C and RE-22G tripped at values greater than the desired setpoint as given in the Technical Specifications, Table 3.1.1, itcm B.2.

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 pcuer.

Major Plant Paraneters:

Power: Reactor 1817 FMt Generator 627 MWe Flow: Recirculation 15.2 x 10j gpn Feedwater 6.73 x 10 lb/hr Description of Occurrence On Thursday, Deccrrber 4, durig performance of the "High Flow in the Main Steam l Line Test and Calibration" (Surveillance Procedure 619.3.005), high flow indicator i switches RE-22C and RE-22G tripped at values greater than the Technical Specifica-l tion limit of <97.5 psig. The testing yielded the followig data:

Switch Designation Desired Setpoint (PSIG) As Found(PSIG) As Left(PSIG)

RE-22A <97.5 91.5 91.5

RE-22B 597.5 97.0 91.5 RE-22C <97.5 98.5 93.0 RE-22D 797.5 96.5 92.5 RE-22E 797.3 96.5 93.0 RE-22F 797.5 97.0 92.0 i

RE-22G 797.5 98.5 93.0 l RE-22H 597.5 96.5 92.5 l

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i Reportable Occurrence Page 2 Report No. 50-219/80-56/3L i

Apoarent Cause of Occurrence n e cause :.f the occurrence was attributed to instrument repeatability. The switches are set to trip at 92.5+ 1 psig and the long-term repeatability of the instrunents is approxunately 4-6 psig (2-3% of full range) . It is possible for the instrument to trip at a value as high as 99.5 psig and still operate within the design accuracy, yet exceed the Technical Specification limit of 97.5 psig.

, , Analysis of Occurrence ne Main Steam Line will isolate due to a line break as sensed by either a high ter:perature or a high flow condition.

Each train steam line contains four (4) high flow sensors, which are part of the logic systen which will initiate closure of the main steam isolation valves (MSIV). The logic systen contains 2 channels, and a signal fran both channels is required to initiate MSIV closure. In addition, each channel containing four (4) sensors is further divided into 2 circuits.

The safety significance of the occurrence is considered minirral. With the existing logic systen, there is only a tarporary loss of redundancy in one of the channels due to the non-conservatism of switches RE-22C and RE-22G. Although switches RE-22C and RE-22G are located within the same channel, switches RE-22D and RE-22H would have actuated at the desired setpoint and would have supplied the signal necessary fran that channel to initiate the MSIV closure.

l Corrective Action Pressure switch RE-22C was reset to trip within 92.5+ 1 psig, as were the 1

renalning switches which had tripped within the desired range (note the "As

Left" values in the Description of Occurrence section) . Sen mr RE-22G at first

! could not be adjusted to trip at the desired level, due to a problen with the

' microswitch. The microswitch was replaced and the instrument then operated properly and was reset to trip at the desired level. After consideration of the

! frequency of occurrence of set point drift associated with ITT Barton differential j pressure indicating switches with snap-action switches, the POPC reww.raed replacanent of these devices with a I:cre suitable qualified tredel.

I Failure Data Manufacturer: ITr Barton ,,

Model: 228A pressure indicating switch Rarge: 0-200 psig 1 l I

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