05000219/LER-1981-011, Forwards LER 81-011/03L-0.Detailed Event Analysis Encl

Forwards LER 81-011/03L-0.Detailed Event Analysis Encl

ML20003E877
Person / Time
Site:	Oyster Creek
Issue date:	04/08/1981
From:	Finfrock I JERSEY CENTRAL POWER & LIGHT CO.
To:	Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20003E878	List: 05000219/LER-1981-011, Forwards LER 81-011/03L-0.Detailed Event Analysis Encl 05000219/LER-1981-011-03, /03L-0:on 810309,isolation Condenser Condensate Return Line Pipe Break Sensor IB11B2 Found to Trip at Value Greater than That Specified in Tech Specs.Caused by Instrument Repeatability.Replacement Recommended
References
NUDOCS 8104170426
Download: ML20003E877 (3)

LER-1981-011, Forwards LER 81-011/03L-0.Detailed Event Analysis Encl

Event date:
Report date:
2191981011R00 - NRC Website

text

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OYSTER CREEK NUCLEAR GENERATING STATION

&%.3"!'N4C?$7Lem s.v.m (609)693-6000 P.O. BOX 388

• FORKED RIVER e NEW JERSEY

• 08731 c-April 8, 1981 to E

Mr. Boyce H. Grier, Director Office of Inspection and Enforcsent h-]

s Pagion 1 2

i gP United States Nuclear Regulatory Comnission g* O 2 7 gOI A L 631 Park Avenue

{

King of Prussia, Pennsylvania 19406 Dreer

Dear Mr. Grier:

SL%IELT: Ofster Creek Nuclear Generating Station D aket No. 50-219 L.censee Event Peport Reportable Occurrence No. 50-219/81-ll/3L This letter forwards three copies of a Licensee Event Peport to report Peportable Occurrence No. 50-219/81-11/3L in cmpliance with paragraph 6.9.2.b.1 of the Technical Specifications.

Very truly yours, Ivan R. F roc, Jr.

Vice Pres ent - JCP&L Director - Oyster Creek IRF:dh Enclosures i

I cc: Director (40 copies)

Office of Inspection arel Enforcement United States Nuclear Pegulatory Ccmnission Washington, D.C.

20555 Director (3)

Office of Management Information and Program Control United States Nuclear Pegulatory Cm mission Washington, D. C. 20555 NRC Resident Inspector (1)

Oyster Creek Nuclear Generating Station 8104170 26

OYSTER CREEK NUCEAR GSTRATING STATICN Forked River, New Jersey 08731 Licensee Event Peport Reportable Occurrence No. 50-219/81-11/3L asport Date April 8, 1981 Occurrence Date March 9, 1981 Identification of Occurrem e During surveillance testing, the Isolation condenser isolation pipe break sensor IBilB2 tripped at a value greater than that specified in the Technical Stw Hica-tions Table 3.1.1, itan H.

This event is censidered to be a reportable occurrence as defined in the Technical Specificaticns, paragraph 6.9.2.b.l.

Conditiens Prior to Occurrence he plant was operating at steady state power.

Major Plant Paramere g:

Pcwer:

Feactor 1450 m t Generator 432 We Flow:

& L T h tien 14.2 x 104 gpn Feedwatel 4.58 x 10 lb/hr Description of Occurrence During the perfor:rance of the " Isolation Condenser Iselation Test and Calibra-tion" (Procedure 609.3.002), one of the isolation pipe break sensors for the condensate return line, IBilB2, tripped at a value greater than the limit of

<27.0" H O $ given in Table 3.1.1, iten H of the Technical Specifications. We 2

testing yielded the follcwing data:

Sensor "As Found" Desired "As Left" Desicnatien Value ("H2O AP)

Setpoint ("H 0 AP)

Value (H2O AP) 7 IB11A1 26.9

<27.0 26.9 IBllA2 25.0 727.0 26.9 in11ni 27.0 727.0 27.0 Tn11n2 28.5 127.0 26.3

Reportablo Occurrence Page 2 Report No. 50-219/81-11/3L Apparent Cause of Occurrence

'Ihe cause of the occurrence is attributed to instrument repeatability. 'Ihe total design error bandwidth, due to both instrument accuracy and calibration accuracy, is +2.08"H O AP (1.80 "l!go for instrument accuracy and 0.28" H O for 2

2 calibration accuracyT. Sensor IB1182 was last reset at 26.7 and tripped at 28.5, which is within the range of design repeatability.

Analysis of Occurrence The Isolation Condenser pipe break sensors are designed to provide protection in the event of a steam or condensate line pipe break outside the cor.tainment, and are located on pipe bends inside the containment. During normal operating conditions the Isolation Condensers are in a standby condition and the condensate return lines are isolated by normally closed isolation valves.

In the event of a pipe break outside the containment during system operation of the Isolation Condensers, the steam line pipe break sensor located in the same trip systen as sensor IBilB2 (sensor IB05B2) would have acb. lated within the specified limits to isolate condenser "B" in the required mmuwr. Based on the above, the safety significance of the occurrence is considered minimal.

Corrective Action

The switch was reset to trip within the limit of <27"H O AP as required by the 2

Technical Specifications (note the "As Left" values in the Description of Occurrence). Due to the frequency of setpoint drift problems associated with these snap-action type switches, the POBC has re u ne.nied replacement with a nore suitable qualified model. An evaluation of ITr Barton pressure switches is currently in progress, and possible setpoint changes are also being studied.

Failure Data Manufacturer - ITT Barton bbdel - #228A Indicating Pressure Switch Range 60" H O 2

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