05000219/LER-1982-029, Forwards LER 82-029/01T-0.Detailed Event Analysis Encl

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Forwards LER 82-029/01T-0.Detailed Event Analysis Encl
ML20054H220
Person / Time
Site: Oyster Creek
Issue date: 06/14/1982
From: Fiedler P
GENERAL PUBLIC UTILITIES CORP.
To: Haynes R
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20054H221 List:
References
NUDOCS 8206230121
Download: ML20054H220 (3)


LER-2082-029, Forwards LER 82-029/01T-0.Detailed Event Analysis Encl
Event date:
Report date:
2192082029R00 - NRC Website

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GPU Nucteer f Q gf P.O. Box 388 Forked River, New Jersey 08731 609-693-6000 Writer's Direct Dial Number:

June 14, 1982 Mr. Ronald C. Haynes, Administrator Region i U.S. Nuclear Regulatory Commission 631 Park Avenue King of Prussia, PA 19406

Dear Mr. Haynes:

Subject:

Oyster Creek Nuclear Generating Station Docke t No. 50-219 Licensee Event Report Reportable Occurrence No. 50-219/82-29/01T This letter forwards three copies of a Licensee Event Report to report Reportable Occurrence No. 50-219/82-29/01T in compliance with paragraph 6.9.2.a.9 of the Technical Specifications.

Very truly yours, V

Peter B. Fiedler Vice President & Director Oyster Creek PBF:Ise Enc losure s c c: Director (40 copies) l Of fice of Inspection and Enforcement U.S. Nuclear Regulatory Cocunission Washington, D.C. 20555 Director (3)

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

Oyster Creek Nuclear Generating Station Forked River, NJ 08731 l

1 8206230121 820614

{DRADOCK 05000219 PDR GPU Nuclear is a part of the General Public Utilities System htV

OYSTER CREEK NUCLEAR CENERATING STATION Forked River, New Jersey 08731 Licensee Event Report Reportable Occurrence No. 50-219/82-29/01T Report Date June 14, 1982 Occurrence Date June 1 & 2, 1982 Identification of Occurrence All four (4) reactor high pressure scram switches were found to trip at values greater than the Technical Specification limiting safety system setting as specified in Section 2.3, Item 3.

This event is considered to be a reportable occurrence as defined in the Technical Specifications, paragraph 6.9.2.a.9.

Conditions Prior to Occurrence The plant was in steady state operatien.

Major Plant Parame t ers :

Power: Reactor 1276 MWt Generator 418 MWe Mode Switch Position - Run Description of Occurrence During surveillance testing of the reactor high pressure scram switches, all four (4) switches - RE03A, B, C, D - tripped at values greater than the limiting safety system setting. The data for the switches are shown below:

CORRECTED RPS TRIP TECH. SPEC. TECH. SPEC. AS FOUND AS LEFT SWITCH CHANNEL LIMIT (PSIC) LIMIT (PSIC)

  • VALUE (PSIG) VALUE (PSIC)

RE03A I <10 60 <1068 1075 1067 RE03B II 71060 71068 1075 1067 RE03C I 71060 71066 1070 1065 RE03D II {1060 ][1066 1073 1065

  • Corrected values are obtained by adding the appropriate head correction factors to the Tech. Spec. limit.

Licensee Event Report Page 2 Report able Occurrence No. 50-219/82-29/01T Apparent Cause of the Occurrence The apparent cause of the occurrence was instrument drif t. Switches RE03A and B were last reset at 1068 psig, which means a setpoint drif t of 7 psig for each s wit ch. Switches RE03C and D were last reset at 1066 psig, which means a setpoint drif t of 4 psig and 7 psig, respectively. The design accuracy of the switches is 17.5 psig, and the accuracy of the test gauge is 11.5 psig, for a total accuracy of 19.0 psig.

Analysis of Occurrence The setpoint for the reactor high pressure scram switches was chosen to assure that the reactor coolant system pressure safety limit and the fuel cladding integrity safety limit are never reached. These limits are 1375 psig and 1250 psig, respectively. The reactor high pressure switches were operable and would have initiated the required protective action at only a few pounds above the desired setpoint. Additionally, other protection devices would have acted to prevent exceedng the safety limit including neutron flux scram, anticipatory scrams, electromatic relief valves and safety valves; therefore, the significance of this event is minimized.

Corrective Action The switches were all reset to trip within the desired limits as part of the surveillance procedure. No further corrective action is anticipated unless the switches show undesirable behavior in future surveillance tests. The switches are scheduled for replacement during the Cycle 11 refueling outage with an improved model.

In the interim, the setpoint of the switches will be reviewed to determine whether a more conservative setting may be used.

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