05000219/LER-1983-008, Forwards LER 83-008/03L-0.Detailed Event Analysis Encl

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Forwards LER 83-008/03L-0.Detailed Event Analysis Encl
ML20073P200
Person / Time
Site: Oyster Creek
Issue date: 04/12/1983
From: Fiedler P
GENERAL PUBLIC UTILITIES CORP.
To:
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20073P202 List:
References
NUDOCS 8304250063
Download: ML20073P200 (4)
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LER-1983-008, Forwards LER 83-008/03L-0.Detailed Event Analysis Encl
Event date:
Report date:
2191983008R00 - NRC Website
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text

l' GPU Nuclear Q

g7 P.O. Box 388 Forked River, New Jersey 08731 609-693-6000 Writer's Direct Dial Number:

April 12, 1983 Regional Administrator Region I U.S. Nuclear Regulatory Commission 631 Park Avenue King of Prussia, PA 19406

Dear Sir:

Subject: Oyster Creek Nuclear Generating Station Docket No. 50-219 Licensee Event Report Reportable Occurrence No. 50-219/8 3-08/ 03L This letter forwards three copies of a Licensee Event Report (LER) to report Reportable Occurrence No. 50-219/83-08/03L in compliance with paragraph 6.9.2.b.3 of the Technical Specifications.

Very truly yours, f$

th Peter B. Fiedler Vice President and Director Oyster Creek PBF:jal Enclosure s cc: Director (40 copies)

Of fice of Inspection and Enforcement U.S. Nuclear Regulatory Commission Washington, D.C.

20555 Dire c tor (3)

Of fice of Management Information and Program Control U.S. Nuclear Regulatory Commission Washington, D.C.

20555 NRC Resident Inspector Oyster Creek Nuclear Generating Station Forked River, NJ 08731 8304250063 830412 PDR ADOCK 05000219 S

PDR GPU Nuclear is a part of the General Pubhc Utihtees System gfe N

L_

f OYSTER CREF.K NUCLEAR GENERATING STATION-Forked River, New Jersey 08731 Licensee Event Report Reportable ' Occurrerce No. 50-219/83-08/03L T

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Report Date j

April 12, 1983 Decurrence Date March 14, 1983 Identification of Occurrence Core spray booster pump NZO3A was found to be inoperable when given a manual start. signal.

i This event is considered to be a reportable occurrence as defined in the Technical Specifications, paragraph 6.9.2.b.3.

Conditions Prior to Occurrence The plant was shutdown with the mode switch locked in the REFUEL position.

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Reactor Coolant Temperature:

100 F Description of Occurrence 4

On March 1,1983 preventive maintenance (PM) was performed on core spray booster pump NZO3A breaker. The electrician performing the PM noticed that the undervoltage trip coil (which is part of the static time delay undervoltage tripping device) appeared to be degraded, with the coil wrapping off and' the leads unsupported. A spare coil, believed to be the correct replacement part and one which had been QA processed for use, was obtained to perform corrective maintenance. The coil was bench test ed and installed in core spray booster pump NZO3A breaker as a replacement for the degraded coil.

The breaker remained tagged out of service until additional repairs and checks were made. The breaker was tested successfully three (3) times before it was turned over to Operations and declared operable on March 14, 1983.

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Licensee Event Report Page 2

.Reportabl ' Occurrence No. 50-219/83-08/03L On March 14, 1983, at approximately 1845 hours0.0214 days <br />0.513 hours <br />0.00305 weeks <br />7.020225e-4 months <br />, core spray booster pump NZO3A was operated for 20 minutes (during core spray flushing procedure) for the first time since the breaker PM.

Af ter a brief shutdown, the pump was given a manual start signal but failed to restart._ An electrician was sent to 1

investigate the problem.' It was determined that the static time delay
undervoltage tripping system had failed. This system consists of an undervoltage trip coil assembly (coil replaced March 1,1983) and a static i

time delay unit. The static time delay unit was replaced with a unit from an identical breaker which was not in service. The coil assembly was replaced with a spare unit from QA storage.. This spare was confirmed to be correct by part verification, procurement documentation and resistance tests.

Further investigation determined that the coil, initially installed-on March 1,1983, was an incorrect replacement part (slightly differing part number). That coil had a resistance of 132 ORMS instead of 1830 OHMS as called for by General Electric for the correct part. Af ter the correct parts were installed, the breaker and pump were tested satisfactorily and declared operable at approximately 0054 hours6.25e-4 days <br />0.015 hours <br />8.928571e-5 weeks <br />2.0547e-5 months <br /> on March 15, 1983.

Apparent Cause of Occurrence The cause of this occurrence was attributed to the installation of an incorrect replacement part which led to excessive current draw and to the i

subsequent failure of the static time delay undervoltage tripping device.

- Several personnel errors contributed to the incorrect part being delivered, j

inspected and released for use in Core Spray System maintenance. Although the right part (6275081G59) was ordered, the wrong part (6275081G5) was delivered and certified as the right part (6275081G59) by the vendor. It was then inspected and released by plant QA for use.

Analysis of Occurrence The Core Spray System utilizes two redundant loops with four (4) pumps per loop (2 main and 2 booster pumps) to provide a supply of low pressure _ coolant in case of a pipe break in the reactor primary system.

Since the plant was shutdown with the mode switch locked in REFUEL and the reactor cavity was flooded to the 117 foot level, Technical Specifications do not require the Core Spray System to be operable. However, as Technical Specifications allow 5

work to be performed on the reactor or its connected systems which could i

possibly result in a loss of coolant inventory, the redundant core enray loop l

was available to deliver rated core spray flow, if needed. The safety significance, therefore, is considered minimal.

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Licensee Event Report Page 3 Reportable Occurrence No. 50-219/83-08/03L

Corrective Action

Immediate corrective action was to replace the defective static time delay unit and the undervoltage trip coil unit. The breaker and pump were then tested satisfactorily and declared operable at approximately 0054 hours6.25e-4 days <br />0.015 hours <br />8.928571e-5 weeks <br />2.0547e-5 months <br /> on March 15, 1983. An evaluation will be performed to determine if additional controls are required in order to preclude recurrence of this problem. As the supplier's Certificate of Conformance was in error, a notification will be forwarded to that company and a comment will be made on the Supplier Classification List to provide additional scrutiny of parts procurement.

Failure Data 1.

General Electric UV Trip Coil Part No. - 6275081G59 2.

Gene ral Electric Shunt Trip Coil Part No. - 6275081G5 3.

General Electric Static Time Delay Unit Part No. - 177L316G12 Note:. Item 2 (cause of failure) was supplied by RESCO l

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