PY-CEI-NRR-0729, Special Rept NP-39-01:on 870821,loose Part Detection Sys Declared Inoperable W/Less than Min Required Channels.Caused by Sys Being in Continuous Alarm W/O Confirmation of Loose Parts.Frequency Filters to Be Added

Special Rept NP-39-01:on 870821,loose Part Detection Sys Declared Inoperable W/Less than Min Required Channels.Caused by Sys Being in Continuous Alarm W/O Confirmation of Loose Parts.Frequency Filters to Be Added

ML20235M961
Person / Time
Site:	Perry
Issue date:	09/30/1987
From:	Edelman M CLEVELAND ELECTRIC ILLUMINATING CO.
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
NP-39-01, NP-39-1, PY-CEI-NRR-0729, PY-CEI-NRR-729, NUDOCS 8710060351
Download: ML20235M961 (2)

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[ - THE CLEVELAND ELECTRIC ILLUMIN ATING COMP ANY-i P.OJ BOX 5000 - CLEVELAND. OHIO 44101 .

TELEPHONE (216) 622 9800 - l ILLUMINATING DLDO. - 55 PUBLIC SQUARE  !

Semng The Best Iocation in the Nation

, j MURRAY R. EDELMAN sn vcs mesceNT NUCLE AR -

September 30, 1987 PY-CE1/NRR-0729 L" l ' Document Control Desk J U.S. Nuclear' Regulatory Commission

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l Washington, D.C. 20555 j Perry Nuclear Power Plant-Docket No. 50-440 Inoperable Loose-Part Detection System Instrumentation -

Special Report - NP-39-01

Dear Sir:

Attached is a Special Report concerning inoperable Loose-Part Detection System Instrumentation. This report satisfies the  !

conditions of Perry Technical Specifications 3.3.7.8 and 6.9.2.

Please feel free to contact me should you have any further questions.

Very truly ours, Murray R. Edel an Senior Vice President j Nuclear Group l MRE: cab l Attachment ec: T. Colburn K. Connaughton USNRC Region III Director, Office of Resource Management 7-l mat 8au BE%o i #

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l SPECIAL REPORT -- INOPERABLE LOOSE-PART DETECTION SYSTEM INSTRUMENTATION N P-39-01 On Au gus t 21, 1987 the Loose-Part Detection System (R63) was declared inoperable with less than the Minimum Required Channels required by Perry Technical Specifications 4.3.7.8. .This was due to the system being in continuous alarm without confirmation of any detected loose parts. The thirty day time limit to restore the Loose-Part Detection System channels to service was exceeded on September 20, 1987. . Actions required to restore the channels i to an operable status are continuing. All aspects of the Technical l Specification action statement were met. J This instrumentation is designed to continuously monitor for any indication of i Loose-Parts within the Nuclear Boiler System. Ten individual channels monitor l reactor vessel components with sensors physically mounted near expected 1 collection areas. Each channel consists of a detector, preamplifier, signal processing electronics which input to a tape recorder, audible speaker, a dB meter, control room annunciator, a spectrum' analyzer, x y plotter, a loose part- )

' locator' , and a pricter. I The cause of f ailure has been attributed to excessive flow noise being detected as valid input signals. The flow noise at high reactor power levels is  ;

erroneously detected by the sensors as an indication of 1cose parts causing the )

detection system to be in continuous alarm. To temporarily correct this design p roblem, flow noise and multiple harmonics will be. eliminated by the . addition of appropriate f requency filters to the signal processing electronics.

Currently, rework is being performed to change the bandwidth of the signal p rocessing electronics. Temporary electronic processing changes will be completed and the appropriate Technical Specification surveillance tests i performed to declare R63 operable. These temporary design changes should enable R63 to be returned to service prior to commercial operation of the Perry Plant. Engineering will continue to evaluate the R63 data and its performance in the interim. The long term design change may involve relocation of some accelerometers. This activity if required, will be completed during the first refueling outage.

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