ML17304A776

Special Rept 1-SR-88-008:on 881113,Tech Specs Violated. Caused by Loose Part Detection Channel Being Inoperable for More than 30 Days Due to Problems W/False Alarms.Sys Will Be Monitored Once Per 24 H & Investigation Initiated

ML17304A776
Person / Time
Site:	Palo Verde
Issue date:	11/22/1988
From:	Haynes J ARIZONA PUBLIC SERVICE CO. (FORMERLY ARIZONA NUCLEAR
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
1-SR-88-008, 1-SR-88-8, 192-00433-JGH-T, 192-433-JGH-T, NUDOCS 8811290358
Download: ML17304A776 (6)

Text

.'C CI:LERATED DISIGBUTION DEMONST1LON SYSTEM REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)

ACCESSION NBR:8811290358 DOC DATE: 88/11/22 NOTARIZED- NO DOCKET

. FACIL:STN-50-528. Palo Verde Nuclear Station, Unit 1, Arizona Publi 05000528 ~

AUTH. NAME AUTHOR AFFILIATION HAYNES,J.G. Arizona Nuclear Power Project (formerly Arizona Public Serv RECIP.NAME RECIPIENT AFFILIATION Document Control Branch (Document Control Desk)

SUBJECT:

. Special Rept 1-SR-88-008:on 881113,loose part detection channel inoperable for more than 30 days.

DISTRIBUTION CODE IE22D COPIES RECEIVED:LTR ENCL SIZE:

TITLE: 50.73 Licensee Event Report (LER), Inci ent Rp , etc.

NOTES:Standardized plant. 05000528 ~

S' RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR ENCL PD5 LA 1 1 PD5 PD 1 1 CHAN,T 1 1 ~ DAVIS,M 1 1 INTERNAL: ACRS MICHELSON 1 1 ACRS MOELLER 2 2 ACRS WYLIE 1 1 AEOD/DOA 1 1 AEOD/DSP/TPAB 1 1 ARM/DCTS/DAB 1 1 DEDRO 1 1 NRR/DEST/ADS 7E 1 0 NRR/DEST/CEB 8H. 1 1 NRR/DEST/ESB 8D 1 1 NRR/DEST/ICSB 7 1 1, NRR/DEST/MEB 9H 1 1 NRR/DEST/MTB 9H 1. 1 NRR/DEST/PSB 8D ~ 1 1 NRR/DEST/RSB 8E 1 1. NRR/DEST/SGB 8D 1 1

'NRR/DLPQ/HFB 10 1 1 NRR/DLPQ/QAB 10 1 1 NRR/DOEA/EAB 11 1 1' NRR/DREP/RAB 10 1 1 NRR/DREP/RPB 10 2 NRR/DRIS/SIB 9A 1 1 NUDOCS-ABSTRACT 1 1 02 1 1 RES/DSIR/EIB 1 1 RES/DSR/PRAB 1 1 RGN5'ILE 01 1 ~

1 EXTERNAL: EG&G WILLIAMS,S 4 4 FORD BLDG HOY,A 1 1 H ST LOBBY WARD 1 1 LPDR 1 1 NRC PDR .1 1 NSIC HARRIS,J 1 NSIC MAYS,G 1 1 NOTES 1 1 NCTE K ALL RZDS" RECIPIENTS: D 1

PXEASE HELP US TO REDUCE %ASTE! QMIRCT XHE DOCUNEÃZ COEQUAL DESK, D HXM Pl-37 (EXT. 20079) TO XXaTMZNATFi HX3R NAME HKH DISTRIBUTION ZiZSKS KR DOCEKMXS YOU D0IN'T NEEDf 8',

TOTAL NUMBER OF COPIES REQUIRED:, LTTR 44 ENCL 43

Arizona Nuclear Power Project P.O. BOX 52034 ~ PHOENIX, ARIZONA85072-2034 192-00433-JGH/TDS/DAJ November 22, 1988 U. S. Nuclear Regulatory Commission NRC Document Control Desk Washington, D.C.. 20555

Subject:

Palo Verde Nuclear Generating Station (PVNGS)

Unit 1 Docket No. STN 50-528 (License No. NPF-41)

Special Report 1-SR-88-008 File: 88-020-404 Attached please find Special Report 1-SR-88-008 prepared and submitted pursuant to Technical Specifications 3.3 3.7, ACTION ".a" and 6.9.2. This report discusses an inoperable Loose Parts Detection System Channel.

If you (602) 393-2521.'ery have any questions, please contact T. D. Shriver, Compliance Manager at trul yours, J. G. Hay es Vice President Nuclear Production JGH/TDS/DAJ/kj Attachment cc: D. B. Karner (all w/a)

E. E. Van Brunt, Jr.

J. B. Martin T. J. Polich M. J. Davis A. C. Gehr INPO Records Center Qpg,Z PDR i ~8 SP$ $ 2"7 i l K 0~00 POC

I

'o Verde Nuclear Generating St n Unit I Loose Part Detection Instrumentation License No. NPF-41 Docket No. 50-528 Special Report No. I-SR-88-008 This Special Report is being submitted pursuant to Technical Specification 3.3.3.7, ACTION "a" and Technical Specification 6.9.2 addressing a Loose Part Detection channel being inoperable for more than thirty (30) days. The 30 day period for returning the channel to an operable status was exceeded at approximately 2145 MST on November 13, 1988 The Loose Part Detection System consists of eight (8) channels. Each channe1 consists of a piezoelectric crystal motion sensor and associated amplification, indication, and recording circuitry. The sensors are positioned in the following locations: two (2) mounted on the Reactor Vessel upper head, two (2) mounted on the Reactor Vessel lower incore nozzle, and one (I) on each of the two (2) Steam Generators'nlet and outlet nozzles. The piezoelectric sens'ors'etect the loose parts using acoustic signals which are generated when loose parts impact a Reactor Coolant System component or structure. Signals in excess of the alarm setpoint will result in an alarm The alarms are the "latch-on" type, i.e., the alarm will remain on 'ondition.

when the system returns to normal and will not clear until the alarm is manually reset. There is one alarm indicator in the Control Room for the eight channels such that a "latch on" alarm effectively renders the Control.

Room alarm indication inoperable for the remaining channels upon receipt of an alarm condition. In addition 'to the alarm in the Control Room, a tape recorder will start. There. are two tape recorders; four system channels input into one tape recorder.

On October 14, 1988 Palo Verde Unit I was in Mode I (POWER OPERATION) at approximately 100 percent power when Loose Part Detection System Channel 5 (Steam Generator 1A inlet) was declared inoperable due to repeated spurious alarms. An approved work document was initiated to troubleshoot the cause of the spurious alarms. As a result of the troubleshooting, it was determined that no component malfunctions existed and that the alarm setpoint being near background noise levels resulted in the spurious alarms.

In order to enable the reflash capability for the visual alarm indication in the Control Room and the automatic recording feature for the other channels sharing the recorder utilized by Channel 5, the Channel 5 setpoint has been raised to prevent false alarms. This renders Channel 5 inoperable; however, it remains functional. During the period of Channel 5 inoperability, Operations Department personnel will audibly monitor the, Loose Part Detection System at least once per twenty-four hours. Additionally, ANPP Vibration Group and Engineering personnel will monitor the inoperable channel once per week during the period of .inoperability.

An engineering evaluation has been initiated to investigate the problem with the Loose Part Detection System Channel 5 and develop a solution. Based upon the engineering evaluatin, appropriate actions will be taken to return the system to an operable status. A supplement to this report will be submitted to describe the corrective actions and schedule for restoring the system to service.

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