ML17300B209

Special Rept 1-SR-88-001:on 880122,72 H Limit for High Range Noble Gas Monitor RU-142 Inoperability Exceeded.Caused by Defective Low Voltage Power Supply for RU-142 Microcomputer. Replacement Power Supply Installed & Calibr

ML17300B209
Person / Time
Site:	Palo Verde
Issue date:	02/16/1988
From:	Haynes J ARIZONA PUBLIC SERVICE CO. (FORMERLY ARIZONA NUCLEAR
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
1-SR-88-001, 1-SR-88-1, 192-00343-JGH-T, 192-343-JGH-T, NUDOCS 8802190123
Download: ML17300B209 (6)

Text

) 'CCELERATED DISTRIBUTION DEMONSTRATION SYSTEM j REGULATORY INFORMATION DISTRIBUTION SYSTEM (RIDS)

ACCESSION NBR:8802190123 DOC.DATE: 88/02/16 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-88-001:on 880122,72 h limit for hxgh range noble gas monitor inoperability exceeded.

DISTRIBUTION CODE: IE22D COPIES RECEIVED:LTR ENCL SIZE:

TITLE: 50.73 Licensee Event Report (LER), Incident Rpt, etc.

NOTES:Standardized plant. 05000528+

RECIPIENT COPIES RECIPIENT COPIES ID CODE/NAME PD5 LA LICITRA,E LTTR ENCL 1

1 1

1 ID PD5 PD DAVIS,M CODE/NAME LTTR ENCL 1

1 1

1 I

A INTERNAL: ACRS MICHELSON 1 1 ACRS MOELLER 2 2 AEOD/DOA 1 1 AEOD/DSP/NAS 1 1 AEOD/DSP/ROAB 2 2 AEOD/DS P/TPAB 1 1 ARM/DCTS/DAB 1 1 DEDRO 1 1 NRR/DEST/ADS 1 0 NRR/DEST/CEB 1 1 NRR/DEST/ELB 1 1 NRR/DEST/ICSB 1 1 NRR/DEST/MEB 1 1 NRR/DEST/MTB 1 1 NRR/DEST/PS B 1 1 NRR/DEST/RSB 1 1 NRR/DEST/SGB 1 1 NRR/DLPQ/HFB 1 1 NRR/DLPQ/QAB 1 1 NRR/DOEA/EAB 1 1 NRR/DREP/RAB 1 1 NRR/DREP/RPB 2 2 gSIB 1 1 NRR/PMAS/ILRB 1 1 G~XL& 02 1 1 RES TELFORD,J 1 1 RES/DE/EIB 1 1 RES/DRPS DIR 1 1 RGN5'ILE 01 1 1 EXTERNAL: EG&G GROH,M 5 5 FORD BLDG HOY,A 1 1 H ST LOBBY WARD 1 1 LPDR 1 1 NRC PDR 1 1 NSIC HARRIS,J 1 1 NSIC MAYS,G 1 1 NOTES: 1 1 A

TOTAL NUMBER OF COPIES REQUIRED: LTTR 48 ENCL 47

It1 t

Arizona Nuclear Power Project P.O. BOX 52034 ~ PHOENIX, ARIZONA85072-2034 192-00343-JGH/TDS/KCP February 16, 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-88-001 File: 88-020-404 Attached please find Special Report 1-SR-88-001 prepared and submitted pursuant to Technical Specification 3.3.3.8 ACTION 42 (b) and 6.9.2. This report discusses a radiation monitoring unit inoperable for greater than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.

If you have any questions, please contact T. D. Shriver, CotIIpliance Hanager at (602) 393-2521.

Very truly yours, J. G. Hayn s Vice President Nuclear Production JGH/TDS/KCP/kj Attachment cc: 0. t1. Dewichele (all w/a)

E. E. Van Brunt, Jr.

J. B. Hartin J. R. Ball E. A. Licitra A. C. Gehr INPO Records Center 8802gy 0123 880216 PDR- AgoCK Dt:D

PALO VERDE NUCLEAR GENERATING STATION Radiation Monitoring Unit Inoperable for Greater than 72 Hours License No. NPF-41 Docket No. STN 50-528 Special Report No. 1-SR-88-001 This Special Report is submitted in accordance with Technical Specification 3.3.3.8 ACTION 42 (b) and 6.9.2, for an event in which a high range noble gas monitor (RU-142) was inoperable for greater than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. The 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> limit for inoperability was exceeded at approximately 1801 tlST on January 22, 1988.

At approximately 1332 HST on January 18, 1988, with Palo Verde Unit 1 in Node 5 (COLD SHUTDOWN), the Condenser Vacuum Pump/Gland Seal Exhaust Low and High Range t1onitors were declared inoperable to permit surveillance testing.

Honitors RU-141 and RU-142 continuously monitor the condenser vacuum pump/gland seal exhaust for gaseous activity resulting from primary to secondary leakage. l1onitor RU-141 provides automatic initiation of filtration for the condenser vacuum pump/gland seal exhaust whenever the monitor registers a HIGH-HIGH alarm condition. t/onitors RU-141 and RU-142 work as a pair, with RU-141 as the low range monitor and RU-142 as the high range monitor. Normal configuration consists of RU-141 operating with RU-142 in standby. RU-141 and RU-142 are required to be operable in Nodes 1 through 4.

Since RU-141 and RU-142 >>ork in tandem, RU-142 must be declared inoperable if RU-141 is placed in an inoperable status.

During testing it was determined that the RU-142 check source would actuate locally but would not actuate from the associated Radiation flonitoring System (RHS) microcomputer. Corrective action to troubleshoot and re>>ork or replace components as required was initiated under an approved work document. At approximately 1801 HST on January 19, 1988 Palo Verde Unit 1 entered Node 4 (HOT SHUTDOWN), in accordance with the applicable limiting conditions for operations specified in T.S. 3.3.3.8. tlode 4 entry was permissible with the monitors inoperable because T.S. 3.3.3.8 ACTION (c) states that the provisions of T.S. 3.0.3 and 3.0.4 are not applicable.

Troubleshooting subsequently determined that the low voltage power supply for the RU-142 microcomputer, which provides power for remote actuation of the check source, was defective and required replacement. The replacement power supply was installed and calibrated in accordance with 36ST-9S(07, "Radiation thonitor Calibration Test for New Scope Process tlonitors." With the new power supply installed, the check source was verified to operate properly when actuated from the RHS microcomputer. A detector failure on RU-142 channel 3 was also identified and corrected by tightening a loose high voltage connector. Following completion of these activities, RU-142 was satisfactorily tested in accordance with 36ST-9Sg04, "Radiation l1onitoring

()uarterly Functional Test."

l1onitors RU-141 and RU-142 were returned to operable status at approximately 2214 HST on January 22, 1988, following satisfactory completion of the above activities and performance of 75ST-9ZZ07, "Effluent t1onitoring System Daily Surveillance Testing." The duration of this event was approximately 76 hours8.796296e-4 days <br />0.0211 hours <br />1.256614e-4 weeks <br />2.8918e-5 months <br />.

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