ML17300A867

Special Rept 2-SR-87-013:on 870421,process Monitor RU-1 Inoperable for More than 72 H Due to Frequent Failure Alarms.Caused by Voltage Spikes on Grounding Sys.Mod Initiated to Replace Moving Filter Assembly W/Fixed Filter

ML17300A867
Person / Time
Site:	Palo Verde
Issue date:	05/18/1987
From:	Haynes J ARIZONA PUBLIC SERVICE CO. (FORMERLY ARIZONA NUCLEAR
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
192-00211-JGH-T, 192-211-JGH-T, 2-SR-87-013, 2-SR-87-13, NUDOCS 8705280087
Download: ML17300A867 (3)

Text

REGULATORY NFORMA'I ION D ISTR IBUTION S M ( R IDS )

ACCESS~ON NBR: 8705280087 DOC. DA'TE'r/05/1 8 NOTARIZED: NO DOCVET FACIL: STN-50-529 Palo Verde Nuclear Station> Unit 2> Arizona Pub I i 050005~9 AUTH. NAME AUTHOR AFFILIATION HAYNEBp J. Q. Arizona Nuclear Poucr Prospect < formerly Ari zona Public Serv RECIP. NAME RECIPIENT AFFILIA1l>>N Document Control 8< anch (Document Control Des')

SUBJECT:

Special Rept 2-SR-87-013: on 870':21> process monitor RU-5 inoperable For more than 72 h doe to Frequent failure alarms. Caused bg voltage spiKes on grounding sos. Mod initiated to replace moving f il+er assembly tu/Fi>ed filter.

DISTRIBUTION CODE IE22D COPIES RFCE<VEu: LTR Q ENCL Q SIZE:

TITLE: 50. 73 Licensee Event Repor+ <LFH) Incident Rpt> e+c.

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NOTES: Standardized plant. M. Davis> N~R: 1Cg. 05000529 RECIPIENT COPIES REC I P I EN T COP IE S ID CODE/NAME LTTR ENCL ID CODE/NAME LTTR &t TCL PD5 LA 1 1 PD5 PD 1 LICITRA> E 1 1 D VIS>M 5 INTERNAL: ACRS MICHELSON 1 f ACRB MOELLER >p AEOD/DOA 1 5. ALOD/DSP/ROAB 2 2 AEOD/DBP/TPAB 1 D-nRO 1 5.

NRR/DEBT/ADE 1 0 NHR/DEBT/ADS 1 0 NRR/DEBT/CEB 1 t!>R/DEBT/ELB 1 NRR/DEBT/ICBB 1 f t!<R/DEBT/hEO 5.

NRR/DEBT/MTB 1 1 t!HR/DEBT/PSB 1 1 NRR/DEBT/RSB 1 1 VnR/DEBT/SQB 1 NRR/DLPG/HFB 1 NHR/DLPG/GAB 1 l NRR/DOEA/EAB f i<!HR/DREP/R*B 1 NRR/DREP/RPB 2 2 ." R/3 J'.IQB/ ILRB 1 NRR/PMAS/PTSB 1 ~8= FM~

FI 02 01 1 5 RES DEPY GI 1 1 RCN5 LE 1 1 EXTERNAL: EQSG GROHp M 5 H ST LOBBY WARD 1 1 LPDR 1 1 KRC PDR 1 1 NSIC HARRIS J 1 1 t!SIC NAYS> 0 1 NOTES' 1 1 TOTAL NUMBER OF COPIES REQUIRED: LT/R O'NCL 42

Arizona Nuclear Power Project P.o. BOX 52034 ~ PHOENIX, ARIZONA85072-2034 192-00211-JGH/TRB/JEM May 18, 1987 NRC Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C. 20555

Subject:

Palo Verde Nuclear Generating Station Unit 2 Docket No. STN 50-529 (License NPF-51)

Special Report 2-SR-87-013 File: 87-020-404

Dear Sirs:

Attached please find a Special Report 2-SR-87-013 prepared and submitted pursuant to Technical Specifications 3.3.3.1 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 Tom Bradish, Compliance Supervisor at (602) 932-5300, Ext. 6936.

Very tr y yours, J. G. Haynes Vice President Nuclear Production JGH/TRB/JEM/cld Attachment cc: 0. M. DeMichele (all w/a)

E. E. Van Brunt, Jr.

J. B. Martin R. P. Zimmerman R. C. Sorenson E. A. Licitra A. C. Gehr INPO Records Center 8705280087 870518 PDR ADOCK 05000529 8 PDR

PALO VERDE NUCLEAR GENERATING STATION Radiation Monitoring Unit Inoperable for Greater Than 72 Hours License No. NPF-51 Docket No. STN 50-529 Special Report No. 2-SR-87-013 This Special Report is being submitted pursuant to Technical Specification 3.3.3.1 ACTION 27 and Technical Specification 6.9.2 to report an event in which a process monitor, Containment Building Atmosphere RU-l, 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 operability was exceeded at approximately 0700 MST on April 24, 1987. Pursuant to Technical Specifiction 3.3.3.1 ACTION 27 a moveable air monitor (RU-53) was placed in line to monitor the Containment Building atmosphere.

At approximately 0700 MST on April 21, 1987 Palo Verde Unit 2 was in Mode 1 (POlKR OPERATION) when RU-1 was declared inoperable due to frequent Filter Failure Alarms.

Troubleshooting and repair, in accordance with an approved work control document, resulted in the replacement of the filter mechanism and a transistor logic board.

However, this action did not alleviate the alarms. Additional troubleshooting revealed voltage spikes on the grounding system. The voltage spikes were traced to the sample pump motor starter circuit. The motor starter circuit was replaced with a new circuit.

The new starter circuit reduced the voltage spikes but did not alleviate the filter alarms. Troubleshooting is continuing in an effort to identify and correct the voltage spike problems.

Due to the continued intermittent filter failure alarms a modification to RU-1 will be implemented during the week of May 18, 1987. This modification will replace the moving filter assembly with a fixed filter. This is expected to eliminate the filter failure alarms. It is expected that RU-1 should be returned to operability by June 1, 1987. A schedule for implementation of this modification on other similar monitors will be developed.

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