ML20153C191

Supplemental Special Rept 1-SR-85-027:on 851030,during Performance of Surveillance Test Procedure 41ST-1DG01, Diesel Generator a Failed to Start.Caused by Faulty Fiber Optic Cable.Cable Reworked

ML20153C191
Person / Time
Site:	Palo Verde
Issue date:	01/23/1986
From:	Van Brunt E ARIZONA PUBLIC SERVICE CO. (FORMERLY ARIZONA NUCLEAR
To:	Martin J NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION V)
References
1-SR-85-027, 1-SR-85-27, ANPP-34792-EEVB, ANPP-34792-EEVP, NUDOCS 8602180448
Download: ML20153C191 (2)

Text

- ,

[ [0 Arizona Nuclear Power Project P.o Box 52034 e PHOENtX, ARIZONA 85072-2034

% g?j } 7 g,

)

J86 -

January 23cdEVhNb'f/98.07 ANPP-34792/

Mr. John B. Martin, Regional Administrator Office of Inspection and Enforcement U.S.' Nuclear Regulatory Commission Region V 1450 Maria Lane, Suite 210 Walnut Creek, CA 94596-5368

Subject:

Palo Verde Nuclear Generating Station (PVNGS)

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

Special Report - Diesel Generator Failure to Start During Surveillance Testing File: 86-020-404

Dear Mr. Martin:

Attached please find a revised Special Report (1-SR-85-027) prepared and submitted pursuant to Technical Specificatior.s 4.8.1.1.3 and 6.9.2. This report discusses a diesel generator start failure during Surveillance Testing.

If you have any questions, please contact me.

Very trulg yoy c c; L C . c. vQLLl J oLLL E. E. Van Brunt, Jr.

Executive Vice President Project Director EEVB/KLM/rw Attachments cc: R. P. Zimmerman (all w/a)

A. L. Hon E. A. Licitra A. C. Gehr INPO Records Center B602180448 860123

-PDR ADOCK 05000528 g PDR -

YI ff 97

Attachment to ANPP-T4792'-

PALO VERDE NUCLEAR GENERATING STATIION UNIT 1 DIESEL GENERATOR FAILED TO START DURING SURVEILLANCE TESTING Docket No. STN 50-528 License No. NPF-41 Supplement to Special Report 1-SR-85-027 At 0420 on October 30, 1985, Unit I was in Mode 4 when Diesel Generator "A" failed to start from the Control Room while performing Surveillance Test Procedure 41ST-1DG01 (Emergency Diesel Generator A Start and Load 4.8.1.1.2.a). - At 0450, an attempt was made to start the. diesel from the local control station, but it again failed to start.. The Unit 1 Shift Supervisor complied with Technical Specifications (T.S.) 3.8.1.1, ACTION a, by verifying the operability of the remaining A.C. power sources.

The cause of the unsuccessful start was a faulty fiber optic cable failing to actuate the 86S1Y relay (test mode starting relay). The failure of the 86S1Y relay to actuate simulated a nonessential trip to the - diesel engine control logic, with no actual trip signal present, and prevented test mode operation. Since nonessential trips are bypassed in an emergency condition, this fiber optic cable failure would not have prevented an emergency (accident) start. The opposite train diesel generator was proven operable in accordance with procedure 41ST-1ZZ02, satisfying T.S. 3.8.1.1., ACTION a. This was not logged as a valid test or failure in accordance with Regulatory Position C.2.e.(2) of Regulatory Guide 1.108, and a substantiating Engineering Evaluation Report was written.

The faulty fiber optic cable was reworked an'd Diesel Generator "A" l was declared OPERABLE at 0358 on October 31, 1985. Diesel Generator "A" had been unavailable for 23 hours2.662037e-4 days <br />0.00639 hours <br />3.80291e-5 weeks <br />8.7515e-6 months <br /> and 38 minutes.

Plant Change Request PCR-85-13-DG-058 was - initiated on November 1, 1985, to modify the fiber optic system to increase its reliability.

There have been two failures in the last 100 valid . tests. The current surveillance test interval is every 14 days and -is in conformance with Regulatory Position C.2.d.(2) of Regulatory Guide 1.108.

On January 4, 1986, the affected faulty fiber optic cable was replaced under Work Order #126181.