ML19309C299

Forwards LER 80-010/03L-0

ML19309C299
Person / Time
Site:	Fort Saint Vrain
Issue date:	04/02/1980
From:	Warembourg D PUBLIC SERVICE CO. OF COLORADO
To:	Seyfrit K NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION IV)
Shared Package
ML19309C300	List: ML19309C299 ML19309C304
References
P-80068, NUDOCS 8004080422
Download: ML19309C299 (4)

Text

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pubuc SeMee Company & Cdesde

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! 16805 Weld County Road 191/2, Platteville, Colorado 80651 x ;

April 2,1980 Fort St. Vrain

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Unit No. 1 P-80068 Mr. Karl V. Seyfrit, Director Nuclear Regulatory Commission Region IV Office of Inspection and Enforcement

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611 Ryan Plaza Drive

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Suite 1000 Arlington, Texas 76012 Re ference: Facility Operating License l

No. DPR-34 Docket No. 50-267

Dear Mr. Seyfrit:

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Enclosed please find a copy of Reportable Occurrence Report No. 50-267/

80-10, Final, submitted per the requirements of Technical Specification AC 7.5.2(b)2.

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Also, please find enclosed one copy of the Licensee Event Report for Reportable Occurrence Report No. 50-267/80-10.

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Very truly yours, W

Don Warembourg Manager, Nuclear Production DW/cis Enclosure l cc: Director, MIPC l

3009 s,

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REPORT DATE: Ap ril 2, 1980 REPORTABLE OCCURPINCE 80-10 ISSUE O e

OCCURRENCE DATE: March 3, 1980 Page 1 of 3 FORT ST. VRAIN NUCLEAR GENERATING STATION PUBLIC SERVICE COMPANY OF COLORADO 16805 WELD COUNTY ROAD 19 1/2 PLATTEVILLE, COLORADO 80651 REPORT No. 50-267/80-10/03-L-0 Final IDENTIFICATION OF OCCURRENCE :

On March 3,1980, scheduled surveillance testing revealed that "A" emergency diesel generator would not load properly. This is being reported as a degraded mode of LCO 4.6.l(d) per Fort St. Vrain Technical Specification AC 7.5.2(b)2.

EVENT DESCRIPTION:

On March 3,1980, while operating at 10% thermal power, surveillance testing revealed that "A" emergency diesel generator would not load properly for the scheduled weekly 50% load test.

This weekly 50% load test consists of starting the emergency diesel generator, paralleling with the system, and then loading the diesel generator to greater than 700 KW or 50% of the load capacity. Then the diesel generator is run for at least 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> to ensure operability.

The diesel generator governor control was erratic and resulted in excessive load fluctuation with the diesel generator paralleled to the system. The electrical maintenance personnel found the problem in the governor speed sensing circuit. It is believed that the diesel generator would have oper-ated independently, which would be the mode of operation if the plant had lost normal electrical power. The problem in the speed sensing curcuit reduced the response time of the governor so that it could not balance the load with the system.

"B" emergency diesel generator was operable and available during this period.

CAUSE

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DESCRIPTION:

The "A" emergency diesel generator governor developed a problem in the speed sensing circuit which decreased the speed control response of the gove rnor.

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f' REPORTABLE OCCURRENCE 80-10 .

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Pa ge 2 of 3 '

4 CORRECTIVE o

ACTION:

The faulty governor assembly was removed and sent to the' manufacturer -for ,

repair and calibration. .

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, A spare unit was installed and "A" emergency- diesel generator was successfully

retested.

j No further corrective action is anticipated or required.

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' REPORTABLE OCCURRENCE 80-10 ISSLT 0 Page 3 of 3

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Prepared By: [Ub d^ 'bl{. -

Asa B. Reed

, Technical Services Technician

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b Reviewed By: c, d J. W. Gp im TechnictL Services

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Supervisor Reviewed 3y: Ob Frank M. Mathie Operations Manager '

F Approved By: ,

Ma o wMum Dori Warembourg /[

Manager, Nuclear ProductMn r

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