ML20006A497

Special Rept:On 891222,valid Failure of Div 1 Diesel Generator Occurred During Div 1 Diesel Generator Start. Caused by Degraged Lubricant on Latch Mechanism Pivot Point Due to Aging.Work Order Initiated to Svc Breaker

ML20006A497
Person / Time
Site:	Perry
Issue date:	01/19/1990
From:	Kaplan A CLEVELAND ELECTRIC ILLUMINATING CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
PY-CEI-NRR-1120, NUDOCS 9001290034
Download: ML20006A497 (3)

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, ' o ,o THE CLEVELAND ELECTRIC ILLUMINATING COMPANY P.O. BOX 97 E PERRY, OHIO 44001 S TELEPHONE (216) 266 3737 3 ADDREBS10 CENTER ROAD FROM CLEVELAND: 4741260 3 TELEX; 241699 ANSWERBACK: CEIPRYO Al Kaplan Serving The Best location in the Nation PERRY NUCLEAR POWER PLANT vet estram i NUCLE AR GROLW p<

January 19, 1990 PY-CEI/NRR-1120L l

Document Control Desk U.S. Neclear Regulatory Commission Washington, D.C. 20555 Perry Nuclear Power Plant Docket No. 50-440 '

Special Report -

Valid Test Failure ,

Division 1 Diesel Generator

Dear Sir:

Attached is a Special Report concerning a valid test failure of the Unit 1 Division 1 Diesel Generator. This report satisfies the conditions of i Technical Specifications 4.8.1.1.2 and 6.9.2.

Please feel free to contact me if you have any further questions.

Very truly yours, i .

A. Kaplan Vice President Nuclear Group AK/nje Attachment cc T. Colburn P. Hiland L. Hiller (Office of Resource Management)

USNRC Region III, Regional Administrator 9001290034 900119 PDR ADOCK 05000440 s PDC

$$$A

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l c o Attachment PY-CEI/NRR-1120L Page 1 of 2 t

SPBCIAL REPORT Unit 1 Division 1 Diesel Generator Valid Failure On December 22, 1989, a valid failure of the Division 1 Diesel Generator occurred while performing the Division 1 Diesel Generator Start and Load Surveillance Test. This is a valid test and failure in accordance with Regulatory Guide, R.G. 1.108 C.2.e.5. This is the third valid failure in 73 total valid tests to occur on the Unit 1 Division 1 Diesel Generator and the first failure in the last twenty valid tests.

On December 22, 1989, a valid failure of the Division 1 Standby Diesel Generator occurred while performing the Start and Load surveillance test as part of Technical Specification Action statement required due to the Division 3 Diesel Generator being declared inoperable. The engine start was normal with the acceleration and stability times for voltage and speed within specification. At 14.5 seconds after the Division 1 engine start, the generator voltage vas lost and the governor shifted to mechanical control, accelerating to the rated mechanical setpoint of 477 RPM. Voltage decay was normal for loss of excitation; however, no field reflash was exhibited. All indications on the Engine Control Panel vere normal and no alarms were received either remotely in the Control Room or locally in the Diesel Generator Room. All engine operating parameters were normal. The engine was stopped at 1415 for troubleshooting without further incident.

The troubleshooting investigation identified no deficiencies with the field breaker K1 closing coil or the field flash relay K2 coil. The generator voltage sensing relay K3 contacts closed as expected; however, at no time was the field reflashed after the loss of voltage. Because the 200 RPM relay R11 vas sealed-in, a reflash of the field should have occurred by the time generator voltage decayed to zero, provided that the field breaker K1 was closed. Troubleshooting, however, indicated that the field breaker K1 had spuriously opened.

Normally, reset of field breaker K1 is caused by operation of shutdown relay RS. Had the shutdown relay RS operated, the engine vould have been tripped.

The continued operation of the engine confirmed the field breaker K1 trip to be spurious. Maintenance replaced the defective field breaker K1 (Basler part number 9-1183-01-001) with a new component. The new K1 contactor was procured, inspected, cleaned and tested prior to installation. Two successful maintenance runs vere performed to verify proper latching on field breaker K1 prior to performance of the surveillance test for operability.

The Division 1 Diesel Generator was declared operable on December 23, 1989 at 2125.

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L Attcchment PY-CEI/NRR-1120L Page 2 of 2 Failure analysis of the original contactor on the defective field breaker l K1 revealed that the lubricant on the latch mechanism pivot point had degraded due to aging. Spring tension was unable to overcome the frictional resistance to properly extend the latching mechanism. It was concluded that the latch mechanism did not fully latch behind the trip mechanism allowing the contactor to unlatch due to normal tension and vibration. The valid test failure was considered to be an equipment malfunction attributed to insufficient maintenance and lubrication of the latching mechanism. The K1 contactor had been previously inspected during the first refueling outage (March, 1969) havever, the latch mechanism was not specified as an item requiring inspection or service.

The Division 1 Diesel Generator failed to maintain specified generator voltage and was declared inoperable on December 22, 1989 at 1400. The Division 1 Diesel Generator was subsequently declared operable on December 23, 1989 at 2125. The total out-of-service time for the Division 1 Diesel Generator was 1 day, 7 hours8.101852e-5 days <br />0.00194 hours <br />1.157407e-5 weeks <br />2.6635e-6 months <br />, and 25 minutes.

Satisfactory operation of the trip latch mechanism on the Division 2 Diesel Generator field breaker K1 was verified on December 23, 1989. Additional corrective actions included the initiation of a work order to service the Division 2 Diesel Generator field breaker K1. This work vill be performed in the next quarterly outage currently scheduled for February 12-16, 1990.

Periodic Maintenance Instruction (PMI-088, Rev. 0), " Diesel Panel Maintenance" vill incorporate specific inspection and service requirements for both Division 1 and 2 field breakers Kl. The procedural change vill be completed by March 15, 1990.

The Division 1 Dicsel Generator Surveillance Test interval vill remain at once every 31 days in accordance with Perry Technical Specification Table 4.8.1.1.2-1.

NJC/ CODED /3085 I

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