ML19290C326

LER 79-124/03L-0:on 791208,component Cooling Water Pump 1 Would Not Start.Caused by Failure of Breaker AC113 on Essential Switchgear Bus C1 to Close.Breaker Replaced & Pump Returned to Svc

ML19290C326
Person / Time
Site:	Davis Besse
Issue date:	01/05/1980
From:	Rudolph J TOLEDO EDISON CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
Shared Package
ML19290C322	List: ML19290C321 ML19290C326
References
LER-79-124-03L, LER-79-124-3L, NUDOCS 8001100532
Download: ML19290C326 (2)

Text

U.S. NUCLEAR REGULATORY COMMISSION NRC FORM 36G (7-77)

LICENSEE EVENT REPORT CONT ROL e' OCK: l l l l l (PLE ASE PRINT OR TYPE alt REQUIRED INFORMATION) 1 6 0 1 0 l 11 D l B l S l 114l@l150 0 l- l 0 l0 N l P l F l- l 0 l 3 25l@l 264 1LICEN5E l1 l1TYPEl1 JJl@l$ 1 L lA I $8lg i 8 3 LICE *.SE E CODE LICE Nh NUNR CON'T o i %g"c',

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bd 63 EVENT DATE 74 75 REPORT D ATE 83 I 8 60 bl DOCKET NUYBER EVENT DESCRIPTION AND PROBABLE CONSEQUENCES h j o 2 On December 6,1979 operations personnel atter pted to start Component Cooling Water o  : ) (CCW) Pump #1 for routine pump switching. The pump would not start from the Control l o .i jRoom. The pump was declared inoperable at 2300 hours0.0266 days <br />0.639 hours <br />0.0038 weeks <br />8.7515e-4 months <br /> on December 8, 1979. This occury lrence is being reported to document a component failure. There was no danger to the j o 3 o 6 l health and saf ety of the public or station personnel. CCW Pumps #2 and #3 were (NP-33-79-144) l o(7 l available for service and the unit was in Mode 5.

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42 43 44 41 CAUSE DESCRIPTION AND CORRECTIVE ACTIONS i o lThe cause of the occurrence was the f ailure of breaker AC113 on essential switchgear

]i ji j bus "C1" to close. The breaker was removed from the cubicle and a spare was installed) j 1il7] jand the #1 CCW Pump was returned to service on December 15, 1979. The cause of the lij3j ] breaker failure is presently being investigated.

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[1 14 1 I 80 7 8 9 OTHER STATUS DSO RY DISCOVERY DESCRIPTION STA S . POWER NA l i 5 G l@ 0l 0l0l@lNA l lAl@l ACTIVITY CONTENT AYOUNT OF ACTivlTY LOCATION OF RELEASE RELE ASED OF RELE ASE l NA l' 168 9I W @ bh]

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45 80 PERSONNEL E XPOSURES NUY9ER TYPE DESCRIPTION l

li1711010101@l Z @l NA PERSONNEL INJURIES NUY9ER DESCRIP TION lt ls l l 0l 0 O l@l NA 80 1 8 9 11 12 LOSS OF OR DAVAGE TO FACILITY l: l o I LZj@l TYPE D E SC RIP TIO N NA 8001100 1 80 l

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@ N 4 %,En. M DVR 79-189 NdME OF PREPAHER ames P. N o @ pgggg;

TOLEDO EDISON COMPANY DAVIS-BESSE NUCLEAR POWER STATION UNIT ONE SUPPLEMENTAL INFORMATION FOR LER NP-33-79-144 DATE OF E.ENT: December 8, 1979 FACILITY: Davis-Besse Unit 1 IDENTIFICATION OF OCCURRENCE: The #1 Component Cooling Water Pump was declared inoperable Conditions Prior to occurrence: The unit was in Mode 5, with Power (MWT) = 0, and Load (Gross MWE) = 0.

Description of Occurrence: On December 6, 1979, operations personnel attempted to start Component Cooling Water (CCW) Pump fl for routine pump switching. When the pump did not start from the Control Room, maintenance and instrument and control pet sonnel were called in for investigation.

The investigation found that the breaker was the cause of the problem, and the pump was declared inoperable at 2300 hours0.0266 days <br />0.639 hours <br />0.0038 weeks <br />8.7515e-4 months <br /> on December 8,1979.

This accurrence is being reported to dccument a component failure. Technical Speci-fication 3.7.3.1 requires two independent CCW loops to be operable in Modes 1 through

4. Since the plant was in Mode 5, and CCW Pumps #2 and #3 were operable, no action statement was entered.

Designation of Apparent Cause of Occurrence: The apparent cause of the occurrence was the failure of breaker AC113 on essential switchgear bus "Cl" to close. The cause of the failure 1, still being investigated. ,

Analysis of Occurrence: There was no danger to the health and safety of the public or to station personnel. The subject pump is redundant in the CCW System. CCU Pumps

1. 2 and #3 were availabic for service at this time.

Corrective Action: The breaker was removed from the cubicle and.a spare was installed on December 15, 1979 under Maintenance Work Order (MWO) 79-3723 and the #1 CCW Pump was returned to service on December 15, 1979. The cause of the breaker failure is presently being investigated under the same MWO.

Failure Data: There have been no previous similar reportable occurrences.

LER #79-124 1727 113