ML17309A154

LER 81-007/03L-0:on 810418,loss of 34.5-kV Supply to Transformer 12 Occurred,Creating Loss of Offsite Power. Caused by Fault in B Phase Vacuum Breaker Switch Which Supplies Spare Transformer 12B

ML17309A154
Person / Time
Site:	Ginna
Issue date:	05/11/1981
From:	Edgar C ROCHESTER GAS & ELECTRIC CORP.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML17258B043	List: ML17258B042 ML17258B044 ML17309A154
References
LER-81-007-03L, LER-81-7-3L, NUDOCS 8105180308
Download: ML17309A154 (4)

Text

LER 81-007/3L-0 LICENSEE EVENT REPORT CAR 1300 1)3)4)7)8)10)Control Block: License Type: I 4', 1'1,',1', 1', Docket Number: I 0 I 5 0 0 0 2 Event Date'IOI 11 I I 11 Event Description and Proba 2)Licensee Code'.'N'Y',R',E',G 0 I 0'0 I-I 0 I 0', 5 Cat: I I/6)Report Source 9 Report Date'0'5'1111811 I ble Consequences:

~I L I~I I e IDurin steady state operation a loss of the 34.5KV supply tof INo.12 transformser occured creating a loss of offsite power/,to anna tation.is created a loss of power to 1 I usses and 1 and sa eguar busses an 11.Emergency D/G's 1A and 1B started on undervoltage signalI I and suppl ied power to the OV safeguard busses.The temporary I Iinterruption to the ower supply for the 1B instrument bus 11)14)17)18)21)23)25)27)System Code'E A I 1 2)Cause Code: ', E', 1 3)Cause Subcode: I A I Comp.Code:/,~C/K/T/BIRIKI 15)Subcode;/X/16)Valve Code:jZ/~'-7'/'ction Taken: IX'19)Future Action: ',Z', 20 Effect on Plant: ',B', Shutdown Method: I Z I 22)Houl s'0 I 0 1 0 I5 I Prime Component Supplier: IL I 26)Manufacturer:

',J',1'I~2,0', Cause Description and Corrective Actions: ',The cause was identified to a fault in the"B" Phase vacuumf',breaker switch which supplies the 12B spare transformer.,The 12 transformer was isolated from the 3.5KV bus and power>',was restored to the No.12 transformer.

The safe uard busses', ,were transferred bac to t eir normal supply and the emerpency',',Diesel Generators secured.28)30)31)32)33)35)36)37)39)40)41)42)43)44)45)Facility Status: ',E', Other Status: 1N/A1 Method of Discovery:

IAI Discovery Description~IOperator Ob Activity Released: I Z I 3 Content Amount of'ctivity:,I/A I Location of Release:/N/Al Personnel Exposures Number: 10 0 I 0 I

Description:

', N/A I Personnel Injuries Number: ',0',0',0',

Description:

IN/AI Loss of or Damage to Facility: I Z I

Description:

I N/A I Publicity Issued: I N I

Description:

/N/Al IOI9I5 I servationi of Release: IZI 38)Exposures Type: ', Z', NRC USE ONLY Name of Preparer: Clair Edgar Phone: 315-524-4446 x248

ATTACHMENT TO LER FORM 10)Event Description and Probable Consequences contd: 'caused numerous alarms and an approximate 105 runback to', 5 nuclear power.Conditions were stablized by operationsI

<personnel and plant o eration continued.

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