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 CAR 1300 LICENSEE EVENT REPORT

1) Control Block: 2) Licensee Code'. 'N'Y',R',E',G

3) 0 I 0'0 - I I 0I0 ',

4) License Type: I 4', 1'1,',1 1', 5 Cat: ',

I I / 6) Report Source ~

~

I I L II

7) Docket Number: I 0 5 0 0 0 2 I

8) Event Date'IOI 11 I I 11 9 Report Date'0'5'1111811 I

10) Event Description and Proba ble Consequences:

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) System Code ' E A I 1 2) Cause Code: ', E ', 1 3) Cause Subcode: I A I

14) Comp. Code: /,~C/K/T/BIRIKI 15) Subcode; /X/ 16) Valve Code:jZ

17) / '-'

18) Taken: IX'19) Future Action: ',Z', 20 Effect on Plant:

'7'/'ction

',B',

21) Shutdown Method: I Z I 22) Houl s' 0 I 0 0 I5 I 1 23)

25) Prime Component Supplier: IL I 26) Manufacturer: ',J',1'I~2,0',

27) 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) Facility Status: ',E', IOI9I5 I

30) Other Status: 1N/A1

31) Method of Discovery: IAI

32) Discovery Description~IOperator Ob servationi

33) Activity Released: Z Content of Release: IZI

35) Amount of'ctivity:,I/A3 I I I

36) Location of Release: /N/Al

37) Personnel Exposures Number: 10 0 I 0 I 38) Exposures Type: ', Z ',

39)

Description:

N/A ',

I

40) Personnel Injuries Number: ',0',0',0',

41)

Description:

IN/AI

42) Loss of or Damage to Facility: Z I I

43)

Description:

N/A I I

44) Publicity Issued: N I I

45)

Description:

/N/Al 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.

l