ML19256F268

Forwards Info Re Loss of Offsite Power,In Response to 791002 Ltr to AR Barton

ML19256F268
Person / Time
Site:	Farley
Issue date:	12/07/1979
From:	Clayton F ALABAMA POWER CO.
To:	Schwencer A Office of Nuclear Reactor Regulation
References
NUDOCS 7912180397
Download: ML19256F268 (3)

Text

• 'r ? Alabama Power Company 600 North 18th Street Post Office Box 2641 Birmingham. Alabama 35291 Telephone 205 323-5341 L

hbo?dc','R;@nt Alabama Power the Southern electrC bystem Decarber 7,1979 Eccket Ib. 50-348 Mr. A. Schwncer, Chief Operating Reactors Branch No. 1 Division of Operating Pcactors thiclear Pegulatory Cannission Washington, D. C. 20555 Re: Letter from A. Schencer to A. R. Barton dated October 2, 1979. IOSP

Dear Mr. Schwencer:

In response to the above referenced letter, Alabmra Powr Orpany subnits the attached.

Yours very truly, 4

F. L. Clayto$ Jr.

~4 FICjr/HPF/mrb cc: Mr. R. A. Thomas Mr. G. F. Trowbridge Office of I&E Division of Peactor Operations InoW on Washington, D. C.

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b ATTAClon?

A. For losses of offsite powr where less than all offsite power wns lost:

1. How nuny circuits to the offsite network are normally available and how many were lost during the event?

RESPONSE

'Iko circuits are normally available to the off-site network.

One circuit was lost during the event.

2. hhat was the cause of the event?

RESIONSE:

Water entered a faulty connector on the 1B startup transformar sudden pressure relay, causing a ampleted circuit which re-sulted in a spurious overpressure trip of the 1B startup trans-forner feeder breaker to 4.16 KV Bus 1G.

3. hhy did the other lines not fail when sorre did fail?

RESPONSE

The other line did not fail because the fault was not associated with IA startup transformer or any transformar supply breakers.

4. Was any voltage increase or decrease experiencM just prior to or during the cutage? If so, please give details, voltages reached, affects, etc.

RESPCNSE:

No voltage increase or decrease was recorded prior to or during the outage.

5. Was any frequency decay experienced just prior to or during the outage?

If so, please give details, lowest frequency reached, decay rate, affects on equipnt operation, etc.

FESPONSE:

No frequency decay was recorded prior to or during the outage.

6. How long was power unavailable from the circuit?

RESPONSE

Power was unavailable from 1B startup transformer for 5 hours5.787037e-5 days <br />0.00139 hours <br />8.267196e-6 weeks <br />1.9025e-6 months <br /> and 31 minutes.

7. Date of Event.

RESPCNSE:

8/12/78 1608 183

. - e.

A ATTAODENT B. Ebr losses of all offsite powr:

1. How long was the power off? How long for partial recovery?

Please give details.

RESPONSE

Power was off for 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br /> and 59 minutes. Partial recovery occurred 54 minutes after IOSP when #1230 KV Bus was energized by closure of gas circuit breakers 924 and 820, energizing startup transformer lA.

2. It 'urbine trip occurred, how soon after did loss of offsite power occur?

RESPONSE

Turbine trip did not occur since gas circuit breakers 914 and 810 (Generator output breakers) were open.

3. If pomr was recovered prcmptly (10 minutes or less), was it due to automatic or manual actions?

RESEONSE:

Power was not recovered prceptly (10 minutes or less) .

4. Was any voltage increase o; decrease experienced just prior to or during the outage? If so, please give details, voltages reached, affects, etc.

RESPWSE:

No voltage increase or decrease was recorded prior to or during the outage.

5. Was any frequency decay experienced just prior to or during the outage?

If so, please give details, lowest frequency reached, decay rate, affects on equipment operation, etc.

RESPONSE

No frequency decay was recorded prior to or during the outage.

6. Date of Event.

RESPCNSE:

9/16/77.

C. Were there any other loss of offsite power events other than we have listed?

If so, please give details of each event.

RESPOt;SE:

No other IDSP events have been experienced at R2.

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