ML19256C735
| ML19256C735 | |
| Person / Time | |
|---|---|
| Site: | Arkansas Nuclear  |
| Issue date: | 08/14/1979 |
| From: | Mckee P, Nolan F NRC OFFICE OF INSPECTION & ENFORCEMENT (IE) |
| To: | |
| References | |
| PNO-79-333, NUDOCS 7910110723 | |
| Download: ML19256C735 (1) | |
Text
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e-PRELIMINARY NOTIFICATION
. _ _ _ ___ _m August 14, 1979 f
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PRELIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE--PNO-79-333 This oreliminary notification constitutes EARLY notice of events of POSSIBLE safety or public interest significance.
The information presented is as initially received without verification or evaluation and is basically all that is known by IE staff on this date.
FACILITY:
Arkansas Power and Light Company Arkansas Nuclear One (AN0), Unit 1 Russellville, Arkansas Docket No. 50-313
SUBJECT:
TRIP 0F UNIT 1 FROM 90% POWER At 5:49 p.m. on August 13, 19.79 ANO-Unit 1 reactor tripped from approximately 90% power. A failure in the turbine control circuit caused the turbine to trip.
Following the turbine trip the turbine lockout relay failed to operate preventing a fast transfer of electrical loads from the auxiliary transformer to the start-up transformer and coincident reactor trip.
Eight seconds after the turbine trip, the reactor tripped on high pressure, and a generator trip followed.
Repairs have been made to the turbine control circuit and turbine lockout relay and the reactor was returned to criticality at approximately 3:00 p.m. on August 14, 1979.
The turbine turning gear failed to autostart as the turbine coasted down and the turbine rotor sat for approximately one hour before the turning gear motor could be started. While attempting tc roll the turbine, a turbine trip occurred due to high bearing vibration.
The reactor is currently at 10% power while warming up the turbine.
A press release is not planned.
The Region IV duty officer was first notified of this event by the licensee at 7:00 p.m. on August 13, 1979.
Contact:
PMcKee, IE x28019 FNolan, IE x28019 Distribution:
Transmitted H St Chairman Hendrie Commissioner Bradford S. J. Chil k, SECY Cc-,issioner Kennedy Commissioner Ahearne C. C. Kammerer, CA Cc issioner Gilinsky ACRS (For Distribution)
Transmitted:
MNBB P. Bldg kN V. Stello$ IE L. V. Gossick, EDO H. R. Denton, NRR Region 1 H. L. Ornstein, ED0 R. C. DeYoung, NRR J. J. Fouchard, PA R. J. Mattson, NRR N. M. Haller, MPA D. Vassallo, NRR (MAIL)
R. G. Ryan, OSP D. Eisenhut, NRR J. J. Cummings, OIA H. K. Shapar, ELD SS Bldg R. Minogue, SD W. J. Dircks, NMSS 1I/7 061
- 5. Levine, RES t4
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PRELIMINARY NOTIFICATION rg 91011
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