ML20206G977
| ML20206G977 | |
| Person / Time | |
|---|---|
| Site: | Sequoyah  |
| Issue date: | 11/21/1988 |
| From: | Richardson S NRC OFFICE OF SPECIAL PROJECTS |
| To: | |
| References | |
| PNO-OSP-88-018A, PNO-OSP-88-18A, NUDOCS 8811230050 | |
| Download: ML20206G977 (1) | |
Text
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November 21, 1908 PRILIMINARY NOTIFICATION OF EVENT OR UNUSUAL OCCURRENCE PNO-0SP-88-018A This preliminary notifiution constitutes EARLY notice of events of POSSIBLE safety or public interest significance.
The information is as initially ree<ived without verifi-cation or evaluation, and is basically all that is known by OSP staff on this date.
j FACILITY: Tennessee Valley Authority Licensee Emergency Classification:
Sequoyah Units 1 and 2 Notification of Unusual Event Docket Nos. 50-327 and 50-328 Alert Soddy Daisy, Tennessee Site Area Emergency General Emergency
_X _Not Applicable i
SUBJECT:
SEQUOYAH UNIT 1 REACTOR TRIP UPDATE On November 18, at 10:04 a. n.
(EST), Unit 1 tripped from 72*; reactor power upon receipt of a turbine trip signal.
The root cause was determined to be an electrical ground in the main generator.
The grounded condition resulted in an overvoltage on the m:in generator neutral transferrer causing the generator output breakers to open initiating a turbine trip.
The licensee completed a controlled cooldown to mode 5.
The licensee has initiated outage work including repair of the main generator, repair of the RCP #3 seal l
package, repair of all steam dumps, evaluate RC3 pressure vessel o-ring leakage, and repair several safety valves.
Current schedule for restart is approximately December 17, 1988.
[
This PN is current as of 11:00 a.m. (EST) on November 21, 1988.
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t CONTA;T: S. Richardson 49-23286 I
DISTRIBUTION 5520:
Mail:
LTaTrnan Zech - INRC1718/ZECHPN ICIS Comissioner Roberts - INRC1718/Leadop DCS l
Comissioner Carr - INRC1718/CARRPN OIA-kNBB-8607 Comissioner Rogers - INRC1718/Leadop O!- 3E4-DLewis Comissioner Curtiss - 1NRC1718/Leadop OSP SECY - INRC1718/Leadop CA - INPC1718/0CAPN PA - INRCO?/0PADN ARM - NPCRM/Browr, Reginnal Offices AEOD - NRCAF0D/AE0DPN Region I - RI/Leadop Pqs Oper. Office - NRCAE00/AEODPN Reoion !! - RII/Leadop NRR - INRC1112/NRRPN Sequoyah Resident Inspector OE - INRC0708/0EPN Licensee:
TVA LMSS - INRC0506/hM*SPN Region III - PIII/Leadop OGC - INRC1516/0GCPN Degion IV - RIV/Leadop SP - INRC0304/SLIPN 9ecien V - RV/Leadep EPO - 1NRC1718/EDOPN DEDRO - INRC1'18/E00PM GPA - INDC1718/0CAPN oES - NRCRES/RESPN 4
s g 12 p o esing I
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