ML19326D983

From kanterella
Jump to navigation Jump to search
RO 80-20:on 800715,w/Unit 2 at 100% Power & Unit 1 at Cold Shutdown,Main Generator Separated from Grid & One Offsite Source Was Lost,Tripping Reactor & Coolant Pumps.Caused by Severe Electrical Storm.Transformer Restored
ML19326D983
Person / Time
Site: Prairie Island  Xcel Energy icon.png
Issue date: 07/16/1980
From: Tierney F
NORTHERN STATES POWER CO.
To:
References
NUDOCS 8007250340
Download: ML19326D983 (1)


Text

__

TO ' O ? b-So to M f3 9 NORTHERN STATES P'O W E R COMgANY PIL\llllE ISLAND NUCLEAll GENEllATING PLANT 1111 # 2 Welch, .\lN 35089 July 16, 1980 Mr. James G. Keppler, Director 4

Regica III Office of Inspection and Enf orcement U S Nuclear Regulatory Corr.ission 799 Roosevelt Road Glen Ellyn, IL 60137 ATIN: W. S. LITTLE Reportable Occurrence No. 80-20 On 7/15/80 with Unit 2 at 100% power and Unit 1 at cold shutdown, a severe electrical storm caused operation of several breakers in the substation. At about 2030 the main generator was separated from the grid and one of fsite source was lost and the reactor and reactor coolant pumps tripped. Natural circulation was established for core cooling.

At about 2138, No. 10 Transformer was locked out and with only one offsite source remaining (a degraded one) , th diesel generators started and closed in on the safeguards buses. Ne safety injection was actuated.

At about 2240 the Cr11 source was restored and at 2319 No. 10 Transforcer was restored putting the plant back within Tech Specs. At 0137 the next day, the substatien was completely nornal and Unit 2 is now operating at 100% power.

ely ,

& M A y F. P. Tierney , J r.

Plant Manager Prair4.e Island Nuclear Plant FFT/maj cc: L. O. Mayer ~

eDirector, MIPC (2) m

- " N = tr(bution Services Branch, DDC, ADC C. D. Feierabend

. Gdh

. /g 8007250.3/tf