05000306/LER-1979-026-01, /01T-0:on 790919,during Power Reduction Below 90% Power,Axial Flux Difference Left Target Band While Power Was Still Above 90% Power.Caused by Operator Error.Power Reduced to Below 90% & Event Discussed W/Personnel

/01T-0:on 790919,during Power Reduction Below 90% Power,Axial Flux Difference Left Target Band While Power Was Still Above 90% Power.Caused by Operator Error.Power Reduced to Below 90% & Event Discussed W/Personnel

ML19209B234
Person / Time
Site:	Prairie Island
Issue date:	10/03/1979
From:	Hunstad A NORTHERN STATES POWER CO.
To:	NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
Shared Package
ML19209B232	List: 05000306/LER-1979-026, Forwards LER 79-026/01T-0 05000306/LER-1979-026-01, /01T-0:on 790919,during Power Reduction Below 90% Power,Axial Flux Difference Left Target Band While Power Was Still Above 90% Power.Caused by Operator Error.Power Reduced to Below 90% & Event Discussed W/Personnel
References
LER-79-026-01T, LER-79-26-1T, NUDOCS 7910090362
Download: ML19209B234 (1)

LER-1979-026, /01T-0:on 790919,during Power Reduction Below 90% Power,Axial Flux Difference Left Target Band While Power Was Still Above 90% Power.Caused by Operator Error.Power Reduced to Below 90% & Event Discussed W/Personnel

Event date:
Report date:
3061979026R01 - NRC Website

text

NRC FORM 366 U. L NUCLEAR REGULATORY COMMISSION (7 77)

LICENSEE EVENT REPORT CONTROL BLCCK: l l

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60 61 DOCKET NUMBER 68 69 EV5NT DATE 74 75 REPORT DATE 80 EVENT DESCRIPTION AND PROB ABLE CONSEQUENCES h 10 I 21 l During a power reduction to below 90% for axial of fset calibration, axial flux l

I O l a l l dif ference was allowed to leave the target band while reactor power was still above l o

4 190%.

Power was reduced to below 90% in half an hour.

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