ML20058K745

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Ler:On 750119,discovered Refueling Bridge Limit Switch Did Not Actuate Preventive Rod Block W/Bridge Over Core/Reactor Mode Switch in Startup
ML20058K745
Person / Time
Site: Monticello 
Issue date: 01/29/1975
From: Anthony D, Mayer L
NORTHERN STATES POWER CO.
To: Anthony Giambusso
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
LER-LER-750129, NUDOCS 9102130564
Download: ML20058K745 (2)


Text

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NSID NORTHERN STATES POWER COMPANY M 8 N N E A PO Li m. M 6 N N E SOTA 55401 January J3, 1975 Q:-

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Mr. A. Giambusso, Director Division of Reactor Licensing U S Nucicar Regulatory Commission Wasnington, DC 20555 Licensee Event Report to the 1;RC Failure of Refueling interlock Limit Switch

Dear Mr. Giambusso:

Die 1icensee Event Report for this occurrence is reproduced on :he back of this letter.

Yours very truly, i)')[1 /)4

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L 0 Mayer, PE Manager of ::uclear Support Services LOM/MHV/yb cc:

J G Reppler G Charnon Minnesota Pollution Control Agency Attn:

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$ ! Durine Su veillance test, refueline briage lirait 80 h ! block with aridee over core and reacCor mode switch in startup. I;c redundant l

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switch failed to actuate due to loose actuating am.

$l Limit 80 GE limit switch l

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