ML20084T548

Telecopy Ro:On 721005,two of Four Low Reactor Pressure Switches Had Tripped Setting Greater than Tech Spec Limit. Cause Not Stated.As Left Setting Changed to Ctr of Tech Specs Pressure Range,Allowing Greater Margin for Drift

ML20084T548
Person / Time
Site:	Dresden
Issue date:	10/05/1972
From:	Worden W COMMONWEALTH EDISON CO.
To:	Grier B NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
Shared Package
ML20084T542	List: ML20084T539 ML20084T545 ML20084T548
References
NUDOCS 8306230258
Download: ML20084T548 (1)

Text

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.c. a ^ '9-444 A EST OCT 6 72 DEA 544 DE kgg &

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PMS BOYCE GREAR DIR DIV 0F COMPLIANCE, DLR DONT FONE $3 P h h

REGION 3 US ATOMIC ENERGY COMM 799 ROOSEVELT RD $ gn ,

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GLEN ELLYN/ILL J 3J kg

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SUBJECT DPR2$ DRESDEN NUCLEAR POWER STATION UNIT 3.

${ _ -e THIS VILL CONFIRM A CONVERSATION WITH MR H. DANCE OF YOUR 0FFICE AT 1400 HOURS THIS DATE CONCERNING ECCS 350 PSI h kh f LOW REACTOR PRES 3URE SWITCHES BEING OUT OF CALIBRATION SHOWE 3{ 8g e3o d --

' THAT TWO OF THE FOUR SVITCHES HAD TRIPPED SETTING GREATER TH o f _

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THE LIMIT IN TABLE 3.2 2. OF TECHNICAL SPECIFICATIONS. M$z O 1 'O Q LS O 3 ef38

) TABLE 3n2 2. STATE THE TRIP SETTING SHOULD BE GREATER THAN "3

, 330 PSIG AND LESS THAN 350 PSIC PRESSURE SWITCH 3-263-5 2A2 y f j ; q'Yg', f' I sr. ins <=

TRIP SETTING WAS FOUND TO BE 371 PSIC. PRESSURE SVITCH OCT 101972 iE 65 4 ~

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C-33-263-52B2 TRIP SETTING WAS TOUND TO BE 354 PSIC.

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PRIOR TO THIS CALIBRATION THE *AS LEFT" SETTING ON THESE h

SL' ITCHES VAS 355 PLUS OR MINUS 5 PSIC. OUR LIMIT FOR THESE (

SWITCHE3 HAS NOW'BEEN CHANGED TO 325 PLUS OR MINUS 10 PSIG. '_(

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• THIS SETTING IS IN THE CENTER OF TECHNICAL SPECIFICATIONS PRESSURE RANGE AND ALLOWS GREATER MARGIN FOR INSTRUMENT DRIFT

{ 'b' WALTER P. WORDEN, SUPT.

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DRESDEN NUCLEAR POWER STATION .[h 'g DPR25 3 1400 ECCS 350 PSI 10-4-72 1600 3.2.2. 3.2.2 330 350 N g 90 21M j 3-263-52A2 371 33-263-32B2 356 355 5 325 10 gG 1 -

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