ML20084N853

Telecopy Ro:On 750826,isolation Condenser Pressure Switches PS3-263-53A,53B & 53C Setpoints Above Tech Spec Limit. Probably Caused by Setpoint Drift Due to Inactivity During Refuel Outage

ML20084N853
Person / Time
Site:	Dresden
Issue date:	08/28/1975
From:	Stephenson B COMMONWEALTH EDISON CO.
To:	James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
Shared Package
ML20084N845	List: ML20084N841 ML20084N853 ML20084N859 ML20084N861
References
NUDOCS 8306090094
Download: ML20084N853 (1)

Text

{{#Wiki_filter:- . oE O [ '.5 \\ Oe O mestem union w 7. r 3 _ y p 9, m vee 060c0857)ca-007584E240>eD as/as/75 0857 fyfg O, O ICS IPM3NGZ CSP 27 "ji;$. Ik O sis 9424449 TDaN MORRIS IL 206 08-28 0830A CDT O PMS JAMES G KEPPLER, REGIONAL DIRECTOR DIRECTORATE OF REGUL ATORY $[ O OPERATIONS REGION III, wux E US NUCLEAR REGULATORY COMMISSION 799 ROOSEVELT RD O O GLEN ELLYN IL 60137 SU3 JE CT : DPR-25, DRESDEN NUCLEAR POWER ST ATION, UNIT 3. THIS WILL b Oh O CONFIRM A CONVERSATION WITH MR R KNOP 0F YOUR OFFICE AT 1710 HOURS E 3-26-75 CO NCERNIN3 INSTRUMENT DRIFT OF 1. ISOLATION CONDENSOR SUST AINED HIGH REACTOR PRESSURE SWITCHES O b PS3-263-53 A,B&C TO ABOVE THE TECH. SPEC. LIMIT OF LESS THAN OR EQUAL O TO 1070 PSIG. PS3-263-53 A WAS FO UND AT 1090 PSI; 53B AT 1087 PSI; 53C O AT ll22 PSI. SWITCHES ARE MELETRON TYPE AND DRIFT IS BELIEVED CAUSED E Oh O sY INACTIVITY CAUSED BY CURRENT REFUEL OUIAGE. ~

2. ADDITIONALLY, REACTOR PRESSURE ECCS INITI ATION.p4 TTf.y(MITS OF PS3-263-52A-1 AND 52N-2 WERE ALSO FOUND AB0VE TECH. SPEC' LI

-= bokSIALkSI THAN..QR EQUAL eT0kP. LESS THAN OR EQUAL TO 350PSIG. THE { ^ MELETRON SWITCHES WERE FOUND AT 365 PSI (A-1) AND 366 PSI (A-2). TH ~, i DRIFTS ALSO ARE BELIEVED TO BE CAUSED BY INACTIVITY. ~ MAIN STEAM LINE DRAIN ISOL AT IO N V ALVE M03-220- 1, DURING =_ 3. MAINTENANCE, W AS FOUND WITH A FAILED OVERLOAD RELAY WHICH CAUSED j MALOPERATION OF THE VALVE DURING TESTING. PRIMARY CONT AINMENT -{ INTEGRITY MAY H AVE BEEN AFFECTED IN THE SINGLE FAILURE MODE WOU O-O HAVE AN ISOLATION DURING OPERATION OCCURRED. ADDITIONAL INFO WILL FOLLOW IN A TEN DAY REPORT. O 3 B STEeHENSON SuedR' hTENDENT DRESDEN NUCLEAR POWER STATION

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{~ h k. 7, g' D O e UNITED STATES NUCLEAR REGULATORY COMMISSION OFFICE OF INSPECTION AND ENFORCEMENT REGION til 799 ROOSF.VELT RO AD CLEN ELLYN, ILLINOIS 60137 A.. IE Inspection Report No. Transmittal Date Distribution: Distribution: IE Chief, FS&EB IE Chief, FS&EB IE:HQ (5) IE: LIQ (4) DR Central Files L:D/D for Fuels & Materials Regulatory Standards (3) DR Central Files Licensing (13) IE Files ~ IE Files IE Chief,' M&FPB L:D/D for Reactor Froject B. IE Inquiry Report No. Transmittal Date Distribution: Distribution: IE Chief, FS&EB IE Chief, FS&EB IE:HQ (5) IE:HQ DR Central Files DR Central Files Regulatory Standards (3) IE Files Licensing (13) IE Files C. Incident Notification From: Commonwealth Edison Co. 50-249 ~ (Licensee & Docket No. (or License No.) Transmittal Date

September 3. 1975 Dresden Station #3 Distribution:

Distribution: TE Chief. FS&EB IE Chief, FS&EB IE:HQ-(4) IE:HQ (4) Licensing (4) L:D/D for Fuels & Materials-DR Central Files DR Central Files l IE Files IE Files l ML $*tur,0,, 0

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