ML20086K471

Telecopy AO 74-35:on 740702,condenser Low Vacuum Scram Presssure Swith Setpoint Found Less Conservative than Limiting Safety Sys Setting.Caused by Instrument Drift Switch Recalibr & Checked for Setpoint Repeatability

ML20086K471
Person / Time
Site:	Peach Bottom
Issue date:	07/03/1974
From:	Ullrich W PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20086K464	List: ML20086K462 ML20086K471
References
AO-74-35, NUDOCS 8401270132
Download: ML20086K471 (2)

Text

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pr, ,n c r. P. O'Reilly, Direc t or ,

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Directorate of Ecp ute:,, Op^rra m.c _;,

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A.E.C. P.cglon 1 Regulo.ory Operations Offico on uly .

peterence: Licenco Hunber Er ' 4, t.-endment Un-M 1 ,

Tcchnical specifr. .1 n Table .?.1.1 Repcrt No.: 50-E77-7b-33 F et. ort Drit e : July 3. 1974 O[currer.ccPa'e: Jul; 2 l')74 .

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Peach Latten Atcric Pever m,Latic, F.T. 1, Delto, Pennrylu n,.* l-@. .

v.*ent '" cstion of Oc currence :

Co. r.r e r lo s vr3 c uu r- ceran pret cu-e c,titch retraint f.rJnd to be leen cencervative than the linitint cafety cyctcn cettarr.

Conlitic: prier to Occurrm

• Tnt rr_sc.or n c at 9 m, power.

a cf Occurrrnce:

Dcr-[rhtif i r'ngouti:.'- n in t ru ..nt curvc ill .n c e tent of P.~-E-3 11A, r u.n conden er trip ir.put into the reactur proteciicn t77:tre, the tx.. act .

% vitch voeuub sn found to trip at 19.2 in. Hg. Thic in 3 3 1% Eg la,a cor ,{,

thrin the Tccimical Specificaticn cetpaint of greater than or eqra to 6 La - :, *

+l Der-ignntion cf App,rr:nt Cause of Or.:rrence:

ht; int f ailure is attributed to instrument drif t.

Annivnic of Cccurrenc-:

Ph-2-5-ll A ia one el ar.nel in n one-out-of- two twice le-ic > arrt.nge- ent. The.

cetraint fsilure vauld not hs*.e p' nented the device fro :.nitinti*g n trip ci, nl. ne prc'ection provido:1 by the other three channoin of condtnEcr racer, sculd have beer. Untiart.c;  : frc a ctudpoint of P1 3Lt L3fCt7*

h erefore. thic occurrence hn- nininni cafety icplicationc.

Corrective Actic -

Tr.e t,ub

• e 't r, it ch un c i~~ edio t' rcc,11brated, chcched fcr cotFDin' repe:itibili + . ind ret err.03 ' c re: . ice, O u other three twitchen c nitoric?

condeneervi[cuumr.ndprovidingthe FWSinputewereit.gdiatelgtertcdnnd &-

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Thic in 't$ie fo'artF cetroin*, f ailm of thin type of dcvice in thin cervice.

Other Eccyrrencco cre o C hllovc:

PE-2-5-11A on &drJ3ry S.197f P.%2-5-11D en Jar.usry 5, 1 9' PS-2-5-11A on 19118 IW4 After the t.a cetreint failures of TS11A, the device v,a repiceed in kir.d.

' This failure in the first cetpoint failure cf the replacem at d anc e.

m Very truly 70'.:c, '

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'd, T. Ullrich, Superintend.cnt

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