ML20086L256

Telecopy AO 74-15A & 15B:on 740324,setpoint Shift Found on Switches dPIS-2-2-129B & TS-2-12-99.Caused by Instrument Drift.Switches Recalibr,Tested & Returned to Svc

ML20086L256
Person / Time
Site:	Peach Bottom
Issue date:	03/25/1974
From:	Ullrich W PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I)
Shared Package
ML20086L252	List: ML20086L249 ML20086L256
References
AO-74-15A, AO-74-15B, NUDOCS 8402080024
Download: ML20086L256 (2)

Text

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f t Peach Potton Atomic ro.:er Station

. Delta, Penncylvnnia 3

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17314' di g

Ihrch 25,1974

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Mr. J m.ec P. O'Reilly, Director a Unit <. : Ct t ec Atc~i c Ener; y Co.niccion I DirNtcr"te of Eeculatory Operations t.71 Pa r': Ave: 2e -

/ing of Fruccia, Pennsylvania 19406 -5 S :b ice + : Ab-or ,1 Ocevre.,en 2h-IIc :r I:ctifiention 3 J

Confircin; ty convencation with Mr. R. A. Feil, A.E.C. Region I l Eegulatory Operationc Office on March 25, 1974. 1 JE --

Reference:

Licence I! umber DPR 44, Amendment I! umber 1

-i A. Technical Specification Table 3 2.3 j B. Technical Specification Table 3 2.A -

Report I!o. : 50-277-74-15A and 15B .

i Repert Date: March 25, 1974 '

4 Occurrence Date: ' .rch 24,1974 .i Facili t;, : icach Ecttom Atomic Pc.ter Station R. D.1, Delta, Pen:.cylvania 17314 -

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Identification of Occurrence:

A. Setpoint chift on dPIS-2-2-1293.

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B. Setpoint shift on TS-2-12-99 ni d.

Conditienc Pridr to Occurrence: '2 Plant shutdown. m

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Deccription of Occurrence: --

A. During inctrument curveillance testing, dPIS-2-2-1293 tripped at 0.45 paid inctcad of within the Tech Spec limits of 0 5 to 15 pcid. -

B. During inctrumentg curveillance testing, TS-2-12-99 tripped at "

approximately 142 F instead of within the Tech. Spec limit of 1 140 F. h Decignation of App rent Cauce of Occurrence:

, . . _i h.

.tnability of culte.n to hold precice cetpoints. This type of W switch is precently under ctudy as to proper ap^olication. '"

B. Obvious cetroint drift.  :

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Ana,yc1c

. of Occurrcnce: -

A. The setpoint chift of dPIS-2-2-129; would not have defeated the logic to produce the required correct loop celection. The j remaining cultenes in thic logic were t ithin specifications and it-would have produced the proper action.

B. The cetroint chift of TS-2-12-99 was minor and would not have teacurnb}y affected plant or public safety. 1 1

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840208002405000277 740403 p Hq 1 P,DR ADOCK m ot?y 7]

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s 6 o J Cfr " r. i v e /.c t i on :

Ea t;. c.;; tel c - re reculibrated, tecte:1 n:ul r, turned to cervice.

u11;,+._iti;l -::.tchen ar. alreaci.'t part of the Group being

n. 3 9r 2 ., .

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B. Tho .t <.  : turo rcitch will be invcrtic,ted becauce there is inelication of previouc cetroint drif t.

Fail: e P-ta:

A. The pIrticular c.: itch 1;,0 no previouc hictory of failure, but thic t:~e of r.: itch + :n failed ceven timec previoucly in variouc rervicec.

B. The tcrporature c.zitch h c been found outcide of crecc previoucly,,but that failure ,:ac found to be due to cet ting the c.: itch tea cloca to the decired limit. See Abnormal Occurrence Ecport dated October 1, 1973

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R. G. Fleiccir.,nn, II .

Peach Ecttom Atomic Power Station l

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