ML20085G284

AO BFAO-7323W:on 731011,vacuum Readings for Turbine Condenser Low Vacuum Switches PS-2-1A & PS-2-1D Exceeded Tech Spec Limit.Mechanisms of Switches Inspected,Switches Recalibr & Testing Frequency Increased

ML20085G284
Person / Time
Site:	Browns Ferry
Issue date:	10/19/1973
From:	Eric Thomas TENNESSEE VALLEY AUTHORITY
To:	Oleary J US ATOMIC ENERGY COMMISSION (AEC)
Shared Package
ML20085G286	List: ML20085G284 ML20085G288
References
BFAO-7323W, NUDOCS 8308240766
Download: ML20085G284 (2)

Text

_ _ _ _ _ _

. / --

i_4 O

O TENNESSEE CHATTANOOGA, VALLEY TENNESSEEAUTHOMITY it C~~3]\- 4 a74cn u i /A

~"

[ 7 r ~TH.

[ ] t

.4 .. U October 19, 1973 gjyggggy, PA AT N E F41.3 HIP

}

9 - l1 lr  %

?.0 ?Af

~ -

[/pt/) % %QWy O v xhT Mr. John F. O' Leary, Directo.

Directorate of Licensing

1. , h.." /8/g

{r <

Office of Regulation Q, ,

U.S. Atc=ic Energy Co.nission efA '

k'ashington, DC 205h5 / .- -'/

s ?N . .. .

Dear Mr. O'Icary:

TEI."JESSF:: VAIET. AUTHORITY - BRO'd::S FE3RY KUCLEAR Pl.CT U:!IT 1 -

DCCKET !!O. 50-259 - FACILITI CPERI. TING LICz::SE DPR AEXCEFAL OCCUR?KiCZ EEP0ET EFAO-7323k' t

The purpose of this report in to provide details concerning the malfunction of two turbine condenser low-vacuum evitchec in unit 1 I

at Browns Fern uclear n Plant on October 11, 1973 This occurrence i

was reported by telegrem to the Region II Directorate of Regulato n i Operations, Atlanta, Geor$ 1a, on October 12.

' a Descriptica of th: Incident n

During routine curveillance _ testing on October 11, turbine condenser low-vacuum switches PS-2-1A and 1D vere found to operate outside the technical specification cetpoint of greater than or equal to 23 inches of cercury ac specified in Table 3 1.a. Tne as-found vacuun readings vere 22.8 and 22 3 inches of mercury, respectively. The svitenes are arranged in a one out of two taken twice logic in the Reactor Protection System. The other two channels were tested and found to operate caticfactorily; and, if required, the RPS logic would have performed its intended function. The reactor vac in a cold shutdovn condition. ,

Investigaticn and Corrective Action The nochanisms of_thece Earksdale vacuun switches, model DIT-H18SS,  !

vere inspected for binding, misalignment, cr other irregularitics. '

/h Nonc vere found. The cvitchen vore recalibrated and then functionally tected ccvercl tines to encure repeatcbility. A functionnl testing

f. frec,uency of once every two veeks has been initiated for all four p.

hYl$8lk6g . CV A' 7772 COPY SEN1' REGION

1

. .. - .-.l

. 'w) L) l 2

1fi . John F. O'Ioag Cetober 19, 1973 TEli:!ESSEE VALUTI AUTECRITY - 3ROU:!S ICERY ITUCLEAR PLCT U? LIT 1 -

DOCKET I!C. 50-259 - FACILITY OPERATI!!G LICE!iSE DPR AE'iCPaL OCCURP3::C0 IEPORif EFAO-7323U switchec of thic RP3 function and vill be continued until three consecutive tecto prove satisfactory perfonnance. At that time, the ori Cinal tect schedule of once a conth will be recumed.

Very truly yours, TE:!' E3SEE VALIIY f.UTI:C21~'Y f /,/

(. 4/

'/

. /"%

/ E. F. Thomas

/.

Director of Power Productica CC: l'r. ;iornan C.1:cceley, Director Region II Re6ulatory Cperations Office, USAEC 230 Peachtree Street, I"J.

.t'.ca:n, Cacrgic 30303 I

i 0

pe-

_ _ . _ __,