ML17348B292

Part 21 Rept Re Potential Generic Component Defect in Asea/Abb Type RXMH2 Relays.Relays Utilized in Emergency Diesel Generator Bus Load Sequences.Info Gathering Underway. Customers Will Be Notified as Soon as Possible

ML17348B292
Person / Time
Site:	Turkey Point
Issue date:	08/12/1991
From:	Charlton M, Matthew Smith HUB, INC.
To:	Office of Nuclear Reactor Regulation
References
REF-PT21-91 NUDOCS 9112260255
Download: ML17348B292 (5)

Text

., ACCELERATED DI UTION DEMONS TION SYSTEM REGULATORY INFORMATION DISTRXBUTION SYSTEM (RIDS)

ACCESSION NBR:9112260255 DOC.DATE: 91/08/12 NOTARIZED: NO DOCKET FACIL:50-250 Turkey Point Plant, Unit 3, Florida Power and Light C 05000250 50-251 Turkey Point Plant, Unit 4, Florida Power and Light C 05000251 AUTH. NAME AUTHOR AFFILIATION CHARLTON,M. Hub, Inc.

SMITH,M. Hub, Xnc. R RECIP.NAME RECIPIENT AFFILIATION Office of Nuclear Reactor Regulation, Director (Post 870411

SUBJECT:

Part 21 rept .re potential generic component defect in ASEA/ABB Type RXMH2 relays. Relays utilized in emergency diesel generator bus load sec{uences.Info gathering underway.

Customers will be notified as soon as possible.

DISTRXBUTION CODE: XE19D COPIES RECEIVED:LTR t ENCL SIZE: /

TITLE: Part 21 Rept (50 DKT)

A NOTES D

RECIPIENT COPIES RECXPIENT COPIES ID CODE/NAME PD2-2 LA LTTR ENCL ID CODE/NAME PD2-2 PD LTTR ENCL D AULUCK,R INTERNAL: AEOD/DSP/ROAB OGCB11 NRR/DRIS/RVIB9D G FIL 01 RES/DSIR/EIB RGN1 RGN2 RGN3 RGN4 RGN5 SECY VANDERMEL EXTERNAL: INPO RECORD CTR NRC PDR NSIC SILVER,E D

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NOTE TO ALL "RIDS" RECIPIENTS:

PLEASE HELP US TO REDUCE WASTEI CONTACT THE DOCUMENT CONTROL DESK, ROOM Pl-37 (EXT. 20079) TO ELIMINATEYOUR NAME FROM DISTRIBUTION LIPID FOR DOCUMENTS YOU DON'T NEEDI TOTAL NUMBER OF COPIES REQUIRED'TTR 18 ENCL ml

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r~@RI liH1TED CONTROLS Tn: 12'991 4l 27'829 9483333 P.82 UNITED '-CONTROLS August 12> l991 Directori Office Of Nuclear Reactor Regulation US Nuclear Regulatory Commission Nashington, D.C, 20555

Subject:

Notification Of Potential Generic Detect, Per 10CFB Part 21 Notification By: United Controls Division Of Hub< Inc.

1554 Litton Drive Stone Mountain, Georgia 30083 Michael Char lton Director Of Quality 4 Technical Services (404) 496-0884 on August 10< 1991 at, 6 ~ 00 p.m. > the responsible officer at United controls was notified of a potential generic component defect found during an inspection of ASEA/ABB Type RXMH2 > Model RK223068-RA and RK223069"EA Relays at the Turkey Point Units 3 and 4, Sack rounds The sub)ect relays were purchased commercially in 1989, and dedicated by Un~@ed Controls for nuclear safety related application.

qualification method was seismic and environmental testing performed at, Hyle Laboratory. These relays are utilized in the Emergency Diesel Generator Bus Load Seguencers. Approximate3.y 300 relays are needed in the Sequencer Panels, The initial relay failure was found during performance of a pre-operational test, Stripping Relay 127ZS/3B1 short cirouited during this test Preliminary analysis appeared to indicate coil f ailure as the result of inadequate insulation at the 3unction point between the coil and inner winding terminal, Investigation into this f ailure continued in an effort to determine if this apparent manufacturing defect was an isolated incident< or a more generic condition i On August 10, 1991< representatives from ASIA/ASS Sweden performed an inspection of the sub)ect relays at the Turkey Point Plant. The inspection was to establish the adequacy of the insulation tape placement on the coil leads, Improper coverage of the coil lead can cause the coil to short circuit the majority of the wj.ndings, resulting in an over current condition which renders the relay inoperable, Out of six randomly chosen re1ays> all were found to possess inadequate tape coverage of the coil lead. Although the relays examined are functionally operable> they would bo sub)act to the same type cf short circuit failure mechanism.

4 DIVISIONOF HOB INC.

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FROMlUNl TED CONTROI 9 UNC TOi 9483333 UG f2'99'lF7PN 0829 P 93

~up, .l2, l>>l Page Two Corrective Action At the Turkey Point, Units 3 and 4, Seguencers have not yet been turned over to plant operations ~ The units are currently in a defueled status.

ASKA/ABB has stated that. there is currently no known limitations on how many RK223068 and 069's may be affected. At this time, it must be assumed all of these model number relays may be affected. ASEA/ABS has further stated that no other model relay Utilizes the same Coil design.

Therefoxe, the problem is limited only to the 068 and 069 Series.

United Controls is rapidly gathering information regarding othor oustomer s of dedicated safety related relays ef the sub)cot mOdel.

Notifications to these customers will be made as soon as reasonably achievable.

Prepared By; Date t S'//+f ~

Michael Char ton P.E.

Director of Quality a Technical Services Reviewed By ~ ~</<~~ DatO: +/~+ 9l Nart n Sm th President, Hub Eap MC/vb A~~d~nrirwwr rP ~>~~4++

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