ML20043B048

Updates 890330 Response to NRC Bulletin 88-010, Nonconforming Molded Case Circuit Breakers. Util Will Replace Unit 1 Inverter & Battery Charger Circuit Breakers within 30 Days After Receipt & QA Verification

ML20043B048
Person / Time
Site:	Point Beach
Issue date:	05/16/1990
From:	Boston J WISCONSIN ELECTRIC POWER CO.
To:	NRC OFFICE OF INFORMATION RESOURCES MANAGEMENT (IRM)
References
IEB-88-010, IEB-88-10, NUDOCS 9005240119
Download: ML20043B048 (3)

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POWER COMPANY '

231 W. MicNgon, Ro. Box 2046. Milwaukee, WI 53201 (414)221 2345 -

IMay -:16; [ 1990 -

3 U; S.sNUCLEAR REGULATORY COMMISSION

~ Document" Control Desk-Mail ~ Station.P1-137

, Washington, D. C.; 20555 Gentlemen: ,

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DOCKETS 50-266-AND 50-301 UPDATE TO RESPONSE'TO NRC BULLETIN 88-10

,' ; NONCONFORMING MOLDED-CASE CIRCUIT BREAKERS TPc l POINT BEACIL J411gLEAR PLANT. UNITS l'AND 2

'NRC. Bulletin 88-10 dated' November. 22,.1988 requested that-

Licensees"take actions to provide reasonable assurance that-

,' / molded-case circuit-breakers (CBs)" purchased for use 'in' safety-

related. applications without verifiable. traceability toithe circuit breaker manufacturer (CBM)1 perform their, safety e functions. ' Wisconsin Electric,' Licensee',irespondedito this

Bul~letin'in"a letter dated March 30, 1989.

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1 LItem)5-iofLthe March 30, 1989-letter addressed our commitment ~.to test or replace all safety-related-circuit, breakers which are not

>. traceable to CBMs. Wis'consin-Elect'ric stated that at least half'.

of theiidentified untraceable CBs-wouldfbe' replaced'or tested; before' start-up!from'the.first1 refueling / outage-beginning after' March:1,n1989. We further committed:to. replace or test;the:-

.remainingjuntraceab1'e:CBs. prior tofstart-up!from the'second-

/ refueling ~. outage after March 1' 1989. - ;The corresponding second refueling' outage'.for Unit'1'is nearing-completion, and.the Unit 2 second refueling;o'utage.is' currently. scheduled to be completed on November'16,J1990.

To date, we~have tested or'replacedgallLuntraceable'CDs with the'

, exception'of two.CBs in each ofl inverters 1DYO3,'2DYO3, DYOC, 1DYO4', 2DYO4, and DYOD and two CBs each in battery. chargers D107, u5 >

D108, . and D109,- for a total' of eighteen CBs.: We had anticipated' replacing,the'CBs in 1DYO3, DYOC,'1DYO4, DYOD, D107, D108, and-vy ' D109 by'the:end~of the Unit 1. spring 1990 refueling outage currently:being completed. We intend-to replace'the CBs in 2DYO3 6

and,2DYO4:by the end of the Unit 2 fall 1990 refueling outage.

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'NRC-Document' Control Desk 5 May 16,_1990 Page 2 We had taken-appropriate steps to fulfill our commitment to replace the remaining Unit i breakers during our current refueling outage by ordering replacement CBs for the inverters and: battery chargers in early 1990. CB nameplate data was used Jto ensure that correct breakers:were ordered.- These CBs were received-during the Unit 1 outage and appeared to be the correct breakers. However, when our plant maintenance personnel began replacing <these circuit breakers,-it was noted that the present

'AC'and DC CBs installed in the inverters and the DC CBs installed in the battery chargers contained auxiliary contacts'not included-in the replacement breakers . It was further-noted that the information on these auxiliary contacts wasonot' included on the CB nameplates. These auxiliary contacts provide-indication and alarm of breaker position.

We haveLdetermined that the auxiliary contacts are necessary_for plant operation and, thus,' replacement of the presently installed CBs cannot occur until CBs with the necessary auxiliary contacts can be procured. .In addition, while we have received the three replacement AC breakers for the battery chargers, we plan to delay their installation until the corresponding replacement DC

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breakers are received, since it is most efficient to replace'both breakers-internal to a given charger at the same, time. This.will also minimize the number of-times the chargers are removed from service.

The twelve untraceable breakers internal to the inverters are 1 General Electric' Type THJK 426-400 and Type TJJ 426-400 (one each

- in each inverter). We are currently. identifying an appropriate

manufacturer and installer.for the auxiliary contacts. Once that is; accomplished, we will establish a schedule for replacement of the currently installed CBs.

The three DC breakers internal to the battery chargers are Westinghouse Type MA2800. We are currently working with Westinghouse to obtain appropriate replacements with the .

, necessary auxiliary contacts. The earliest these breakers can be made available is during the last week of May; however, that availability date.is uncertain due to the manufacturer's possible difficulties in meeting quality assurance requirements during testing of the auxiliary contacts.

Tall eighteen breakers can be replaced while either or both units

.are operating. Accordingly, we are planning to replace the swing and Unit l' inverter and battery charger CBs within thirty days after receipt and quality assurance verification of appropriate replacement breakers. We will replace the Unit 2 inverter breakers-when practical after receipt but prior to start-up from the fall 1990 refueling outage, consistent.with our existing commitment.

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NRC Document Control Desk May 16, 1990 Page 3 We have reviewed the existing justifications for continued operation (JCOs) applicable to the untraceable circuit breakers not yet replaced. Each is still applicable, and we have modified the JCO conclusions to provide for continued Unit 1 operation until the existing CBs can be replaced with appropriate, traceable breakers.

Please contact us if you have any questions concerning this information.

Very ruly your s1

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' hn W. Boston Executive Vice President

& Chief Operating Officer Copies to NRC Regional Administrator, Region III NRC Resident Inspector Subscribed and sworn to before me this ) b th - day of May 1990.

yo b f krC c4 Notary Public, State of Wisconsin My Commission expires 6-27-90 .

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