ML20023D810

Response Opposing W Eddleman Proposed New Contention 161 Re DS-416 Circuit Breakers.Proposed Contention Should Be Rejected Or,Alternatively,Deferred Pending W Eddleman Review of Proposed Design Change.Certificate of Svc Encl

ML20023D810
Person / Time
Site:	Harris
Issue date:	05/31/1983
From:	Oneill J CAROLINA POWER & LIGHT CO., SHAW, PITTMAN, POTTS & TROWBRIDGE
To:	Atomic Safety and Licensing Board Panel
References
ISSUANCES-OL, NUDOCS 8306030336
Download: ML20023D810 (8)

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UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION 00LKETED UMOC BEFORE THE ATOMIC SAFETY AND LICENSING BOARD 33 gja-2 v.0.55 In the Matter of )

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CAROLINA POWER & LIGHT COMPANY ) Docket Nos. 50-400 OL AND NORTH CAROLINA EASTERN ) 50-401 OL MUNICIPAL POWER AGENCY )

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(Shearon Harris Nuclear Power )

Plant, Units 1 and 2) )

APPLICANTS' RESPONSE TO INTERVENOR EDDLEMAN PROPOSED CONTENTION 161 (DS-416 CIRCUIT BREAKERS)

By a pleading dated May 7, 1983, as supplemented on May 34, 1983, Intervenor Wells Eddleman has supplemented his petition to intervene by proposing a new Contention 161 which alleges as follows: ,

Applicants have not demonstrated that the Harris nuclear reactors can be safely shut down when shut-down is required, because of defects and possible malfunction of Westinghouse DS-416 circuit breakers used in the safety related shutdown systems at Harris.

For the reasons set forth below, Applicants Carolina Powar & Light Company and North Carolina Eastern Municipal Power Agency submit that Contention 161 must be rejected for failure to state suf-ficient basis for the allegations made.-1/ Alternatively, the Board should defer its ruling on Contention 161, to allow Mr. Eddleman a period of time (thirty days) within which to review the proposed design change to the DS-416 reactor trip switchgear undervoltage attachments, and thereafter to amend, modify or withdraw his proposed Contention 161.

1/ Applicants are not addressing Mr. Eddleman's arguments for good cause for a late filed contention and do not here challenge the timeliness of the proposed contention.

8306030336 930531

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l BACKGROUND i

L .On March 31, 1983, Westinghouse Electric Corporation

(" Westinghouse") informed the NRC of the potential for' inter-

-mittent malfunction of reactor trip switchgear that employs the DS-416 undervoltage (UV) trip device. Pending further.inves-tigations, operating plants utilizing the identified undervoltage trip device were advised that control room operators.should actuate the manual reactor trip switch at the Main' Control Board when a demand for an automatic undervoltage trip is observed.

See letter from E. P. Rahe, Manager, Westinghouse Nuclear Safety Department, to R. C. DeYoung, Director, Division of.NRC Inspection and Enforcement, dated March 31, 1983 (Attachment A).

On April 12, 1983, Westinghouse informed the-Harris Project Staff at Carolina Power & Light Company -("CP&L") of the identified problem. See letter from R. L'. Whitney, Westinghouse, to L. I. Loflin, CP&L, dated April 12, 1983 (Attachment B). On April 20, 1983, Westinghouse reported the problem with the undervoltage attachments to the_DS-416 reactor trip switchgear to the NRC, pursuant to 10 C.F.R. Part 21 (for operating plants) and pursuant to 10 C.F.R.

S 50.55 (e) (for plants under construction). This report to the NRC was confirmed in correspondence with CP&L on April 21, 1983. See letter from R. L. Whitney to L. I. Loflin dated April 21, 1983.

(Attachment C). In Westinghouse's April 21, 1983 letter, a design discrepancy was described in the undervoltage attachment to the DS-416 reactor trip switchgear. The groove in the shaft receiving the retaining ring was not increased in width to be consistent

with an earlier retaining ring design change.. The new retaining ring is wider than the original design and does not properly seat in the existing grooves. Westinghouse committed to replace the undervoltage attachments on DS-416 reactor trip switchgear supplied by Westinghouse. The new attachments have modified (widened) grooves to accommodate the new retaining rings. Further-more, Westinghouse is developing and will implement a procedure for installation of the new-attachments on DS-416 reactor trip switchgear in the Harris plant, which will ensure proper alignment.

and interface of the attachment with the breaker trip shaft.

On May 26, 1983, Applicants submitted to the NRC an interim report on the identified problem with the undervoltage attachments to the DS-416 reactor trip switchgear pursuant to 10 C.F.R. S 50.55 (e) and 10 C.F.R. Part 21 (Attachment D). This report commits to implement the design change to correct the identified design deficiency. Applicants are also considering the implementation of another design change, currently undergoing industry review, which would provide redundant actuation of an undervoltage trip signal by activation of both the undervoltage attachment and the shunt coil attachment on the DS-416 reactor trip switchgear.

RESPONSE TO CONTENTION 161 Mr. Eddleman offers as basis for Contention 161 a report in INSIDE NRC of Westinghouse's April 20, 1983 report to the NRC.

But Contention 161 is far too sweeping an allegation to be supported by the identification of a design problem with the undervoltage attachment to the reactor trip switchgear. There is

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-4 no basis--for.the assertion that " Applicants have not demonstrated,that the Harris nuclear reactors can'be safely-shut down when shutdown is required, because of defects-and lpossible malfunction of West'inghouse DS-416 circuit breakers used.in the safety-related shutdown. systems at Harris." (emphasis supplied). The identified problem was only with an. automatic trip of the circuit breaker when an undervoltage signal was received. The immediate corrective action recommended by Hestinghouse for operating plants was to instruct reactor operators i

to initiate a manual shutdown (which would involve a trip of the DS-416 circuit breaker) . There has been no identified problem with the shutdown capability of nuclear reactors'using the DS-416 reactor trip switchgear-(i.e. with the circuit breaker actually tripping) , and the INSIDE NRC article cited by Mr. Eddleman as basis certainly does not support such an allegation. This,-

o'f course, is an extremely important distinction. Thus, while Mr. Eddleman has admittedly pointed to an identified design problem, his contention goes much too far and must be rejected for lack of any basis.

Applicants appreciate'that Mr. Eddleman did not have the correspondence attached to this pleading and' adequate technical information with which to assess the import of the deficiency i' identified in the trade press article. Applicants are willing to stipulate'that they will not raise timeliness as an objection to a revised contention filed by Mr. Eddleman within thirty days, if he so chooses, based on the information contained in this Response.

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5-Under the circumstances, Applicants'would not object to_the ,

Board's deferr'ing a huling on Contention 161, until such time as Mr. E'ddleman has had an opportunity to review Applicants' Response hereto,i similar to the procedure. adopted by the' Board for control' room design contentions. .Under such a procedure, Mr. Eddleman would have thirty days within which to amend, modify or withdraw Contention 161. Applicants and the NRC Staff would have fifteen and twenty days, respectively, to l reply. .

Counsel to Applicants discussed this Response to' proposed Contention 161 with Mr. Eddleman by telephone on-May 31, 1983. Mr. Eddleman authorized counsel to represent-to the. Board;that'if.the Board does not decide that Contention 161'is admissible as' written, he has no objection to adoption of the' procedure outlined by Applicants, which would allow him.

thirty days within which to review Applicants' technical response and to amend, modify or withdraw Contention 161, as he chooses, l

after such review.

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H. O'Neill, Jr.

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John AW PITTMAN, POTTS & TROWB.itIDGE 1 M Street, N.W.

Washington, D.C. 20036 (202) 822-1090 Richard'E.-Jones Samantha Francis Flynn CAROLINA POWER & LIGHT COMPANY P.O. Box 1551 Raleigh, North, Carolina 27602 Counsel for Applicants l Dated: May 31, 1983 , ,

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May 31, 1983 UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION BEFORE THE ATOMIC SAFETY AND LICENSING BOARD In the Matter of )

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CAROLINA POWER & LIGHT COMPANY ) Docket Nos. 50-400 OL AND NORTH CAROLINA EASTERN ) 50-401 OL MUNICIPAL POWER AGENCY )

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(Shearon Harris Nuclear Power )

Plant, Units 1 and 2) )

CERTIFICATE OF SERVICE I hereby certify that copies of " Applicants' Response to Intervenor Eddleman Proposed Contention 161 (DS-416 Circuit Breakers)," dated May 31, 1983 are being served to all those on the attached Service List by deposit in the U.S. Mail, first class, postage prepaid, this 31st day of May, 1983.

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Dated: May 31, 1983 i

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UNITED STATES OF AMERICA NUCLEAR REGULATORY COMMISSION BEFORE THE ATOMIC SAFETY AND LICENSING BOARD In the Matter of )

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CAROLINA POWER & LIGHT COMPANY ) Docket Nos. 50-400 OL "

AND NORTH CAROLINA EASTERN ) 50-401 OL MUNICIPAL POWER AGENCY ) ,

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(Shearon Harris Nuclear Power )

Plant, Units 1 and 2) )

SERVICE LIST J ees L. Kelley, Esquire John D. Runkle, Esquire Atanic Safety and Licensing Board Cm_=_arvation Counc:tl of North Carolina '

U.S. Nuclear Regulatory Cewmi=sion 307 Granville Road Washington, D.C. 20555  % l Hill, North Carolina 27514 Mr. Glenn O. Bright M. Travis Payne, Esquire Atanic Safety and Lie-ig Board Edelstein and Payne U.S. Nuclear Regulatory renmiasion P.O. Box 12643 l Wamhi5 ton, D.C. 20555 Raleigh, North Carolina 27605 l

Dr. Janes H. Carpaear Dr. Richard D. Wilson Atanic Safety and Limnsing Board 729 nw*ar Street U.S. Nuclear Regulatory Cemni_ssion Apex, North Carolina 27502 I Washington, D.C. 20555 Mr. Wells Eddlenan Charles A. Barth, Esquire 718-A Iredell Street Myron Kannan, Esquire Durhan, North Carolina 27705 Office of Executive Iegal Director U.S. Nuclear Regn1

• mry Cewmiasion Richard E. Jones, Esquire Wanhim3 ton, D.C. 20555 Vice President & Senior Counsel Carolina Power & Light Conpany Docketing and Service Section P.O. Box 1551 Office of the Secretary Raleigh, North Carolina 27602 U.S. Nuclear Regulatory Ccmnission Washington, D.C. 20555 Dr. Phyllis Ictchin 108 Bridle Run Mr. Daniel F. Pead, President Chapel Hill, North Carolina 27514 Chapel Hill Anti-Nuclear Group Effort P.O. Box 524 Chapel Hill, North Carolina 27514

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Deborah Greenblatt, Escuire 1634 Crest Ecad Raleigh, Nc: h Carolina 27606 Bradley W. Jcces, Esg'4re U.S. Nelaar Regulatory c=4 =sion ,

Region II 101 Marrietta Street Atlanta, Gecm:r!.a 30303 R*ha- G.. Miller, Esquire .

Atcznic Safety and Licensing Board Panel .

e U.S. Nuclear Regulatory C 4==icn -

Wa=hireten, D.C. 20555 Karen E. Long, Esq.

Staff Attorney Public Staff - NCUC P.O. Box 991 Raleigh, North Carolina 27602 e

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3 Attachment A 1A .

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• m "i i 5222 Ecc:n: 2rsoration Divisions NS-E?R-2744 March 31, 1983 Mr.'R. C. DeYoung, Directer Division of Inspection and Enforcement U.S. Nuclear Regulatory Ccmmission Phillips Building 7920 Norfolk Avenue Bethesda, MD 20014

Dear Mr. DeYoung:

This is to confirm the telephone conversation of March 31, 1983 between R. A. Wiesemann and R. B. Miller of my staff and Mr Gecrge Lanik of the NRC. In that conversation, I reported that Westinghouse had informed its cperating utility custcmers of the potential for intermittent malfunction of reacter trip switchgear that employs the D5-416 undervoltage (UV) trip device. To minimize the potential on any reac:cr trip switchgear utilizing this device, Westinghouse has reccmmended inspections as discussion below.

Westinghouse recently has been advised by one utility that one of the two main reactor trip breakers at each plant did not trip during 4 preplanned testing. At one plant, three malfunctions occurred out of a total of 116 cycles. At the other plant, only one malfunction occurred in over 400 cycles. The reTiability of the D5-416 UV device is supported by functional factory tests, vendor qualification programs, and periodic surveillance testing at operating plants in which no malfunctions have been reported. Therefore, these malfunctions are considered to be random in nature.

The owner of the two plants involved, in close cooperation with Vestinghouse, has removed the UV trip device from one of the reacter trip breakers that malfunctioned and returned it to Westinghouse for a detailed examination to determine, if possible, the reason for such malfunctions.

Based upon a review at the piant site and at Westinghouse, the following have been identified as the potential factors for the reported occurrences.

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a. Maruf acturing variations permitted interference between the moving cor'e and the reiler bracket on one of the UV devices unich a:: pears to be related to the intermittent malfunctions. A further facter may have been lack cf side-to-side clearance of the roITer bracket.

b. Lack cf minimum ga:: between the UV trip reset lever and the breaker trip bar pin a:: pears :: be related tc :ne malfuncticn :f tne secen UV device.

To determine if other 05-416 UV trip devices installed in the field are also susceptible to similar malfunctions, the dimensions identified in Figure 1 must be verified. Westinghouse is requesting that the utilities listed in Table 1 make these dimensional measurements and provide us with the results for our further evaluation of this potential unreviewed safety question.

Until the dimensions are verified, Westinghouse has further reccamencec that the control rocm operators actuate the manuai reactor trip switen at the Main Control 5 card when a demand for an autcmatic reacter trip is observed. If the installed devices meet all the criticai dimensions identified in Figure 1, the recommendation for manual reacter trip may be removed. However, if either the UV trip device or the trip bar is found to be out of tolerance with respect to the dimensions identified in Figure 1, Westinghouse recer: rends that replacement devices be installed.

Westinghouse ocerating utility custcmers are being informed that Westinghouse is reporting this to the NRC as a potential unreviewed safety question under 10CFR50.59 for operating plants. Fcr piants under construction Westinghouse is requesting more information to determine if a significant deficiency exists.

If you have any additional questions, please contact me or Clarence Draughon of my staff at (412) 374-6761.

Sincerely,

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E. P. Rahe, Manager Nuciear 5afety. Department

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..l CQL-7343 I Attachment B Westinghause Water Reactor war C:Sa=s N'so Electric Corporation Divisions m 33 prs:urannsnama sm Mr. L. I. Loflin, Manager April 12,1983 Harris Project Engineering Carolina Power & Light Company P. O. Box 101 New Hill, NC 27562

Dear Mr. Loflin:

CAROLINA POWER & LIGHT COMPANY SHEARON HARRIS NUCLEAR POWER PLANT DS-416 Reactor Trio Breakers Westinghouse was recently informed by a utility that one Model DS-416 main reactor trip breaker at each of two plants did not trip during preplanned testing of the undervoltage (UV) trip function.

Based upon a review at the plant site and at Westinghouse, the following items have been identified as the factors potentially involvecf in the reported occurrences:

a. Manufacturing variations permitted interference between the moving core and the roller bracket on one of the UV devices.

A further factor may have been lack of side-to-side clearance of the roller bracket.

b. Lack of minimum gap between the UV trip reset lever and the

, breaker trip bar pin appears to be related to the malfunction l of the second UV device.

To determine if any DS-416 UV trip devices installed at Harris 1 and 2 are susceptible to similar malfunctions, the dimensions identified in the attached Figure 1 must be verified. Westinghouse is requesting that you l

make those ' dimensional measurements for each DS-416 reactor trip breaker and provide us with the results for our further evaluation.

In addition, an estimate of the number of duty cycles experienced by each DS-416 reactor trip breaker and a report of failures experienced, if any, are also requested..

On March 30, 1983, the Westinghouse Water Reactor Divisions Safety Review Comittee reviewed this specific D5-416 issue and detennined that this item

/- represents a potential unreviewed safety question under 10CFR50.59 for RE0'D APR191983

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2- CQL-7343 operating plants. Westinghouse is currently involved in dialogue with the Nuclear Regulatory Commission on the subject of breaker malfunction in the reactor protection system. Westinghouse, therefore, notified the NRC of this issue both orally and in writing on March 31, 1983. A copy of the Westinghouse letter to the NRC, NS-EPR-2744, is attached.

Your response is requested by April 29, 1983.

If you have any questions, please do not hesitate to contact the undersi'gned.

Very truly yours, WESTINGHOUSE ELECTRIC CORPORATION

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. Carolina Power & Light Project RLW:bmf Attachment D. J. Scanlon, Ebasco, IL II J. L. Willis, CP&L Site, IL, lA N. J. Chiangi, CP&L Site, IL 1A J. J. Sheppard, CP&L, IL, lA L. H. Martin, CP&L, IL, l A R. M. Parsons, CP&L Site, IL, lA G. L. Forehand, CP&L Site, IL, l A E. M. Harris, CP&L Site, IL 1A J. F. Halifax, W Raleigh, IL E. Four, W Sales (Hillside), IL C. L. McKEnzie, CP&L, il lA 4

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Water Reactor wc:ev sme omsien estinghouse Electric Corporation Divisions gg3 esu;- cerse.a,a w Mr. L. I. Loflin, Manager April 21,1983 Harris Project Engineering Carolina Power & Light Company -

Ref: CQL-7343 P. O. Box 101 New Hil1, NC 27562

Dear Mr. Loflin:

CAROLINA POWER & LIGHT COMPANY SHEARON HARRIS NUCLEAR POWER PLANT 05-416 Reactor Trio Switchgear This is to notify you that on April 20, 1983, Westinghouse advised the Nuclear Regulatory Comission of the potential for misoperation of DS-416 reactor trip switchgear undervoltage attachments. This was reported to the NRC under 10CFR21 for operating plants, and under 10CFR50.55(e) for plants under construction.

Westinghouse previously advised you of the potential for misoperation of these attachments based on reported malfunctions at one plant during testing.

With the referenced letter Westinghouse requested information from you rela-tive to dimensions of several clearances in the attachment to aid in our evaluation. The Westinghouse evaluation has concluded that deviations from the recommended clearances could increase the potential for misoperation of the attachment, thereby creating a condition wherein the reactor trip switchgear might not open on automatic demand from the reactor protection system.

After the earlier notification (CQL-7343), Westinghouse advised the opera-ting plants on April 15, 1983, of an additional misoperation of another 05-416 undervoltage attachment. Investigation of this event revealed a missing retaining ring on one of the two undervoltage attachment pivot shafts (shown in Attachment 1). This allowed the pivot shaft to move laterally such that one end came out of its guide hole in the frame of the undervoltage attachment, and did not permit the. attachment to operate on demand. A missing retaining ring was also identified at another plant. No misoperation of that attachment had been reported.

The Westinghouse evaluation of the retaining ring issue revealed a discrepancy in design. THe groove in the shaft receiving the retaining ring was not increased in width to be consistent with an earlier (1972) retaining ring -

design change. The new retaining ring is wider than the original design,and

L. I. Loflin CQL-7360 does not seat properly in the existing grooves. This discrepancy increases the potential for misoperation of the DS-416 undervoltage attachment, thereby creating a condition wherein the reactor trip switchgear might not' open on automatic demand from the reactor protection system.

Corrective Actions

1. Westinghouse is committing to its utilities to replace the undervoltage attachments on DS-416 reactor trip switchgear supplied by Westinghouse for its. Nuclear Steam Supply Systems.

2. The new attachments have modified (widened) grooves to accommodate the new retaining rings.

3. Manufacturing drawings have been revised and quality control procedures modified to 1ssure that critical design dimensions are maintained during manufacture.

4. Furthermore, Westinghouse is developing and will implement a procedure for installation of the new attachments on DS-416 reactor trip switch-gear in the Harris plant. This field installation procedure will provide for proper alignment and interface of the attachment with the breaker trip shaft.

Until replacement undervoltage attachments can be fabricated, shipped, and properly installed at operating plants, Westinghouse has recommended the following be verformed:

a. Assure that control room operators are alerted to the potential for misoperation of the reactor trip switchgear due to possible malfunction of the undervoltage attachments. .

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b. Re-emphasize to the control room operators the indications available i

to detect failure of the rods to insert into the core following a deaand signal from the automatic protection' system.

c. Re-emphasize to the control room operators the manual reactor trip 1

options available in the existing emergency operating procedures.

These procedures contain diverse methods of tripping the reactor which do not rely on the undervoltage trip attachment.

d. Visually verify after operation of the reactor trip switchgear that retaining rings are located on the grooved ends of the two under-voltage pivot shafts identified in Attachment 1. This will provide increased confidence that the shaft will not disengage, and that the attachment will be operable for the next trip demand. After installa-l tion of the replacement DS-416 undervoltage attachments, the require-ment to visually verify the presence of retaining rings after opera-tion of the reactor trip switchgear can be eliminated.

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- 3- CQL-7360 If you require additional information on this, please contact me.

Very truly yours.

WESTINGHOUSE ELECTRIC CORPORATION R. L. Whitn y, Mahager Carolina Powe.r.& Light Project RLW:bmf cc: L. I. Loflin, CP&L Site, 2L R. K. Matzelle, Ebasco, il D. J. Scanlon, Ebasco, IL J. L. Willis, CP&L Site, IL N. J. Chiangi, CP&L Site, il J. J. Sheppard, CP&L, IL L. H. Martin, CP&L, IL R. M. Parsons, CP&L Site, IL J. F. Halifax, W Raleigh, IL E. Four, W Sales (Hillside), IL C. L. McKenzie, CP&L lL l

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P. O. Box 101,-New Hill, N. C. 27562 May 26, 1983 Mr. James P. O'Reilly NRC-73 United States Nuclear. Regulatory Commission Region II 101 Marietta Street, Northwest (Suite 3100)

Atlanta, Georgia 30303 CAROLINA PO~a'ER & IIGHT COMPAhT SHEARON HARRIS SUCLEAR POWER PLANT 1986-90.-_900,000 KW - UNITS 1 & 2 MAIN REACIOR TRIP BREAKERS, SHOP ORDER 386, ITEM 130

Dear Mr. O'Reilly:

Attached is an in: erin report on the subject item which was deemed reportable per the provisions of 10CFR50.55(e) and 10CFR, Part 21, on April 27, 1983. CP&L is pursuing this matter, and it is currently projected that corrective action and submission of the final report will be accocplished by June 30, 1984.

Thank you for your consideration in this matter.

Yours very truly, Y

R. M. Parsons-Project General Manager Shearon Harris Nuclear Power Plant J

RMP/sh Attachment cc: Mr. G. Ma.well (NRC-SHNPP)

Mr. R. Prevatte (NRC-SHNPP)

Mr. V. Stella (NRC) e e

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CAROLINA POWER & LIGHT COMPANY-SHEARON EARRIS NUCLEAR POWER PLANT i

UNITS 1 AND 2 i-i INTERIM REPORT SHNPP MAIN REACTOR TRIP BREAKERS 4 ITEM 130

MAY 24, 1983

! REPORTABLE UNDER 10CFR50.55(e)

REPORTABLE UNDER 10CFR21

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SL'BJECT : SHNPP Units 1 and 2 Main Reactor Trip Breakers, Westinghouse Model DS-416 purchased under NSSS contract with Westinghouse NY-435002, Shop order 386.

ITEM: Misoperation of the undervoltage attachments.

SL'PPLIED BY: Westinghouse Electric Corporation Switchgear Division.

NATURE OF DEFICIENCY: A design discrepancy exists concerning a retaining ring on the undervoltage attachment pivot shaf ts.

Specifically, a design change increased the width of a retaining ring, while the groove in which the retaining ring seats, was not changed. This allows improper seating of the retaining ring. The result is that the retaining ring may detach itself from the pivot shaft with the potential for misoperation of the undsrvoltage attachment.

DATE PROBLEM OCCURRED: on April 12, 1983, Westinghouse informed CP&L (CQL-7343) of a potential problem concerning minimum gap clearances on the same item. On April 21, 1983, Westinghouse informed CP&L (CQL-7360) of a potential problem concerning a retaining ring design discrepancy on the undervoltage attachment.

DATE PROBLEM REPORTED: On April 18, 1983,- CP&L (Mr. N. J. Chiangi) notified the NRC (Mr. C. Hehl) that this item was potentially reportable. On April 27, 1983, CP&L (Mr. N. J.

Chiangi) notified the NRC (Mr. A. Hardin) that this item was reportable under 10CFR50.55(e) and 10CFR21. ]

SCOPE OF PROBLEM: This deficiency involves two Unit 1 and two Unit 2 Reactor Trip Breakers and two Unit 1 and two Unit 2 Reactor Trip Bypass Breakers.

SAFETY DIPLICATIONS : The potential for misoperation of the undervoltage attachment could create a condition wherein the reactor trip breakers might not open on automatic demand from the reactor protection system. This could prevent a safe shutdown of the reactor unless prompt operator action is taken to " manually" trip the reactor.

REASONS DEFICIENCY REPORTABLE: This item is reportable because the deficiency reported may affect the ability of safety rel:ted equipment to perform its intended function.

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CORRECTIVE ACTION: 1. Westinghouse has. committed to replacing the undervoltage attachments which: includes a replacement pivot shaf t with wider grooves. to accommodate the new retaining ring. Westing-house is developing new procedures for the installation and proper alignment and interface of this attachment.with the breaker trip .

shaft.

PREVENTATIVE-ACTION: 1. ' Westinghouse has revised manufacturing drawings and quality control procedures to assure that critical design dimensions are maintained during manufacture.

2. To prevent trip breaker failure as a result of any undervoltage attachment malfunction, CP&L is reviewing industry information as a

. precursor to initiating a design ~ change for the automatic du-l trip operation by activating-both the undervoltage attachment and the shunt coil attachment on receipt of an automatic undervoltage signal from the reactor protection system.

FINAL REPORT: CP&L expects to complete the corrective action plan and submit a final report by June 30, 1984. .

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