U-601030, Part 21 Rept Re HPCS (Div III) Diesel Generator Exciter Leads Built by Beloit Power Sys & Supplied by Ge.Initially Reported on 870729.Temporary Repair Completed on 870813. Detailed Repair Plan Being Developed by GE

Part 21 Rept Re HPCS (Div III) Diesel Generator Exciter Leads Built by Beloit Power Sys & Supplied by Ge.Initially Reported on 870729.Temporary Repair Completed on 870813. Detailed Repair Plan Being Developed by GE

ML20238F772
Person / Time
Site:	Clinton
Issue date:	09/08/1987
From:	Hall D ILLINOIS POWER CO.
To:	Davis A NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
References
REF-PT21-87, REF-PT21-87-167-000 PT21-87-167, PT21-87-167-000, U-601030, NUDOCS 8709160338
Download: ML20238F772 (3)

Text

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U-601030 Ll6-87 ( 09-08 )-L 1A.120 ILLINDIS POWER 00MPANY CLINTON POWER STATION. P.O. BOX 678. CLINTON. ILLINOIS 61727 September 8, 1987 Docket No. 50-461 Mr. A. B. Davis 1 Regional Administrator

-Region III U.S. Nuclear Regulatory Commission 799 Roosevelt Road Glen Ellyn, Illinois 60137

Subject:

10CFR21 Defect 21-87-03: t HPCS (Division III) DIESEL GENERATOR EXCITER LEADS

Dear Mr. Davis:

i i

On July 29, 1987, Illinois Power' Licensing and Safety Department received a Potential 10CFR21 Defect or l Noncompliance Referral from the Illinois Power Nuclear Station Engineering Department concerning damaged HPCS (Division III) Diesel Generator Exciter Leads. Based on an evaluation of this matter, Illinois Power Company is providing the following information to the Commission in accordance with the requirements of 10CFR, Part 21.21(b)(3).

(i) D. P. Hall, Vice President of Illinois Power Company, by means of this report.

(ii) The basic component involved in this reportable defect is a Diesel Generator. .!

(iii) The Diesel Generator was built by Beloit Power Systems.

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(iv) The-nature of the defect involves generator field leads which run through the generator shaft from the ,

l field rectifier assembly to the main field. Diesel Generator exciter lead damage-was confirmed at the point where the exciter leads exit the generator 4 shaft. Chafing of the outer sleeve (cotton braid) was visually observed. The root cause of chafing was friction / rubbing by the movement of the leads with the generator shaft. This damage to the exciter leads resulted from the absence of materials such as Room Temperature Vulcanizing (RTV) to secure the leads in place inside the generator shaft.

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U-601030 L16-87 (09 -08 )-L 1A.120 Illinois Power Company has reviewed and evaluated the finding associated with the investigation of the defect / deficiency and has concluded that the matter represents a condition adverse to the safety of operation of the Clinton Power Station. If this defect / deficiency had gone uncorrected, it could have resulted in failure of the Division III Diesel Generator and loss of the High Pressure Core Spray j System (HPCS) during an accident condition. These i events could affect the integrity and safe shutdown of the reactor. On this basis, the matter was evaluated to be reportable under the provisions of  ;

10CFR21. l (v) Illinois Power Com any was notified of this potential defect /d ficiency in a letter received on j 1

July 23, 1987, from Energy Systems, a Division of '

Pelham, Inc.

(vi) The Division III Diesel Generator is the only generator at the Clinton Power Station built by Beloit Power Systems. The Division I & II Diesel i Generators were built by Ideal Electric and have a j different design. i l

(vii) On August 11, 1987, General Electric (supplier of j the Division III Diesel Generator) inspected the exciter leads and confirmed that damage existed at the pcint where the exciter leads exit the generator shaft. Following the inspection, in a meeting between Illinois Power, General Electric, and '

Stewart & Stevenson, it was agreed that Illinois Power would perform a temporary repair of the damaged portion of the exciter leads. This decision was reached based on a discussion that similar repairs have been successfully performed on generators of this type at Illinois Power's fossil power plants, and by Stewart & Stevenson at commercial diesel power plants. The temporary repair on the exciter lead was completed on August 13, 1987, under Temporary Modification 87-130. The temporary modification was evaluated by the Nuclear Station Engineering Department to be adequate for continued operation of the Division III Diesel Generator until the replacement of the exciter leads during the Fall Maintenance Outage currently planned for October 1987. General Electric is prepared to provide support to Illinois Power in performing the necessary repair work under General Electric's Nuclear Steam Supply System (NSSS) Warranty program.

A detailed repair plan is.being developed by General Electric and will be transmitted to IP upon completion.

U-601030 L16-87 (09 -08 )-L 1A.120 (viii) Letters of notification concerning this potential defect / deficiency were sent to purchasers / licensees by Energy Systems Division on behalf of Beloit Power System. .

1 Our evaluation of this reportable defect is available for your review at our offices. I trust this letter provides sufficient information for your review and assessment of this reportable defect.

Sincerely yours, I

'.Vice .President Hall RLC/ckc cc: USNRC Resident Office, V-690 3 Director of Inspection and Enforcement (3 copies)  !

INPO Records Center Illinois Department of Nuclear Safety 3 Energy Systems Division .

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