ML20096G042
| ML20096G042 | |
| Person / Time | |
|---|---|
| Site: | Nine Mile Point  |
| Issue date: | 08/20/1984 |
| From: | Mangan C NIAGARA MOHAWK POWER CORP. |
| To: | Starostecki R NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION I) |
| References | |
| (NMP2L-0134), (NMP2L-134), 55(E)-84-25, NUDOCS 8409100322 | |
| Download: ML20096G042 (3) | |
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T N3M NBAGARA MOHAWK POWER CORPORATION /300 ERIE BOULEVARD WES T, SYRACUSE. N Y.13202/ TELEPHONE (315) 474-1511 August 20, 1984 (NMP2L 0134)
Mr..R. W..Starostecki, Director-U.S. Nuclear Regulatory Commission Region I.
Division of Project and Resident Programs 631 Park Avenue
. King of Prussia, PA 19406
- Re: Nine Mile Point Unit 2 Docket No. 50-410
Dear Mr. Starostecki:
Enclosed is a final report in accordance with 10CFR50.55(e) for the problem concerning motor control centers' wiring deficiencies. This problem was reported via telecon to your staff on July 19, 1984 Very truly yours, Vice President Nuclear Engineering & Licensing AFZ:ja-
. Enclosure
.xc: Director of Inspection and Enforcement U.S. Nuclear Regulatory Commission b
Washington, DC 20555 Project File (2)
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NIAGARA M0 HAWK POWER CORPORATON NINE MILE POINT UNIT 2 DOCKET NO. 50-410 Interim Report for the Problem Concerning Gould Motor Control Center (MCC)
(55(e)-84-25)
Description of the Problem Deficiencies have been identified in QA Category I Motor Control Center wiring due to poor workmanship. Specifically, the following deficiencies have been found:
1.
Insufficient wire projection in terminal lugs.
2.
Broken or nicked strands of wire.
3.
Insufficient wire lengths causing stress at wire / terminal lug interface points.
4.
Wiring not securely clamped.
The specific equipment affected are:
2EHS*MCC101 2EHS*MCC301 2DMS*MCCAl 2EHS*MCC102 2EHS*MCC302 2DMS*MCCB1 2EHS*MCC103 2EHS*MCC303 Analysis of Safety Implications The above-stated deficiencies could represent potential problems during a design basis event such as:
1.
Wire could pull out of lug resulting in control circuit discontinuity.
2.
Lug and/or wire could fatigue and break.
3.
Wire could catch on an object and break the wire or lug.
These wiring deficiencies could have prevented the Motor Control Centers from performing their design function, thus resulting in loss of power and/or controls of safety-related systems (e.g., service water system, standby liquid control, main steam system, reactor water cleanup and residual heat removal).
Therefore, the problem were to remain uncorrected, it could have adversely affected the safe operation of the plant.
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-Q Corrective Action The following corrective action will be taken:
1.
Insufficient wire projection: Construction shall cut off the old termination and reterminate the wire using PIDG lugs in accordance with the manufacturer's recommendation. Cable ties may be cut as required to provide sufficient slack. Wire shall be reconnected and supported as required.
2.
Broken or nicked strands of wire: Construction shall remove the existing lugs up to the point of the broken strand. The wire shall be reterminated using " AMP" PIDG lugs in accordance with the manufacturer's recommendations.
3.
Insufficient wire lengths:
If sufficient wire is not available to
. provide enough slack to eliminate the stress points after all ties have been cut, Construction shall use wire supplied by the vendor as a replacement part. The old wire shall be removed and the required length of new wire shall be cut, terminated with " AMP" PIDG lugs in accordance with the manufacturer's recommendation and tied and clamped as outlined in Item 4 below.
4.
Wiring not securely clamped: Construction shall install cable ties and T&B adhesive mounting bases (Tefzel brand) according to the manufacturer's. recommendations. Mounting bases shall be applied at maximum 18-in intervals. Where overall wire length is less than 36 in but greater than 18 in., a mounting base shall be installed in the approximate center of the routing.
The corrective action will be completed by December 31, 1984.
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