ML19329E405
| ML19329E405 | |
| Person / Time | |
|---|---|
| Site: | Fort Calhoun, Midland  |
| Issue date: | 10/25/1974 |
| From: | James Keppler NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III) |
| To: | Howell S CONSUMERS ENERGY CO. (FORMERLY CONSUMERS POWER CO.) |
| References | |
| NUDOCS 8006120729 | |
| Download: ML19329E405 (1) | |
Text
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UNITED STATES l.T 1
ATOMIC ENERGY COMMISSION g
Q DIRECTORATE OF REGULATORY OPERATIONS
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- 4'f1 S' 799 ROOSEVELT ROAD 7ggg,gogg GLEN ELLYN, ILLINOIS 60137 (312) 858 2660 October 25, 1974 Consumers Power Company Docket No. 50-329 ATTMt Mr. Stephen H. Howell Docket No. 50-330.
Vise President 1945 West Parnall Road Jackson, Michigan 49201 Gene 1====:
The analosed R0 Bulletin requests actions by you with regard to your reestor facilities with operating lie==== or construction permit.
Should you have questicas regarding this Bulletin or actions requested of you, please contact this offiaa.
Sincerely yours, James G. Keppler Regional Director Enslosure:
RD Bulletin 74-13 THIS DOCUMENT CONTAINS bec: DR Central Piles RO Files P0OR QUALITY PAGES PDR Local PDR Ronald Callen Dr. Wayne North Myron M. Cherry 8006 120 %
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m October 25, 1974 RO Bulletin No. 74-13 IMPORPER FACTORY WIRING ON GENERAL ELECTRIC MOTOR CONTROL CENTERS AT FORT CALHOUN We recently received information from Omaha Public Power District describing a deficiency in the factory wiring on GE type 7700 MCC breaker-starters. The improper wiring was discovered in both safety related and non-safety related breaker-starters at the Fort Calhoun nuclear power plant.
Description of Circumstances OPPD reported the insulation on the power carrying wires in the combination breaker-starter for the non-safety related demineralized water transfer pump burned due to over-current and improper factory wiring practices. The improper factory wiring was discovered while OPPD pqrsonnel were rewiring the breaker-starter (GE type 7700 MCC, THEF-100A, 3 phase, 480 V, FVNR Size 3).
The factory installed wire was GE Vulkene "600" Cable Type XHHW SI-58053 B 4AWG 600 V (UL). The wire is made of stranded copper conductors covered by cellophane tape which in turn is covered by an outer cable jacket.
In the affected breaker-starter, the cellophane tape had not been removed after the cable jacket was stripped off; therefo're, the lug was crimped directly over the cellophane resulting in a limited contact surfac between the conductor and the lug. When the motor overloaded, due to worn bearings, excessive heating occurred at the lug-cellophane-conductor interface causing the cable jacket to burn and the molded case circuit breaker to be deformed.
Inspection of all GE MCC switchgear revealed 13 out of 20 GE MCC's wired with GE Vulkene "600", Cable Type XHHW, SI-58053 B 4 AWG were wired improperly. A similar problem existed in 3 out of 11 breakers where GE Vulkene "600", Cable Type XHHW, SI-58053 B 2 AWG wire was used. The problem was found to be characteristic of the cable type and wire size rather than the breaker-starter size.
OPPD reported that the problem has been discussed with GE and that GE plans to replace the wire in the affected breaker-starters at Fort Calhoun.
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,.S RO Bulletin No. 74-13 October 25,.1974
. Action Requested of Licensees It is requested that you review the use of GE Vulkene "600" cable in safety related breaker-starters of your facilities, and provide the i
following information to this office in writing within 60 days:
Where GE Vulkene "600" cables of the breaker-starters type described above have been used in safety related breaker-starters of your facilities, describe the action you have taken or plan to take to insure against improper termination of these cables similar to that described above.
Your written reply to this Bulletin should include a description of the number and location of any cables found to be improperly terminated, together with the date corrective measures were, or will be, completed.
If GE Vulkene "600" cables of the type breaker-starters described above have not been used in safety related breaker-starters of your facilities, your written response should indicate this to be the case.
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