ML20154E638

Interim Deficiency Rept Re Aluminum Vertical Bus Failures in Cutler Hammer Motor Control Ctr.Initially Reported During 880415 Telcon W/Nrc Regional Ofc.Evaluating Condition W/ Mfg.Next Rept Will Be Submitted by 880715

ML20154E638
Person / Time
Site:	Limerick
Issue date:	05/13/1988
From:	Kowalski S PECO ENERGY CO., (FORMERLY PHILADELPHIA ELECTRIC
To:	NRC OFFICE OF ADMINISTRATION & RESOURCES MANAGEMENT (ARM)
References
NUDOCS 8805200274
Download: ML20154E638 (2)

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r PHILADELPHI A ELECTRIC COM PANY 2301 M ARKET STREET P.O. DOX 8609 PHicADELPHI A. PA.19101 tat s) e41 aso S. J. KOW A LS Kl vict PassioENT

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May 13, 1988 United States Nuclear Regulatory Ccomission Attn:

Docurent Control Desk Washington, DC 20555

SUBJECT:

Interim Report for Limerick Generating Station, Unit 2 Aluminun Vertical Bus Fallures in Cutler Hartmr MCCs Limerick Generating Station, Unit 2 NRC Construction Permit No. CPPR-107

REFERENCE:

Telecon of PECo to NRC dated 4/15/88 FILE:

QUAL 2-10-2 (SDR 4230-2) e Dear Sir In ccG liance with 10CFR Part 50.55Ce), we are hereby submitting an interim report concerning the use of Alunintm Vertical Bus in Cutler-Hmirar MCCs at Limerick Generating Station Unit 2. The Philadelphia Electric Ccnpany (PECo) discussed this condition by telephone with the NRC Regional Office of Inspection and Enforcement on April 15, 1988, after it was deterTained that this ruy be a reportable condition.

On February 23, 1988 the Nuclear Engineering Division of Philadelphia Electric Ccepany (PECo) was advised of a potential problem which nuy exist in the cotor co.itrol centers at Lirnerick Generating Station Unit 2.

A failed altmlntm vertical bus was discovered in the waste water treatraent plant notor control center at our Eddystcce Generating Station. Af ter exmilnation of the bus section by FECo and the manufacturer (Cutler-Harmer) the problem is believed to have been caused by heat build-up which, over a period of tine, deteriorates the connection point between the copper stab and the aluninun vertical bus.

The nunufacturer has indicated that the potential for failure coly exists for altminun vertical bus sections feeding NEPA size 4 notor starters. Lincrick Generating Station Unit 2 al,o utilizes motor control centers with alunintm vertical bus sections and size 4 starters, nunufactured by Cutler-Hanter, in safety -related applications.

Therefore, due to the potential for almilar failures to occur at Llrrerick Generating Statico Unlt 2 we have concluded that this is a reportable ccridition.

We are currently evaluating this ccoditicn and are in contact with the runufacturer to determine the extent of the ecodition, the root cause and the corrective action required.

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A detalled report will be filed after our evaluation is ccmpleted and corrective action determined.

It is expected that the evaluation and detailed report will be ccmpleted by July 15, 1988.

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