ML20154E656

Interim Deficiency Rept Re Use of Mechanical Cable Connectors on Westinghouse Type Ds Fused Disconnect Switches.Initially Reported on 880415.Determination of Extent That Both Wires Terminated W/Connectors Underway

ML20154E656
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 8805200278
Download: ML20154E656 (2)

Text

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l PHILADELPHIA ELECTRIC COMPANY 2301 MARKET STREET P.O. BOX 8699 ,

PHILADELPHI A. PA.19101 (215) s414so S. J. KOWALSKI vsctPmaslDENT

.m..............

May 13, 1988 ,

United States Nuclear Regulatory Cctrmission Attn: Doctment Control Desk Washington, DC 20555

SUBJECT:

Interim Report for Limerick Generating Station, Unit 2 Westinghouse Type DS Fused Disconnect Switch Mechanical Cable Connectors Limerick Generating Station, Unit 2 NRC Construction Pennit No. CPPR-107

REFERENCE:

Telecon of PECo to NRC dated April 15, 1988 FILE: QUAL 2-10-2 (SDR #232-2)

Dear Sir:

In compilance with 10CFR Part 50.55(e), we are hereby submitting an interim report concerning the use of mechanical cable connectors on Westinghouse Type DS fused disconnect switches at Limerick Generating Station Unit 2. The Philadelphia Electric Ccrnpany (PECo) discussed this condition by telephone with the NRC Regional Office of Inspection and Enforcement on April 15, 1988, after it was determined that this may be a reportable condition.

On March 30, 1988 the Nuclear Engineering Division of Philadelphia Electric Ccrnpany (PECo) was advised of a potential problem which may exist in Westinghouse Type DS fused disconnect switches at Limerick Generating Station Unit 2. >

During the connection of Unit 2 fleid cables to Westinghouse Type DS fused disconnect switches, it was noted that mechanical connectors integral to the fuse mounting asserrbly would not adequately secure  !

scme #8 AWG wires although the connectors themselves were marked l 114-1/0. This condition has the potential to result in excessive beating of the cable connector Interface, or a cable could possibly

- beccme disconnected, thereby disabling a circuit. The connector is designed with a set screw engaging threads within the fuso clip holder.  !

Scme set screws, when Inserted into the block to the maximun depth (detennined by the block's threading) do not contact the opposing face of the block.

8805200279 880513 A

! PDR ADOCK 05000352 S nnn

I A sanple of connectors removed frcm Unit 2 indicated a large variation in the gap that results after setting the screw to its nuxinun depth. In certain instances, connectors with the widest gaps could not be used to adequately terTninate wires up to size v6 AhG.

At Limerick Generating Station, 910 AWG wires (the smallest gauge used for power conductors) are terminated with a ccanpression lug and do not use rnechanical connectors.

We are currently determining the extent that both #8 AWG and h6 AhG wires are terminated with these connectors and the corrective action required A detailed report will be flied after our evaluation is ccmpleted and corrective action determined. It is expected that the evaluation and detailed report will be ccmpleted by June 15, 1988.

Sincerely,

/j, S'/d-l-3iHw /s, j.

JJMC/ghr/05138801 Copy to: USNRC Site Resident inspector United States Nuclear Regulatory Ccomission Region !

631 Park Avenue King of Prussia, PA 19406 l