ML20006D691

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Provides Alternative Design Solution to Dcrdr Implementation at Facilities.Simpler Design Devised,Using Eyelet Screw Inserted in Switch Nameplate Which Is Identical to Providing Caution Cards in Close Proximity to Switch Handle
ML20006D691
Person / Time
Site: Byron, Braidwood, 05000000
Issue date: 02/02/1990
From: Schuster T
COMMONWEALTH EDISON CO.
To: Murley T
Office of Nuclear Reactor Regulation
References
0640T, 640T, NUDOCS 9002140256
Download: ML20006D691 (1)


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/ } Commonwealth Edison One Fitt National Plaza, Chicago, linois f

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Kdikess Reply to: Post Office' Box 767 ~

1\ . Chicago, Ilknois 00690 0767 -

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, ' February 2, 1990

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.Dr.vThomas E. Murley, Director

-Offlee of Nuclear Reactor Regulation

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, .U.D. Nuclear Regulatory Commission  ;

, q; QWu hington, DC- 20555

Subject:

Byron Station Units 1 and 2 Braidwood Station Units 1 and'2 DCRDR Implementation .. .

W!a_Dp.chr1 Rob 50-454/A55 and 50-456/457

Reference:

7(a) hne 30, 1989 letter from R. A. Chrzanowski to L E. Marley regarding DCRDR Implementation at. Byron /Braidwood Stations e

Dear Dr. Murley:

5 Reference (a) provided an implementation schedule and some specific design details for four HEDS. This letter provides an alternative design solu-tion to that proposed for HED #301, which will be utilized at Byron Station.

HED #301 doctunented a concern with the possible dislodging of Out of Service

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(00S) and Caution cards hung around Westinghouse type OT2 " thumb control switches" when mu11tiple cards are on one switch. ,

The original design solution, as implemented at Braidwood Station during their last refueling on Unit 1, was installation of a-ring behind the "

switch face to which the strings of the 00S and Caution Cards may be attached.

Since the Braidwood Unit 1 installation, a simpler design using an eyelet screw inserted in the switch nameplate has been implemented on Byron Unit 1. -Although the form has. changed, the design is identical in function providing a location for attachment of 00S and Caution Cards in close proximity to the switch handle ,

with no fear of loss or misplacement. Both the CECO Nuclear Engineering and. i Human Engineering departments have reviewed and approved of this alternative approach. The schedule proposed-in the referenced letter remains unchanged for

! both Byron and Braidwood. Although Braidwood has installed the original design on the Unit 1 Main Control Board, it will consider installation of the new design on Unit 2 and possible retrofit of Unit 1. However, the currently installed design on Braidwood Unit 1 satisfies the concerns identified in HED ,

  1. 301.

Please direct any further questions on this subject to this office.

Very truly yours, 90021402 FDR ADO {f[h4PDC T. K. Schuster

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l P Nuclear Licensing Administrator cc: Byron Resident Inspector Braidwood Resident Inspector l

P. C. Shemanski - NRR /

S. Sands -NRR p 00 Region III Office

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