ML20198C207

Notice of Deviation from Insp on 910401-0510.Deviation Noted:Breakers in 250-volt Dc Sys Sized So Fault Current Condition Could Exceed Max Current Interrupting Capability

ML20198C207
Person / Time
Site:	Quad Cities
Issue date:	06/24/1991
From:	Miller H NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION III)
To:
Shared Package
ML20198C177	List: IR 05000254/1991011 ML20198C172 ML20198C194 ML20198C207
References
50-254-91-11, 50-265-91-07, 50-265-91-7, NUDOCS 9106280180
Download: ML20198C207 (1)

Text

,

5 Notice of Deviation Commonwealth Edison Company Do c. '

,, 50-265 Quad Cities Power Station License, s sPR-29; DPR-30 .

Units 1 and 2 During an NRC inspection conducted on April I through May 10, 1991, a deviation of your Final Safety Analysis Report was identified. In Accordance with the " General Statement of Policy and Procedure for NRC Enfarcement

- Action," 10 CFR Part 2, Appendix C (1991), the deviation is listed below:

FSAR Section 8.2.2 states, in part, that all protective circuit breakers are sized according to standard electrical industry practice where maximum current "

interrupting capabilities of circuit breakers exceed the available line-to-line or three-(3) phase short circuit current taking into account F.e impedance of the generator, transformer and other elettrical system components.

Contrary to the above, as of May 10, 1991, breakers in the 250Vdc system were sized such that a fault current condition could exceed their maximum current interrupting capability by up to 80%; and breakers in the 4kV system could experience a fault current condition that would exceed their maximum current interrupting capability by up to 9%.

Please provide to the U.S. Nuclear Regulatory Commission, ATTN: Document Control Desk, Washington, D.C. 20555, with a copy to the Regional Administrator, Region 111, and a copy to the NRC Resident Inspector at the facility that is the subject of this Notice, in writing within 30 days of the date.of this Notice, the reason for the deviation, the corrective steps which have been taken and the results achieved, the corrective steps which will be taken to avoid further deviations, and the date when your corrective action will be completed. Where good cause is siime.'n, considei ation will be given to extending the response time.

/ '141 Dated atr j,len Ellyn, Illinois /.

. this _didyday of June 1991 H. 7. Miller, Director Division of Reactor Safety 9106200160 91Ch$24 i FDR ADOCK 03000254 '

O PC,7

_-