ML20083N973
| ML20083N973 | |
| Person / Time | |
|---|---|
| Site: | Harris  |
| Issue date: | 01/28/1983 |
| From: | Parsons R CAROLINA POWER & LIGHT CO. |
| To: | James O'Reilly NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II) |
| References | |
| CON-NRC-38, REF-PT21-83 10CFR-050.55E, 10CFR-50.55E, NUDOCS 8302030304 | |
| Download: ML20083N973 (4) | |
Text
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e Cp&L Carolina Power & Light Company 3 FTp j g.O. Box 101,NewHill,N.C. 27562
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January 28, 1983 Mr. James P. O'Reilly NRC-38 United States Nuclear Regulatory Commission Region II 101 Marietta Street, Northwest (Suite 3100)
Atlanta, Georgia 30303 CAROLINA POWER & LIGHT COMPANY SHEARON HARRIS NUCLEAR POWER PLANT 1986-1990 - 900,000 KW - UNITS 1 & 2 480V SWITCHGEAR DESIGN DEFICIENCY OF THE SECONDARY DISCONNECTS, NY-435171, ITEM 106
Dear Mr. O'Reilly:
Attached is our second interim report on the subject item which was deemed reportable per the provisions of 10CFR50.55(e) and 10CFR, Part 21, on November 2, 1982. CP&L is pursuing this matter, and it is currently projected that corrective action and submission of the final report will be accomplished by April 29, 1983.
Thank you for your consideration in this matter.
Very truly yours, Y
R. M. Parsons Project General Manager Shearon Harris Nuclear Power Plant RMP/sh Attachment cc:
Mr. G. Maxwell (NRC-SHNPP)
Mr. V. Stello UFFICIAL Ct5qi2 A
8302030304 030128 PDR ADOCK 05000400 g
PDR 1
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4 CAROLINA POWER & LIGHT COMPANY SHEARON HARRIS NUCLEAR POWER PLANT UNIT NO. 1 d
I 480V SWITCHGEAR DESIGN DEFICIENCY OF THE SECONDARY DISCONNECTS ITEM 106 INTERIM REPORT JANUARY 27, 1983 REPORTABLE UNDER 10CFR50.55(e)
.AND 10CFR21 i
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SUBJECT:
Shearon Harris Nuclear Power Plant Unit 1 10CFR50.55(e) and 10CFR21 r? portable deficiency on the secondary disconnects on the 480V switchgear: Item 106.
ITEM:
Secondary disconnects located on the circuit breaker cradles on the 480V switchgear which mate with the finger contacts on the circuit breaker.
SUPPLIED BY:
Brown-Boveri Company, Chalfont, Pa.
NATURE OF DEFICIENCY:
From April 1982 to November 1982, Brown-Boveri Company shipped Class lE 480V switchgear to the Shearon Harris site under Purchase Order NY-435171.
In October 1982, it was discovered that the circuit breaker cradles were assembled using an older design of the secondary disconnects.
(The secondary disconnects are the points where control power is supplied to the circuit breaker.) This older design was manufactured with rectangular tabs that hold contact strips in place and also a small cut-out in the contact strip located directly behind the rectangular tab (Part No. 712209-TI).
Brown-Boveri has advised us that there is a chance that the finger contacts can get caught behind the rectangular tabs in the contact strip cut-out and can break off when the circuit breakers are racked out of the cradles.
Therefore, control power to the circuit breakers could be lost.
DATE PROBLEM REPORTED:
November 2, 1982 - CP6L (C. L. McKenzie) notified the NRC (C. Hehl) that this item is reportable under 10CFR50.55(e) and 10CFR21.
SCOPE OF PROBLEM:
The deficiency involves four Unit 1 Class lE 480V switchgear (52 cubicles).
SAFETY IMPLICATIONS: The Class lE 480V switchgear supplies electrical power to nuclear safety-related equipment. Loss of control power to certain circuits in the 480V switchgear circuit breaker could result in improper functioning of the circuit breaker and thus affect power availability to nuclear safety-related equipment.
CORRECTIVE ACTION:
The secondary disconnects presently installed in the breaker cradle will be replaced with a newly designed secondary disconnect that will not cause the finger contacts on the circuit breaker to break.
f FINAL REPORT:
Brown-Boveri Company is presently replacing the disconnects.
Approximately eighty (80) percent of the non-safety switch-gear has been completed. Prior to replacing any of the disconnects on the safety switchgear, CP&L must review the vendor'a procedures which are presently being written. We project that all work on the switchgear will be completed by mid to late April. A final report will be submitted by April 29, 1983.
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