ML20099K365

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Final Deficiency Rept,Item 168 & Part 21 Rept Re Siemens- Allis Switchgear Breakers Remaining Energized,Preventing Breaker Closing.Initially Reported on 840326 & 0420.Green Indicator Lights Rewired to Negative Side of Trip Coil
ML20099K365
Person / Time
Site: Harris 
Issue date: 11/08/1984
From: Parsons R
CAROLINA POWER & LIGHT CO.
To: James O'Reilly
NRC OFFICE OF INSPECTION & ENFORCEMENT (IE REGION II)
References
CON-NRC-289, REF-PT21-84 168, NUDOCS 8411290401
Download: ML20099K365 (5)


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Carolina Power & Light Company P.O. Box 101, New Hill, NC 27562 November 8,1984 Mr. James P. O'Reilly NRC-289 United States Nuclear Regulatory Commission Region II 101 Marietta Street, Northwest (Suite 2900)

Atlanta, Georgia 30323 CAROLINA POWER & LIGHT COMPANY SHEARON HARRIS NUCLEAR POWER PLANT 1986 - 900,000 KW - UNIT 1 6.9KV SWITCHGEAR CIRCUIT BREAKERS - GENERIC ITEM 168

Dear Mr. O'Reilly:

Attached is the final rep) ort on the subject item, which was deemed reportable per the provisions of 10CFR50.55(e and 10CFR, Part 21 on April 20, 1984. With this report, Carolina Power & Light Company considers this matter closed.

If you have any questions regarding this matter, please do not hesitate to contact me.

Yours very truly, 7?f &

R. M. Parsons Project General Manager Shearon Harris Nuclear Power Plant RMP/das Attachment cc:

Messrs. G. Maxwell /R. Prevatte (NRC-SHNPP)

Mr. R. C. DeYoung (NRC) 1 i

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OFFICIAL COPY 1%hl841108oSo00 g p

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NRC-289 Mr. James P. O'Reilly bbc: Mr. H. R. Banks Mr. C. S. Bohanan Mr. H. W. Bowles Mr. C. Carmichael (2)

Mr. G. S. Cashell f 'r. N. 3. Chiangi Mr. A. B. Cutter Dr. T. S. Elleman Ms. S. F. Flynn Mr. G. L. Forehand Mr. 3. F. Garibaldi (Ebasco)

Mr. 3. L. Harness Mr. P. C. Hopkins Dr. 3. D. E. Jeffries Mr. I. A. Johnson Mr. L. I. Loflin Mr. R. E. Lumsden Mr. R. L. Mayton, Jr.

Mr. M. A. McDuffie Mr. S. McManus Mr. C. H. Moseley, Jr.

Mr. D. L. Nordstrom (LIS)

Mr. R. M. Parsons Mr. Sheldon D. Smith Mr. A. C. Tollison Mr. R. A. Watson Mr. M. Shannon (Westinghouse)

Mr. 3. L. Willis Mr. T. A. Baxter (Shaw, Pittman, Potts & Trowbridge)

Mr. M. F. Thompson, Jr.

Mr. S. Hinnant Mr. 3. F. Nevill File: HI/A-2D File: H-X-0544 Records Center-INPO

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t CAROLINA POWER & LIGHT COMPANY SHEARON HARRIS NUCLEAR POWER PLANT UNIT NO. 1 FINAL REPORT CIRCUIT BREAKER CONTROL WIRING CONFIGURATION NCR-84-799 ITEM No. 168 NOVEMBER 9, 1704 REPORTABLE UNDER 10CFR50.55(e) AND 10CFR21 I

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Shearon Harris Nuclear Power Plant / Unit No. I i

SUBJECT:

10CFR50.55(e) and 10CFR Part 21 reportable Wiring for the control circuitry for deficiency.

6.9kV switchgear was such that the trip coil could remain energized following a trip of the breaker.

This would have resulted in the inability to reclose the breaker.

Wiring for 6.9kV switchgear breakers ITEM:

Siemens-Allis, Inc., Sanford, North Carolina.

SUPPLIED BY:

NATURE OF During 1980, the switchgear division of DEFICIENCY:

Siemens-Allis, Inc., Sanford, North Carolina, shipped 6.9kV switchgear breakers to the CP&L site on Purchase Orders NY-435112 and NY-435113.

As part of the start-up testing of these breakers, they are j

routinely cycled before a breaker is put in service.

During this testing, it has been found that in some cases the trip coil would remain energized preventing the breaker from being reclosed. The only'way to i

restore operability to the breaker is to disconnect the control voltage source and then reenergize.

Investigation of this problem has determined that the problem results from the control wiring of the trip

coil, it was CP&L-Ebasco's intent to monitor the trip coil both in the breaker closed and breaker open position. This is not a Siemens-Allis standard wiring technique, so they were unaware that there is suf ficient current through the green (open) indicator light circuit to hold the trip coil in an energized state once the breaker is tripped.

DATE PROBLEM OCCURRED:

Refer to above section.

DATE PROBLEM REPORTED:

On March 26, 1984, CP&L (N. J. Chiangi) notified the NRC (Mr. A. Hardin) that this item was potentially reportable under 10CFR50.55(e) and 10CFR, Part 21.

On April 20, 1984, CP&L (K. V. Hate') notified the NRC (Mr. A. Hardin) that this item was reportable under 10CFR50.55(e) and 10CFR, Part 21.

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.,,o SCOPE OF PROBLEM:

This problem affects safety and nonsafety breakers as supplied by Siemens-Allis under Ebasco Purchase Orders NY-435112 and NY-435113.

For the nonsafety breakers, this is not a safety concern, but it is an operational limitation. This will affect 25 safety breakers and 57 nonsafety breakers.

SAFETY IMPLICATION:

Safety-related loads during a loss of coolant accident and loss of off-site power will be tripped from the plant electrical system and reloaded onto the emergency diesels. As previously wired, some of the breakers could have failed to reclose following the transfer to the emergency diesel generators.

REASON DEFICIENCY IS REPORTABLE:

This is reportable as a design error since, as previously designed, the switchgear could prove to be inoperative during a plant emergency condition, such as loss of coolant accident or any other circumstance requiring the initiation of loads onto the plant emergency power system as supplied by the emergency diesel generators.

CORRECTIVE ACTION:

1.

Rewiring of the green indicator lights to the negative side of the trip coil will eliminate the current flow through the indicator lights from holding the trip coil in an energized state following the tripping of a breaker.

2.

Since as previously wired there was not sufficient length of wire to move the wire from the green indicator light to the negative terminal of the trip coil Siemens-Allis has supplied a new wire to go from the 52b contact to the negative terminal of the trip coil. The previous wiring from the 52b contact to the high side of the trip coil has been removed and discarded.

The removal of the old wire and installation of the new wire has been completed.

The equipment has been cycled to verify proper operation. Rewiring and testing of the referenced breakers completes the corrective action required for this deficiency.

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