05000348/LER-2007-001, From Joseph M. Farley Nuclear Plant - Unit 1, Re Technical Specification 3.8.1 Violation Due to Failure of Breaker/Mechanism-Operated Cell (MOC) Switch
| ML071760334 | |
| Person / Time | |
|---|---|
| Site: | Farley  |
| Issue date: | 06/22/2007 |
| From: | Jerrica Johnson Southern Nuclear Operating Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| NL-07-1231 LER-07-001-00 | |
| Download: ML071760334 (6) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(v)(B), Loss of Safety Function - Remove Residual Heat 10 CFR 50.73(a)(2)(i) 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(viii)(A) 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(viii)(B) 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(x) 10 CFR 50.73(a)(2)(v)(A), Loss of Safety Function - Shutdown the Reactor 10 CFR 50.73(a)(2)(i)(A), Completion of TS Shutdown 10 CFR 50.73(a)(2)(v), Loss of Safety Function |
| 3482007001R00 - NRC Website | |
text
J. R. Johnson Southern Nuclear V ~ r e F'res~ileril - Farley Operating Company, Inc.
Pod Offtce Drawer 470 Asl~fntrl, Alal~~rnd 3631 2-0470 June 22,2007 Eneru t o Surtw Your World' Docket Nos.: 50-348 50-364 U. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, D. C. 20555-0001 Joseph M. Farley Nuclear Plant - Units I and 2 Licensee Event Report 2007-001 -00 Technical Specilication 3.8.1 viola ti or^ Due to Failure of Breaker / Mechanism-O~erated Cell Switch Ladies and Gentlemen:
Joseph M. Farley Nuclear Plant - Licensee Event Report (LER) No. 2007-001 -00 is being submitted in accordance with 10 CFR 50.73(a)(2)(i)(B) and 10 CFR 50.73(a)(2)(v)(B).
This letter contains no NRC commitments. If you have any questions, please advise.
Vice President - Farley Joseph M. Farley Nuclear Plant 7388 North State Highway 95 Columbia AL 3f3319 JRJICHM Enclosure: Licensee Event Report 2007-001 Unit 1
U. S. Nuclear regulatory Commission NL-07-1231 Page 2 cc:
Southern Nuclear Operatinq Company Mr. J. T. Gasser, Executive Vice President Mr. J. R. Johnson, Vice President - Farley Mr. D. H. Jones, Vice President - Engineerirlg RTYPE: CFA04.054; LC # 14596 U. S. Nuclear Reaulatorv Commission Dr. W. D. Travers, Regional Administrator Ms. K. R. Cotton, NRR Project Manager - Farley Mr. E. L. Crowe, Senior Resident Inspector - Farley
I LICENSEE EVENT REPORT (LER)
I (See reverse for reauired number of digitslcharacters {or each block)
- 1. FACILITY NAME Estimaled burden per response to comply with this mandatory oollecbo~
request: 50 hours5.787037e-4 days <br />0.0139 hours <br />8.267196e-5 weeks <br />1.9025e-5 months <br />. Repotled lessons learned are incorporated into thl licensing p-and fed back to industry. Send comments r ardi estimate to the Records and FOIAIPrivacy Service Branch?-5 22pE.t Nudpr R ulatory Commission. Washington. DC 20555-0001, or by interne em11 to I~!lled@nrc. ov and to the Desk Officer. Office of lnformatlol and Regulatory Aflairs. N E ~ B ~ O Z O ~,
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a currently valid OMB control numktr, the NRC ma and a person IS not requ~red to resmd to, th~
- 12. DOCKET NUMBER
- 13. PAGE Joseph M. Farley Nuclear Plant - Unit 1 I
05000 348 I
1 OF 4
- 14. TITLE Technical Specification 3.8.1 Violation Due to Failure of Breaker I Mechanism-Operated Cell (MOC) Switch I
1 04 I
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ABSTRACT (Limit to 1400 spaces. i e., approximately 15 single-spaced typewritten lines)
I While performing Emergency Diesel Generator (EDG) IC Operability Test on April 26,2007, FNP determined that the mechanism-operated cell (MOC) switch of the 1C EDG output breaker 1-DH07 was not being fully activated when the breaker was closed. This resulted in the EDG being declared inoperable. An inspection determined that the MOC switch rotation was not sufficient to fully engage the normally open contacts. The event was the result of a fit-up discrepancy during replacement of the existing Allis Chalmers breakers with new Cutler Hammer breakers within the Allis Chalmers switchgear. The fit up discrepancy went unrecognized because of inadequate procedural guidance on how the replacement breakers were to be setup during initial installation and testing. Because the breaker had been in this condition since November 1, 2006, this event was determined to be reportable per IOCFR50.73(a)(2)(i)(B), "any operation or condition which was prohibited by the plant's Technical Specifications." Due to the fact that the opposite train I B EDG was unavailable during maintenance activities on five occasions during this time period, the event is also reportable per 1 OCFR50.73(a)(2)(v)(B), "any event or condition that could have prevented the fulfillment of the safety function of structures or systems which are needed to remove residual heat." At the time ofdiscovery, the 1 B EDG was fully operable and available.
1
- 5. EVENT DATE I
I 1
I l o. POWER LEVEL I
I 100 I
After the event, plant procedures were updated to provide detailed instructions on setup of the MOC switches.
All installed Cutler Hammer breakers with MOC switches that provide essential functions have been adjusted per MONTH 26 20.2201(b) 20.2203(a)(3)(i) 50.73(a)(2)(i)(C) 50.73(a)(2)(vii) 20.2201(d) 20.2203(a)(3)(ii) 50,73(a)(2)(ii)(A) 50.73(a)(2)(viii)(A) 20.2203(a)(l) 20.2203(a)(4) 50.73(a)(2)(ii)(B) 50.73(a)(2)(viii)(B) 20.2203(a)(2)(i) 50.36(c)(l)(i)(A) 50,73(a)(2)(iii) 50.73(a)(2)(ix)(A) 20.2203(a)(2)(ii) 50.36(c)(l)(ii)(A) 50,73(a)(2)(iv)(A) 50.73(a)(2)(x) 20.2203(a)(2)(iii) 50.36(~)(2) 50.73(a)(2)(v)(A) 73.71(a)(4) 20.2203(a)(2)(iv) 50.46(a)(3)(ii)
[XI 50.73(a)(2)(v)(B) 73.71(a)(5) 20.2203(a)(2)(v) 50.73(a)(2)(i)(A) 50.73(a)(2)(v)(C)
OTHER 20.2203(a)(2)(vi)
El 50.73(a)(2)(i)(B)
I3 50.73(a)(2)(v)(D) speafy in Abstrad below or in =
(If more space is required, use additional copies of (If more space is required, use additional copies of NRG Fom 366A) (17)
I Safety Assessment I
This event had no adverse effect on the safety and health of the public.
The Farley onsite standby power source is provided from four EDGs (I -2A. I B, 28, and I C). The continuous service rating of lC EDG is 2,850 kW and 4,075 kW for EDGs 1-2A, 1 B, and 2B. EDG 1-2A and l-C are A-Train and EDGs 1 B and 2B are B-Train. Farley also has a fifth diesel generator (2C) that serves as a station blackout diesel which can be manually aligned to supply B-Train power to either unit and power LOSP loads.
The redundant train I B EDG was unavailable for operation due to maintenance activities on five occasions during the time period when the I C EDG was inoperable, resulting in a potential loss of safety function.
However, the only scenario which would have been affected by this failure is a dual unit loss of offsite power with a concurrent safety injection on Unit 2. If that event occurred with the IC DG MOC switch inoperable, operator action would have been required to energize the IF 4 160V bus and start the required safety related loads after the I C EDG automatically connected to the I H bus. This does not represent an increase in risk as calculated by the Farley Unit I Probability Risk Assessment (PRA) model. This is due to the fact that the PRA model conservatively assumes that the IC EDG will be started and loaded by the operator rather than crediting automatic start. This is a simplification of the model due to the complexities of modeling all possible combinations of swing diesel alignment.
I
Corrective Action
I The MOC operator on breaker I-DH07 was adjusted to allow adequate travel of the MOC switch contacts.
This was completed on April 26, 2007.
Plant procedures were updated to provide instructions to have the Normally Open contacts of the MOC switch rotated to the correct angle. This was completed on May 5,2007.
After receiving the additional guidance from AREVA, breaker I -DH07 was restored to match the factory setting for MOC switch operator height and the contact angle. This was completed on June 1 1,2007.
Cutler-Hammer breakers which have been installed with MOC switches that provide essential functions have been adjusted to meet the factory setting for MOC switch opetator height and contact angle. This was completed on June 1 1,2007.
NUL POKM 3W (7-2001)
NRC FORM E 0 A (7-2001)
(If more space is required, use additional copies of NRC Form 366A) (17)
Additional Information
PAGE (3) 4 OF 4
The following LER's have been submitted in the past two years on Technical Specification violations:
FACILITY NAME (1)
Joseph M. Farley Nuclear Plant Unit - 1 LER 2005-001-00 Unit I Technical Specification 3.3.2.C Violation due to Solid State Protection System Card Failure Troubleshooting DOCKET (2)
NUMBER 05000 348 LER NUMBER (6)
LER 2005-002-00 Unit 1 Technical Specification 3.8.1 Violation due to IF Bus Synchroscope Failure LER 2005-001-00 Unit 2 Gas Binding of the Unit 2 A Train HHSl Pump REVISION NUMBER YEAR LER 2006-002-00 Unit 1 Main Steam [solation Valve Failure to Close SEQUENTIAL NUMBER JRC FORM 366 (7-2001)
IRC FORM 366A (7-ZWI)