05000219/LER-1917-005, Regarding Failure of the Emergency Diesel Generator 2 During Surveillance Testing Due to a Broken Electrical Connector
| ML18009A436 | |
| Person / Time | |
|---|---|
| Site: | Oyster Creek |
| Issue date: | 01/03/2018 |
| From: | Gillin M Exelon Generation Co |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| RA-17-083 LER 17-005-00 | |
| Download: ML18009A436 (4) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 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)(iv)(A), System Actuation 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)(v)(B), Loss of Safety Function - Remove Residual Heat 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability |
| 2191917005R00 - NRC Website | |
text
RA-17-083 January 3, 2018 U.S. Nuclear Regulatory Commission Attn: Document Control Desk or 0-881 One White Flint North 11555 Rockville Pike Rockville, MD 20852 Oyster Creek Nuclear Generating Station Renewed Facility Operating License No. DPR-16 NRG Docket No. 50-219 Oyster Creek Route 9 South P.O. Box388 Forked River, NJ 08731 10 CFR 50.73
Subject:
Licensee Event Report (LER) 2017-005-00, "Failure of the #2 Emergency Diesel Generator During Surveillance Testing due to a Broken Electrical Connector" Enclosed is LER 2017-005-00 reporting the electrical connector failure on a current differential relay for #2 Emergency Diesel Generator during the performance of surveillance testing.
This event did not affect the health and safety of the public or plant personnel. This event did result in a safety system functional failure: There are no regulatory commitments made in this LER submittal.
Should you have any questions concerning this report, please contact Gary Flesher, Regulatory Assurance Manager, at (609) 971-4232.
Respectfully, Michael F. Gillin Plant Manager Oyster Creek Nuclear Generating Station Enclosure: NRG Form 366, LER 2017-005-00 cc:
Administrator, NRG Region I NRG Senior Resident Inspector - Oyster Creek Nuclear Generating Station NRG Project Manager - Oyster Creek Nuclear Generating Station
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY 0MB: NO. 3150-0104 EXPIRES: 10/31/2018 (06-2016}
, the http://www.nrc.i:iov/readini:i-rm/doc-collections/nurei:is/staff/sr1022/r3/)
NRG may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 3. PAGE Oyster Creek Nuclear Generating Station 05000219 1 OF 3
- 4. TITLE Failure of the Emergency Diesel Generator #2 During Surveillance Testing due to a Broken Electrical Connector
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED YEAR I SEQUENTIAL I REV FACILITY NAME DOCKET NUMBER MONTH DAY YEAR NUMBER NO.
MONTH DAY YEAR NIA 05000 FACILITY NAME DOCKET NUMBER 10 09 2017 2017 - 005 00 01 03 2018 NIA 05000
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMITIED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply)
D 20.2201(bl,
D 20.2203(a)(3)(il D 50.73(a)(2)(ii)(A)
D 50.73(a)(2)(viii)(A)
N D 20.2201 (dl D 20.2203(a)(3)(ii)
D 50.73(a)(2)(ii)(B)
D 50.73(a)(2)(viii)(B)
D 20.2203(a)(1)
D 20.2203(a)(4l D 5o. 13(a)(2)(iii)
D 50.73(a)(2)(ix)(A)
D 20.2203(a)(2)(il D 50.36(c)(1)(i)(A)
D 50.73(a)(2)(iv)(A)
D 50.73(a)(2)(x)
- 10. POWER LEVEL D 20.2203(a)(2)(iil D 50.36(c)(1)(ii)(A)
D 50.73(a)(2)(v)(A)
D 13.11(a)(4l D 20.2203(a)(2)(iiil D 5o.36(c)(2)
D 50.73(a)(2)(v)(B)
D 73. 11 (a)(5)
D 20.2203(a)(2)(iv)
D 5o.46(a)(3)(iil D 50.73(a)(2)(v)(C)
D 13.77(a)(1) 100 D 20.2203(a)(2)(v)
D 50. 73(a)(2)(i)(A)
D 50.73(a)(2)(v)(D)
D 1a. n<a><2)(i)
D 20.2203(a)(2)(vi)
[:8J 50. 73(a)(2)(i)(B)
D 50.73(a)(2)(vii)
D 13.11(a)(2)(ii)
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- 1<*..'.-,,.,:
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D 50.13(a)(2)(i)(C)
D OTHER Specify in Abstract below or in
- 3. LER NUMBER SEQUENTIAL NUMBER 005 REV NO.
00 The Generator Lockout relay (86G) is an auxiliary relay that is operated upon the occurrence of abnormal conditions to maintain associated equipment out of service until it is reset. The lockout (86G) relay is sealed-in when the Differential Current Relay (87G) is initiated. The failure of the wire lug would not have prevented EDG #2 from being able to start. However, in the as found condition EDG#2 was unable to start and load to supply power to the safety buses for the required mission time of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. Because EDG #1 was operable and available to supply power to its associated loads in the event of a loss of offsite power, there was no loss of safety function.
Corrective Actions
- 1. The broken ring lug connector forthe current transformer (CT5) was replaced. EDG#2 was tested and restored to operable status on 10/10/17 at 0805 hours0.00932 days <br />0.224 hours <br />0.00133 weeks <br />3.063025e-4 months <br />.
- 2.
All ring lug connectors were inspected in the current transformer and potential transformer cabinet for EDG#2.
Four other bent and/or twisted ring lug connectors were identified and replaced on 10/10/17.
- 3.
Extent of condition inspections were performed on all ring lug connectors in the current transformer and potential transformer cabinet for EDG#1.
- 4.
Two bent and/or twisted ring lug connectors were replaced on EDG#1 on 12/28/17.
- 5.
Revise electrical ring lug installation and EDG inspection procedures to include inspection for bent and/or twisted lugs.
Previous Occurrences
There have been no similar, previous events resulting from a failure of a wire lug on an EDG at Oyster Creek.
Component Data Component Emergency Diesel Generator IEEE 805 System ID EK IEEE 803A Component DG Page _3_ of _3_