05000423/LER-2002-002, Breaker Mechanism Failure Results in Inoperable Emergency Diesel Generator
| ML021680440 | |
| Person / Time | |
|---|---|
| Site: | Millstone  |
| Issue date: | 04/11/2002 |
| From: | Schwarz C Dominion Nuclear Connecticut |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| B18639 LER 02-002-00 | |
| Download: ML021680440 (5) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(iii) 10 CFR 50.73(a)(2)(x) 10 CFR 50.73(a)(2)(iv)(A), System Actuation 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)(i)(A), Completion of TS Shutdown |
| 4232002002R00 - NRC Website | |
text
" Dominions Dominion Nuclear Connecticut, Inc.
Millstone Power Station Rope Ferry Road Waterford, CT 06385 APR I 1 2002 Docket No. 50-423 B18639 RE: 10 CFR 50.73(a)(2)(i)(B)
U.S. Nuclear Regulatory Commission Attention: Document Control Desk Washington, DC 20555 Millstone 'Nuclear Power Station, Unit No. 3 Licensee Event Report 2002-002-00 Breaker Mechanism Failure Results in Inoperable Emergency Diesel Generator This letter forwards Licensee Event Report (LER) 2002-002-00, documenting an event at Millstone Nuclear Power Station, Unit No. 3, on December 26, 2001, that was determined reportable on March 14, 2002. This LER is being submitted to document a condition determined to be reportable in accordance with 10 CFR 50.73(a)(2)(i)(B).
There are no regulatory commitments contained within this letter.
Should you have any questions regarding this submittal, please contact Mr. David W. Dodson at (860) 447-1791, extension 2346.
Very truly yours, DOMINION NUCLEAR CONNECTICUT, INC.
C.
St ion OeDraio Nuclear Station Operations and Maintenance Attachment (1):
LER 2002-002-00 cc:
H. J. Miller, Region I Administrator V. Nerses, NRC Senior Project Manager, Millstone Unit No. 3 NRC Senior Resident Inspector, Millstone Unit No. 3 Vg 6 p IP o-xoyrb
Docket No. 50-423 B18639 Millstone Nuclear Power Station, Unit No. 3 LER 2002-002-00
NRC FORM 366 U.S. NUCLEAR REGULATORY APPROVED BY OMB NO. 3150-0104 EXPIRES 7-31-2004
, the NRC may not conduct or sponsor, (See reverse for required number of digits/characters for each block) and a person is not required to respond to, the information collection.
FACILITY NAME (1)
DOCKET NUMBER (2)
PAGE (3)
Millstone Nuclear Power Station - Unit 3 05000423 1 OF 3
TITLE (4)
Breaker Mechanism Failure Results in Inoperable Emergency Diesel Generator EVENT DATE (5)
LER NUMBER (6)
REPORT DATE (7)
OTHER FACILITIES INVOLVED (8)
MO DAY YEAR YEAR SEQUENTIAL REV MO DAY YEAR FACILITY NAME DOCKET NUMBER NUMBER NO.
05000 12 26 2001 2002 -
002 -
00 04 11 2002 FACILITY NAME DOCKET NUMBER
_i 05000 OPERATING I
THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply) (11)
MODE (9) 20.2201(b) 20.2203(a)(3)(ii) 50.73(a)(2)(ii)(B) 50.73(a)(2)(ix)(A)
POWER 100 20.2201 (d) 20.2203(a)(4) 50.73(a)(2)(iii) 50.73(a)(2)(x)
LEVEL (10) 20.2203(a)(1) 50.36(c)(1)(i)(A) 50.73(a)(2)(iv)(A) 73.71 (a)(4) 9 20.2203(a)(2)(i) 50.36(c)(1)(ii)(A) 50.73(a)(2)(v)(A) 73.71 (a)(5) k j
20.2203(a)(2)(ii) 50.36(c)(2) 50.73(a)(2)(v)(B)
OTHER 20.2203(a)(2)(iii) 50.46(a)(3)(ii) 50.73(a)(2)(v)(C)
Specify in Abstract below or 20.2203(a)(2)(iv) 50.73(a)(2)(i)(A) 50.73(a)(2)(v)(D) in (if more space is required, use additional copies of NRC Form 366A) (17) because the TS provided for an allowed outage time of 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, because the AC electrical offsite sources and redundant onsite sources remained operable during the period of "B" EDG unavailability, and because no plant work was done to compromise the unit's risk configuration during the time that the EDG was inoperable.
- 4.
Corrective Action
Immediate corrective action was completed on December 28, 2001, to return the "B" EDG to an operable status by installation of a spare 4160 volt breaker. The original "B" EDG breaker that had failed was removed and sent to GE for evaluation. The cause for the breaker's closing latch failure to reset could not be determined.
To prevent recurrence of this condition from causes associated with work practice and omission of relevant information in procedures, the Unit 3 PEO round sheet was updated to include the checking of vital bus breaker indicating lights. A briefing to communicate the work practices surrounding this condition will be completed with the PEOs. Additionally, where determined necessary by review, a restoration step in surveillance procedures that operate the EDG breakers will be included to verify that the EDG breaker springs are charged.
An investigation has been completed and the corrective actions described above will be addressed in accordance with the Millstone Corrective Action Program.
- 5.
Previous Occurrences
No previous similar events/conditions were identified.
Addtional Information Circuit breaker 15G-15U-2 was found racked up with the closing springs not charged.
EPIX Failure Report Number:
340 Component Identification:
Manufacturer:
General Electric Company Model:
AM-4.16-350-2H Generic Model:
AM-4.16-350 Subcategory (Parts List):
Circuit Breaker Voltage Rating Category:
4000 to 5999 VAC Energy Industry Identification System (EIIS) codes are identified in the text as [XXI.