05000219/LER-2009-003, Regarding Manual Reactor Shutdown Caused by Loss of Cooling to the Main Transformer
| ML091670097 | |
| Person / Time | |
|---|---|
| Site: | Oyster Creek |
| Issue date: | 06/10/2009 |
| From: | Rausch T Exelon Corp, Exelon Nuclear |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| RA-09-046 LER 09-003-00 | |
| Download: ML091670097 (4) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 10 CFR 50.73(a)(2)(i) 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 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)(iii) 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)(i)(A), Completion of TS Shutdown 10 CFR 50.73(a)(2)(v), Loss of Safety Function 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications |
| 2192009003R00 - NRC Website | |
text
Exelkn Oyster Creek Generating Station www.exeloncorp.com Nuclear Route 9 South PO Box 388 Forked River, NJ o8731 10 CFR 50.73 June 10, 2009 RA-09-046 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555 - 0001 Oyster Creek Nuclear Generating Station Facility Operating License No. DPR-16 NRC Docket No. 50-219
Subject:
Licensee Event Report (LER) 2009-003-00, Manual Reactor Shutdown Caused by Loss of Cooling to the Main Transformer Enclosed is Licensee Event Report 2009-003-00, Manual Reactor Shutdown Caused by Loss of Cooling to the Main Transformer. This event did not affect the health and safety of the public or plant personnel. This event did not result in a safety system functional failure. There are no new regulatory commitments made in this LER submittal.
If any further information or assistance is needed, please contact James Barstow, Regulatory Assurance Manager at 609-971-4947.
Sincerely, T.S. Rausch Vice President, Oyster Creek Nuclear Generating Station
Enclosure:
NRC Form 366, LER 2009-003-00 cc:
Regional Administrator, USNRC Region I USNRC Project Manager, Oyster Creek USNRC Senior Resident Inspector, Oyster Creek File No. 09054 ZiE-7--ggO
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 08/31/2010 (9-2007)'
, the NRC may digits/characters for each block) not conduct or sponsor, and a person is not required to respond to, the informntion n.nilh=tinn
- 3. PAGE Oyster Creek, Unit 1 05000219 1 OF 3
- 4. TITLE Manual Reactor Shutdown Caused by Loss of Cooling to the Main Transformer
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
[
- 8. OTHER FACILITIES INVOLVED FACILITY NAME DJOCKET NUMBER MONTH DAY YEAR YEAR SEQUENTIAL REV MONTH DAY YEAR N/A N/A NUMBER NO.I IFACILITY NAME DOCKET NUMBER 04 25 2009 2009 -003-00 6
10 20091 N/A N/A
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply)
[o 20.2201(b)
El 20.2203(a)(3)(i)
El 50.73(a)(2)(i)(C)
[I 50.73(a)(2)(vii)
N El 20.2201(d)
[I 20.2203(a)(3)(ii)
[I 50.73(a)(2)(ii)(A)
[I 50.73(a)(2)(viii)(A) 0l 20.2203(a)(1)
El 20.2203(aX4)
[I 50.73(a)(2)(ii)(B)
El 50.73(a)(2)(viii)(B)
E_ 20.2203(a)(2)(i)
[I 50.36(c)(1)(i)(A)
[I 50.73(a)(2)(iii)
-] 50.73(a)(2)(ix)(A)
- 10. POWER LEVEL [I 20.2203(a)(2)(ii)
[I 50.36(c)(1)(ii)(A) 0 50.73(a)(2)(iv)(A)
El 50.73(a)(2)(x)
[I 20.2203(a)(2)(iii)
[I 50.36(c)(2)
El 50.73(a)(2)(v)(A)
El 73.71(a)(4) 100 El 20.2203(a)(2)(iv)
[I 50.46(a)(3)(ii)
El 50.73(a)(2)(v)(B)
El 73.71 (a)(5)
El 20.2203(a)(2)(v)
[I 50.73(a)(2)(i)(A)
[I 50.73(a)(2)(v)(C)
El OTHER [I 20.2203(a)(2)(vi)
Cl 50.73(a)(2)(i)(B)
El 50.73(a)(2)(v)(D)
Specify in Abstract below or in
Corrective Actions
The M1A Main Power Transformer, replaced in February 2009, was supplied to Oyster Creek from the Eddystone Generating Station. There is no pertinent equipment history information for this auxiliary control power transformer or the motor starter, contactor coil. The control power transformer and the #1 cooling bank motor starter assembly were replaced, properly rated fuses were installed, and the cooling system control circuitry was modified to have a backup independent power supply to address a single point vulnerability. In order to prevent future similar failures and eliminate another single point vulnerability, modifications were performed for the cooling circuits on both Main Power Transformers (M1A and M1 B). These modifications added individual fuses for each cooling group and coordinated the rating of the control power fuses such that only one cooling group circuit is lost on an electrical fault within that same cooling group circuitry.
The plant returned to power operation on March 2, 2009.
Additional enhancements were incorporated into the Alarm Response Procedures. Guidance was provided for the maximum allowable operation time for a total loss of cooling to the main transformers and actions to take in an attempt to restore cooling power.
Previous Occurrences
There have been no similar Licensee Event Reports events at Oyster Creek in the last three years, involving a loss of a main transformer's cooling system leading to a reactor scram.
Component Failure Data
Component: Motor Starter (CR1 06CO02AA with a 15D21 G2 contactor coil)
Manufacturer: GE (Supplied with the main transformer from the Eddystone Generating Station)
Serial No: N/A
Cause
Faulted (shorted coil)
Component: Control Power Transformer (460/115 VAC, 0.500KVA - MOD# 9T55Y50)
Manufacturer: GE (Supplied with the main transformer from the Eddystone Generating Station)
Serial No: N/A
Cause
Overload failure of its windingsPRINTED ON RECYCLED PAPERPRINTED ON RECYCLED PAPER