05000219/LER-2004-003, Regarding Actuation of Reactor Protection System Due to Spurious HI-HI Trip Signals on Intermediate Range Monitors Caused by Electromagnetic Interference

Regarding Actuation of Reactor Protection System Due to Spurious HI-HI Trip Signals on Intermediate Range Monitors Caused by Electromagnetic Interference

ML042100402
Person / Time
Site:	Oyster Creek
Issue date:	07/22/2004
From:	Swenson C AmerGen Energy Co
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
2130-04-20144 LER 04-003-00
Download: ML042100402 (4)

LER-2004-003, Regarding Actuation of Reactor Protection System Due to Spurious HI-HI Trip Signals on Intermediate Range Monitors Caused by Electromagnetic Interference

Event date:
Report date:
Reporting criterion:	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 10 CFR 50.73(a)(2)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(i) 10 CFR 50.73(a)(2)(viii)(A) 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2)(viii)(B)
2192004003R00 - NRC Website

text

AkerGen SM

-. ArerGen Energy Company, LLC Oyster Creek US Route 9 South. RO. Box 388 Forked River, NJ 08731-0388 n.^

AA}^tO^tN Bonn A

a.

.1_

red Wwwvexelumurecl mLI1 An Exelon Company 10 CFR 50.73 July 22, 2004 2130-04-20144 U. S. Nuclear Regulatory Commission Attn: Document Control Desk Washington, DC 20555 - 0001 Oyster Creek Generating Station Facility Operating License No. DPR-1 6 NRC Docket No. 50-219

Subject:

Licensee Event Report 2004-003-00: Actuation of Reactor Protection System due to Spurious HI-HI Trip Signals on Intermediate Range Monitors Caused by Electromagnetic Interference Enclosed is Licensee Event Report 2004-003, Revision 0. This event did not affect the health and safety of the public or plant personnel.

If any further information or assistance is needed, please contact David Fawcett at 609-971-4284.

C. N. Swenso Vice President, Oyster Creek Generating Station CNS/DIF Enclosure cc:

H. J. Miller, Administrator, USNRC Region I P. S. Tam, USNRC Senior Project Manager, Oyster Creek R. J. Summers, USNRC Senior Resident Inspector, Oyster Creek File No. 04106

a_-o

_
Jj Z_'

NRC FORM 366 U.S. NUCLEAR REGULATORY APPROVED BY OMB NO. 3150-0104 EXPIRES 7-31-2004 (7-2001)

COMMISSION digits/characters for each block) the NRC may not conduct or sponsor, and a person Is not required to respond to. the infomnation collection.

3. PAGE Oyster Creek, Unit 1 05000219 1

OF 3

4. TITLE Actuation of Reactor Protection System due to Spurious Hi-Hi Trip Signals on Intermediate Range Monitors Caused by Electromagnetic Interference

5. EVENT DATE

6. LER NUMBER

7. REPORT DATE

8. OTHER FACILITIES INVOLVED MO DAY YEAR YEAR SEQUENTIALI REV MO DAY YEAR FACILITY NAME DOCKET NUMBER NUMBER NO 05000 05 27 2004 2004 003 - 00 07 22 2004 FACILITY NAME DOCKET NUMBER J 05000

9. OPERATING N1.

THIS REPORTIS SUBMr TED PURSUANTTO THE REQUIREMENTS OF 10 CFR §: (Check all that apply)

MODE N

10. POWER 002

_ 20.2201(b) 20.2203(a)(3)(ii)

_ 50.73(a)(2)(ii)(B) 50.73(a)(2)(ix)(A)

LEVEL 20.2201 (d) 20.2203(a)(4) 50.73(a)(2)(iii) 50.73(a)(2)(x) 20.2203(a)(1)

_ 50.36(c)(1)(i)(A)

X 50.73(a)(2)(iv)(A)

_ 73.71 (a)(4) 20.2203(a)(2)(i)

_ 50.36(c)(1 )(ii)(A) 50.73(a)(2)(v)(A) 73.71 (a)(5) 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) 20.2203(a)(2)(iv)

_50.73(a)(2)(i)(A) 50.73(a)(2)(v)(D) 20.2203(a)(2)(v) 50.73(a)(2)(i)(B)

_50.73(a)(2)(vii) 20.2203(a)(2)(vi) 50.73(a)(2)(i)(C) 50.73(a)(2)(viii)(A) 20.2203(a)(3)(i) 50.73(a)(2)(ii)(A) 50.73(a)(2)(viii)(B)

12. LICENSEE CONTACT FOR THIS LER NAME TELEPHONE NUMBER (Include Area Code)

David Fawcett, Licensing Engineer 1

(609) 971-4284On May 27, 2004, at 00:31 hours, with the Reactor Mode switch in the Startup position, a Reactor scram from approximately 2% power was caused by a spurious actuation of Intermediate Range Neutron Monitor (IRM) channels 13, 14, and 18. The spurious actuation was caused by electromagnetic interference. The EMI affected the IRM channels due to loose connections, damaged cabling, and deficiencies in grounding. The reactor shut down as designed.

The safety significance of this event is considered minimal. The plant responded as designed for this type of event.

Technical Specification limits were maintained. There was no radioactive release. All safety systems were fully operable. Off-site power was available. Operator performance was satisfactory.

Connections were tightened, damaged cabling was repaired, and one IRM pre-amplifier was replaced.

NRC FORM 366 V-2001)

(If more space is required, use additional copies of (If more space is required, use additional copies of NRC Form 366A)

Additional Information

A.

Failed Components:

None

B. Previous similar events

LER 92-007-00, Reactor Scram Caused by Electrical Noise from a Failed IRM Bypass Switch During Plant Startup There have been additional cases of IRM spiking problems, but they did not result in a reactor scram while the reactor was critical. An IRM spiking trend has been identified through the Corrective Action Program. A root cause evaluation is in progress.

C.

Identification of components referred to in this Licensee Event Report:

Components IEEE 805 System ID IEEE 803A Function Neutron Monitors IG RI