05000352/LER-2011-002, Regarding Automatic Actuation of the Reactor Protection System Due to a Main Turbine Trip

Regarding Automatic Actuation of the Reactor Protection System Due to a Main Turbine Trip

ML112140258
Person / Time
Site:	Limerick
Issue date:	08/02/2011
From:	Maguire W Exelon Generation Co, Exelon Nuclear
To:	Document Control Desk, Office of Nuclear Reactor Regulation
References
LER 11-002-00
Download: ML112140258 (5)

LER-2011-002, Regarding Automatic Actuation of the Reactor Protection System Due to a Main Turbine Trip

Event date:
Report date:
Reporting criterion:	10 CFR 50.73(a)(2)(iv)(A), System Actuation 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)(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
3522011002R00 - NRC Website

text

10CFR50.73 August 2, 2011 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555-0001 Limerick Generating Station, Unit 1 Facility Operating License No. NPF-39 NRC Docket No. 50-352

Subject:

LER 2011-002-00, Automatic Actuation of the Reactor Protection System Due To a Main Turbine Trip This Licensee Event Report (LER) addresses an automatic actuation of the reactor protection system due to a main turbine trip. The main turbine tripped due to an actuation of the reactor vessel high level trip logic during surveillance testing. The high level trip actuation was due to use of an incompatible volt-ohm meter to verify the state of the opposite high level trip logic channels prior to introducing trip signals during the test. The root cause of the event was the reactor vessel high level trip calibration and functional surveillance test revisions did not fully assess the impacts of the test equipment on the direct current turbine trip circuit.

This LER is being submitted pursuant to the requirements of 10CFR50.73(a)(2)(iv)(A).

There are no commitments contained in this letter.

If you have any questions, please contact John Hunter III at (610) 718-3400.

Respectfully, Original signed by Peter A. Gardner for William F. Maguire Vice President - Limerick Exelon Generation Company, LLC cc: Administrator Region I, USNRC USNRC Senior Resident Inspector, LGS

NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION (10-2010)

LICENSEE EVENT REPORT (LER)

(See reverse for required number of digits/characters for each block)

APPROVED BY OMB: NO. 3150-0104 EXPIRES: 10/31/2013

, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.

1. FACILITY NAME Limerick Generating Station, Unit 1

2. DOCKET NUMBER 05000352

3. PAGE 1 OF 4

4. TITLE Automatic Actuation Of The Reactor Protection System Due To A Main Turbine Trip

5. EVENT DATE

6. LER NUMBER

7. REPORT DATE

8. OTHER FACILITIES INVOLVED MONTH DAY YEAR YEAR SEQUENTIAL NUMBER REV NO.

MONTH DAY YEAR FACILITY NAME DOCKET NUMBER 05000 06 03 2011 2011 - 002 - 00 08 02 2011 FACILITY NAME DOCKET NUMBER 05000

9. OPERATING MODE 1

10. POWER LEVEL 100

11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply) 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)(1) 20.2203(a)(4) 50.73(a)(2)(ii)(B) 50.73(a)(2)(viii)(B) 20.2203(a)(2)(i) 50.36(c)(1)(i)(A) 50.73(a)(2)(iii) 50.73(a)(2)(ix)(A) 20.2203(a)(2)(ii) 50.36(c)(1)(ii)(A) 50.73(a)(2)(iv)(A) 50.73(a)(2)(x) 20.2203(a)(2)(iii) 50.36(c)(2) 50.73(a)(2)(v)(A) 73.71(a)(4) 20.2203(a)(2)(iv) 50.46(a)(3)(ii) 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) 50.73(a)(2)(i)(B) 50.73(a)(2)(v)(D)

Specify in Abstract below or in LICENSEE EVENT REPORT (LER)

CONTINUATION SHEET Component data:

System:

Electro-hydraulic Control Component:

10-C663 Panel, EHC, Turbine Manufacturer:

G080 General Electric Company Model:

838E408