05000400/LER-2007-003, Automatic Reactor Trip Following Actuation of a Sudden Pressure Relay and Lockout of the 1A Startup Transformer (SUT)
| ML073320172 | |
| Person / Time | |
|---|---|
| Site: | Harris  |
| Issue date: | 11/19/2007 |
| From: | Henderson K Progress Energy Carolinas |
| To: | Document Control Desk, Office of Nuclear Reactor Regulation |
| References | |
| HNP-07-163 LER 07-003-00 | |
| Download: ML073320172 (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 |
| 4002007003R00 - NRC Website | |
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Progress Energy NOV 1 9 2007 Serial: HNP-07-163 10 CFR 50.73 U.S. Nuclear Regulatory Commission ATTN: NRC Document Control Desk Washington, DC 20555 SHEARON HARRIS NUCLEAR POWER PLANT UNIT 1 DOCKET NO. 50-400/LICENSE NO. NPF-63 LICENSEE EVENT REPORT 2007-003-00 Ladies and Gentlemen:
The enclosed Licensee Event Report 2007-003-00 is submitted in accordance with 10 CFR 50.73. This report describes an automatic reactor/turbine trip following actuation of a sudden pressure relay and loss of the "1A" Startup Transformer.
Event notification EN 43676 previously reported this event on September 29, 2007 in accordance with 10 CFR 50.72.
Please refer any questions regarding this submittal to Mr. Dave Corlett, Supervisor -
Licensing/Regulatory Programs, at (919) 362-3137.
Sincerely, Kelvin Henderson Plant General Manager Harris Nuclear Plant KH/khv Enclosure cc:
Mr. P. B. O'Bryan, NRC Sr. Resident Inspector Ms. M. G. Vaaler, NRC Project Manager Dr. W. D. Travers, NRC Regional Administrator Progress Energy Carolinas, Inc.
Harris Nuclear Plant P. 0. Box 165 New Hill, NC 27562
~~1 ~
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION APPROVED BY OMB: NO. 3150-0104 EXPIRES: 08/31/2010 (9-2007)
, the NRC may not conduct digits/characters for each block) or sponsor, and'a person is not required to respond to, the information digis/carater foreac blck)collection.
- 13. PAGE Harris Nuclear Plant - Unit 1 050004001 1 OF 3
,. TITLE Automatic Reactor Trip following Actuation of a Sudden Pressure Relay and Lockout of the 1A Startup Transformer (SUT)
- 5. EVENT DATE
- 6. LER NUMBER
- 7. REPORT DATE
- 8. OTHER FACILITIES INVOLVED MONTH DAY YEAR YEAR SEQUENTIAL REV MONTH DAY YE FACILITY NAME DOCKET NUMBER YEAR NUMBER NO.
A N/A 05000 IFACILITY NAME DOCKET NUMBER 09 28 2007 2007 003 00 11 19 2007 N/A 05000
- 9. OPERATING MODE
- 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR§: (Check all that apply)
[l 20.2201(b)
El 20.2203(a)(3)(i)
El 50.73(a)(2)(i)(C)
C3 50.73(a)(2)(vii)
El 20.2201(d)
El 20.2203(a)(3)(ii)
[I 50.73(a)(2)(ii)(A)
[I 50.73(a)(2)(viii)(A)
[I 20.2203(a)(1) 0l 20.2203(a)(4)
El 50.73(a)(2)(ii)(B)
El 50.73(a)(2)(viii)(B)
El 20.2203(a)(2)(i)
El 50.36(c)(1)(i)(A) 0l 50.73(a)(2)(iii)
El 50.73(a)(2)(ix)(A)
- 10. POWER LEVEL El 20.2203(a)(2)(ii)
El 50.36(c)(1)(ii)(A)
ED 50.73(a)(2)(iv)(A)
El 50.73(a)(2)(x)
[I 20.2203(a)(2)(iii)
El 50.36(c)(2)
El 50.73(a)(2)(v)(A)
El 73.71(a)(4)
[I 20.2203(a)(2)(iv)
El 50.46(a)(3)(ii)
El 50.73(a)(2)(v)(B)
El 73.71(a)(5) 027 [E 20.2203(a)(2)(v)
El 50.73(a)(2)(i)(A)
El 50.73(a)(2)(v)(C)
[E OTHER El 20.2203(a)(2)(vi)
El 50.73(a)(2)(i)(B)
[E 50.73(a)(2)(v)(D)
Specify in Abstract below or in
III. SAFETY SIGNIFICANCE
This event is not significant because the Reactor Protection System [JC] functioned as designed. This event is noteworthy because a single component malfunction caused a reactor and turbine trip.
Actual Safety Consequences:
The transient was an automatic reactor trip from 27 percent power generated by logic for a RCP Underfrequency due to a loss of Auxiliary buses 1A-NNS, 1C-NNS and 1D-NNS. Although only one train (fed from the 'A' Startup Transformer) of non-emergency power was lost, this event is bounded by a Loss of Non-emergency AC Power to the Station Auxiliaries which-is analyzed in the HNP FSAR Section 15.2. A Loss of Non-emergency AC Power to the Station Auxiliaries is classified as an American Nuclear Society (ANS) Condition II event - a fault of moderate frequency. The plant is designed for this type of event and responded as expected. The initial plant conditions prior to the trip were well within the bounding conditions for the plant design. The plant attained normal operating no-load temperature and pressure, and no unusual conditions were observed for plant equipment following the event. All safety equipment functioned as required. The 'A' EDG started andloaded the
'A' safety buses (as designed). No additional or compensatory measures were required for this event. The operating staff performed the required actions for the trip. Other than the transient induced by the trip, there are no adverse safety consequences.
Potential Safety Consequences:
The potential safety consequences under alternate conditions are bounded by the FSAR Chapter 15 events.
IV. PREVIOUS SIMILAR EVENTS
The Qualitrol 930 two-out-of-three sudden pressure relay misoperation experienced at Harris is a first of a kind event in the industry for this model relay.
V, CORRECTIVE ACTIONS Completed corrective actions include replacing the Qualitrol 930 series relay with the Qualitrol 900 series relay and conducting testing to validate that the "1A" SUT was not damaged. Additional corrective actions are to use a temporary modification togather data on the "1A" SUT to determine operating margin and implement appropriate design changes to the sudden pressure relays on the SUTs.
VI. COMMITMENTS
This document contains no new regulatory commitments.