05000333/LER-2010-005, Regarding High Pressure Coolant Injection System Declared Inoperable Due to Power Supply Degradation
| ML103510175 | |
| Person / Time | |
|---|---|
| Site: | FitzPatrick  (DPR-059) |
| Issue date: | 12/16/2010 |
| From: | Bronson K Entergy Nuclear Northeast, Entergy Nuclear Operations |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| JAFP-10-0165 LER 10-005-00 | |
| Download: ML103510175 (5) | |
| Event date: | |
|---|---|
| Report date: | |
| Reporting criterion: | 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)(i)(B), Prohibited by Technical Specifications 10 CFR 50.73(a)(2)(i) 10 CFR 50.73(a)(2)(ii)(A), Seriously Degraded 10 CFR 50.73(a)(2)(ii)(B), Unanalyzed Condition 10 CFR 50.73(a)(2)(iii) 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), Loss of Safety Function 10 CFR 50.73(a)(2)(vii), Common Cause Inoperability 10 CFR 50.73(a)(2)(viii)(A) 10 CFR 50.73(a)(2)(viii)(B) 10 CFR 50.73(a)(2)(ix)(A) 10 CFR 50.73(a)(2)(x) |
| 3332010005R00 - NRC Website | |
text
~.I~t Entergy Nuclear Operations, Inc.
~
James A. FitzPatrick NPP P.O. Box 110 Lycoming, NY 13093 Tel 315-342-3840 Fax 315-349-6480 Kevin Bronson Site Vice President - JAF JAFP-1 0-0165 December 16, 2010 United States Nuclear Regulatory Commission Attn: Document Control Desk Washington, D.C. 20555
SUBJECT:
LER: 201 0-005-00, High Pressure Coolant Injection System Declared Inoperable due to Power Supply Degradation James A. FitzPatrick Nuclear Power Plant Docket No.
50-333 License No.
Dear Sir or Madam:
This report is submitted in accordance with 10 CFR 50.73(a)(2)(v)(B), Any event or condition that could have prevented the fulfillment of the safety function of structures or systems that are needed to remove residual heat.
There is no commitment contained in this report.
Questions concerning this report may be addressed to Mr. Joseph Pechacek, Licensing Manager, at (315) 349-6766.
Sincerely, Kevin Bronson Site Vice President KB/J P/mh
Enclosure:
JAF LER: 2010-005-00, High Pressure Coolant Injection System Declared Inoperable Due to Power Supply Degradation cc:
USNRC, Region 1 USNRC, Project Directorate USNRC, Resident Inspector INPO Document Components:
001 Transmittal Letter with Enclosure
NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION (10-2010)
LICENSEE EVENT REPORT (LER)
APPROVED BY OMB: NO. 3150-0104 EXPIRES: 10/31/2013 Estimated burden per response to comply with this mandatory collection request: 80 hours9.259259e-4 days <br />0.0222 hours <br />1.322751e-4 weeks <br />3.044e-5 months <br />.
Reported lessons learned are incorporated into the licensing process and fed back to industry.
Send comments regarding burden estimate to the FOIA/Privacy Section (T-5 F53), U.S. Nuclear Regulatory Commission, Washington, DC 20555-0001, or by internet e-mail to infocollects.resource@nrc.gov, and to the Desk Officer, Office of Information and Regulatory Affairs, NEOB-10202, (3150-0104), Office of Management and Budget, Washington, DC 20503.
If a means used to impose an information collection does not display a currently valid OMB control number, the NRC may not conduct or sponsor, and a person is not required to respond to, the information collection.
- 1. FACILITY NAME James A. FitzPatrick Nuclear Power Plant
- 2. DOCKET NUMBER 05000333
- 3. PAGE 1 OF 4
- 4. TITLE High Pressure Coolant Injection System Declared Inoperable Due to Power Supply Degradation
- 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 10 23 2010 2010 - 005 -
00 12 16 2010 FACILITY NAME DOCKET NUMBER
- 11. THIS REPORT IS SUBMITTED PURSUANT TO THE REQUIREMENTS OF 10 CFR §: (Check all that apply)
- 9. OPERATING MODE Mode 01
- 10. POWER LEVEL 100 20.2201(b) 20.2201(d) 20.2203(a)(1) 20.2203(a)(2)(i) 20.2203(a)(2)(ii) 20.2203(a)(2)(iii) 20.2203(a)(2)(iv) 20.2203(a)(2)(v) 20.2203(a)(2)(vi) 20.2203(a)(3)(i) 20.2203(a)(3)(ii) 20.2203(a)(4) 50.36(c)(1)(i)(A) 50.36(c)(1)(ii)(A) 50.36(c)(2) 50.46(a)(3)(ii) 50.73(a)(2)(i)(A) 50.73(a)(2)(i)(B) 50.73(a)(2)(i)(C) 50.73(a)(2)(ii)(A) 50.73(a)(2)(ii)(B) 50.73(a)(2)(iii) 50.73(a)(2)(iv)(A) 50.73(a)(2)(v)(A)
X 50.73(a)(2)(v)(B) 50.73(a)(2)(v)(C) 50.73(a)(2)(v)(D) 50.73(a)(2)(vii) 50.73(a)(2)(viii)(A) 50.73(a)(2)(viii)(B) 50.73(a)(2)(ix)(A) 50.73(a)(2)(x) 73.71(a)(4) 73.71(a)(5)
OTHER Specify in Abstract below or in
EVENT DESCRIPTION
On October 23, 2010, at 0023, with the plant operating in Mode 1, at 100% power, Operations personnel identified an acrid odor coming from 23INV-79, High Pressure Coolant Injection (HPCI) [EIIS Identifier: BJ]
Turbine Control and Instrument Power Inverter located in the control room. Further investigation identified what appeared to be discoloration or a 'burned' spot on the inverter cover. Based on these indications, the capability of the HPCI Inverter to perform its safety function was considered to be indeterminate so the inverter was de-energized, the HPCI system declared Inoperable, and Technical Specification (TS) Limiting Condition for Operation (LCO) 3.5.1 Condition C was entered. All other Emergency Core Cooling Systems were verified to be operable. An 8-hour report (EN 46355) to the NRC, in accordance with 10 CFR 50.72(b)(3)(v), was made via the Emergency Notification System at 0254, on October 23, 2010.
An Engineering Change (Equivalent Change EC-25564) was prepared and approved for replacing the degraded inverter with a new inverter. The new replacement inverter was successfully returned to service upon completion of post-maintenance testing activities. On October 23, 2010, at 2054, the HPCI system was declared Operable.
This event is reportable pursuant to 10 CFR 50.73(a)(2)(v)(B), Any event or condition that could have prevented the fulfillment of the safety function of structures or systems that are needed to remove residual heat.
BACKGROUND:
The High Pressure Coolant Injection System is comprised of various components which include pumps, valves, piping, and instrumentation. The function of the HPCI system is to ensure that the reactor is adequately cooled to limit fuel clad temperature in the event of a small break loss of coolant accident (LOCA) which does not result in rapid depressurization of the reactor vessel. The HPCI system permits the plant to be shutdown while maintaining sufficient reactor vessel water inventory until the reactor vessel pressure is low enough to allow the Low Pressure Coolant Injection (LPCI) System [BO] or Core Spray (CS) System [BM] to maintain core cooling.
23INV-79, HPCI Turbine Control & Instrument Power Inverter provides essential power to flow indicating controller 23FIC-108 and other related essential devices for control of the HPCI injection rate.
EVENT ANALYSIS
During James A. FitzPatricks 2010 refueling outage, 23INV-79 failed and was replaced October 10, 2010, with a similar refurbished unit. Thirteen days later, this newly installed refurbished unit, exhibited signs of degradation resulting in the event described in this LER. The cause of the inverter degradation was a degraded internal transformer. An Apparent Cause Evaluation was performed by the Engineering Department to further evaluate the degraded inverter.
There were no signs of the transformer casing being subject to severe physical damage. However, there were minor scrapes on the inverter casing and the mounting brace was skewed due to torsional stresses. Although physical damage is not considered the apparent cause, since the effects of physical damage tend to manifest earlier than thirteen days, it may have been a contributing factor. U.S. NUCLEAR REGULATORY COMMISSION (10-2010)
LICENSEE EVENT REPORT (LER)
CONTINUATION SHEET
- 1. FACILITY NAME
- 2. DOCKET
- 6. LER NUMBER
- 3. PAGE YEAR SEQUENTIAL NUMBER REV N0.
James A. FitzPatrick Nuclear Power Plant 05000333 2010 -
005
- - 00 3 OF 4 There were no other electrical equipment deficiencies downstream of the inverter concurrent with the HPCI Inverter degradation; therefore, anomalies external to the inverter did not contribute to this event.
The degraded Topaz inverter was supplied to JAF in February 1973. A detailed installation history and time-in-service is not available. Based on available information, the inverters transformer is assumed to be an original subcomponent and would, therefore, be approximately 37 years old. According to Electric Power Research Institute (EPRI) EL-5036, Volume 2, Power Transformers, the typical life expectancy of an energized and loaded transformer is between 30 - 40 years. Considering the age and approximate usage, the transformer was likely reaching its end-of-life which led to its degradation.
CAUSE OF EVENT
The Apparent Cause of the HPCI Inverter degradation was age related degradation of a transformer internal to the HPCI Inverter. Although not specifically ruled out as the cause of the transformer degradation, the physical damage to the transformer mounting brace, possibly caused by torsional stresses, may have contributed to the degradation.
EXTENT OF CONDITION:
The Apparent Cause Evaluation identified additional applications for this type of inverter. The replacement of these inverters will be scheduled in accordance with the work management process:
Part ID
Description
Replacement 13INV-152 RCIC Instrument 09-4 Power Inverter Pending: WO 257775 13INV-801B RCIC Instrument 09-21 Power Inverter Pending: WO 257776 06INV-1A Feedwater System Power Inverter Pending: WO 257777 06INV-1B Feedwater System Power Inverter Pending: WO 257778 FAILED COMPONENT IDENTIFICATION:
FitzPatrick Component ID:
23INV-79 Noun Name:
High Pressure Coolant Injection System Instrument Power Supply Inverter Manufacturer / Supplier:
Topaz Electronics / General Electric Model:
N250-GWR-125-60-115 GE Purchase Part Numbers: 145C3027P001 NPRDS manufacturer Code: T248 / G080
CORRECTIVE ACTIONS
Completed Actions:
- 1. Replaced 23INV-79 on 10/23/10. U.S. NUCLEAR REGULATORY COMMISSION (10-2010)
LICENSEE EVENT REPORT (LER)
CONTINUATION SHEET
- 1. FACILITY NAME
- 2. DOCKET
- 6. LER NUMBER
- 3. PAGE YEAR SEQUENTIAL NUMBER REV N0.
James A. FitzPatrick Nuclear Power Plant 05000333 2010 -
005
- - 00 4 OF 4 Open Actions:
- 1. Replace 13INV-152 and 13INV-801B.
ASSESSMENT OF SAFETY CONSEQUENCES
Actual Consequences There were no actual industrial, radiological, or nuclear safety consequences during or as a result of the described period of HPCI inoperability.
Potential Consequences Since the HPCI system passed all of its surveillance tests preceding the event it is presumed Operable prior to the occurrence of this event. Therefore, past operability is not a concern.
The safety significance of the condition was minimal based on the Automatic Depressurization System [SB], the Low Pressure Coolant Injection System, and the Core Spray System being available as emergency core cooling systems. The Reactor Core Isolation Cooling System [BN] was also available as a source of high pressure injection during this period. Additionally, the HPCI system was Inoperable for a period of 20 hours2.314815e-4 days <br />0.00556 hours <br />3.306878e-5 weeks <br />7.61e-6 months <br /> 31 minutes.
This period is well within the TS LCO 3.5.1.C Completion Time of 14 days.
SIMILAR EVENTS
A review of JAF LERs identified only one LER related to 23INV-79 inverter degradation. This previous inverter failure was documented in LER 1996-008. That failure was caused by a shorted capacitor and is, therefore, not similar to the event described in this LER.
In addition, the corrective action program database was reviewed for condition reports associated with inverters supplied under the original or replacement GE Purchase Part Number. Of the identified condition reports none were related to transformer degradation. There were, however, capacitor and transistor age related failures.
REFERENCES:
- 1. Apparent Cause Evaluation Report: 23INV-79 Degradation (CR-JAF-2010-07341)
- 2. EPRI Report EL-5036, Power Transformers
- 3. JAF Updated Final Safety Analysis Report: Section 6.4.1, High Pressure Coolant Injection System