View source for CP-201000074, State of New York (NYS) Pre-Filed Evidentiary Hearing Exhibit NYS000026, Luminant Power (CP-201000074), Log TXX-10010), Licensee Event Report 445/10-001-00, Trip Due to Pressure Relay Actuation on Main Transformer 01, Comanche Peak Nu

{{Adams
| number = ML11346A534
| issue date = 03/03/2010
| title = State of New York (NYS) Pre-Filed Evidentiary Hearing Exhibit NYS000026, Luminant Power (CP-201000074), Log # TXX-10010), Licensee Event Report 445/10-001-00, Trip Due to Pressure Relay Actuation on Main Transformer 01, Comanche Peak Nuclea
| author name = Madden F
| author affiliation = Luminant Generation Co, LLC, Luminant Power
| addressee name = 
| addressee affiliation = NRC/Document Control Desk, NRC/NRR
| docket = 05000286, 05000247
| license number = 
| contact person = SECY RAS
| case reference number = RAS 21523, 50-247-LR, 50-286-LR, ASLBP 07-858-03-LR-BD01, CP-201000074
| document report number = LER 10-001-00
| document type = Legal-Pre-Filed Exhibits
| page count = 5
}}

=Text=
{{#Wiki_filter:I.I Luminant CP-201000074 Log # TXX-10010 March 3, 2010 u. S. Nuclear Regulatory Commission ATTN: Document Control Desk Washington, DC 20555 Rafael Flores Senior Vice President 
& Chief Nuclear Officer rafael.fiores@Luminant.com Luminant Power POBox 1002 6322 North FM 56 Glen Rose. TX 76043 T 254 897 5550 C 817 559 0403 F 254 897 6652 Ref. # 10CFR50.73(a)(2)(iv) (A) 

==SUBJECT:==
COMANCHE PEAK NUCLEAR POWER PLANT DOCKET NO. 50-445 LICENSEE EVENT REPORT 445/10-001-00, UNIT 1 TRIP DUE TO PRESSURE RELAY ACTUA nON ON MAIN TRANSFORMER 01 

==Dear Sir or Madam:==
Pursuant to 10CFR50.73(a)(2)(iv)(A), Luminant Generation Company LLC (Luminant Power) hereby submits enclosed License Event Report (LER) 445/10-001-00, Unit 1 trip due to pressure relay actuation on Main Transformer
: 01. This event did not result in a safety system functional failure. This event did not affect the health and safety of the public or plant personneL This communication contains no licensing basis commitments regarding Comanche Peak Units 1 and 2. Should you have any questions, please contact Ms. Tamera J. Ervin-Walker at (254)897-6902.
Sincerely, Luminant Generation Company LLC Rafael Flores By. 4!! Y!Y1-Fred W. Madden Director, Oversight 
& Regulatory Affairs TJEW Enclosure 
-LER 445/10-001-00 c -E. E. Collins, Region IV B. K. Singal, NRR Resident Inspectors, Comanche Peak A member of the STARS (Strategic Teaming and Resource Sharing) Alliance Callaway . Comanche Peak . Diablo Canyon . Palo Verde . San' Onofre . South Texas Project . Wolf Creek 1 OAGI0001044_00001  
" .,' .1 '.,.' * ,'1.."-", .' .... "'t *.. ,',, *. ,'. NRC FORM 366 U.S. NUCLEAR REGULATORY COMMISSION BY OMB NO. 3150-0104 EXPIRES: (9-2007) Estimated burden per response to comrely with this mandatory collection request: 80 hours. Reported lessons earned are incorporated into the licensing process and fed back to industry.
Send comments burden LICENSEE EVENT REPORT (LER) estimate to the Records and FOINPrivacy Service Branch l -5 F 2), U.S .. Nuclear Commission, Washington, DC 20555-000 , or br. internet e-mail to in and to the Desk Officer, Office of In ormation (See reverse for required number of and Regulatory Affairs, NE B-10202 (3150-0104), Office of Management and Budget, Washington, DC 20503. If a means used to impose an information digits/characters for each block) collection does not display a currently valid OMB control number, the NHC may not conduct or sponsor, and a person is not required to respond to, the information collection.
: 1. FACILITY NAME 2. DOCKET NUMBER 3. PAGE Comanche Peak Nuclear Power Plant 05000 445 1 OF 4 4. TITLE UNIT 1 TRIP DUE TO PRESSURE RELAY ACTUATION ON MAIN TRANSFORMER 01 5. EVENT DATE 6. LER NUMBER 7. REPORT DATE 8. OTHER FACILITIES INVOLVED MONTH DAY YEAR YEAR I SEQUENTIAL REV MONTH DAY YEAR FACILITY NAME DOCUMENT NUMBER NUMBER NO. NIA 05000 01 09 2010 2010 --001 --0 03 03 2010 FACILITY NAME DOCUMENT NUMBER 05000 9. OPERATING MODE 11. THIS REPORT IS SUBMITIED PURSUANT TO THE REQUIREMENTS OF 10 CFR &sect;: (Check all that apply) 0 20.2201 (b) 0 20.2203(a)(3)(i) 0 50.73(a)(2)(i)(C) 0 50.73(a)(2)(vii) 1 0 20.2201 (d) D 20.2203(a)(3)(ii) 0 50.73(a)(2)(ii)(A) 0 50.73(a)(2)(viii)(A) 0 20.2203(a)(1 ) D 20.2203(a)(4 ) 0 50.73(a)(2)(ii)(8)
B 50.73(a)(2)(viii)(8) 0 20.2203(a)(2)(i)
D 50.36(c)(1 
)(i)(A) 0 50.73(a)(2)(iii) 50.73(a)(2)(ix)(A)
: 10. POWER LEVEL 0 20.2203(a)(2)(ii) 0 50.36(c)(1 
)(ii)(A) [K] 50.73(a)(2)(iv)(A) 0 50.73(a)(2)(x) 0 20.2203(a)(2)(iii) 0 50.36(c)(2)
D 50.73(a)(2)(v)(A) 0 73.71 (a)(4) D 20.2203(a)(2)(iv) 0 50.46(a)(3)(ii)
D 50.73(a)(2)(v)(8) 0 73.71 (a)(5) 0 20.2203(a)(2)(v) 0 50.73(a)(2)(i)(A)
D 50.73(a)(2)(v)(C) 0 OTHER 100 0 20.2203(a)(2)(vi) 0 50.73(a)(2)(i)(8)
D 50.73(a)(2)(v)(D)
VOLUNTARY LER 12. LICENSEE CONTACT FOR THIS LER FACILITY NAME I TELEPHONE NUMBER (Include Area Code) Timothv A. Hope Nuclear Licensinq Manaqer 254-897 -6370 13. COMPLETE ONE LINE FOR EACH COMPONENT FAILURE DESCRIBED IN THIS REPORT CAUSE SYSTEM COMPONENT MANU-REPORTABLE I CAUSE SYSTEM COMPONENT MANU-REPORTABLE FACTURER TO EPIX FACTURER TO EPIX X EL XFMR ABB Y . 14. SUPPLEMENTAL REPORT EXPECTED 15. EXPECTED MONTH DAY YEAR D GJ NO SUBMISSION YES (If yes, complete 15. EXPECTED SUBMISSION DATE) DATE ABSTRACT (Limit to 1400 spaces, i.e., approximately 15 single-spaced typewritten lines) On January 9, 2010, Comanche Peak Nuclear Power Plant (CPNPP) Unit 1 was in Mode 1 operating at 100% power. At 1028 hours, the Unit 1 Main Turbine tripped due to a pressure relay actuation on the Unit 1 Main Transformer 01 and the Main Turbine Trip caused an automatic reactor trip. All control rods fully inserted, and all Auxiliary Feedwater pumps started as expected as a result of the reactor trip. All systems responded normally during and following the event. Internal inspection of the transformer showed that the relay actuation resulted from an internal failure of the Main Transformer as a result of a phase to ground fault. The exact cause of the fault could not be determined.
Immediate corrective actions included isolating the Main Transformer 01 from Unit 1 and the other Main Transformer
: 02. On January 11, 2010, Unit 1 was synchronized to the grid at 0011 hours and reached a 640 megawatt output by 2100 hours. On January 19, 2010, a planned outage was taken on Unit 1 to install a spare transformer.
Unit 1 was synchronized to the grid on January 21,2010 at 2326 hours and reached 100% power the next day at 1341 hours. All times in this report are approximate and are Central Standard Time unless noted otherwise.
NRC FORM 366 (9-2007) PRINTED ON RECYCLED PAPER OAGI0001044_00002 NRC FORM 366A (9-2007) u.s. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER) CONTINUATION SHEET 1. FACILITY NAME Comanche Peak Nuclear Power Plant 2. DOCKET 05000 -445 NARRATIVE (If more space is required, use additional copies of NRC Form 366A) (17) I. DESCRIPTION OF THE REPORTABLE EVENT A. REPORTABLE EVENT CLASSIFICATION:
YEAR 6. LER NUMBER I SEQUENTIAL I NUMBER 2010 --001 --REV NO. 00 3. PAGE 2 OF 4 10CFR50.73(a)(2)(iv)(A) "Any event or condition that resulted in a manual or automatic actuation of any of the systems listed in paragraph (a)(2)(iv)(B)." B. PLANT CONDITION PRIOR TO EVENT: On January 9,2010, CPNPP Unit 1 was in Mode 1, operating at 100% power. C. STATUS OF STRUCTURES, SYSTEMS, OR COMPONENTS THAT WIERE INOPERABLE AT THE START OF THE EVENT AND THAT CONTRIBUTED TO THE EVENT There were no inoperable structures, systems, or components that contributed to the event. D. NARRATIVE 

==SUMMARY==
OF THE EVENT, INCLUDING DATES AND APPROXIMATE TIMES: On January 9,2010, CPNPP Unit 1 was in Mode 1 operating at 100% power.At 1028 hours, the Unit 1 Main Turbine tripped due to a pressure relay [EllS: (RL V)] actuation on the Unit 1 Main Transformer 01 [EllS: (XFMR)] and the Main Turbine Trip caused an automatic reactor trip. All control rods fully inserted and all three Auxiliary Feedwater pumps [EllS: (BA)(P)] started as expected as a result of the reactor trip. All systems responded normally during and following the event. There were no safety consequences impacting plant or public safety as a result of this event. In the Control Room (CR), the following alarms were received at 1028 (in order): 72 Generator . Lockout Relay 82-2/1 G Trip, 70 Generator Lockout Relay 86-1/1 G Trip, 98 Generator Off the Load Rejection Protection, 24 Turbine Trip & P9 Reactor Trip, 97 Turbine trip, and 92 CROS Breakers 52/RTA & RTB open. These alarms were followed by a normal plant trip response.
The Unit 1 Main Transformer 01 is an ABB transformer and is one of two Unit 1 main generator output transformers designed to step-up the three-phase, 22-thousand volts (kV) output by the generator to 345kV for power transmission to the electric power grid. The other Unit 1 Main Transformer 02 is also manufactured by ABB. Immediate corrective actions included isolating the Main Transformer 01 from Unit 1 and the other Main Transformer
: 02. On January 11, 2010, Unit 1 was synchronized to the grid at 0011 hours and reached a 640 megawatt output by 2100 hours. E. THE METHOD OF DISCOVERY OF EACH COMPONENT OR SYSTEM FAILURE, OR PROCEDURAL PERSONNEL ERROR Operators (utility, licensed) in the Unit 1 CR received a Unit 1 Main Transformer 01 pressure alarm. NRC FORM 366A (9-2007) PRINTED ON RECYCLED PAPER 1 OAGI0001044_00003 NRC FORM 366A (9-2007) u.s. NUCLEAR REGULATORY COMMISSION LICENSEE EVENT REPORT (LER) CONTINUATION SHEET 1. FACILITY NAME Comanche Peak Nuclear Power Plant 2. DOCKET 05000 -445 YEAR 6. LER NUMBER I SEQUENTIAL I NUMBER REV NO. 3. PAGE 2010 --001 --00 3 OF 4 NARRATIVE (If more space is required, use additional copies of NRC Form 366A) (17) II. COMPONENT OR SYSTEM FAILURES A. CAUSE OF EACH COMPONENT OR SYSTEM FAILURE There was an internal phase to ground fault on Unit 1 Main Transformer 01 that could not be rectified.
The exact cause of the fault could not be determined.
B. FAILURE MODE, MECHANISM, AND EFFECTS OF EACH FAILED COMPONENT The Unit 1 Main Turbine tripped due to a pressure relay actuation on the Unit 1 Main Transformer 01 and the Main Turbine Trip caused an automatic reactor trip. C. SYSTEMS OR SECONDARY FUNCTIONS THAT WERE AFFECTED BY FAILURE OF COMPONENTS WITH MULTIPLE FUNCTIONS Not applicable 
-The component that failed did not have any multiple functions.
D. FAILED COMPONENT INFORMATION Manufactured by ABB POWER T&D CO 20.9/345kV, Three phase, Main Transformer III. ANALYSIS OF THE EVENT A. SAFETY SYSTEM RESPONSES THAT OCCURRED Both Motor Driven Auxiliary Feedwater Pumps and the Turbine Driven Auxiliary Feedwater Pump started as expected as a result of the reactor trip. B. DURATION OF SAFETY SYSTEM TRAIN INOPERABILITY Not applicable 
-there was no safety system train inoperability that resulted from this event. C. SAFETY CONSEQUENCES AND IMPLICATIONS OF THE EVENT This event is bounded by the CPNPP Final Safety Analysis Report (FSAR) accident analysis which assumes conservative initial conditions which bound the plant operating range and other assumptions which could reduce the capability of safety systems to mitigate the consequences of the transient.
This event is bounded by the analysis of the Turbine trip presented in Section 15.2.3 of the CPNPP FSAR. The analysis uses a conservative assumption to demonstrate the capability of pressure relieving devices and to demonstrate core protection margins. The event of January 9, 2010, occurred at 100% reactor power, and all systems and components functioned as designed.
NRC FORM 366A (9*2007) PRINTED ON RECYCLED PAPER OAG10001044_00004 NRC FORM 366A (9-2007) 1. FACILITY NAME LICENSEE EVENT REPORT (LER) CONTINUATION SHEET 2. DOCKET Comanche Peak Nuclear Power Plant 05000 -445 NARRATIVE (If more space is required, use additional copies of NRC Form 366A) (17) u.s. NUCLEAR REGULATORY COMMISSIO J 6. LER NUMBER 3. PA.GE l YEAR I SEQUENTIAL I REV NUMBER NO. 2010 --001 --00 4 OF 4 Based on the above, it is concluded that the health and safety of the public were unaffected by this condition and this event has been evaluated to not meet the definition of a.safety system functional failure per 10CFRSO.73(a)(2)(v).
IV. CAUSE OF THE EVENT On January 9,2010, CPNPP Unit 1 was in Mode 1 operating at 100% power. At 1028 hours, the Unit 1 Main Turbine tripped due to a pressure relay actuation on the Unit 1 Main Transformer 01 and the Main Turbine Trip caused an automatic reactor trip. Internal inspection of the transformer showed that the relay actuation resulted from an internal failure of the transformer that could not be rectified.
The specific cause could not be determined.
Subsequent oil testing revealed high levels of gasses. Since the transformer was shell form, the windings are horizontal and only the top half was visible. There was also evidence of movement in the H1 and H2 windings, the insulating material was distorted, the blocks were broken loose, and carbon had covered the windings and visible structures.
There was no evidence of a problem with the lead assemblies or bushings.
V. CORRECTIVE ACTIONS Immediate corrective actions included isolating Main Transformer 01 from Unit 1 and the other Main Transformer
: 02. On January 11, 2010, Unit 1 was synchronized to the grid at 0011 hours and reached a 640 megawatt output by 2100 hours. On January 19, 2010, a planned outage was taken on Unit 1 to install a spare transformer.
Unit 1 was synchronized to the grid on January 21, 2010 at 2326 hours and reached 100% power the next day at 1341 hours. VI. PREVIOUS SIMILAR EVENTS There have been no previous similar reportable events at CPNPP in the last three years. NRC FORM 366A (9-2007) PRINTED ON RECYCLED PAPER OAGI0001044_0000S}}