ML113140608

Submittal of Supplemental Information - Oconee for Regulatory Enforcement Conference

ML113140608
Person / Time
Site:	Oconee
Issue date:	11/02/2011
From:	Gillespie T Duke Energy Carolinas
To:	NRC/RGN-II
References
Download: ML113140608 (55)

Text

D k T. PRESTON GILLESPIE, JR.

u e Vice President 0Energy Oconee Nuclear Station Duke Energy 0N01 VP / 7800 Rochester Hwy.

Seneca, SC 29672 864-873-4478 864-873-4208 fax November 2, 2011 T. Gillespie@duke-energy. corn U.S. Nuclear Regulatory Commission

- Region H 245 Peachtree CenterAve., NE, Suite 1200 Atlanta, GA 30303-1257

Subject:

Oconee Nuclear Station Units 1, 2, and 3 Docket Nos.: 50-269, 50-270 and 50-287 Regulatory Enforcement Conference - Submittal of Supplemental Information Ref.:

Letter from Richard P. Croteau, Director NRC Division of Reactor Projects, to T. Preston Gillespie, Jr., Site Vice President, Duke Energy Carolinas, LLC, Oconee Nuclear Station

- NRC Inspection Report 050000269/2011018, 050000270/2011018, and 050000287/2011018, Preliminary Greater Than Green Findings, dated October 4, 2011.

As described in the aforementioned NRC enforcement conference choice letter, the Staff encourages Duke Energy Carolinas, LLC (Duke Energy) to submit any supporting documentation which would make the conference more efficient and effective, at least 14 days prior to the meeting date. In response to this statement, Duke Energy respectfully submits several supplemental documents which will be discussed at the November 16, 2011, enforcement conference. contains a document that is being requested to be withheld from public disclosure pursuant to 10 CFR 2.390 disclosure criteria. The affidavit supporting this request is given in.

If you have any questions or comments regarding this submittal, please contact Stephen C. Newman, Oconee Nuclear Station Regulatory Compliance Group, at 864-873-4388.

Sincerely, rrdIL4.esri T. Preston Gillespie, Jr.,

Vice President Oconee Nuclear Station Enclosures 1 through 5 contains company confidential information.

Withhold from public disclosure under 10 CFR 2.390.

Upon removal of this enclosure, the letter is uncontrolled.

www. duke-energy, corn

U. S. Nuclear Regulatory Commission November 2, 2011 Page 2 cc:

Mr. Victor McCree Administrator, Region II U.S. Nuclear Regulatory Commission Marquis One Tower 245 Peachtree Center Ave., NE, Suite 1200 Atlanta, GA 30303-1257 Mr. John Stang Project Manager U.S. Nuclear Regulatory Commission Office of Nuclear Reactor Regulation Washington, D.C. 20555 Mr. Andrew Sabisch NRC Senior Resident Inspector Oconee Nuclear Station Enclosure S contains company confidential information.

Withhold from public disclosure under 10 CFR 2.390.

Upon removal of this enclosure, the letter is uncontrolled.

Evaluation of Testing Performed on GE Spectra Breaker Model SELA36AIOIOO at High Temperature Conditions

Page lof 6 November 2, 2011 EVALUATION OF TESTING PERFORMED ON GE SPECTRA BREAKER MODEL SELA36AIO100 AT HIGH TEMPERATURE CONDITIONS Summary:

Testing of a GE Spectra breaker identical to those installed for 5SF pressurizer supplied heaters per Engineering Changes EC 106229, EC 106230 and 106231 has been performed to determine the response of the breakers in a non-steam environment when using a bounding 5SF temperature profile. The breaker successfully operated for a 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> duration (5SF mission time). An evaluation has been performed to determine if the testing was sufficient to prove the breakers could have operated as required while installed between June and August 2011.

Parameters that could affect the test outcome such as temperature, humidity, and pressure were reviewed to determine if the input parameters to the test were bounding. The temperature profile was increased by 17F from the design basis temperature model for the SSF events to account for:

1) The breaker being tested in an oven without being placed in a panelboard due to space limitations of the oven.

2) Instrument error To determine a differential temperature (dt) for item 1, initial testing of the these model breakers (70 amp plugs) was reviewed and a dT was determined between the panelboard and test chamber. This value was taken from a period of time when the breakers were energized but the chamber was at ambient temperature (no steam injected). This dT was determined to be 13F.

Based on instruments being used during the October test, the instrument error was assumed to be 4F.

After re-review for this evaluation, it was determined that more dT was experienced during July 2011 testing of these model breakers with a 100A plug installed. The initial review also did not include a correction for the size of test panelboard used in the June/July 2011 testing and the panelboards installed in the Oconee containments. Considering these factors, a dT of 26.4F (or 13.4F above that previously assumed) would be more bounding.

The 4F instrument uncertainty applied was based on the expected error during the October testing. The re-review determined that instrument uncertainty from the July testing that determined the dT could be applied in addition to the instrument uncertainty from the October test. This new instrument error is 8.6F (or 4.6F above that previously assumed).

Page 2of6 November 2, 2011 After applying a new conservative dT of 35F to temperature, the testing performed in October indicates that the breakers would be expected to operate for up to 45 hours5.208333e-4 days <br />0.0125 hours <br />7.440476e-5 weeks <br />1.71225e-5 months <br /> during the SSF event. The determination of that result is provided in the detailed information below.

During the re-review, it was determined that the design basis temperature profile used for the October test could have been lowered if actual containment temperatures during the June to August time period were used for the initial starting condition.

This condition was conservatively not used. In addition, NFPA-805 response temperature data was conservatively used even though this scenario does not currently apply to Oconee Nuclear Station until implementation of NFPA-805 is complete.

Additional Detailed Information:

The following information isto provide an evaluation of testing that was performed of a GE breaker model GE SELA36AIO100 in a heated test chamber. The testing was performed between 10/25/2011 and 10/28/2011. The breaker is the same model as the 5SF fed pressurizer heater branch feeder breakers installed in all three Oconee Units between June and August of 2011. The testing envelope used is provided as well as testing procedures (Attachments 1,2) and the basis for the criteria used for testing.

In evaluating the adequacy of the testing with regard to actual conditions, the following assumptions have been made:

1) The GE breakers are assumed to be insensitive to the pressures experienced during an 5SF event.

2) A current source was used without specific requirements for voltage. Since the trip criteria is based on current, it is assumed that voltage is inconsequential for this testing.

3) Humidity levels in containment are based on a lumped volume containment model. Humidity levels are not determined at discreet points in containment. Analysis of containment humidity during an SSF event indicates the bulk volume humidity will remain below 100%. This is assuming the expected loss of some RCS volume to the containment due to operation of the PORV and loss of the quench tank rupture disk during initial RCS pressurization of the 5SF event. This also assumes system leakages inside containment prior to the SSF event continue to add vapor to the containment air volume.

Due to the breakers being located outside the secondary shield wall and above the basement elevation of containment, the breakers are not near expected higher humidity areas (i.e. quench tank, etc.).

Therefore, relative humidity in the vicinity of the installed breakers is not expected to approach 100%.

4) The temperature profile provided in the test procedure is not bounding when worst case instrument uncertainty and expected panelboard temperature rise are included in the overall 5SF event temperature profile. An additional 17F was added to create the temperature profile, however, analysis performed below indicates an additional 3SF would be bounding rather than 17F. While the overall temperature profile was not bounding for a 72 hour8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> event, the results indicate that overall temperatures reached during testing are bounding for a shorter period of time than 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />. For example, modeling would indicate that a bounding temperature after 45 hours5.208333e-4 days <br />0.0125 hours <br />7.440476e-5 weeks <br />1.71225e-5 months <br /> for an SSF event is approximately 237F. During testing after 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />, a peak temperature of 273.5F was observed. This

Page 3 of 6 November 2, 2011 temperature when corrected for uncertainties, etc. would be approximately 237F. Since these temperatures are approximately equal, it is assumed the testing is bounding to prove operation of the breaker for approximately 45 hours5.208333e-4 days <br />0.0125 hours <br />7.440476e-5 weeks <br />1.71225e-5 months <br />.

Summary of OSC-5501 Containment Response Following a Loss of All AC Powerand Development of Design Basis Temperature Profile The design basis temperature profile was developed by taking the highest predicted temperature at a point in time from the following temperature response curves of OSC-5501 for the following scenario.

1) Appendix R Fire Event

2) Loss of All A.C. Power Event

3) NFPA-805 Event Documentation of the event analysis and further information are included as Attachment 4.

Test Procedure for Thermal Testing of Circuit Breakers provides the vendor test procedure for testing of the GE Spectra Breakers. contains pre-test pictures and Attachment 6 contains post-test pictures taken at the testing facility.

Basis for Testing Procedure Criteria and Inputs Breaker Type and Settings:

Tested Breaker: GE SELA36AIO100, 600V, 3Ph with SRPE100AO7O (70A) Plug. Breaker non-irradiated and plug irradiated.

Installed Breakers: Per ECs 106229, 106230, 106231, the installed breakers (branch feeder circuits) were GE SELA36AIO100 (70 amp plugs). These are branch breakers in the pressurizer heater circuit.

Tested breaker instantaneous trip setting is 5.

Installed breaker instantaneous trip setting is 6 based on ECs 106229 rev.0, 106230 rev. 0, 106231 rev.

0. The setting was then revised to mm per rev. 1 of the above modifications. These settings do not affect the ability of the breakers to perform their design basis function at elevated temperature.

Baseline/Post TOV Testing (prior to and after TOV Testing)

Current hold - This test ensures maximum current determined below can be maintained during the high temperature environment of a SSF scenario.

Instantaneous Trip Check - This test ensures breaker will trip per manufacturers specification.

Page 4 of 6 November 2, 2011 Insulation Resistance - This test assesses the adequacy of the insulation between poles of a circuit breaker and between each pole and ground. Acceptance per EPRI Molded Case Circuit Breaker Application and Maintenance Guide Section 9.1.

Contact Resistance - This test ensures adequate electrical quality of the connections and contacts in a circuit breaker. Reference EPRI Molded Case Circuit Breaker Application and Maintenance Guide Section 9.2.

Thermal Operability Verification (TOy) Testing Conditions:

Temperature/Pressure/Humidity Testing is performed by operating the breaker in a test environment where temperature is controlled to meet the profile described in the testing procedure. The breaker is cycled periodically to simulate changes in heater demand. The test profile is based on OSC-5501 Appendices B and C for SSF events. An additional differential temperature of 17F was added to the test profile acceptance criteria to provide margin. However, based on additional margin to account for instrument uncertainty and panel configuration, this evaluation determined that a f differential temperature will be applied. Details of the determination of the 35F differential temperature are included below.

1) Instrument uncertainty Instrument uncertainty for panel vs chamber differential temperature from June/July 2011 testing is determined below using the RSS with allowance for differences between installed and test panelboard surface area:

dT Instrument uncertainty= Inside Panelboard Uncertainty +Outside Panelboard Uncertainty Temperature Uncertainty for Reading is 1.8F for sensor and 1.8 for datalogger.

dT Instrument Uncertainty = (1.82 + 1.82)O.5

• 2 dT Instrument Uncertainty = 5.1F This dT is increased by 20% to account for panelboard size difference dT Instrument Uncertainty = 5.1F

• 1.2 =6.1 Instrument uncertainty is applied to the temperature measurement equipment as follows:

Instrument uncertainty for the October oven test = (1.82 + 1.82)0.5 = 2.5F Total Instrument uncertainty = 6.1F + 2.5F = 8.6F

2) Differential temperature across the breaker panel

Page 5 of 6 November 2, 2011 During initial testing in June/July 2011, temperatures were taken inside and outside of the test breaker box with the breakers closed and passing current and prior to heating of the chamber. This yielded a maximum differential temperature of 22 F. The test breaker box used is larger than the breaker box in the plant. This could affect heat transfer characteristics in a non-conservative manner (more heat transfer surface to dissipate heat from internal components).The test breaker box has dimensions of 43.5 x 20 x 5.81 (Source-photograph of breaker box model shows model AB43B.

Dimensions are from GE aftermarket catalog). The breaker box in the plant has dimensions of 34.25 x 22 x 5.75 (Source-CM 315-0019 001).

The differential temperature determined during the June/July 2011 testing is adjusted for the area variation based on the equation listed below:

Q= h A (DTtest)

DTtest adjusted= Atest/Aplant

• DTtest = 2,477.9 in3/ 2,153.9 in3

• DTtest= 1.15

• DTtest Round to 1.2

• DTtest DTtest will be increased by 20% to account for variation between area of test breaker box and area of breaker box in plant.

Q= heat generated by breaker-This variable is constant with regard to change in breaker box area.

A = Surface area of breaker box Aplant= Surface area of breaker box installed in plant-approximately 2,153.9 in2 2 *(3425fl

• 22) + 2 * (34.25* 5.75) + 2 * (22

• 5.75)= 2,153.9 inA2 Atest= Surface area of breaker box used in test-approximately 2,477.9 inA2 2 *(435I

• 20) + 2 * (43 5I* 5.81) + 2 * (20

• 5.81)= 2,477.9 in2 DTtest= differential temperature measured during test with no steam in test chamber.

DTtest adjusted= DTtest adjusted for area difference h= convection heat transfer coefficient-This variable is constant with regard to change in breaker box area.

Based on data from 7/7/2011 testing, differential temperature between the breaker box and the test chamber is approximately 22 F. Total temperature addition due to internal heating is therefore:

dT = 1,2

• 22SF = 26.4 F

dT + uncertainty = 26.4F + 8.6F = 35F

Page 6 of 6 November 2, 2011

3) Pressure and moisture/humidity Pressure and moisture/humidity are not controlled during the test. See assumptions at the beginning of the document.

Voltage/Amperage Amperage during the thermal testing was maintained at approximately 51 amps.

Reference Attachment 3.

Voltage during the testing was maintained at < 1 VAC. See assumptions.

Test Duration Temperature was ramped as shown in Attachment 2. This is based on the temperature profiles of OSC-5501 Appendix B. Test duration was 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.

The breaker was cycled open and closed per the test procedure requirements to simulate energizing and deenergizing of the heaters for RCS pressure control.

Test Results Testing was completed on 10/28/2011. Attachment 2 provides the temperature profile for the completed test. The breaker met all acceptance criteria for the thermal operability verification (Toy) test as well as pre-test and post-test verifications.

List of Attachments - Test Procedure for Thermal Testing of Circuit Breakers for Duke Oconee

- Test Results

- Determination of maximum current draw to a pressurizer heater panel feeder circuit

- Documentation of event and further information

- Pre-Test Pictures - Post-Test Pictures

I uawtpei.y

KIN ECTRICS KINECTRICS INC.

TEST PROCEDURE FOR THERMAL TESTING OF CIRCUIT BREAKERS FOR DUKE OCONEE October 19, 2011 Kinectrics Test Procedure: K-015963-PSWI-0006 ROl DUKE P0 00147492 Prepared by:

Stephen D, Bunny, P. Eng.

Sr. Project Manager Nuclear Parts and Qualification Kinectrics Inc Reviewed by:

Bob Mlnadeo Principal Engineer Nuclear Parts and Qualification Kinectrics US Inc Approved by:

Bert Grespan Manager.

Nuclear Parts and Qualification Kinectrics Inc

Date:

Date:

Date:

()+ °çzc.)1f OcI I 2c Client Approval By:

Date:

Page 2 of 12 Kinectrics US Inc.

K-01 5963-PSWI-0006-R01 REV ISSUE PREPARED BY REVIEWED BY APPROVED BY NO DATE 00 Oct 17, 2011 S. Burany B. Minadeo B. Grespan 01 Oct19, 2011 S. Burany B. Minadeo B. Grespan REVISION LOG

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K-015963-PSWI-0006-RO1 Page 3 of 12 REVISION HISTORY REVISION SECTION/

DESCRIPTION NUMBER PARAGRAPH 00 All Initial Issue Added: Instantaneous Trip setting to specimen

§1.1 description

§2.4 and Table 2.6.2 Instantaneous Setting corrected (setting 5 was 6) 01

§2.7 Clarified temperature tolerance on TOV profile Temperature at 0.3 hours3.472222e-5 days <br />8.333333e-4 hours <br />4.960317e-6 weeks <br />1.1415e-6 months <br /> revised to 191.1 °F (was Appendix A 190.0 °F)

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K-015963-PSWI-0006-RO1 Page 4 of 12 TABLE OF CONTENTS I

SCOPE 5

1.1 TEST SPECIMEN DESCRIPTION 5

1.2 APPLICABLE REFERENCES 5

2 TEST REQUIREMENTS 6

2.1 TEST SEQUENCE 6

2.2 SERVICE CONDITIONS 6

2.3 MARGINS 6

2.4 ACCEPTANCE CRITERIA 7

2.5 RECEIPT INSPECTION 7

2.6 BASELINE FUNCTIONAL TESTS 7

2.7 THERMAL OPERATIONAL VERIFICATION (TOV) TEST 9

2.8 POST-TOV FUNCTIONAL TESTING 9

2.9 SPECIMEN DISPOSITION FOLLOWING TEST COMPLETION 9

3 ACTION ON FAILURE 9

4 TEST EQUIPMENT 10 4.1 INSTRUMENT CALIBRATION 10 4.2 TESTINSTRUMENTLISTS 10 5

QUALITYASSURANCE 10 6

TEST REPORT 10 Appendix A

- Thermal Operational Verification Profile

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K-015963-PSWI-0006-R01 Page 5 of 12 I

SCOPE This test procedure specifies the requirements and process for performing Thermal Operability Verification (TOV) testing on a molded case circuit breaker. The TOV testing differs from the Duke postulated SSF event environment in that only the thermal parameter shall be simulated. Pressure and moisture/humidity will not be controlled during the test.

The breaker shall be removed from the panel (not mounted into a breaker panel) and Baseline Tested for Instantaneous trip function, Insulation Resistance, Current Hold, &

Contact Resistance. Following the baseline testing, the breaker is to be subjected to the TOV environmental test. This test program is to be performed in accordance with ISO 9001 requirements.

1.1 Test Specimen Description The test specimen consists of a molded case circuit breaker rated for 70 amps at 600VAC.

The breaker model number shall be recorded on the data sheets when the testing is performed.

An existing GE SELA36AIOI0O, 600V, 3Ph, circuit breaker with SRPE100A07O (70A) Rating Plug shall be tested. The condition of the breaker body is non-irradiated. The 70A plug has been exposed to 30,000 rad (gamma). An instantaneous trip setting of 5 shall be used throughout the test program.

As an option, this procedure may be used for alternative breaker models. Duke shall provide instantaneous trip test parameters and acceptance criteria. The make and model of the alternative breaker shall be recorded on a datasheet.

1.2 Applicable References 1.2.1 DUKE Purchase Order 00147492 1.2.2 Kinectrics ISO 9001 quality program

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K-01 5963-PSWI-0006-RO1 Page 6 of 12 2

TEST REQUIREMENTS 2.1 Test Sequence The test specimen shall be tested per the following test sequence.

Table 2.1: Test Program Sequence Test Sequence Receipt Inspection, Tagging, and Photographing Baseline Tests Current Hold 60A for 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> Instantaneous Trip Check Insulation Resistance @ 500 VDC (between poles and pole to ground with contacts closed and across open contacts)

Contact Resistance across closed contacts with IA current load Thermal Operability Verification (TOV) Test Ramp temperature (dry) from 157 °F to 269 °F with 51 A on breaker contacts Post-TOy Functional Tests Repeat baseline tests Post-Test inspection and Photographing 2.2 Service Conditions The only service conditions applicable to this test are the following:

Test Temperature:

269 °F Test Duration:

72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> Electrical Loading:

51 amps 2.3 Margins Margin has been added to the TOV curve (Appendix A) by Duke; no additional margin is required.

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K-015963-PSWI-0006-R01 Page 7 of 12 2.4 Acceptance Criteria This test program has the following applicable acceptance criteria:

Breaker must hold required current (51 A) throughout the TOV Test duration.

Breaker must not trip when loads are interrupted during the TOV test.

Breaker must demonstrate Insulation Resistance of 1.0 Meg-Ohm or greater at 500 VDC during functional testing Breaker must demonstrate Contact Resistance of 100 Milli-Ohms or less when carrying 1 amp load current (voltage drop method) during functional testing Breaker must hold 60 A for a duration of 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> during functional testing.

Breaker must demonstrate the instantaneous trip function during functional testing:

Breaker Plug Current I Time Requirements GE SELA36AIO1 00 SRPEI 00A070 280 Al No Trip 350 550 A Instantaneous (Instantaneous Setting 5) 70 A

<0.6 seconds

(<62 ms)

Acceptance criteria for alternative breakers shall be agreed upon with DUKE and document on the test datasheets 2.5 Receipt Inspection The test specimen shall be visually inspected and photographed to record any damage.

A tag shall be attached to the breaker indicating the project and ID number (K-01 5963- [manufacturer / model number]). The results of the receipt inspection and the test specimen descriptions shall be recorded on Kinectrics form QFIO-1 Record of Inspection of Incoming Items and shall correspond to the test specimen description in Section 1.1.

DUKE shall be informed if any obvious signs of physical damage are found. The test specimen will be photographed as received.

2.6 Baseline Functional Tests The baseline functional tests are required only to ensure that the breaker is functioning properly prior to the TOV test. The functional tests included within the scope of this program include:

2.6.1 Hold Current The breaker shall be subjected to a current of 60 A +/-3 A for 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />. The breaker shall not trip during the test. Record the average current and duration on a data sheet.

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K-015963-PSWI-0006-R01 Page 8 of 12 2.6.2 Instantaneous Trip Using a circuit breaker tester, the conditions listed in Table 2.6.2 shall be tested. Each phase shall be tested individually and repeated once for a total of eighteen (18) measurements. Any trip time results not meeting the Acceptance Criteria shall be reported to DUKE for disposition prior to performing the TOV Test. All data shall be recorded on data sheets for presentation in the final report.

Table 2.6.2 Instantaneous Trip Requirements Breaker Plug Current I Time Requirements GE SELA36AI0IOO SRPEI0OAO7O 280 A I No 350 550 A Instantaneous (Instantaneous Setting 5) 70 A Trip

<0.6 seconds

(<62 ms)

Acceptance criteria for alternative breakers shall be agreed upon with DUKE and document on the test datasheets 2.6.3 Insulation Resistance (IR)

Record breaker IR at 500 VDC at the following points using a Megger:

Across each set of open contacts Between each pair of Poles with the contacts Closed Record all IR data on a data sheet.

2.6.4 Contact Resistance (CR)

Record the CR of each breaker pole by applying a nominal current of 1.00 ampere (AC or DC) and measuring voltage drop. The numerical value of voltage drop in millivolts equals the numerical value of CR in milliohms. Record applied current and voltage drop, as well as the calculated CR on a data sheet.

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K-015963-PSWI-0006-R01 Page 9 of 12 2.7 Thermal Operational Verification (TOV) Test The breaker shall be placed into an environmental oven in the normal upright position.

Cable (4 AWG or larger) shall be attached to the LINE and LOAD interfaces of the breaker and the cables shall exit the thermal oven. The breaker shall be wired such that the poles are connected in series. A current of 51 amperes (+/-3 A) shall be used throughout the test.

The breaker current shall be continuously monitored and recorded to provide a breaker status (tripped or closed).

The oven shall be fitted with a calibrated thermocouple sensor to record chamber temperature within 3 inches of the specimen to provide a record of the environmental temperature. Pressure and relative humidity are uncontrolled.

The chamber heaters in the circulating air oven shall be used to increase temperature in accordance with the profile found in Appendix A. The chamber temperature shall be maintained above the profile described in Appendix A throughout the test.

In order to simulate the pressurizer heaters being switched OFF and ON, the current on the breaker branches shall be interrupted periodically during the Safe Shutdown Facility (SSF)

Event test. Each interruption shall be 10 minutes in duration. The interruptions will take place at approximately 30 minutes, 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br />, 4 hours4.62963e-5 days <br />0.00111 hours <br />6.613757e-6 weeks <br />1.522e-6 months <br />, 24 hours2.777778e-4 days <br />0.00667 hours <br />3.968254e-5 weeks <br />9.132e-6 months <br />, 48 hours5.555556e-4 days <br />0.0133 hours <br />7.936508e-5 weeks <br />1.8264e-5 months <br /> and 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> into the test. The interruptions shall be simulated by disabling and then enabling the current.

The results of this test shall be recorded on a data sheet for presentation in the final report.

2.8 Post-TOV Functional Testing Section 2.6 of this procedure shall be repeated in its entirely.

2.9 Specimen Disposition Following Test Completion The test specimen shall be shipped back to DUKE Oconee FOB Kinectrics/Toronto.

DUKE shall be responsible for shipment costs and arrangements for the return of the specimens.

3 ACTION ON FAILURE Any anomalies may occur that will be documented as required by Kinectrics ISO 9001 QA Program. Anomalies may include specimen or procedure issues or occurrences not expected in the course of the testing process. DUKE shall provide resolution or concurrence for all anomalies and non-conformances.

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K-015963-PSWI-0006-R01 Page 10 of 12 4

TEST EQUIPMENT 4.1 Instrument Calibration Prior to being used in this test program, all measuring and test equipment shall be calibrated in accordance with Kinectrics quality program. Calibration equipment and standards used in performing all calibrations shall be traceable to National or International measurement bodies (e.g. National Research Council Canada (NRCC) or National Institute of Standards and Technology (NIST)). Calibration certificates shall be made available to the client on request.

4.2 Test Instrument Lists All instrumentation, measuring and test equipment used in the test program shall be recorded on Kinectrics form QFI 1.1 Instrumentation Sheet with calibration dates and accuracies.

5 QUALITY ASSURANCE The test program shall be performed and all reports shall be prepared in accordance with Kinectrics QA Program which complies with the requirements of ISO 9001. Forms for this work will be prepared according to Kinectrics QA requirements and used to record all data and will be signed off appropriately.

6 TEST REPORT The test report will meet the following requirements:

Title page with signatures and dates Name and address of test facility Statement of test objectives Identification, Description and Quantity of Test Specimens Test Set-Ups and Interfaces Photograph(s) showing samples Test Procedure List of all measuring equipment used including calibration dates Test data and results Conclusions References Anomalies Description and Disposition if required

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K-015963-PSWI-0006-RO1 Page 11 of 12 Appendix A

Thermal Operational Verification Profile

Spectra Breaker Test Profile 280.0 270.0 260.0 250.0 2 ao.o U 230.0 2200 210.0 200.0 igo.o 180..a 170.0 160.0 150.0 Time [Hrs]

Temperature 1°F]

Temperature 1°C]

0.0 157.0 69.4 r_

0.3 191.1 88.4 7

9__

7

50 2148 1015

--1 7.0 221.0 105.0

/

10.0 226.1 107.9 CD C)

C)

C)

C Cl) 2 C)-

CD 0)

C)

-a CI) b00 0) 0 0

Co CD F) 0 F) 20.0 15.0 232.1 111.1 0

236.8 29.0 28.0 244.0 117,8 113.8 54.0 243.0 117.2 260.0 126.7 72.0 269.0 131.7 5

10 15 20 25 30 35 40 45 50 55 50 55 70 75 80 Time [hours}

290

K-015963 - Duke Oven Test - GE Breaker 1w 70A Plug 70 270 250 U.

230 210 190 170 65 60 U

=

t 1

I.

50 45 40 150 0

10 20 30 40 50 60 70 Time [Hrs]

Page 1 of 5 Project K-015963 - Duke Breaker Datasheet K-015963-DATA-OOlO ROG Reference Procedure: K-O15963PSWl-OOO6 R O t Circle One:

ç.Base Functional Tests (Section2 L_)

Post-TOV Functional Tests (Section 2.8) 2.6.2 - Instantaneous Trip - Record actual current and time; poles to be individually tested; record two sequential test results per pole Plug Rating:

Irradiated ivi Non - Irradiated Set and Verify Instantaneous (Setting 5 for GE 70A Plug)

Specimen Test Requfrernents and Results (for GE SE136AlO1OO 1w SRPE100AO7O plug)

Pole#

280 A I No Trip

( 3 seconds)

K-O159638REAKER-LCA))

350 550 A

<0.6 seconds Pt#1 Irradiated Non

= Irradiated Li 850 A I Instantaneous

(<62 ms)

Result 3A =3o*r Ao I

1=

(.4 Pt#2

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Project K-015963 - Duke Breaker Page 2 of S Datasheet: K-015963-DATA-OO1O ROO Section 2.6.1 Hold Current The breaker shall hold 60 A +3 A for a period of no less than 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> Record Average Current:

2. A Record Total Duration (target 60 minutes, 0, +5 minutes):

G 2 M Results (circle one):

I s)

Fail

Project KO15963

- Duke Breaker Datasheet: K-015963-DATA-OO1O ROO Page 3 of 5 SectIon 2.6.3 - Insulation Resistance (IR)

Using a Megger at 500Vdc for 1 minute, measure IR at the following points:

[

Across Open Contacts

}

Results Reuirement)

Pass / Fail f

Li

- Line to Load PA S S

12 Line to Load

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> I MC)

PA S S L3 Line to Load PA S S Pole-to-Pole with Contacts Results Requirement Pass! Fail Closed LltoL2 L2toL3 j

>1MC)

Li to 13

]

2

Page 4 of 5 Project K.-015963

- Duke Breaker Datasheet: K-015963-DATA0010 ROD Section 2.6.4 Contact Resistance (CR)

Record the CR of each breaker pole by applying a current of 1.00 ampere (AC or DC) and measuring the voltage drop across the contact Actual Current Measured Voltage Voltaae Pole Resistance RequIrement Pass I Fad (Target 1.00 A)

Drop Across Contacts Current 11

.QQA 0

Pss 12

<lOOmO PA55 13 0c2/k

Project K-015963

- Duke Breaker Page 5 of 5 Datasheet: K-015963-DATA-OO1O ROO Notes:

Completed By:

Date:

Reviewed I Approved By:

Date:

2 (1

Page 1 of 5 TOV Function&Teecn 2.6.2 - Instantaneous Trip - Record actual current and time; poles to be individually tested; record two sequential test results per pole Project K-015963

- Duke Breaker Datasheet: K-015963-DATA-OO1O ROO Reference Procedure: K-015963-PSWI-0006 R C.)

Circle One:

Baseline Functional Tests (Section 2.6)

Test Requirements and Results Set and Verify (for GE SELA36AIO100 1w SRPE100AO7O plug)

Specimen Instantaneous 280 A r

850 A i Result (Setting 5 for GE Pole #

I No Trip 350 550 A Iiistantaneous 70A Plug)

(3 seconds)

< 06 seconds

(<62 ms) 5( IA c.02c3 26l4D iOs t#i j

A-Li I

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A Pt #2 FA S S Irradiated

Non - Irradiated

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Project K-015963 Duke Breaker Page 2 of 5 Datasheet: K-015963-DATA-0010 R00 Section 2.6.1 Hold Current The breaker shall hold 60 A +/-3 A for a period of no less than 1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> Record Average Current:

G A Record Total Duration (target 60 minutes, -0, ÷5 minutes):

Results (circle one):

(

Pass Fail

Project K-015963

- Duke Breaker Datasheet: K-015963-DATA-OO1O ROD Page 3 of 5 Section 2.6.3 - Insulation Resistance (1K)

Using a Megger at 500Vdc for 1 minute, measure IR at the following points:

Across Open Contacts Results Requirement Pass / Fail LI

- Line to Load 7 SOc.

P\\ SS L2-LinetoLoad

>1MQ L3-LinetoLoad PoIeto-PoIe with Contacts Results Requirement Pass / Fail Closed Li to L2 S S L2toL3

> SOQCSU

>1MO LitoL3

>5coG

Project K-015963 Duke Breaker Page 4 of 5 Datasheet: K-015963-DATA-O010 R0O Section 2.6.4 Contact Resistance (CR)

Record the CR of each breaker pole by applying a current of 1.00 ampere (AC or DC) and measuring the voltage drop across the contact Actual Current Measured Voltage Resistance=

VoltaRe RequIrement Pass / Fall 0 e (Target 1.00 A)

Drop Across Contacts Current ii

• Oo A 0.

s_i

,QQA 0 3?J

<lOOmC) 13 O4fr(L-

Project K-015963

- Duke Breaker Datasheet: K-015963-DATA-OO1O ROO PageS of 5 Completed By:

Reviewed / Approved By:

Date:

Cc-t 2t(Z}LI Notes:

Date:

ci-3,2((

E uawqe

Calculation No.:

OSC -5093 ICC No.:

13d Page:

1 Calculation

Title:

U1/2/3, SSF AC Power System Voltage and Short Circuit Analysis Part A (completed by ICC Preparer)

Change No. (e.g., EC, PIP): P[P 0-11-6700 lnnage!Outage:

N/A Title SSF pressurizer panelboards inside containment could potentially trip on high ambient temperature DESCRIPTION OF POWER SYSTEM CHANGES In the space below, provide details or the changes related to the power system including specific electrical equipment involved.

Atlach additional pages and supporting documentation as needed.

As a result of high ambient conditions during an 5SF event, the 5SF pressurizer panel boards inside containment could trip. A bounding Pzr Heater current draw is required to evaluate this potential trip situation.

Prepared by (type name):

Aldean Benge Station:

GO Date: 6/03/2011 Identify charging codes related to the change - either Operating Unit & Process OR Operating Unit & Project/Activity.

Operating Unit:______ Process:

OR Operating Unit::______ Project/Activity:___________

Phone No.:

980-373-3866 Date Response is Needed (mm. 30 days ahead): 6/03/20 11 Send to: Joe E. Stout, (980) 373-3865 Part B (completed by NGD-PSA)

DESCRIPTION OF THE CHANGE TO THE CALCULATION Describe all calculation changes needed, including changes to design inputs and references.

OSC -5093 does not evaluate maximum current draw to loads. The calculation verifies adequate voltage at load terminals during a 3 unit 5SF event. A new analysis determining the maximum current draw to a pressurizer heater panel feeder circuit would be required. A bounding analysis is presented below:

Assumptions 1.

The voltage drop between the source and the pressurizer heater with the highest voltage is zero. For an 5SF event involving only one unit, with a limited number of loads operating, the drop between the source and the worst case heater would be small. Assuming a value of zero Is conservative.

2.

All 3 heater elements In the pressurizer heater panelboard feeder circuit are considered operating.

References 1.

AP/0/A/1700/025, Rev. 050, Standby Shutdown Facility Emergency Operating Procedure 2.

IP/0/B/0200/037, Rev. 074, Pressurizer Heater Test And Surveillance 3.

OEE 0149-12, Rev. 002, Elementary Diagram 5SF Press. Htr. Group C, Bank 2 A pressunzer heater panel feeder circuit supplies 3 heaters connected in a delta arrangement (Ref. 3). The minimum heater resistance that will be returned to service following testing is 22.25 ohms (Ref. 2, Enclosure 11.2.1, page 1).

The D/G may operate at up to 4500 V for 2 hours2.314815e-5 days <br />5.555556e-4 hours <br />3.306878e-6 weeks <br />7.61e-7 months <br /> (Ref. 1, Section 4.20). See also assumption 7.6 of the calculation for D/G operating voltage (4500V, 1.0817 pu). Based on the above information, the maximum current draw on a pressurizer heater panel feeder circuit supplying 3 heaters connected in a delta arrangement would be:

(line current seen by panel breaker) = 30.5

• Vline to line/Z V = 4500/4160

• 600 = 649.0385 V

= 3°

• 649.0385/22.25 = 50.52 Amps DESCRIPTION OF THE IMPACT ON THE CALCULATION Explain why this change is Insignificant. Include additional pages If needed.

The change will require the above analysis be added to the calculation. This is a small change in scope for the calculation.

Additional Reviews that may be required: None

06/03/2011 19:43 7049216839 DOOM & CDLA1tWtI

PAGE 91 Calculation No,:

OSC -5093 ICC No.:

13d Page:

2 Calculation

Title:

1.11/2/3, SSF AC Power System Voltage and Short Circuit Analysis This interim change has been reviewed for the oumulatfre effects of this and other Intetim changes to date.

J The engineerIng change is not significant, so the calculation does not need to be revised before this engineering change Is installed.

Although thIs engineering change Is acceptable, have sufficient changes accumulated such that it may be cumbersome to determine the significance of any future changes?

DNo IS] Yes A luture celculalon revision will be scheduled outside of the engineedng change schedule.

NGD-PSA Task No. for this revision:

09-095 Current number of ICCs for this calculation (Including this one):

7 Prepared by:

Aidean uenge c

41%.. 5

--n

Date, 6/03f20i1 Checked by:

ti /

Date:

6737-If Verification Method:

WMethod 1 C Method 2 C] Method 3 I] Other Approved by:

t 2

r&. ?464 Date

/3/Zc //

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The following was provided by Duke Safety Analysis:

The temperature profile used for testing the GE Spectra breakers is a composite from the results of the following events analyzed in OSC-5501: Loss of all A.C. power, Appendix R fire, and NFPA-805 fire.

Description of Analyses The purpose of the three analyses used to develop the testing temperature curve is to generate conservative containment temperature profiles for the three events. While the containment pressure response is examined, containment pressure remains well below the containment design limit.

Therefore, assumptions for initial conditions and boundary conditions are made in order to maximize the containment temperature for each event.

Initial Conditions and Boundary Conditions Temperature:

For all three events, the initial temperature is set to 140 °F. This assumption conservatively bounds indicated peak containment temperatures and maximizes the temperature response for the analysis.

Pressure:

Oconee Technical Specification 3.6.4 limits the maximum containment pressure during normal operation to 1.2 psig. Sensitivity studies indicate that temperature results are insensitive to an initial pressure band of 0.0-1.2 psig. Therefore, the initial pressure is not a significant parameter. For the loss of all A.C.

power event, an initial pressure of 1.2 psig is used. An initial pressure of 0.0 psig is used for the Appendix R and NFPA-805 Fire events.

Humidity:

Since the purpose of the analyses is to maximize containment temperature and any release from the RCS to containment immediately flashes to saturation conditions, initial humidity is maximized and set to 100%.

Heat Source:

For all three events, the primary heat source in the analyses is ambient losses from the RCS to the containment environment. The RCS ambient heat loss used in the analyses is based on recent test data for RCS at full power conditions, and is increased to account for measurement and analytical uncertainties.

Containment Free Volume:

The containment free volume is reduced by 2% for all three analyzed events.

Containment Cooling:

No systems are credited for actively cooling containment. The only cooling mechanism is heat transfer to the surrounding structures in containment.

RCS Release:

For the loss of all A.C power event, it is assumed that there is no cooldown of the RCS and no release from the primary system to containment. This assumption maximizes the ambient heat loss from the RCS to containment by maintaining the RCS at post-trip temperature. Any release from the RCS will immediately flash to the saturation temperature of the vapor partial pressure in containment. Given the magnitude of anticipated (potential) RCS releases during the loss of all A.C. power event, the vapor partial pressure will remain relatively low and the saturation temperature for the flashing steam will be less than the air temperature, which causes a cooling effect. Therefore, assuming no releases from the RCS maximizes temperature by minimizing the amount of superheat removed from the containment environment from the introduction of saturated steam.

For the Appendix R fire event, a cooldown of the RCS is assumed to begin 28 hours3.240741e-4 days <br />0.00778 hours <br />4.62963e-5 weeks <br />1.0654e-5 months <br /> after event initiation.

RCS releases to containment associated with the cooldown are credited.

The NFPA-805 fire analysis assumes there is no cooldown of the RCS during the 72-hour period. Releases from the RCS to containment from the intermittent opening of the reactor head vent are credited during the event.

Analysis Results For the loss of all A.C. power event, the ambient heat addition from the RCS causes the building atmosphere to superheat (T,team > Tsat). The rate of temperature increase slows down as heat transfer to the passive structures in containment increase due to the increasing tVr between the air and the structures. The temperature inside containment reaches 249F after 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br />.

The containment temperature response for the Appendix R fire event is very similar to that of the loss of all A.C. power analysis for the first 28 hours3.240741e-4 days <br />0.00778 hours <br />4.62963e-5 weeks <br />1.0654e-5 months <br /> of the event. At 28 hours3.240741e-4 days <br />0.00778 hours <br />4.62963e-5 weeks <br />1.0654e-5 months <br />, the containment temperature has increased to 226F. Twenty-eight hours after event initiation, RCS cooldown and associated releases to the containment environment from the RCS are assumed to begin. Once the RCS releases begin, containment temperature decreases due the removal of superheat from the building atmosphere as the released RCS inventory flashes to steam. The temperature reduction ceases once the containment temperature reaches the saturation temperature of the vapor partial pressure, which is increasing due to steaming of the RCS.

Containment temperature peaks around 237DF for the Appendix R fire event analysis and then begins to decrease. The peak temperature occurs just as the energy conduction rate into the passive structures in containment matches the energy addition rate from RCS ambient heat loss and releases from the primary system. The final temperature inside containment at 72 hours8.333333e-4 days <br />0.02 hours <br />1.190476e-4 weeks <br />2.7396e-5 months <br /> is 231F.

For the NFPA-805 fire event analysis, the temperature steadily increases to about 252°F over the 72-hour period. During the periodic steaming of the RCS to containment, the temperature momentarily decreases as the Reactor Building atmosphere returns to saturated conditions. When the steaming ceases, the containment atmosphere tends to become slightly superheated.

5SF Breaker Testing Temperature Curve The temperature curve used during the SSF breaker testing is based on a composite curve of the three analyses previously described, where the temperature at any point in time is the maximum of the results from the three events. As previously mentioned in this report, additional margin is added to the composite curve in developing the temperature profile used for the breaker testing.

Consideration of Relative Humidity on Pressurizer Heater Breaker Testing A containment analysis has been performed that uses more realistic initial conditions for the containment atmosphere and includes contributions from RCS leakage and potential releases from the pressurizer following reactor trip. The results from this analysis indicate that potential releases of RCS inventory to the containment environment attributed to pressure relief through the pressurizer code safeties early in the event would not lead to an entirely saturated containment environment (100%

relative humidity). Continuous leakage to the sump over the 72-hour period would not be sufficient to raise the humidity of the atmosphere as temperature rises due to ambient losses from the RCS.

Therefore, provided that significant distance and obstruction exist between the pressurizer heater breaker box and the quench tank (possible RCS release path early in the event), it is expected that the relative humidity in the vicinity of the pressurizer heater breaker box would not reach saturation during an event in which no further releases from the RCS are credited.

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Significance Determination Process Evaluation for Oconee SSF Pressurizer Heater Breaker Unavailability