ML13018A100

Drift Study for Abb Model ITE-27H Undervoltage Relays

ML13018A100
Person / Time
Site:	River Bend
Issue date:	01/20/2009
From:	Hunter R Entergy Operations
To:	Wang A Plant Licensing Branch IV
Wang A
Shared Package
ML13018A081	List: ML13018A084 ML13018A100 ML13018A103 ML13018A107 ML13018A110
References
TAC ME7767 G13.18.6.3-006
Download: ML13018A100 (41)

Text

ANO-1 ANO-2 GGNS IP-2 IP-3 PLP JAF PNPS RBS VY W3 (1) (2)

CALCULATION EC # 11753 Page 1 of 41 COVER PAGE (3) Design Basis Calc. YES NO (4) CALCULATION EC Markup (5 ) (6)

Calculation No: G13.18.6.3-006 Revision: 0 (7)

Title:

Drift Study for ABB Model ITE-27H Undervoltage Relays (8) (9)

System(s): 508 Review Org (Department): NSBE3 (I&C Design)

(10) (11)

Safety Class: Component/Equipment/Structure Type/Number:

Safety / Quality Related ENS-SWG1A-27-1A ENS-SWG1A-27-1B Augmented Quality Program Non-Safety Related ENS-SWG1A-27-1C ENS-SWG1B-27-1A ENS-SWG1B-27-1B ENS-SWG1B-27-1C (12)

Document Type: F43.02 (13)

Keywords (Description / Topical G G G G G G G G G G G G G G G G G G G G Codes): Drift G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G G REVIEWS (14) (15) (16)

Name/Signature/Date Name/Signature/Date Name/Signature/Date R.A. Hunter / _R.J. Hannigan /

/1-20-09 See AS for electronic signature

/ 1-20-09 Responsible Engineer Design Verifier Supervisor/Approval Reviewer Comments Attached Comments Attached

DRIFT ANALYSIS G13.18.6.3-006 ENGINEERING DEPARTMENT Revision 0 RIVER BEND STATION PAGE 2 OF 14 CALCULATION CALCULATION NO: G13.18.6.3-006 REFERENCE SHEET REVISION: 0 I. EC Markups Incorporated None II. Relationships: Sht Rev Input Output Impact Tracking Doc Doc Y/N No.

1. 350578 NA  ! " N

2. 350601 NA  ! " N

3. 350720 NA  ! " N

4. 350863 NA  ! " N

5. 350864 NA  ! " N

6. 351061 NA  ! " N

7. 351062 NA  ! " N

8. 351119 NA  ! " N

9. 362704 NA  ! " N

10. 362705 NA  ! " N

11. 362707 NA  ! " N

12. 362708 NA  ! " N

13. 368038 NA  ! " N

14. 368039 NA  ! " N

15. 368040 NA  ! " N

16. 368041 NA  ! " N

17. ECH-NE-08-00015 000  ! " N

18. G13.18.6.1-ENS-002 0 000 "  ! Y 11753

19. STP-508-1600 1 16  ! " N

20. STP-508-1600 1 16A  ! " N

21. STP-508-1600 1 17  ! " N

22. STP-508-1600 1 18  ! " N

23. STP-508-1600 2 16  ! " N

24. STP-508-1600 2 16A  ! " N

25. STP-508-1600 2 17  ! " N

26. STP-508-1600 2 18  ! " N

27. STP-508-1600 3 18  ! " N

28. STP-508-1600 4 18  ! " N

29. STP-508-1600 5 18  ! " N

30. STP-508-1600 6 18  ! " N

31. STP-508-1600 7 18  ! " N

32. STP-508-1600 8 18  ! " N

33. STP-508-1600 9 18  ! " N

34. STP-508-1600 10 18  ! " N

35. STP-508-1600 11 18  ! " N

36. STP-508-1600 12 18  ! " N

DRIFT ANALYSIS G13.18.6.3-006 ENGINEERING DEPARTMENT Revision 0 RIVER BEND STATION PAGE 3 OF 14 CALCULATION CALCULATION NO: G13.18.6.3-006 REFERENCE SHEET REVISION: 0 II. Relationships (contd): Sht Rev Input Output Impact Tracking Doc Doc Y/N No.

37. STP-508-1600 13 18  ! " N

38. STP-508-1600 14 18  ! " N

39. STP-508-1600 15 18  ! " N

40. STP-508-1600 16 18  ! " N

41. STP-508-1600 17 18  ! " N

42. STP-508-1600 18 18  ! " N

43. STP-508-1600 19 18  ! " N

44. STP-508-1600 20 18  ! " N

45. STP-508-1600 21 18  ! " N

46. STP-508-1600 22 18  ! " N

47. WO-50688087 0  ! " N

48. WO-50688088 0  ! " N

49. WO-50688091 0  ! " N

50. WO-50688092 0  ! " N

51. WO-50688089 0  ! " N

52. WO-50688090 0  ! " N

53. WO-50688085 0  ! " N

54. WO-50688086 0  ! " N

55. WO-50989677 0  ! " N

56. WO-50989678 0  ! " N

57. WO-50990339 0  ! " N

58. WO-50990340 0  ! " N

59. WO-50990919 0  ! " N

60. WO-50990920 0  ! " N

61. WO-50991471 0  ! " N

62. WO-50991472 0  ! " N

63. WO-51034041 0  ! " N

64. WO-51035362 0  ! " N

DRIFT ANALYSIS G13.18.6.3-006 ENGINEERING DEPARTMENT Revision 0 RIVER BEND STATION PAGE 4 OF 14 CALCULATION CALCULATION NO: G13.18.6.3-006 REFERENCE SHEET REVISION: 0 III. CROSS

REFERENCES:

1. American National Standard N15.15-1974, Assessment of the Assumption of Normality (Employing Individual Observed Values)

2. ANSI/ISA-S67.04-Part I-2000, Setpoints for Nuclear Safety Related Instrumentation

3. DOE Research and Development Report No. WAPD-TM-1292, Statistics for Nuclear Engineers and Scientists Part 1: Basic Statistical Inference, February 1981

4. EPRI TR-103335R1, Statistical Analysis of Instrument Calibration Data; Guidelines for Instrument Calibration Extension / Reduction Programs, October 1998

5. ISA-RP67.04-Part II-2000, Methodologies for the Determination of Setpoints for Nuclear Safety-Related Instrumentation, Second Printing, June 12, 1995

6. NRC Generic Letter 91-04, Changes in Technical Specification Surveillance Requirements to Accommodate a 24 Month Fuel Cycle, April 2, 1991 IV. SOFTWARE USED:

Title:

N/A Version/Release: Disk/CD No.

V. DISK/CDS INCLUDED:

Title:

N/A Version/Release Disk/CD No.

VI. OTHER CHANGES:

DRIFT ANALYSIS G13.18.6.3-006 ENGINEERING DEPARTMENT Revision 0 RIVER BEND STATION PAGE 5 OF 14 Revision Record of Revision Initial issue.

0

DRIFT ANALYSIS G13.18.6.3-006 ENGINEERING DEPARTMENT Revision 0 RIVER BEND STATION PAGE 6 OF 14 TABLE OF CONTENTS 1! Purpose!.................................................................................................................................................!7!

2! Conclusions!...........................................................................................................................................!8!

3! Design!Inputs!.........................................................................................................................................!8!

4! References!.............................................................................................................................................!8!

5! Assumptions!..........................................................................................................................................!9!

6! Method!of!Analysis................................................................................................................................!9!

7! Analysis!................................................................................................................................................!10!

8! Attachments!........................................................................................................................................!14!

! Attachment 1 - Drift Analysis Supporting Information (Excel Spreadsheet) - 19 pages Attachment 2 - DVR Forms with comments - 8 pages

DRIFT ANALYSIS G13.18.6.3-006 ENGINEERING DEPARTMENT Revision 0 RIVER BEND STATION PAGE 7 OF 14 1 Purpose 1.1 The purpose of this analysis is to establish more realistic drift values and characteristics to be used by instrument uncertainty calculations for determination of setpoints and allowable values for the subject instrumentation. The drift values are determined by historical As Found / As Left data analysis.

1.2 Specifically, this analysis addresses ASEA Brown Boveri (ABB) Model ITE-27H Undervoltage (UV) Relays with tag numbers as shown in Table 1.2-1 below. Also shown in the table are the calibration procedure numbers, device functions, and applicable Technical Specification (TS) sections. The results of this analysis can be conservatively applied to any ABB Model ITE-27H Undervoltage Relay used at River Bend Station that meets the criteria listed in Section 3.5.3 of Reference 4.1.3, Considerations When Combining Instruments Into a Single Group.

TABLE 1.2-1 COMPONENT LIST PROCEDURE NO. TAG NO. FUNCTION TS SECTION ENS-SWG1A-27-1A Loss of Power (LOP) Instrumentation ENS-SWG1A-27-1B STP-508-1600 ENS-SWG1A-27-1C Divisions 1 and 2 4.16kV Emergency Bus 3.3.8.1.3-1.a STP-508-1601 ENS-SWG1B-27-1A Undervoltage ENS-SWG1B-27-1B ENS-SWG1B-27-1C Loss of Voltage - 4.16 kV basis

DRIFT ANALYSIS G13.18.6.3-006 ENGINEERING DEPARTMENT Revision 0 RIVER BEND STATION PAGE 8 OF 14 2 Conclusions 2.1 The bounding Analyzed Drift (DA) for the ABB Model ITE-27H Undervoltage Relays (See Table 1.2-1) has been determined to be ! 0.392 VAC for 30 months (24 months +

25%), with no significant bias. The Analyzed Drift should be treated as a normally distributed, 2" value for uncertainty analysis.

2.2 The results of this analysis can be conservatively applied to all of the Undervoltage relays in Table 1.2-1 and to any ABB Model ITE-27H Undervoltage Relay used at River Bend Station, which meets the criteria listed in Section 3.5.3 of Reference 4.1.3, Considerations When Combining Instruments Into a Single Group.

3 Design Inputs 3.1 Pages 1 through 3 of Attachment 1 provide a listing of the historical As Left (AL) and As Found (AF) data, as obtained from Reference 4.2.1, with any data exclusions or modifications noted. All dates of calibration are also entered to provide time intervals between calibrations.

4 References 4.1 METHODOLOGY 4.1.1 ANSI/ISA-S67.04-Part I-2000, Setpoints for Nuclear Safety Related Instrumentation 4.1.2 ISA-RP67.04-Part II-2000, "Methodologies for the Determination of Setpoints for Nuclear Safety-Related Instrumentation," Second Printing, June 12, 1995 4.1.3 ECH-NE-08-00015, Instrument Drift Analysis Design Guide," Rev. 0, Generated by EXCEL Services Corporation, July 2008 4.1.4 EPRI TR-103335R1, "Statistical Analysis of Instrument Calibration Data; Guidelines for Instrument Calibration Extension / Reduction Programs," October, 1998 4.1.5 DOE Research and Development Report No. WAPD-TM-1292, "Statistics for Nuclear Engineers and Scientists Part 1: Basic Statistical Inference," February 1981 4.1.6 NRC Generic Letter 91-04, "Changes in Technical Specification Surveillance Requirements to Accommodate a 24 Month Fuel Cycle," April 2, 1991 4.1.7 American National Standard N15.15-1974, "Assessment of the Assumption of Normality (Employing Individual Observed Values)"

4.2 PROCEDURES 4.2.1 Historical Calibration Records from RBS Surveillance Test Procedure Results for STP-508-1600, 1601 4.3 MISCELLANEOUS REFERENCES 4.3.1 None

DRIFT ANALYSIS G13.18.6.3-006 ENGINEERING DEPARTMENT Revision 0 RIVER BEND STATION PAGE 9 OF 14 5 Assumptions 5.1 This drift report employs those assumptions customarily used for standard statistical analyses, as directed by Reference 4.1.3, such as the assumption that a distribution is normal and the use of statistical tests to confirm this hypothesis.

5.2 This drift report is based on analysis of historical As Found and As Left data from calibration records for the devices listed in Table 1.2-1. The results of this analysis can also apply to any ABB Model ITE-27H Undervoltage Relay used at RBS, but care must be taken when applying these results. Specifically, in order to apply the results of this analysis to other similar devices, the devices must meet the criteria listed in Section 3.5.3 of Reference 4.1.3, Considerations When Combining Instruments Into a Single Group.

6 Method of Analysis 6.1 The methodology used for this analysis is Reference 4.1.3, which is written in accordance with Reference 4.1.4, using References 4.1.1, 4.1.2 and 4.1.7 to supplement. An overview of the methodology is given herein, and any deviation from Reference 4.1.3 or any supplemental methods used herein are described.

6.2 This analysis determines the drift values for the subject instrumentation by analysis of historical As Found / As Left data from calibration records. Drift for a given device for a calibration period is determined by subtracting the previous As Left setting from a more recent As Found setting. The time interval for that calibration period is determined by subtracting the previous date from the more recent date, in units of days. All retrievable As Left and As Found data is collected for each calibration performed on each device covered by this report, for the study period. From this information, the drift and calibration interval is generated for each possible instance. Per Section 3.4.2 of Reference 4.1.3, "The goal is to collect enough data for the instrument or group to make a statistically valid pool." The devices covered by this report are currently calibrated on an 18 Month basis, and the proposed extension is for a 24 Month nominal calibration interval. Therefore, a study period of 10 years represents more than six of the present calibration cycles, and five of the proposed calibration cycles, which is adequate to understand the component's performance over time. Also, a sufficient number of valid drift values are provided as a result of the selected study period to make a statistically valid pool. Therefore, As Found and As Left Data values are entered from calibrations occurring for approximately the last 10 years.

6.3 Determination of the Analyzed Drift is generally accomplished through the following steps.

6.3.1 Gather and Generate Raw Drift Data: In addition to gathering the As Found and As Left data, and computing the drift values and time intervals, this step also involves an investigation into whether all of the devices should be analyzed together, or whether they should be separated into smaller analysis groups. Additionally, this step involves careful screening of the input data for errors or other situations that would not allow proper determination of drift.

6.3.2 Determination of Outliers and Statistical Summary: In order to properly model the drift characteristics for a device, it could be proper to remove up to one more data value, which obviously does not conform to the vast majority of the data. A t-Test is

DRIFT ANALYSIS G13.18.6.3-006 ENGINEERING DEPARTMENT Revision 0 RIVER BEND STATION PAGE 10 OF 14 performed on the data to detect any outliers, and remove up to one if appropriate, per the guidelines of Reference 4.1.3. Additionally, the basic statistical values which describe the group of drift data are derived in this step, including such parameters as Mean, Standard Deviation, Count, Median, Minimum, Maximum, etc.

6.3.3 Tests for Normality: Per Reference 4.1.3, a statistical test (W or D-Prime, depending on sample size) is performed on the drift data to support the hypothesis that the data conforms to a normal distribution. If this test is unable to support that hypothesis, then a Coverage Analysis is performed to ensure that the data can be conservatively modeled by a normal distribution and to provide an adjustment to the standard deviation of the drift model, if necessary to conservatively envelop the observed data population.

6.3.4 Time-Dependency

Per Reference 4.1.3, Scatter Plots and a time-based Binning Analysis are developed for the data to establish the time-dependency of the drift. If enough drift data exists for significantly different time intervals, regression analysis is performed to aid in the determination of time-dependency. The drift data is determined to be strongly time dependent or moderately time dependent, for the purpose of extrapolation.

6.3.5 Analyzed Drift Derivation and Characterization: The drift values are determined for the current calibration interval. These values are conservatively extrapolated to the desired calibration interval, based on the methods prescribed in Reference 4.1.3, depending on the degree of time-dependency derived for the drift data.

6.4 The mathematical computations of the statistical analysis are performed within an Excel spreadsheet. Supporting information from the spreadsheet is printed out in the form of Attachment 1 to this analysis. Microsoft Excel spreadsheets generally compute values to an approximate 15 decimal resolution, which is well beyond any required rounding for engineering analyses. However, for printing and display purposes, most values are displayed to lesser resolution. It is possible that hand computations will produce slightly different results, because of using rounded numbers in initial and intermediate steps, but the Excel computed values are considered highly accurate in comparison.

6.5 Acceptance Criteria: Since the purpose of the analysis is to generate a value and description of the characteristics of the drift of the evaluated make/model, there are no specific acceptance criteria.

7 Analysis 7.1 Gather and Generate Raw Error Data 7.1.1 Specifically, this analysis addresses ABB Model ITE-27H Undervoltage Relays, with the tag numbers as shown in Table 1.2-1 of this analysis. These relays have identical manufacturer and model numbers, identical settings, and are used in identical applications. Therefore, all data is properly pooled for analysis, and no specific pooling tests are required.

7.1.2 A screening of the initial input data from pages 1 through 3 of Attachment 1 was performed. To help identify erroneous data, an informal critical T-test was performed, with the Critical T values reduced incrementally until approximately 10%

of the data population was identified as outliers. Those outliers were researched,

DRIFT ANALYSIS G13.18.6.3-006 ENGINEERING DEPARTMENT Revision 0 RIVER BEND STATION PAGE 11 OF 14 and no data errors were revealed as shown in Table 7.1.4-1. The specific informal T-tests performed are not documented, as they are only used as tools to identify potentially erroneous data and do not contribute to the analysis of the valid data.

7.1.3 Pages 1 through 3 of Attachment 1 provide a listing of the initial As Found and As Left data from available historical plant calibration records for the subject UV Relays. Note that the calibration dates are also recorded, and notes are provided to clarify the activities performed or to provide additional information about the data, as appropriate. This data was entered into an Excel spreadsheet for computation of the drift values, time intervals between calibrations and statistical analysis.

7.1.4 Data not entered into the analysis is listed in the table below, showing the reasoning used in not entering the data.

Table 7.1.4-1 Data Not Entered in the Drift Analysis Procedure Tag Number Surveillance Comments/Disposition Number Date(s)

None None None None 7.1.5 Per the methodology of Section 4.1.1.11 of Reference 4.1.3, drift is computed by subtracting the As Left data of one calibration from the As Found data of the next calibration, as documented in pages 4 through 6 of Attachment 1. These pages also document the time interval between calibrations (in the number of days and months) by subtracting the As Left date of one calibration from the As Found date of the next calibration, per Section 4.1.1.10 of Reference 4.1.3. Pages 4 through 6 of Attachment 1 import the Sequence ID, the Tag No., the AF / AL flags, the dates of calibration and the As Found and As Left data from pages 1 through 3 of Attachment 1 and computes the interval between calibrations. Pages 4 and 5 of Attachment 1 compute the drift values and summarize the time intervals computed.

As an example of the equations used, the first drift value and time interval are computed as follows. The rest of the values are computed identically.

Drift (Seq 1)= AF (2/17/08) - AL (5/08/06) [For Tag ENS-SWG1A-27-1A]

= 48.90 (From Seq. 1 on Left) - 49.09 (From Seq. 4 on Left)

= -0.19 VAC Cal Interval (Seq 1) = 2/17/08 - 5/08/06

= 650 Days Cal Interval (Mo.) = Cal Interval (Days) x 12 Months / 365.25 Days

= 21.4 Months

DRIFT ANALYSIS G13.18.6.3-006 ENGINEERING DEPARTMENT Revision 0 RIVER BEND STATION PAGE 12 OF 14 7.2 Determination of Outliers and Statistical Summary 7.2.1 The outlier analysis is recorded on pages 7 and 8 of Attachment 1 to this drift analysis. This page displays the Sequence No., Tag No., Drift, and Calibration Interval (in units of Days). The critical T value used in the outlier analysis comes directly from Table 2 of Reference 4.1.3. As shown on page 7 of Attachment 1, one outlier was detected and removed. The Final Data Set (FDS) for this analysis is documented on pages 7 through 8 of Attachment 1 and, except for the one removed outlier, is identical to the original data set.

7.2.2 A summary of the required statistical values for the Final Data Set, per Section 4.2 of Reference 4.1.3, is developed on page 7 of Attachment 1. Cell formulas for the determinations of statistical quantities are used directly from Section 4.2 of Reference 4.1.3.

7.3 Tests for Normality 7.3.1 Since the FDS contains less than 50 samples, the W Test is performed on the data to test for normality, as shown on page 9 of Attachment 1. Per the methodology of Section 3.7.2 of Reference 4.1.3, the details of the W Test methodology are shown in Reference 4.1.7. Equations used are listed on page 9 of Attachment 1. Since the calculated W statistic (0.9569) is greater than the critical value for W (0.9410), this test does not reject the assumption of normality for this data set. Therefore, the data is established as normally distributed, and no coverage analysis is necessary.

7.3.2 Since the W Test did not reject the assumption of normality, a Coverage Analysis is not necessary, but a Histogram is developed for information only. The Histogram is developed and documented on pages 10 and 11 of Attachment 1, per Sections 3.7.5 and 4.4 of Reference 4.1.3. To generate the Histogram data, the drift values are categorized into 12 bins, in relation to the mean and standard deviation. These bins are generated in multiples of 1/2 Standard Deviation increments, and the bin maximum values are derived in accordance with the methods given in Section 19 of Reference 4.1.4. (See page 10 of Attachment 1 for specific formulas used for the maximums.)

The expected populations within each bin are developed from normal distribution percentages, as shown on page 10 of Attachment 1.

7.4 Time-Dependency 7.4.1 In order to determine time-dependency of the drift data, the data is first plotted as a scatter plot on page 12 of Attachment 1, in accordance with the methodology of Section 4.5.1 of Reference 4.1.3. The trend line within this scatter plot starts at a small negative value and crosses zero towards the end of the analysis period. The data scatter appears to increase slightly over time. The trend line and the associated equation are noted on the scatter plot on page 12 of Attachment 1.

7.4.2 The binning analysis is performed on page 13 of Attachment 1. The drift and time interval data are divided into bins, based on the intervals between calibrations as defined in Section 3.8.3.1 of Reference 4.1.3. Statistical summaries for each bin, including count, mean, standard deviation, mean time interval and maximum observed time interval are computed. Excel functions are used to determine the statistical summary values for each bin, and are used explicitly from Sections 4.2.1,

DRIFT ANALYSIS G13.18.6.3-006 ENGINEERING DEPARTMENT Revision 0 RIVER BEND STATION PAGE 13 OF 14 4.2.2, 4.2.3 and 4.2.7 of Reference 4.1.3. This information is presented on page 13 of Attachment 1. Per Section 3.8.3.4 of Reference 4.1.3, after removing those bins with 5 or less data points and those with less than or equal to 10% of total population, only Bins 4 and 5 remain.

Page 14 of Attachment 1 displays a plot of the mean and standard deviations of the drift data versus the average time interval between calibrations for the subject bins, in accordance with Section 4.5.2 of Reference 4.1.3. It also provides all of the binning parameters and statistics that are a part of the binning analysis. The mean value of the data starts from a negative value in Bin 4, crosses zero and goes positive for Bin 5. Also, from this plot, the standard deviation increases from Bin 4 to Bin 5. In addition, the ratio of the variances (Bin 5 / Bin 4) is compared to the F critical value, as directed by Section 4.5.2 of Reference 4.1.3. Only the standard deviation plot could be indicative of potential time dependency, but strong time dependency is not indicated from the variance test (Sections 3.8.3.4 and 4.5.2 of Reference 4.1.3).

7.4.3 Per Section 3.8.4 of Reference 4.1.3, a drift regression analysis is performed within pages 15 and 16 of Attachment 1 (labeled Regression-Drift). The equations and functions used by Excel are taken specifically from Section 3.8.4 of Reference 4.1.3.

The regression analysis output shows an R Squared Value (0.042874) less than 0.09, a P Value greater than 0.05 (0.193957) and F Value (1.746985) less than F Critical (3.238096). These results all indicate a bias portion of drift that is not time-dependent. Also, the regression line crosses zero within the analysis period, which per the last paragraph of Section 3.8.4 of Reference 4.1.3, is not expected and is an improper model of the drift-versus-time characteristic of the device. The fact that this is an improper model of the drift-versus-time characteristic of the device confirms the time-independent conclusion of the three statistical tests. The bias portion of drift is conservatively treated as moderately time-dependent for the purpose of extrapolation.

7.4.4 Per Section 3.8.4 of Reference 4.1.3, an absolute value drift regression analysis is performed within pages 17 and 18 of Attachment 1 (labeled Regression - AV of Drift). The drift data is converted into absolute value via the Excel ABS function for each drift data value. The equations and functions used by Excel for the Regression analysis are taken specifically from Section 3.8.4 of Reference 4.1.3.

This regression analysis output shows an R Squared Value (0.023738) less than 0.09, a P Value (0.336156) greater than 0.05, and an F Value (0.948294) less than F Critical (3.238096). These results all indicate a random portion of drift that is not significantly time-dependent. The absolute value drift regression line increases over time, and the binning plot shows an increasing standard deviation over time. Based on these results, per Section 3.8.4 of Reference 4.1.3, the random portion of drift is conservatively treated as moderately time-dependent for the purpose of extrapolation.

7.5 Analyzed Drift (DA) Derivation and Characterization 7.5.1 As shown on page 19 of Attachment 1, per Section 3.11 of Reference 4.1.3, the drift bias error is evaluated for significance. The critical value for significance of the bias term is computed and shown therein. The bias is determined to be negligible.

Therefore, the computed Analyzed Drift Bias term (DAbias) is negligible.

DRIFT ANALYSIS G13.18.6.3-006 ENGINEERING DEPARTMENT Revision 0 RIVER BEND STATION PAGE 14 OF 14 7.5.2 Per Section 4.6.6 of Reference 4.1.3, the random portion of the Analyzed Drift is determined from multiplying the standard deviation of Bin 5 by the Tolerance Interval Factor (TIF), and extrapolating as required to a calibration interval of 30 months. The random portion of drift has been determined to be moderately time-dependent for the purpose of extrapolation. For conservatism, the standard deviation of Bin 5 is used with the average observed time interval from Bin 5 on page 13 of Attachment 1 as the starting point. The TIF is obtained from Table 1 of Reference 4.1.3 as 2.445 for a 95/95 significance. The computation of this value is shown on page 19 of Attachment 1 to result in a DArandom(extrap) term of ! 0.392 VAC for a 30 month (24 months + 25%) calibration interval.

8 Attachments Attachment 1 - Analysis Spreadsheet (19 pages)

Spreadsheet Contents Pages Input Data 1-3 AF-AL Data 4-6 Outliers & Summary 7-8 W Test 9 Histogram 10-11 Scatter Plot 12 Binning Analysis 13-14 Regression - Drift 15-16 Regression - AV of Drift 17-18 Analyzed Drift (DA) 19 Attachment 2 - DVR Form (8 pages)

DRIFT ANALYSIS ABB/ITE-27H G13.18.6.3-006 Rev 0 RIVER BEND STATION Undervoltage Relays Attachment 1 Input Data Page 1 of19 AF/ AF / AL Seq. ID Tag ID Date Procedure Make/Model AL Setpt Data Units Comments 1 ENS-SWG1A-27-1A (UV) 2/17/2008 STP-302-1600 ABB/ITE-27H AF 49.0 48.90 VAC 2 ENS-SWG1A-27-1A (UV) 2/17/2008 STP-302-1600 ABB/ITE-27H AL 49.0 48.90 VAC 3 ENS-SWG1A-27-1A (UV) 5/8/2006 STP-302-1600 ABB/ITE-27H AF 49.0 49.10 VAC 4 ENS-SWG1A-27-1A (UV) 5/8/2006 STP-302-1600 ABB/ITE-27H AL 49.0 49.09 VAC 5 ENS-SWG1A-27-1A (UV) 11/11/2004 STP-302-1600 ABB/ITE-27H AF 49.0 49.10 VAC 6 ENS-SWG1A-27-1A (UV) 11/11/2004 STP-302-1600 ABB/ITE-27H AL 49.0 49.10 VAC 7 ENS-SWG1A-27-1A (UV) 3/29/2003 STP-302-1600 ABB/ITE-27H AF 49.0 48.80 VAC 8 ENS-SWG1A-27-1A (UV) 3/29/2003 STP-302-1600 ABB/ITE-27H AL 49.0 49.01 VAC 9 ENS-SWG1A-27-1A (UV) 9/27/2001 STP-302-1600 ABB/ITE-27H AF 49.0 49.00 VAC 10 ENS-SWG1A-27-1A (UV) 9/27/2001 STP-302-1600 ABB/ITE-27H AL 49.0 49.00 VAC 11 ENS-SWG1A-27-1A (UV) 3/10/2000 STP-302-1600 ABB/ITE-27H AF 49.0 48.90 VAC 12 ENS-SWG1A-27-1A (UV) 3/10/2000 STP-302-1600 ABB/ITE-27H AL 49.0 48.90 VAC 13 ENS-SWG1A-27-1A (UV) 4/21/1999 STP-302-1600 ABB/ITE-27H AF 49.0 49.00 VAC 14 ENS-SWG1A-27-1A (UV) 4/21/1999 STP-302-1600 ABB/ITE-27H AL 49.0 49 0 49.00 49 00 VAC 15 ENS-SWG1A-27-1A (UV) 9/19/1997 STP-302-1600 ABB/ITE-27H AF 49.0 49.00 VAC 16 ENS-SWG1A-27-1A (UV) 9/19/1997 STP-302-1600 ABB/ITE-27H AL 49.0 49.00 VAC 17 ENS-SWG1A-27-1B (UV) 2/17/2008 STP-302-1600 ABB/ITE-27H AF 49.0 49.90 VAC 18 ENS-SWG1A-27-1B (UV) 2/17/2008 STP-302-1600 ABB/ITE-27H AL 49.0 49.30 VAC 19 ENS-SWG1A-27-1B (UV) 5/8/2006 STP-302-1600 ABB/ITE-27H AF 49.0 49.22 VAC 20 ENS-SWG1A-27-1B (UV) 5/8/2006 STP-302-1600 ABB/ITE-27H AL 49.0 49.18 VAC 21 ENS-SWG1A-27-1B (UV) 11/11/2004 STP-302-1600 ABB/ITE-27H AF 49.0 49.10 VAC 22 ENS-SWG1A-27-1B (UV) 11/11/2004 STP-302-1600 ABB/ITE-27H AL 49.0 49.10 VAC 23 ENS-SWG1A-27-1B (UV) 3/29/2003 STP-302-1600 ABB/ITE-27H AF 49.0 48.40 VAC 24 ENS-SWG1A-27-1B (UV) 3/29/2003 STP-302-1600 ABB/ITE-27H AL 49.0 49.10 VAC 25 ENS-SWG1A-27-1B (UV) 9/27/2001 STP-302-1600 ABB/ITE-27H AF 49.0 48.50 VAC 26 ENS-SWG1A-27-1B (UV) 9/27/2001 STP-302-1600 ABB/ITE-27H AL 49.0 48.50 VAC 27 ENS-SWG1A-27-1B (UV) 3/10/2000 STP-302-1600 ABB/ITE-27H AF 49.0 48.50 VAC 28 ENS-SWG1A-27-1B (UV) 3/10/2000 STP-302-1600 ABB/ITE-27H AL 49.0 48.50 VAC 29 ENS-SWG1A-27-1B (UV) 4/21/1999 STP-302-1600 ABB/ITE-27H AF 49.0 48.60 VAC 30 ENS-SWG1A-27-1B (UV) 4/21/1999 STP-302-1600 ABB/ITE-27H AL 49.0 48.60 VAC 31 ENS-SWG1A-27-1B (UV) 9/19/1997 STP-302-1600 ABB/ITE-27H AF 49.0 48.60 VAC 32 ENS-SWG1A-27-1B (UV) 9/19/1997 STP-302-1600 ABB/ITE-27H AL 49.0 48.60 VAC 33 ENS-SWG1A-27-1C (UV) 2/17/2008 STP-302-1600 ABB/ITE-27H AF 49.0 50.00 VAC 34 ENS-SWG1A-27-1C (UV) 2/17/2008 STP-302-1600 ABB/ITE-27H AL 49.0 49.20 VAC 35 ENS-SWG1A-27-1C (UV) 5/8/2006 STP-302-1600 ABB/ITE-27H AF 49.0 48.80 VAC 36 ENS-SWG1A-27-1C (UV) 5/8/2006 STP-302-1600 ABB/ITE-27H AL 49.0 49.70 VAC

DRIFT ANALYSIS ABB/ITE-27H G13.18.6.3-006 Rev 0 RIVER BEND STATION Undervoltage Relays Attachment 1 Input Data Page 2 of19 AF/ AF / AL Seq. ID Tag ID Date Procedure Make/Model AL Setpt Data Units Comments 37 ENS-SWG1A-27-1C (UV) 11/11/2004 STP-302-1600 ABB/ITE-27H AF 49.0 49.20 VAC 38 ENS-SWG1A-27-1C (UV) 11/11/2004 STP-302-1600 ABB/ITE-27H AL 49.0 49.20 VAC 39 ENS-SWG1A-27-1C (UV) 3/29/2003 STP-302-1600 ABB/ITE-27H AF 49.0 48.32 VAC 40 ENS-SWG1A-27-1C (UV) 3/29/2003 STP-302-1600 ABB/ITE-27H AL 49.0 49.06 VAC 41 ENS-SWG1A-27-1C (UV) 9/27/2001 STP-302-1600 ABB/ITE-27H AF 49.0 48.21 VAC 42 ENS-SWG1A-27-1C (UV) 9/27/2001 STP-302-1600 ABB/ITE-27H AL 49.0 48.21 VAC 43 ENS-SWG1A-27-1C (UV) 3/10/2000 STP-302-1600 ABB/ITE-27H AF 49.0 48.30 VAC 44 ENS-SWG1A-27-1C (UV) 3/10/2000 STP-302-1600 ABB/ITE-27H AL 49.0 48.30 VAC 45 ENS-SWG1A-27-1C (UV) 4/21/1999 STP-302-1600 ABB/ITE-27H AF 49.0 48.30 VAC 46 ENS-SWG1A-27-1C (UV) 4/21/1999 STP-302-1600 ABB/ITE-27H AL 49.0 48.30 VAC 47 ENS-SWG1A-27-1C (UV) 9/19/1997 STP-302-1600 ABB/ITE-27H AF 49.0 48.20 VAC 48 ENS-SWG1A-27-1C (UV) 9/19/1997 STP-302-1600 ABB/ITE-27H AL 49.0 48.30 VAC 49 ENS-SWG1B-27-1A (UV) 2/1/2008 STP-302-1601 ABB/ITE-27H AF 49.0 48.90 VAC 50 ENS-SWG1B-27-1A ENS SWG1B 27 1A (UV) 2/1/2008 STP-302-1601 STP 302 1601 ABB/ITE-27H ABB/ITE 27H AL 49.0 49 0 48.90 48 90 VAC 51 ENS-SWG1B-27-1A (UV) 4/29/2006 STP-302-1601 ABB/ITE-27H AF 49.0 48.68 VAC 52 ENS-SWG1B-27-1A (UV) 4/29/2006 STP-302-1601 ABB/ITE-27H AL 49.0 48.78 VAC 53 ENS-SWG1B-27-1A (UV) 10/31/2004 STP-302-1601 ABB/ITE-27H AF 49.0 48.70 VAC 54 ENS-SWG1B-27-1A (UV) 10/31/2004 STP-302-1601 ABB/ITE-27H AL 49.0 48.70 VAC 55 ENS-SWG1B-27-1A (UV) 3/20/2003 STP-302-1601 ABB/ITE-27H AF 49.0 48.80 VAC 56 ENS-SWG1B-27-1A (UV) 3/20/2003 STP-302-1601 ABB/ITE-27H AL 49.0 48.80 VAC 57 ENS-SWG1B-27-1A (UV) 10/6/2001 STP-302-1601 ABB/ITE-27H AF 49.0 48.83 VAC 58 ENS-SWG1B-27-1A (UV) 10/6/2001 STP-302-1601 ABB/ITE-27H AL 49.0 48.83 VAC 59 ENS-SWG1B-27-1A (UV) 3/25/2000 STP-302-1601 ABB/ITE-27H AF 49.0 48.75 VAC 60 ENS-SWG1B-27-1A (UV) 3/25/2000 STP-302-1601 ABB/ITE-27H AL 49.0 48.85 VAC 61 ENS-SWG1B-27-1A (UV) 4/30/1999 STP-302-1601 ABB/ITE-27H AF 49.0 48.83 VAC 62 ENS-SWG1B-27-1A (UV) 4/30/1999 STP-302-1601 ABB/ITE-27H AL 49.0 48.83 VAC 63 ENS-SWG1B-27-1A (UV) 10/4/1997 STP-302-1601 ABB/ITE-27H AF 49.0 48.80 VAC 64 ENS-SWG1B-27-1A (UV) 10/4/1997 STP-302-1601 ABB/ITE-27H AL 49.0 48.80 VAC 65 ENS-SWG1B-27-1B (UV) 2/1/2008 STP-302-1601 ABB/ITE-27H AF 49.0 48.97 VAC 66 ENS-SWG1B-27-1B (UV) 2/1/2008 STP-302-1601 ABB/ITE-27H AL 49.0 49.00 VAC 67 ENS-SWG1B-27-1B (UV) 4/29/2006 STP-302-1601 ABB/ITE-27H AF 49.0 48.77 VAC 68 ENS-SWG1B-27-1B (UV) 4/29/2006 STP-302-1601 ABB/ITE-27H AL 49.0 48.77 VAC 69 ENS-SWG1B-27-1B (UV) 10/31/2004 STP-302-1601 ABB/ITE-27H AF 49.0 48.80 VAC 70 ENS-SWG1B-27-1B (UV) 10/31/2004 STP-302-1601 ABB/ITE-27H AL 49.0 48.80 VAC 71 ENS-SWG1B-27-1B (UV) 3/20/2003 STP-302-1601 ABB/ITE-27H AF 49.0 48.80 VAC 72 ENS-SWG1B-27-1B (UV) 3/20/2003 STP-302-1601 ABB/ITE-27H AL 49.0 48.80 VAC

DRIFT ANALYSIS ABB/ITE-27H G13.18.6.3-006 Rev 0 RIVER BEND STATION Undervoltage Relays Attachment 1 Input Data Page 3 of19 AF/ AF / AL Seq. ID Tag ID Date Procedure Make/Model AL Setpt Data Units Comments 73 ENS-SWG1B-27-1B (UV) 10/6/2001 STP-302-1601 ABB/ITE-27H AF 49.0 48.72 VAC 74 ENS-SWG1B-27-1B (UV) 10/6/2001 STP-302-1601 ABB/ITE-27H AL 49.0 48.72 VAC 75 ENS-SWG1B-27-1B (UV) 3/25/2000 STP-302-1601 ABB/ITE-27H AF 49.0 48.80 VAC 76 ENS-SWG1B-27-1B (UV) 3/25/2000 STP-302-1601 ABB/ITE-27H AL 49.0 48.75 VAC 77 ENS-SWG1B-27-1B (UV) 4/30/1999 STP-302-1601 ABB/ITE-27H AF 49.0 48.82 VAC 78 ENS-SWG1B-27-1B (UV) 4/30/1999 STP-302-1601 ABB/ITE-27H AL 49.0 48.83 VAC 79 ENS-SWG1B-27-1B (UV) 10/4/1997 STP-302-1601 ABB/ITE-27H AF 49.0 48.60 VAC 80 ENS-SWG1B-27-1B (UV) 10/4/1997 STP-302-1601 ABB/ITE-27H AL 49.0 48.70 VAC 81 ENS-SWG1B-27-1C (UV) 2/1/2008 STP-302-1601 ABB/ITE-27H AF 49.0 48.90 VAC 82 ENS-SWG1B-27-1C (UV) 2/1/2008 STP-302-1601 ABB/ITE-27H AL 49.0 48.92 VAC 83 ENS-SWG1B-27-1C (UV) 4/29/2006 STP-302-1601 ABB/ITE-27H AF 49.0 48.78 VAC 84 ENS-SWG1B-27-1C (UV) 4/29/2006 STP-302-1601 ABB/ITE-27H AL 49.0 48.88 VAC 85 ENS-SWG1B-27-1C (UV) 10/31/2004 STP-302-1601 ABB/ITE-27H AF 49.0 48.70 VAC 86 ENS-SWG1B-27-1C ENS SWG1B 27 1C (UV) 10/31/2004 STP-302-1601 STP 302 1601 ABB/ITE-27H ABB/ITE 27H AL 49.0 49 0 48.70 48 70 VAC 87 ENS-SWG1B-27-1C (UV) 3/20/2003 STP-302-1601 ABB/ITE-27H AF 49.0 48.80 VAC 88 ENS-SWG1B-27-1C (UV) 3/20/2003 STP-302-1601 ABB/ITE-27H AL 49.0 48.80 VAC 89 ENS-SWG1B-27-1C (UV) 10/6/2001 STP-302-1601 ABB/ITE-27H AF 49.0 48.72 VAC 90 ENS-SWG1B-27-1C (UV) 10/6/2001 STP-302-1601 ABB/ITE-27H AL 49.0 48.72 VAC 91 ENS-SWG1B-27-1C (UV) 3/25/2000 STP-302-1601 ABB/ITE-27H AF 49.0 48.84 VAC 92 ENS-SWG1B-27-1C (UV) 3/25/2000 STP-302-1601 ABB/ITE-27H AL 49.0 48.84 VAC 93 ENS-SWG1B-27-1C (UV) 4/30/1999 STP-302-1601 ABB/ITE-27H AF 49.0 48.83 VAC 94 ENS-SWG1B-27-1C (UV) 4/30/1999 STP-302-1601 ABB/ITE-27H AL 49.0 48.73 VAC 95 ENS-SWG1B-27-1C (UV) 10/4/1997 STP-302-1601 ABB/ITE-27H AF 49.0 48.80 VAC 96 ENS-SWG1B-27-1C (UV) 10/4/1997 STP-302-1601 ABB/ITE-27H AL 49.0 48.70 VAC

DRIFT ANALYSIS ABB/ITE-27H G13.18.6.3-006 Rev 0 RIVER BEND STATION Undervoltage Relays Attachment 1 AF-AL Data Page 4 of19 CAL INTERVAL = DRIFT = (Current CAL INTERVAL =

AF/AL DATA OUTLIERS Seq. CAL DATE AF/AL (Current Date - Seq. Cal AF Data - Prev (Current Date -

VALUE COMMENTS Previous Date) Cal AL Data) Previous Date)

ID Make/Model Number Tag ID mm/dd/yy Status (VAC) Days Months ID Tag Number (VAC) Days Months 1 ABB/ITE-27H ENS-SWG1A-27-1A (UV) 02/17/08 AF 48.90 650 21.4 1 ENS-SWG1A-27-1A (UV) -0.19 650 21.4 2 ABB/ITE-27H ENS-SWG1A-27-1A (UV) 02/17/08 AL 48.90 3 ENS-SWG1A-27-1A (UV) 0.00 543 17.8 3 ABB/ITE-27H ENS-SWG1A-27-1A (UV) 05/08/06 AF 49.10 543 17.8 5 ENS-SWG1A-27-1A (UV) 0.09 593 19.5 4 ABB/ITE-27H ENS-SWG1A-27-1A (UV) 05/08/06 AL 49.09 7 ENS-SWG1A-27-1A (UV) -0.20 548 18.0 5 ABB/ITE-27H ENS-SWG1A-27-1A (UV) 11/11/04 AF 49.10 593 19.5 9 ENS-SWG1A-27-1A (UV) 0.10 566 18.6 6 ABB/ITE-27H ENS-SWG1A-27-1A (UV) 11/11/04 AL 49.10 11 ENS-SWG1A-27-1A (UV) -0.10 324 10.6 7 ABB/ITE-27H ENS-SWG1A-27-1A (UV) 03/29/03 AF 48.80 548 18.0 13 ENS-SWG1A-27-1A (UV) 0.00 579 19.0 8 ABB/ITE-27H ENS-SWG1A-27-1A (UV) 03/29/03 AL 49.01 9 ABB/ITE-27H ENS-SWG1A-27-1A (UV) 09/27/01 AF 49.00 566 18.6 17 ENS-SWG1A-27-1B (UV) 0.72 650 21.4 10 ABB/ITE-27H ENS-SWG1A-27-1A (UV) 09/27/01 AL 49.00 19 ENS-SWG1A-27-1B (UV) 0.12 543 17.8 11 ABB/ITE-27H ENS-SWG1A-27-1A (UV) 03/10/00 AF 48.90 324 10.6 21 ENS-SWG1A-27-1B (UV) 0.00 593 19.5 12 ABB/ITE-27H ENS-SWG1A-27-1A (UV) 03/10/00 AL 48.90 23 ENS-SWG1A-27-1B (UV) -0.10 548 18.0 13 ABB/ITE-27H ENS-SWG1A-27-1A (UV) 04/21/99 AF 49.00 579 19.0 25 ENS-SWG1A-27-1B (UV) 0.00 566 18.6 14 ABB/ITE-27H ENS-SWG1A-27-1A (UV) 04/21/99 AL 49.00 27 ENS-SWG1A-27-1B (UV) -0.10 324 10.6 15 ABB/ITE-27H ENS-SWG1A-27-1A (UV) 09/19/97 AF 49.00 29 ENS-SWG1A-27-1B (UV) 0.00 579 19.0 16 ABB/ITE-27H ENS-SWG1A-27-1A (UV) 09/19/97 AL 49.00 Identified as 17 ABB/ITE-27H ENS-SWG1A-27-1B (UV) 02/17/08 AF 49.90 Outlier and 650 21.4 33 ENS-SWG1A-27-1C (UV) 0.30 650 21.4 removed 18 ABB/ITE-27H ENS-SWG1A-27-1B (UV) 02/17/08 AL 49.30 35 ENS-SWG1A-27-1C (UV) -0.40 543 17.8 19 ABB/ITE-27H ENS-SWG1A-27-1B (UV) 05/08/06 AF 49.22 543 17.8 37 ENS-SWG1A-27-1C (UV) 0.14 593 19.5 20 ABB/ITE-27H ENS-SWG1A-27-1B (UV) 05/08/06 AL 49.18 39 ENS-SWG1A-27-1C (UV) 0.11 548 18.0 21 ABB/ITE-27H ENS-SWG1A-27-1B (UV) 11/11/04 AF 49.10 593 19.5 41 ENS-SWG1A-27-1C (UV) -0.09 566 18.6 22 ABB/ITE-27H ENS-SWG1A-27-1B (UV) 11/11/04 AL 49.10 43 ENS-SWG1A-27-1C (UV) 0.00 324 10.6 23 ABB/ITE-27H ENS-SWG1A-27-1B (UV) 03/29/03 AF 48.40 548 18.0 45 ENS-SWG1A-27-1C (UV) 0.00 579 19.0 24 ABB/ITE-27H ENS-SWG1A-27-1B (UV) 03/29/03 AL 49.10 25 ABB/ITE-27H ENS-SWG1A-27-1B (UV) 09/27/01 AF 48.50 566 18.6 49 ENS-SWG1B-27-1A (UV) 0.12 643 21.1 26 ABB/ITE-27H ENS-SWG1A-27-1B (UV) 09/27/01 AL 48.50 51 ENS-SWG1B-27-1A (UV) -0.02 545 17.9 27 ABB/ITE-27H ENS-SWG1A-27-1B (UV) 03/10/00 AF 48.50 324 10.6 53 ENS-SWG1B-27-1A (UV) -0.10 591 19.4 28 ABB/ITE-27H ENS-SWG1A-27-1B (UV) 03/10/00 AL 48.50 55 ENS-SWG1B-27-1A (UV) -0.03 530 17.4 29 ABB/ITE-27H ENS-SWG1A-27-1B (UV) 04/21/99 AF 48.60 579 19.0 57 ENS-SWG1B-27-1A (UV) -0.02 560 18.4 30 ABB/ITE-27H ENS-SWG1A-27-1B (UV) 04/21/99 AL 48.60 59 ENS-SWG1B-27-1A (UV) -0.08 330 10.8 31 ABB/ITE-27H ENS-SWG1A-27-1B (UV) 09/19/97 AF 48.60 61 ENS-SWG1B-27-1A (UV) 0.03 573 18.8 32 ABB/ITE-27H ENS-SWG1A-27-1B (UV) 09/19/97 AL 48.60 33 ABB/ITE-27H ENS-SWG1A-27-1C (UV) 02/17/08 AF 50.00 650 21.4 65 ENS-SWG1B-27-1B (UV) 0.20 643 21.1 34 ABB/ITE-27H ENS-SWG1A-27-1C (UV) 02/17/08 AL 49.20 67 ENS-SWG1B-27-1B (UV) -0.03 545 17.9

DRIFT ANALYSIS ABB/ITE-27H G13.18.6.3-006 Rev 0 RIVER BEND STATION Undervoltage Relays Attachment 1 AF-AL Data Page 5 of19 CAL INTERVAL = DRIFT = (Current CAL INTERVAL =

AF/AL DATA OUTLIERS Seq. CAL DATE AF/AL (Current Date - Seq. Cal AF Data - Prev (Current Date -

VALUE COMMENTS Previous Date) Cal AL Data) Previous Date)

ID Make/Model Number Tag ID mm/dd/yy Status (VAC) Days Months ID Tag Number (VAC) Days Months 35 ABB/ITE-27H ENS-SWG1A-27-1C (UV) 05/08/06 AF 48.80 543 17.8 69 ENS-SWG1B-27-1B (UV) 0.00 591 19.4 36 ABB/ITE-27H ENS-SWG1A-27-1C (UV) 05/08/06 AL 49.70 71 ENS-SWG1B-27-1B (UV) 0.08 530 17.4 37 ABB/ITE-27H ENS-SWG1A-27-1C (UV) 11/11/04 AF 49.20 593 19.5 73 ENS-SWG1B-27-1B (UV) -0.03 560 18.4 38 ABB/ITE-27H ENS-SWG1A-27-1C (UV) 11/11/04 AL 49.20 75 ENS-SWG1B-27-1B (UV) -0.03 330 10.8 39 ABB/ITE-27H ENS-SWG1A-27-1C (UV) 03/29/03 AF 48.32 548 18.0 77 ENS-SWG1B-27-1B (UV) 0.12 573 18.8 40 ABB/ITE-27H ENS-SWG1A-27-1C (UV) 03/29/03 AL 49.06 41 ABB/ITE-27H ENS-SWG1A-27-1C (UV) 09/27/01 AF 48.21 566 18.6 81 ENS-SWG1B-27-1C (UV) 0.02 643 21.1 42 ABB/ITE-27H ENS-SWG1A-27-1C (UV) 09/27/01 AL 48.21 83 ENS-SWG1B-27-1C (UV) 0.08 545 17.9 43 ABB/ITE-27H ENS-SWG1A-27-1C (UV) 03/10/00 AF 48.30 324 10.6 85 ENS-SWG1B-27-1C (UV) -0.10 591 19.4 44 ABB/ITE-27H ENS-SWG1A-27-1C (UV) 03/10/00 AL 48.30 87 ENS-SWG1B-27-1C (UV) 0.08 530 17.4 45 ABB/ITE-27H ENS-SWG1A-27-1C (UV) 04/21/99 AF 48.30 579 19.0 89 ENS-SWG1B-27-1C (UV) -0.12 560 18.4 46 ABB/ITE-27H ENS-SWG1A-27-1C (UV) 04/21/99 AL 48.30 91 ENS-SWG1B-27-1C (UV) 0.11 330 10.8 47 ABB/ITE-27H ENS-SWG1A-27-1C (UV) 09/19/97 AF 48.20 93 ENS-SWG1B-27-1C (UV) 0.13 573 18.8 48 ABB/ITE-27H ENS-SWG1A-27-1C (UV) 09/19/97 AL 48.30 49 ABB/ITE-27H ENS-SWG1B-27-1A (UV) 02/01/08 AF 48.90 643 21.1 50 ABB/ITE-27H ENS-SWG1B-27-1A (UV) 02/01/08 AL 48.90 51 ABB/ITE-27H ENS-SWG1B-27-1A (UV) 04/29/06 AF 48.68 545 17.9 52 ABB/ITE-27H ENS-SWG1B-27-1A (UV) 04/29/06 AL 48.78 53 ABB/ITE-27H ENS-SWG1B-27-1A (UV) 10/31/04 AF 48.70 591 19.4 54 ABB/ITE-27H ENS-SWG1B-27-1A (UV) 10/31/04 AL 48.70 55 ABB/ITE-27H ENS-SWG1B-27-1A (UV) 03/20/03 AF 48.80 530 17.4 56 ABB/ITE-27H ENS-SWG1B-27-1A (UV) 03/20/03 AL 48.80 57 ABB/ITE-27H ENS-SWG1B-27-1A (UV) 10/06/01 AF 48.83 560 18.4 58 ABB/ITE-27H ENS-SWG1B-27-1A (UV) 10/06/01 AL 48.83 59 ABB/ITE-27H ENS-SWG1B-27-1A (UV) 03/25/00 AF 48.75 330 10.8 60 ABB/ITE-27H ENS-SWG1B-27-1A (UV) 03/25/00 AL 48.85 61 ABB/ITE-27H ENS-SWG1B-27-1A (UV) 04/30/99 AF 48.83 573 18.8 62 ABB/ITE-27H ENS-SWG1B-27-1A (UV) 04/30/99 AL 48.83 63 ABB/ITE-27H ENS-SWG1B-27-1A (UV) 10/04/97 AF 48.80 64 ABB/ITE-27H ENS-SWG1B-27-1A (UV) 10/04/97 AL 48.80 65 ABB/ITE-27H ENS-SWG1B-27-1B (UV) 02/01/08 AF 48.97 643 21.1 66 ABB/ITE-27H ENS-SWG1B-27-1B (UV) 02/01/08 AL 49.00 67 ABB/ITE-27H ENS-SWG1B-27-1B (UV) 04/29/06 AF 48.77 545 17.9 68 ABB/ITE-27H ENS-SWG1B-27-1B (UV) 04/29/06 AL 48.77 69 ABB/ITE-27H ENS-SWG1B-27-1B (UV) 10/31/04 AF 48.80 591 19.4 70 ABB/ITE-27H ENS-SWG1B-27-1B (UV) 10/31/04 AL 48.80

DRIFT ANALYSIS ABB/ITE-27H G13.18.6.3-006 Rev 0 RIVER BEND STATION Undervoltage Relays Attachment 1 AF-AL Data Page 6 of19 CAL INTERVAL = DRIFT = (Current CAL INTERVAL =

AF/AL DATA OUTLIERS Seq. CAL DATE AF/AL (Current Date - Seq. Cal AF Data - Prev (Current Date -

VALUE COMMENTS Previous Date) Cal AL Data) Previous Date)

ID Make/Model Number Tag ID mm/dd/yy Status (VAC) Days Months ID Tag Number (VAC) Days Months 71 ABB/ITE-27H ENS-SWG1B-27-1B (UV) 03/20/03 AF 48.80 530 17.4 72 ABB/ITE-27H ENS-SWG1B-27-1B (UV) 03/20/03 AL 48.80 73 ABB/ITE-27H ENS-SWG1B-27-1B (UV) 10/06/01 AF 48.72 560 18.4 74 ABB/ITE-27H ENS-SWG1B-27-1B (UV) 10/06/01 AL 48.72 75 ABB/ITE-27H ENS-SWG1B-27-1B (UV) 03/25/00 AF 48.80 330 10.8 76 ABB/ITE-27H ENS-SWG1B-27-1B (UV) 03/25/00 AL 48.75 77 ABB/ITE-27H ENS-SWG1B-27-1B (UV) 04/30/99 AF 48.82 573 18.8 78 ABB/ITE-27H ENS-SWG1B-27-1B (UV) 04/30/99 AL 48.83 79 ABB/ITE-27H ENS-SWG1B-27-1B (UV) 10/04/97 AF 48.60 80 ABB/ITE-27H ENS-SWG1B-27-1B (UV) 10/04/97 AL 48.70 81 ABB/ITE-27H ENS-SWG1B-27-1C (UV) 02/01/08 AF 48.90 643 21.1 82 ABB/ITE-27H ENS-SWG1B-27-1C (UV) 02/01/08 AL 48.92 83 ABB/ITE-27H ENS-SWG1B-27-1C (UV) 04/29/06 AF 48.78 545 17.9 84 ABB/ITE-27H ENS-SWG1B-27-1C (UV) 04/29/06 AL 48.88 85 ABB/ITE-27H ENS-SWG1B-27-1C (UV) 10/31/04 AF 48.70 591 19.4 86 ABB/ITE-27H ENS-SWG1B-27-1C (UV) 10/31/04 AL 48.70 87 ABB/ITE-27H ENS-SWG1B-27-1C (UV) 03/20/03 AF 48.80 530 17.4 88 ABB/ITE-27H ENS-SWG1B-27-1C (UV) 03/20/03 AL 48.80 89 ABB/ITE-27H ENS-SWG1B-27-1C (UV) 10/06/01 AF 48.72 560 18.4 90 ABB/ITE-27H ENS-SWG1B-27-1C (UV) 10/06/01 AL 48.72 91 ABB/ITE-27H ENS-SWG1B-27-1C (UV) 03/25/00 AF 48.84 330 10.8 92 ABB/ITE-27H ENS-SWG1B-27-1C (UV) 03/25/00 AL 48.84 93 ABB/ITE-27H ENS-SWG1B-27-1C (UV) 04/30/99 AF 48.83 573 18.8 94 ABB/ITE-27H ENS-SWG1B-27-1C (UV) 04/30/99 AL 48.73 95 ABB/ITE-27H ENS-SWG1B-27-1C (UV) 10/04/97 AF 48.80 96 ABB/ITE-27H ENS-SWG1B-27-1C (UV) 10/04/97 AL 48.70

DRIFT ANALYSIS ABB/ITE-27H G13.18.6.3-006 Rev 0 RIVER BEND STATION Undervoltage Relays Attachment 1 Outliers & Summary Page 7 of19 Extreme Final Drift Drift Cal Interval Cal Interval Seq. ID Tag ID Studentized Data Set (VAC) (Days) (Days)

Deviate (T) (VAC) 1 ENS-SWG1A-27-1A (UV) -0.19 650 1.281 -0.19 650 3 ENS-SWG1A-27-1A (UV) 0.00 543 0.118 Raw Drift Data Statistics Summary 0.00 543 5 ENS-SWG1A-27-1A (UV) 0.09 593 0.433 (Initial Data Set) 0.09 593 7 ENS-SWG1A-27-1A (UV) -0.20 548 1.342 Mean (Average) 0.0193 -0.20 548 9 ENS-SWG1A-27-1A (UV) 0.10 566 0.494 Variance 0.0267 0.10 566 11 ENS-SWG1A-27-1A (UV) -0.10 324 0.730 Std. Dev. 0.1634 -0.10 324 13 ENS-SWG1A-27-1A (UV) 0.00 579 0.118 Sample Size (Count) 42 0.00 579 Maximum 0.72 17 ENS-SWG1A-27-1B (UV) 0.72 650 4.288 Median 0.00 OUTLIER OUTLIER 19 ENS-SWG1A-27-1B (UV) 0.12 543 0.616 Minimum -0.40 0.12 543 21 ENS-SWG1A-27-1B (UV) 0.00 593 0.118 Range 1.12 0.00 593 23 ENS-SWG1A-27-1B (UV) -0.10 548 0.730 Sum 0.810 -0.10 548 25 ENS-SWG1A-27-1B (UV) 0.00 566 0.118 Kurtosis 8.098 0.00 566 27 ENS-SWG1A-27-1B (UV) -0.10 324 0.730 Skewness 1.607 -0.10 324 29 ENS SWG1A 27 1B (UV)

ENS-SWG1A-27-1B 0 00 0.00 579 0 118 0.118 0 00 0.00 579 Critical T-Value (Upper 5% Signif.) 2.92 33 ENS-SWG1A-27-1C (UV) 0.30 650 1.718 0.30 650 35 ENS-SWG1A-27-1C (UV) -0.40 543 2.566 Equation for Each Studentized Deviate: T= lDrift-Meanl/Std. Dev. -0.40 543 37 ENS-SWG1A-27-1C (UV) 0.14 593 0.739 Crit T Value Lookup Value from Ref. 4.1.3 Table 2, per sample 0.14 593 39 ENS-SWG1A-27-1C (UV) 0.11 548 0.555 size. See Sections 3.6.1 and 3.6.2 of Reference 4.1.3. 0.11 548 41 ENS-SWG1A-27-1C (UV) -0.09 566 0.669 Outliers will be Denoted as such in "Final Data Set" column. -0.09 566 43 ENS-SWG1A-27-1C (UV) 0.00 324 0.118 One Outlier Detected and Removed (Seq. 17) 0.00 324 45 ENS-SWG1A-27-1C (UV) 0.00 579 0.118 0.00 579 Drift Data Statistics Summary 49 ENS-SWG1B-27-1A (UV) 0.12 643 0.616 (Final Data Set) 0.12 643 51 ENS-SWG1B-27-1A (UV) -0.02 545 0.240 Mean (Average) 0.0022 -0.02 545 53 ENS-SWG1B-27-1A (UV) -0.10 591 0.730 Variance 0.0148 -0.10 591 55 ENS-SWG1B-27-1A (UV) -0.03 530 0.302 Std. Dev. 0.1216 -0.03 530 57 ENS-SWG1B-27-1A (UV) -0.02 560 0.240 Sample Size (Count) 41 -0.02 560 59 ENS-SWG1B-27-1A (UV) -0.08 330 0.608 Maximum 0.30 -0.08 330 61 ENS-SWG1B-27-1A (UV) 0.03 573 0.066 Median 0.00 0.03 573 Minimum -0.40 65 ENS-SWG1B-27-1B (UV) 0.20 643 1.106 Range 0.70 0.20 643 67 ENS-SWG1B-27-1B (UV) -0.03 545 0.302 Sum 0.090 -0.03 545 69 ENS-SWG1B-27-1B (UV) 0.00 591 0.118 Kurtosis 2.234 0.00 591 71 ENS-SWG1B-27-1B (UV) 0.08 530 0.372 Skewness -0.581 0.08 530

DRIFT ANALYSIS ABB/ITE-27H G13.18.6.3-006 Rev 0 RIVER BEND STATION Undervoltage Relays Attachment 1 Outliers & Summary Page 8 of19 Extreme Final Drift Drift Cal Interval Cal Interval Seq. ID Tag ID Studentized Data Set (VAC) (Days) (Days)

Deviate (T) (VAC) 73 ENS-SWG1B-27-1B (UV) -0.03 560 0.302 -0.03 560 75 ENS-SWG1B-27-1B (UV) -0.03 330 0.302 -0.03 330 77 ENS-SWG1B-27-1B (UV) 0.12 573 0.616 0.12 573 81 ENS-SWG1B-27-1C (UV) 0.02 643 0.004 0.02 643 83 ENS-SWG1B-27-1C (UV) 0.08 545 0.372 0.08 545 85 ENS-SWG1B-27-1C (UV) -0.10 591 0.730 -0.10 591 87 ENS-SWG1B-27-1C (UV) 0.08 530 0.372 0.08 530 89 ENS-SWG1B-27-1C (UV) -0.12 560 0.852 -0.12 560 91 ENS-SWG1B-27-1C (UV) 0.11 330 0.555 0.11 330 93 ENS-SWG1B-27-1C (UV) 0.13 573 0.678 0.13 573

DRIFT ANALYSIS ABB/ITE-27H G13.18.6.3-006 Rev 0 RIVER BEND STATION Undervoltage Relays Attachment 1 W Test Page 9 of19 Drift bi (Per Values "i" an-i+1*

Step 4)

-0.40 1 0.3940 0.2758 Specific W Normality Test Methodology from Reference 4.1.7 and Section 19 of Reference 4.1.4

-0.20 2 0.2719 0.1088

-0.19 3 0.2357 0.0778 Steps to Perform:

-0.12 4 0.2091 0.0523 1. Paste all final drift data into column 1.

-0.10 5 0.1876 0.0413 2. Sort in ascending order.

2

-0.10 6 0.1693 0.0372 3. Calculate S taking the variance of the drift data adjusted by (Count-1)

-0.10 7 0.1531 0.0337

-0.10 8 0.1384 0.0291 S2 = (n-1)(Variance (Drift))

-0.10 9 0.1249 0.0262

-0.09 10 0.1123 0.0213 where: n = Count

-0.08 11 0.1004 0.0171

-0.03 12 0.0891 0.0098 4. Calculate the Quantity b:

-0.03 13 0.0782 0.0086

-0.03 14 0.0677 0.0074 b = Sum[(an-i+1)(xn-i+1 - xi)]

-0.03 15 0.0575 0.0034

-0.02 16 0.0476 0.0019 where: i = 1 to k

-0.02 17 0.0379 0.0008 k = (n-1)/2 0.00 18 0.0283 0.0000 xi = Drift value at point number i 0.00 19 0.0188 0.0000 an-i+1 values are taken from Table 1 of Reference 4.1.7.

2 0.00 20 0.0094 0.0000 5. Calculate b .

0.00 6. Compute the W Statistic and compare to the critical value at the 5% confidence 0.00 b= 0.7525 level. The table of critical values is given as Table 2 on page 9 of Reference 4.1.7.

0.00 (Per Step 4) 2 2 0.00

• From Table 1 of Ref. 4.1.7. W = b /S Results:

0.00 Since the W statistic, 0.9569, is greater than the 0.02 Computed Values critical value for W, 0.9410, this test does not 0.03 S2 = 0.5917 reject the assumption of normality for this data set.

0.08 b= 0.7525 0.08 b2 = 0.5662 0.08 Count (n): 41 0.09 W = b2/S2 = 0.9569 0.10 W Critical = 0.9410 5% Significance From Table 2 of Reference 4.1.7.

0.11 0.11 0.12 0.12 0.12 0.13 0.14 0.20 0.30

DRIFT ANALYSIS ABB/ITE-27H G13.18.6.3-006 Rev 0 RIVER BEND STATION Undervoltage Relays Attachment 1 Histogram Page 10 of19 Normal Cumulative Expected Bin No. StDev Bin Maximums = Observed Distribution Bin Descriptions Probability (CPi) Frequency No. (NS) Mean + (NS*StDev) Frequency Probability (Table 18-2 Ref 4.1.4) (Ei = Pnorm*N)

(Pnorm = CPi-CPi-1) 1 Up to - 2.5 Standard Deviations from Mean -2.5 -0.3019 1 0.0062 0.0062 0.2542 2 -2.5 to -2.0 Standard Deviations from Mean -2.0 -0.2411 0 0.0228 0.0166 0.6786 3 -2.0 to -1.5 Standard Deviations from Mean -1.5 -0.1802 2 0.0668 0.0441 1.8061 4 -1.5 to -1.0 Standard Deviations from Mean -1.0 -0.1194 1 0.1587 0.0919 3.7659 5 -1.0 to -0.5 Standard Deviations from Mean -0.5 -0.0586 7 0.3086 0.1499 6.1459 6 -0.5 Standard Deviations from Mean to Mean 0.0 0.0022 14 0.5000 0.1915 7.8495 7 Mean to +0.5 Standard Deviations from Mean 0.5 0.0630 2 0.6915 0.1915 7.8495 8 +0.5 to +1.0 Standard Deviations from Mean 1.0 0.1238 10 0.8414 0.1499 6.1459 9 +1.0 to +1.5 Standard Deviations from Mean 1.5 0.1846 2 0.9332 0.0919 3.7659 10 +1.5 to +2.0 Standard Deviations from Mean 2.0 0.2454 1 0.9773 0.0441 1.8061 11 +2.0 to +2.5 Standard Deviations from Mean 2.5 0.3063 1 0.9938 0.0166 0.6786 12 More than Mean + 2.5 Standard Deviations More More 0 1.0000 0.0062 0.2542 Totals 41 41 Percentage for Observed Observed

+/- Sigma Bounds Normal Drift Values Percentages Distribution 2.5 (Bins 2-11) 40 97.56% Mean 0.0022 2 (Bins 3-10) 39 95.12% 95.45% Std. Dev. 0.1216 1.5 (Bins 4-9) 36 87.80% Sample Size 41 1 (Bins 5-8) 33 80.49% 68.27%

0.5 (Bins 6-7) 16 39.02%

Methodology for Histogram Taken from Section 19 of Reference 4.1.4 and Section 3.7.5 of Reference 4.1.3

1. Order the drift data in ascending order.

2. Obtain mean, standard deviation, and sample size.

3. Establishing bins in 1/2 sigma increments from the mean to 2.5 sigma in both directions, derive the upper bin limits, in units of drift, based on the values of the mean and standard deviation.

4. Obtain expected frequency for a normal distribution in each bin.

5. Manually compute the number of observed drift data points within each bin, and list under observed frequency.

6. Plot the Expected Frequency and the Observed Frequency Data on the Histogram for comparison to each other.

Results: Since the data passed the W Test for normality, a Coverage Analysis is not necessary. The Histogram shows that the data conforms closely to a normal distribution.

DRIFT ANALYSIS ABB/ITE-27H G13.18.6.3-006 Rev 0 RIVER BEND STATION Undervoltage Relays Attachment 1 Histogram Page 11 of19 Histogram of Drift - River Bend Station ABB/ITE-27H Undervoltage Relays 16 14 Observed Frequency 12 Normal Distribution 10 Population 8

6 4

2 0

-0.3019 -0.2411 -0.1802 -0.1194 -0.0586 0.0022 0.0630 0.1238 0.1846 0.2454 0.3063 More Drift (VAC)

DRIFT ANALYSIS ABB/ITE-27H G13.18.6.3-006 Rev 0 RIVER BEND STATION Undervoltage Relays Attachment 1 Scatter Plot Page 12 of19 Scatter Plot - River Bend Station ABB/ITE-27H Undervoltage Relays 0.4 y = 0.0003x - 0.1415 0.3 Linear (Drift) 0.2 0.1 Drift (VAC C) 0 0 0.0

-0.1

-0.2

-0.3

-0.4

-0.5 0 100 200 300 400 500 600 700 Time (Days)

Note: Equation on Scatter Plot is computer generated, based on the associated trend line.

DRIFT ANALYSIS ABB/ITE-27H G13.18.6.3-006 Rev 0 RIVER BEND STATION Undervoltage Relays Attachment 1 Binning Analysis Page 13 of19 Bin Statistics Bin 1 Bin 2 Bin 3 Bin 4 Bin 5 Bin 6 Bin 7 Count 6 35 Standard Dev. 0.0809 0.1272 Mean -0.0333 0.0083 Mean Interval 327.00 574.66 Max Interval 330 650 Bin Definition and Selection Bin Hi Valid Limit Bin Population Bins Bins (Days) Count Percentage Included 1 45 0 0.0%

2 135 0 0.0%

3 230 0 0.0%

4 460 6 14.6% 4 5 690 35 85.4% 5 6 915 0 0.0%

7 Over 0 0.0%

Total Count: 41 100%

See Section 3.8.3 of Reference 4.1.3 for Binning Analysis Methodology.

DRIFT ANALYSIS ABB/ITE-27H G13.18.6.3-006 Rev 0 RIVER BEND STATION Undervoltage Relays Attachment 1 Binning Analysis Page 14 of19 Graph Summary Bin Time Std Dev Mean 4 327.00 0.0809 -0.0333 Binning Analysis - River Bend Station 5 574.66 0.1272 0.0083 ABB/ITE-27H Undervoltage Relays 0.14 Test of Variances 0.12 F Critical 4.481 0.10 Variance Ratio 2.471 0.08 Potential Strong TD of Drift (VAC)

Random Drift?

No 0.06 0 06 Std Dev 0.04 Mean 0.02 0.00

-0.02

-0.04

-0.06 0 200 400 600 800 Time (Days)

DRIFT ANALYSIS ABB/ITE-27H G13.18.6.3-006 Rev 0 RIVER BEND STATION Undervoltage Relays Attachment 1 Regression - Drift Page 15 of19 Regression Analysis - Drift REGRESSION ANALYSIS F Critical

SUMMARY

OUTPUT 3.238096 Regression Statistics Multiple R 0.207060 R Square 0.042874 Adjusted R Square 0.018332 Standard Error 0.120505 Observations 41 ANOVA df SS MS F Significance F Regression 1 0.0253686 0.0253686 1.746985 0.193957 Residual 39 0.5663338 0.0145214 Total 40 0.5917024 Coefficients Standard Error t Stat P-value Lower 95% Upper 95% Lower 95.0% Upper 95.0%

Intercept -0.141518 0.110347 -1.282478 0.207245 -0.364716 0.081680 -0.364716 0.0816803 X Variable 1 0.000267 0.000202 1.321736 0.193957 -0.000142 0.000675 -0.000142 0.0006754 Refer to Section 3.8.4 of Reference 4.1.3 for Methodology for Regression Analysis.

DRIFT ANALYSIS ABB/ITE-27H G13.18.6.3-006 Rev 0 RIVER BEND STATION Undervoltage Relays Attachment 1 Regression - Drift Page 16 of19 Drift Regression Line Fit Plot 0.4 0.3 0.2 Drift (VAC) 0.1 0.0 Drift 01

-0.1 Predicted Drift

-0.2

-0.3

-0.4

-0.5 0 200 400 600 800 Time (Days)

DRIFT ANALYSIS ABB/ITE-27H G13.18.6.3-006 Rev 0 RIVER BEND STATION Undervoltage Relays Attachment 1 Regression - AV of Drift Page 17 of19 Regression Analysis - AV of Drift ABSOLUTE VALUE REGRESSION ANALYSIS F Critical

SUMMARY

OUTPUT 3.238096 Regression Statistics Multiple R 0.154072 R Square 0.023738 Adjusted R Square -0.001294 Standard Error 0.083877 Observations 41 ANOVA df SS MS F Significance F Regression 1 0.0066715 0.0066715 0.948294 0.336156 Residual 39 0.2743772 0.0070353 Total 40 0.2810488 Coefficients Standard Error t Stat P-value Lower 95% Upper 95% Lower 95.0% Upper 95.0%

Intercept 0.013374 0.076807 0.174131 0.862663 -0.141982 0.168730 -0.141982 0.168730 X Variable 1 0.000137 0.000141 0.973804 0.336156 -0.000147 0.000421 -0.000147 0.000421 Refer to Section 3.8.4 of Reference 4.1.3 for Methodology for Regression Analysis.

DRIFT ANALYSIS ABB/ITE-27H G13.18.6.3-006 Rev 0 RIVER BEND STATION Undervoltage Relays Attachment 1 Regression - AV of Drift Page 18 of19 AV of Drift Regression Line Fit Plot 0.45 0.40 AV of Drifft (VAC) 0.35 0.30 0.25 AV of Drift 0.20 Predicted AV of Drift 0.15 0.10 0.05 0.00 0 200 400 600 800 Time (Days)

DRIFT ANALYSIS ABB/ITE-27H G13.18.6.3-006 Rev 0 RIVER BEND STATION Undervoltage Relays Attachment 1 Analyzed Drift (DA) Page 19 of19 Drift Bias Determination First, the bias term is evaluated for significance per Section 3.10 of Reference 4.1.3.

Per Outlier Statistical Summary, Count (N) 41 Drift Data Points Drift Bias Term (Mean) 0.0022 VAC Standard Deviation (Stdev)) 0.1216 VAC t for Count = 41 Data Points 2.000 (Ref. 4.1.3, Table 4)

[Bias (Crit) = t

• Stdev / (N)^0.5]

Signficant Bias Critical Value 0.038 VAC Therefore, the bias value for this drift data set is not signficant, since the magnitude of the Bias is less than the Critical Bias Value.

DAbias = Negligible R d Random D ift Determination Drift D t i ti Time Dependency Moderate Count (N) 41 Drift Data Points Bin 5 Standard Deviation (Stdev) 0.1272 VAC Mean Bin 5 Time Interval 575 Days Maximum Required Cal Interval 915 Days Tolerance Interval Factor (TIF) 2.445 (Ref. 4.1.3, Table 1)

[Current Interval Drift = Stdev

• TIF]

DArandom (current) = +/- 0.311 VAC

[Extrap Drift = DArandom (current) * (Required Cal Interval / Mean Bin 5 Cal Interval)1/2]

DArandom (extrap) = +/- 0.392 VAC for up to 915 Days

G13.18.6.3-006 Attachment 2 Page 1 of 8 DESIGN VERIFICATION COVER PAGE ANO-1 ANO-2 IP-2 IP-3 JAF PLP PNPS VY GGNS RBS W3 NP Document No. G13.18.6.3-006 Revision No. Page 1 of 0

Title:

Drift Study for ABB Model ITE-27H Undervoltage Relays Quality Related Augmented Quality Related DV Method: Design Review Alternate Calculation Qualification Testing VERIFICATION REQUIRED DISCIPLINE VERIFICATION COMPLETE AND COMMENTS RESOLVED (DV print, sign, and date)

Electrical Mechanical Richard J. Hannigan Instrument and Control 1-20-09 Civil/Structural Nuclear Originator:

R.A. Hunter 1-20-09 Print/Sign/Date After Comments Have Been Resolved

G13.18.6.3-006 Attachment 2 Page 2 of 8 DESIGN VERIFICATION CHECKLIST SHEET 1 OF 3 IDENTIFICATION: DISCIPLINE:

Civil/Structural Document

Title:

Drift Study for ABB Model ITE-27H Undervoltage Electrical Relays Doc. No.:G13.18.6.3-006 Rev. 0 QA Cat. 1 I&C Mechanical Nuclear Richard J. Hannigan 1-20-09 Verifier: Print Sign Date Other Manager authorization for supervisor performing Verification.

N/A Print Sign Date METHOD OF VERIFICATION:

Design Review Alternate Calculations Qualification Test The following basic questions are addressed as applicable, during the performance of any design verification. These questions are based on the requirements of ANSI N45.2.11 - 1974.

NOTE The reviewer can use the Comments/Continuation sheet at the end for entering any comment/resolution along with the appropriate question number. Additional items with new question numbers can also be entered.

1. Design Inputs - Were the inputs correctly selected and incorporated into the design?

(Design inputs include design bases, plant operational conditions, performance requirements, regulatory requirements and commitments, codes, standards, field data, etc.

All information used as design inputs should have been reviewed and approved by the responsible design organization, as applicable.

All inputs need to be retrievable or excerpts of documents used should be attached.

See site specific design input procedures for guidance in identifying inputs.)

Yes No N/A

2. Assumptions - Are assumptions necessary to perform the design activity adequately described and reasonable? Where necessary, are assumptions identified for subsequent re-verification when the detailed activities are completed? Are the latest applicable revisions of design documents utilized?

Yes No N/A

3. Quality Assurance - Are the appropriate quality and quality assurance requirements specified?

Yes No N/A

G13.18.6.3-006 Attachment 2 Page 3 of 8 DESIGN VERIFICATION CHECKLIST SHEET 2 OF 3

4. Codes, Standards and Regulatory Requirements - Are the applicable codes, standards and regulatory requirements, including issue and addenda properly identified and are their requirements for design met?

Yes No N/A

5. Construction and Operating Experience - Have applicable construction and operating experience been considered?

Yes No N/A

6. Interfaces - Have the design interface requirements been satisfied and documented?

Yes No N/A

7. Methods - Was an appropriate design or analytical (for calculations) method used?

Yes No N/A

8. Design Outputs - Is the output reasonable compared to the inputs?

Yes No N/A

9. Parts, Equipment and Processes - Are the specified parts, equipment, and processes suitable for the required application?

Yes No N/A

10. Materials Compatibility - Are the specified materials compatible with each other and the design environmental conditions to which the material will be exposed?

Yes No N/A

11. Maintenance requirements - Have adequate maintenance features and requirements been specified?

Yes No N/A

12. Accessibility for Maintenance - Are accessibility and other design provisions adequate for performance of needed maintenance and repair?

Yes No N/A

13. Accessibility for In-service Inspection - Has adequate accessibility been provided to perform the in-service inspection expected to be required during the plant life?

Yes No N/A

14. Radiation Exposure - Has the design properly considered radiation exposure to the public and plant personnel?

Yes No N/A

15. Acceptance Criteria - Are the acceptance criteria incorporated in the design documents sufficient to allow verification that design requirements have been satisfactorily accomplished?

Yes No N/A

16. Test Requirements - Have adequate pre-operational and subsequent periodic test requirements been appropriately specified?

Yes No N/A

G13.18.6.3-006 Attachment 2 Page 4 of 8 DESIGN VERIFICATION CHECKLIST SHEET 3 OF 3

17. Handling, Storage, Cleaning and Shipping - Are adequate handling, storage, cleaning and shipping requirements specified?

Yes No N/A

18. Identification Requirements - Are adequate identification requirements specified?

Yes No N/A

19. Records and Documentation - Are requirements for record preparation, review, approval, retention, etc., adequately specified? Are all documents prepared in a clear legible manner suitable for microfilming and/or other documentation storage method? Have all impacted documents been identified for update as necessary?

Yes No N/A

20. Software Quality Assurance- ENN sites: For a calculation that utilized software applications (e.g., GOTHIC, SYMCORD), was it properly verified and validated in accordance with EN- IT-104 or previous site SQA Program?

ENS sites: This is an EN-IT-104 task. However, per ENS-DC-126, for exempt software, was it verified in the calculation?

Yes No N/A

21. Has adverse impact on peripheral components and systems, outside the boundary of the document being verified, been considered?

Yes No N/A

G13.18.6.3-006 Attachment 2 Page 5 of 8 DESIGN VERIFICATION COMMENT SHEET SHEET 1 OF 1 Comments / Continuation Sheet Question Comments Resolution Initial/Date NONE

G13.18.6.3-006 Attachment 2 Page 6 of 8 During the independent review of calculation G13.18.6.3-006, alternate applications Lotus 1-2-3 and Quattro Pro were used to validate the results generated by MS Excel in the calculation. The reviewer independently generated the G13.18.6.3-006 results. In the table below the results of the validation for the G13.18.6.3-006 values and the values produced by Lotus 1-2-3 and Quattro Pro are illustrated for the Final Data Set - after removal of the single outlier. The results from Lotus 1-2-3 and Quattro Pro validated the calculation G13.18.6.3-006 results generated by MS Excel. Minor differences in the values between the MS Excel generated results and the Lotus 1-2-3 and Quattro Pro generated results were reviewed and can be attributed to rounding and conversion between applications. Below is a partial listing of some of the values from G13.18.6.3-006 that were validated:

Validation Parameter G13.18.6.3-006 value Validation value application Valid?

Mean 0.0022 0.0022 Lotus 1-2-3 Yes Variance 0.0148 0.0148 Lotus 1-2-3 Yes Standard 0.1216 0.1216 Lotus 1-2-3 Yes Deviation Count 41 41 Lotus 1-2-3 Yes Max 0.30 0.30 Lotus 1-2-3 Yes Median 0.00 0.00 Lotus 1-2-3 Yes Min -0.40 -0.40 Lotus 1-2-3 Yes Range 0.70 0.70 Lotus 1-2-3 Yes Sum 0.090 0.090 Lotus 1-2-3 Yes Kurtosis 2.234 2.234 Lotus 1-2-3 Yes Skewness -0.581 -0.581 Lotus 1-2-3 Yes Outliers Sequ. ID 17 identified Sequ. ID 17 identified Lotus 1-2-3 Yes as an outlier and as an outlier and removed removed Visual inspection Drift scatter plot N/A shows agreement Lotus 1-2-3 Yes with trend line between the scatter plots and trend lines Drift scatter plot trend line Y = 0.0003x - 0.1415 Y = 0.000267x - 0.142 Lotus 1-2-3 Yes W Test Value 0.9569 (does not reject 0.9569 (does not reject Lotus 1-2-3 Yes assumption of assumption of normality) normality)

Visual inspection Histogram N/A shows agreement Lotus 1-2-3 Yes between the histograms

G13.18.6.3-006 Attachment 2 Page 7 of 8 Validation Parameter G13.18.6.3-006 Validation value application Valid?

value Data within 0.5 Standard Deviations 16 16 Lotus 1-2-3 Yes Data within 1.0 Standard Deviation 33 33 Lotus 1-2-3 Yes Data within 1.5 Standard Deviations 36 36 Lotus 1-2-3 Yes Data within 2.0 Standard Deviations 39 39 Lotus 1-2-3 Yes Data within 2.5 Standard Deviations 40 40 Lotus 1-2-3 Yes Bin 4 count 6 6 Lotus 1-2-3 Yes Bin 4 drift Standard Deviation 0.0809 0.0809 Lotus 1-2-3 Yes Bin 4 drift mean -0.0333 -0.0333 Lotus 1-2-3 Yes Bin 4 interval mean 327.00 327.00 Lotus 1-2-3 Yes Bin 4 interval 330 330 Lotus 1-2-3 Yes maximum Bin 5 count 35 35 Lotus 1-2-3 Yes Bin 5 drift Standard Deviation 0.1272 0.1272 Lotus 1-2-3 Yes Bin 5 drift mean 0.0083 0.0083 Lotus 1-2-3 Yes Bin 5 interval mean 574.66 574.66 Lotus 1-2-3 Yes Bin 5 interval 650 650 Lotus 1-2-3 Yes maximum Binning Analysis 2.471 2.471 Lotus 1-2-3 Yes Ratio of Variances Binning Analysis 4.481 4.481 Quattro Pro Yes F Critical Visual inspection Drift Regression NA shows agreement Lotus 1-2-3 Yes Scatter Plot between the two scatter plots and trend lines.

Drift Regression Scatter Plot Trend Y = 0.000267x Y = 0.000267x Quattro Pro Yes Line -0.141518 -0.141518 Drift Regression R Square Value 0.042874 0.042874 Quattro Pro Yes Drift Regression Yes F Value 1.746985 1.746985 Quattro Pro F Crit Value 3.238096 3.238096 Quattro Pro Yes Drift Regression P-Value 0.193957 0.193766 Quattro Pro Yes

G13.18.6.3-006 Attachment 2 Page 8 of 8 Validation Parameter G13.18.6.3-006 Validation value application Valid?

value Visual inspection AV Drift Regression NA shows agreement Lotus 1-2-3 Yes Scatter Plot between the two scatter plots and trend lines.

AV Drift Regression Y = 0.000137x Y = 0.000137x Scatter Plot Trend +0.013374 +0.013374 Quattro Pro Yes Line AV Drift Regression R Square Value 0.023738 0.023738 Quattro Pro Yes AV Drift Regression F Value 0.948294 0.948294 Quattro Pro Yes F Crit Value 3.238096 3.238096 Quattro Pro Yes AV Drift Regression P-Value 0.336156 0.336006 Quattro Pro Yes Other values, including those based on the above parameters, were checked using hand calculations.