ML20034B785

Rev 4 to Westinghouse Setpoint Methodology for Protection Sys,Sequoyah Units 1 & 2 Eagle-21 Version

ML20034B785
Person / Time
Site:	Sequoyah
Issue date:	02/28/1990
From:	Tuley C WESTINGHOUSE ELECTRIC COMPANY, DIV OF CBS CORP.
To:
Shared Package
ML19302E069	List: ML20034B782 ML20034B783 ML20034B785
References
WCAP-11626, WCAP-11626-R04, WCAP-11626-R4, NUDOCS 9005010007
Download: ML20034B785 (85)

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{{#Wiki_filter:. WESTINGHOUSE CLASS 3 ' !{ WCAP 11626~- l Rev.4' 'i 3 .e en l-l- t -. WESTINGH USE SETPOINT METHODOLOGY FOR PROTECTION SYSTEMS i SEQUOYAH UNITS 1 AND 2 EAGLE-21 VERSION 1 f February,1990 i ( ( C. R. Tuley l l l. l l ^ WESTINGHOUSE ELECTRIC Energy Systems lc P. O. Box 355 Pittsburgh, Pennsylvania.'15230 !+ i e 1990 Westinghouse Electric Corporation 9005010057 900423 PDR ADOCK 05000327 P PDC D0161:1D/022690 i

a WESTINGHOUSE CLASS 3' l TABLE OF CONTENTS l ,{ Section Title Page

1.0 INTRODUCTION

1-1 2.0 COMBINATION OF ERROR COMPONENTS 2-1 l 2.1 Methodology-2-1 2.2 Sensor Allowances 23 s 2.3 Rack Allowances 2 2.4 Process Allowances 2 l 2.5 Measurement and Test Equipment Accuracy 2-6 3.0 PROTECTION SYSTEMS SETPOINT METHODOLOGY-3-1. 3.1 Margin Calculation 3-1 3.2 Definitions for Protection System 3-1 Setpoint Tolerances l 3.3 Statistical Metho'dology Conclusion. 3-6 4.0 TECHNICAL SPECIFICATION USAGE 4-1 4.1 Current Use-4-1 4.2 Westinghouse Setpoint . 4-1 Methodology for STS Setpoints l 4.2.1 Rack Allowance 4-2 4.2.2 Inclusion of "As Measured" 43 l Sensor Allowance 4.2.3 Implementation of the 4-4 Westinghouse Setpoint Methodology 4.3 Conclusion 46 l-Appendix A SAMPLE SEQUOYAH SETPOINT TECHNICAL A-1 L' SPECIFICATIONS D0161:10/022690 ii

WESTINGHOUSE CLASS 3 i LIST OF TABLES Table Title Page 3-1 Power Range, Neutron Flux High and Low Setpoints 3-7 o 32 Power Range, Neutron Flux High Positive Rate and 38 High Negative Rate 33 Intermediate Range, Neutron Flux 39 3-4 Source Range, Neutron Flux. 3 ' 35 Overtemperature AT 3 11 3-6 Overpower AT 3-13 3-7 Pressurizer Pressure Low and High, Reactor Trips 3-15 3-8 Pressurizer Water Level - High '3 16 3-9 Loss of Flow 3-17 3 10 Steam Generator Water Level - Low Low Adverse 3-18 j l & EAM (Unmodified Barton) 3-11 Steam Generator Water Level-Low Low Adverse 3-19' & EAM (Modified Barton) 3 12 Containment Pressure - High, EAM and High-High 3 20 (Foxboro) 3 13 Containment Pressure - High, EAM and High High 3 21 (Barton) 3-14 Pressurizer Pressure - Low, Safety injection 3 22 3-15 Steamline Pressure - Low 3 23 3 16 Negative Steamline Pressure Rate - High 3-24 3-17 Steam Generator Water Level - High-High 3-25 3-18 RWST Level - Low and High 3-26 I 3-19 RCP - Underfrequency (W SDF-2) 3-27 3-20 RCP - Undervoltage (GE NGV-13) 3-28 3 21 Vessel AT Equivalent to Power 3-29 3 22 Reactor Protection System / Engineered Safety Features 3-31 Actuation System Channel Error Allowances 3 23 Overtemperature AT Gain Calculations 3-32 9 3-24 Overpower AT Gain Calculations 3-34 D0161:10 022690 iii

WESTINGHOUSE CLASS 3 LIST OF TABLES Table Title Page t 3 25 Steam Generator Level Density Variations 3-35 3 26 AP Measurements Expressed in Flow Units 3 36 -l 4 Examples of Current STS Setpoints Philosophy 49 4-2 Examples of Westinghous~ STS Rack Allowance 49 e 4-3 Westinghouse Protection System STS Setpoint inputs 4-13 -] 'I l i .l i 5 i l d i a s a 00161:1D/022690 iV J

WESTINGHOUSE CLASS 3 LIST OF ILLUSTRATIONS Figure Title Page 4-1 NUREG 0452 Rev. 4 Setpoint Error 4-10 Breakdown. 4-2 Westinghouse STS Setpoint Error 4 11 Breakdown - Analog Process Racks 4-3 Westinghouse STS Setpoint Error 4-12 Breakdown - Digital Process Racks ) i

• 1 h

4 ! e i 00161:10/022690 y l I l

e WESTINGHOUSE CLASS 3 '1

1.0 INTRODUCTION

In March of 1977, the NRC requested several utilities with Westinghouse Nuclear 5 i' Steam Supply Systems to reply to a series of questions concerning the methodology I-[. for determining instrument setpoints. A revised methodology was developed in response to those questions with a corresponding defense of the technique used in I determining the overall allowance for each setpoint. The basic underlying assumption used is that several of the error components and' their parameter assumptions act independently, e.g., rack versus sensors and ~ i pressure / temperature assumptions. This allows the use of a statistical summation of the various breakdown components instead of a-strictly arithmetic summation. A 3 direct benefit of the use of this technique is increased margin in.the total allowance. For those parameter assumptions known to be interactive, the technique uses the standard, conservative approach, arithmetic summation, to form independent quantities, e.g., drift and calibration error. An explanation of the overall approach is provided in Section 2.0. Section 3.0 provides a description, or definition, of each of the various components in the setpoint parameter breakdown, to allow a clear understanding c' the' breakdown. Also provided is a detailed example of each setpoint uncertainty - calculation demonstrating the technique and noting how each parameter value is derived. In all cases, sufficient margin exists between the summation and the total allowance. 7 Section 4.0 notes what the current standardized Technical Specifications use for setpoints and an explanation of the impact of the Westinghouse approach on them. Detailed examples of how to determine the Technical Specification setpoint values are also provided. An Appendix is provided noting a recommended set of Technical ~ Specifications using the plant specific data and Eagle-21 process rack errors in the Westinghouse approach. l 00161:1D:022690 1-1

>[ WESTINGHOUSE. CLASS 3 [ r 7 2.0 COMBINATION OF ERROR COMPONENTS 2.1 METHODOLOGY } The methodology used to combine the error components for a channel is basically the appropriate combination of those groups of components which are statistically ~ independent, i.e., not interactive. Those errors which are not independent are placed arithmetically into groups. The groups themselves are independent effects which can then be systematically combined, The methodology used for.this combination is the " square root of the sum of the squares" which has been utilized in other Westinghouse reports, This technique, or other approaches of a similar nature, have been used in WCAP 10395N and WCAP. 8567<21 WCAP 8567 has been approved by the NRC Staff thus noting the acceptability of statistical techniques for the application requested, in addition, various ANSI, American Nuclear Society, and Instrument Society of America standards approve of the use of probabilistic and statistical techniques in determining safety related setpoints*W The methodology used in this report is. essentially the same as that used for V, C, Summer, which was approved in NUREG-0717, Supplement No. 4W, The relationship between the error components and the total error allowance for a channelis noted in Equation 2,1 l CSA = EA + {(PMA)2 + (PEA)2 + (SCA + SMTE + SD)2 + (SPE)2 +(STE)2 + (RCA + RMTE + RCSA + RD)2 + (RTE)2}v2 (Eq. 2,1) l l* (1) Gngsby, J M, Spier E. M., Tuley, C. R., " Statistical Evaluation of LoCA Heat Source Uncertainty," WCAP 10395 (Propnetary), WCAP 10396 (Non-Proprietary) November,1983. (2) Chelemer, H., Boman, L. H., and Sharp, D, R., " Improved Thermal Design Procedure," WCAP-8567 -e (Propnetary), WCAP 8568 (Non-Proprietary), July,1975. (3) ANSI /ANS Standard 58.41979, "Cntena for Technical specifications for Nuclear Power stations." (4) ISA standard s67.04,1987, "Setpoints for Nuclear Safety Related Instrumentation Used in Nuclear Power Plants." (5) NuREG-0717, Supplement No. 4. " safety Evaluation Report related to the operation of Virgil C. Summer Nuclear station, unit No.1," Docket No. 50-395, August 1982. D0161:1D/022690 2-1

,l WESTINGHOUSE CLASS 3 where: CSA = Channel Statistical Allowance .} EA = Environmental Allowance PMA =- Process Measurement Accuracy l PEA = Primary Element Accuracy SCA = Sensor Calibration Accuracy SMTE = Sensor Measurement and Test Equipment Accuracy SD = Sensor Drift SPE = Sensor Pressure Effects STE = Sensor Temperature Effects f RCA = Rack Calibration Accuracy RMTE = Rack Measurement and Test Equipment Accuracy RCSA = Rack Comparator Setting Accuracy RD = Rack Drift RTE = Rack Temperature Effects This equation was originally designed to address analog process racks with bistables. Digital process racks generally operate in a different manner by simulating a bistable. The protection function setpoint is a value held in memory. A trip is initiated when the input to the calculation is compared to and corresponds to the value in memory. Thus, with absence of a physical bistable, the RCSA term can be redefined. Depending on the function, the RMTE term can also be redefined. The calculations for the protection functions noted in this document reflect the use of either analog or digital process racks (whichever is appropriate) and the corresponsding values for RCSA and RMTE as required. As can be seen in Equation 2.1, drift and calibration accuracy allowances are interactive and thus not independent. The environmental allowanee is not necessarily considered interactive with all other parameters, but as an additional degree of conservatism is added to the statistical sum. It should be noted that for this document it was assumed that the accuracy effect on a channel due to cable degradation in an accident environment will be less than 0.1 percent of span. This impact has been considered negligible and is not factored into the analysis. An error due to this cause found to be in excess of 0.1 percent of span must be directly added as an environmental error. Several functions were identified by TVA as D0161:1D 022690 2-2 l

WESTINGHOUSE CLASS 3 having cable IR errors in excess of 0.1 percent span. These errors were incorporeted into the calculations, t + The Westinghouse setpoint methodology results in a value with a 95 percent i probability with a high confidence level. With the exception of Process Measurement Accuracy, Rack Drift, and Sensor Drift, all uncertainties assumed are the extremes of the ranges of the various parameters, i.e., are better than 20 values. Analog Rack Drift and Sensor Drift are assumed, based on a survey of reported plant LERs, digital Rack Drift is based on system design, and with Process Measurement Accuracy are considered as conservative values. t L 2.2 SENSOR ALLOWANCES Five parameters are consiEered to be sensor allowances,- SCA, SMTE, SD, STE, and SPE (see Table 3 22)..Of these parameters, two are considered to be statistically independent, STE and SPE, and three are considered interactive SCA, SMTE and SD. STE and SPE are considered to be independent due to the manner ' 3, in which the instrumentation is checked, i.e., the instrumentation is calibrated and drift determined under conditions in which pressure and temperature are assumed constant. An example of this would be as follows; assume a sensor.is placed in some position in the containment during a refueling outage. After placement, an instrument technician calibrates the sensor. This calibration is performed at ambient pressure and temperature conditions. Some time later with the plant shutdown, an i instrument technician checks for sensor drift. Using the same technique as for calibrating the sensor, the technician determines if the sensor has drifted or not. The conditions under which this determination is made are again at ambient pressure and temperature conditions. Thus the temperature and pressure have no impact on the drift determination and are, therefore, independent of the drift-I allowance. l SCA, SMTE and SD are considered to be interactive for the same reason that STE and SPE are considered independent, i.e., due to the manner in which the instrumentation is checked. Instrumentation calibration techniques use the same process as determining instrument drift, that is, the end result of the two is the j same. When calibrating a sensor, the sensor output is c'hecked to determine if it is \\ accurately representing the input. The same is performed for a determination of the l D0161:10 022690 2-3

WESTINGHOUSE CLASS 3 i L sensor drift. Thus unless "as left-as found" data is recorded and used, it is impossible to determine the differences between calibration errors and' drift when a : sensor is checked the second or any subsequent time. Based on this reasoning, [ SCA SMTE and SD have been added to form an independent group which is then factored into Equation 2.1. An example of the impact of this treatment is; for [ l Pressurizer Water Level-High (sensor. parameters only): l [ _ + a,c SCA = SMTE = STE = SPE = SD = using Equation 2.1 as written gives a total of; { (SCA + SMTE + SD)2 + (STE)2 + (SPE)2 }u2 y [ ]+8* = 2.12% .+ Assuming no interactive effects for any of the parameters gives the following results: { (SCA)2 + (SMTE)2 + (SD)2 + (STE)2 + (SPE)2 yu2 (Eq. 2.2) 1.41 % l [ ]+** = Thus it can be seen that the approach represented by Equation 2.1 which accounts for interactive parameters results in a more conservative summation of the allowances. 2.3 RACK ALLOWANCES Five parameters, as noted by Table 3-22, are considered to be rack allowances, RCA, RMTE, RCSA, RTE, and RD. Four of these parameters are considered to be interactive (for much the same reason outlined for sensors in 2.2), RCA, RMTE, RCSA, and RD. When calibrating or determining drift in the racks for a specific channel, the processes are performed at essentially constant temperature, i.e., 00161:10 022690 2-4 s

WESTINGHOUSE CLASS 3 L ambient temperature. Because of this, the RTE parameter is considered to be independent of any factors for calibration or drift. However, the same cannot be said for the other rack parameters. As noted in 2.2, { when calibrating or determining drift for a channel, the same end result is desired, ~ that is, for an analog protection function, at what point does the bistable change state. After initial calibration, without recording and using "as left as found" data, it is not possible to distinguish the difference between a calibration error, rack drift or a comparator setting error. Based on this logic, these factors have been added to - form an independent group. This group is then factored into Equation 2.1. The impact of this approach (formation of an independent group based on interactive components) is significant. For the same channel using the same approach outlined: in Equationc 2.1 and 2.2 and using analog process rack uncertainties, the following l results are reached: } _ + a,c RCA = RMITE = RCSA = i RTE = RD = i using Equation 2.1 the result is; { (RCA + RMTE + RCSA + RD)2 + (RTE)2 }ii2 ( ]+** = 2.30% Assuming no interactive effects for any of the parameters yields the following less conservative results; { (RCA)2 + (RMTE)2 + (RCSA)2 + (RD)2 + (RTE)2 }t/2 (Eq. 2.3) l [ ]+'d = 1.35% Thus, the impact of the use of Equation 2.1 is even greater in the area of rack effects than for the sensor. Similar results, with different magnitudes, would be o0161:10/022690 2-5

WESTINGHOUSE CLASS 3 arrived at using digital process rack uncertainties. Therefore, accounting for interactive effects in the treatment of these allowances insures a conservative result. ,j 2.4 - PROCESS ALLOWANCES i Finally, the PMA and PEA parameters are considered to be independent of both 1 sensor and rack parameters. PMA provides allowances for the non-instrument' ] related effects, e.g., neutron flux, calorimetric power error assumptions, fluid density. changes, and temperature stratification assumptions. PMA may consist of more i than one independent error allowance. PEA accounts for errors due to metering ' j devices, such as elbows and venturis. Thus, these parameters have' been factored - into Equation 2.1 as independent quantities. 2.5 MEASUREMENT AND TEST EQUIPMENT ACCURACY Westinghouse was informed by Sequoyah that the equipment used for calibration. and functional testing of the transmitters and racks did not meet SAMA standard. PMC 20.1 1973(1) with regards to test equipment accuracy of 10 percent or less of .. ~ the calibration accuracy (referenced in 3.2.6.a or 3.2.7.a.) This then required'the inclusion of the accuracy of this equipment in equations 2.1 and 3.1. Based on information provided by the plant, these a' ditional uncertainties were included in the d calculations, as noted on the tables included in this report, with minor impact on the final results. On Table 3-22, the values for SMTE and RMTE are specifically - 4 identified. I l l .1 ~ -l (1) scientific Apparatus Manufacturers Association, standard PMC 20.1 1973. " Process Measurement and Control Terrninology " D0161:10 022690 2-6

'1 f WESTINGHOUSE CLASS 3 ^ 3.0 PROTECTION SYSTEM SETPOINT METHODOLOGY 3.1 MARGIN CALCULATION [ As noted in Section Two, Westinghouse utilizes the' square root of the sum of the _ l squares for summation of the various components of the channel breakdown. This approach is valid where no dependency is present. An arithmetic summation is: required 'where an interaction between two parameters exists. The equation used to determine the margin, and thus the acceptability of the parameter values used, is: Margin = (TA)-(EA + {(PM A)2 + (PEA)2 + (SCA + SMTE + SD)2 + (SPE)2 + (STE)2 +(RCA + RMTE + RCSA + RD)2 +(RTE)2 yu2) (Eq. 3.1_ ) where: TA = Total Allowance, and all other parameters are as defined for Equation 2.1. Again, please note that Eq. 3.1 is representative for a channel with analog process racks. Use of digital process racks results in deletion of the RCSA term. The magnitude of the RMTE term is typically different for digital process racks when ' 4 compared to typical values for analog process racks. l l Tables 3-1 through 3-21 provide individual channel breakdown and channel statistical allowance calculations for all protection functions, utilizing appropriate [ values for the process rack equipment. Table 3 22 provides a summary of the previous 21 tables and includes analysis and Technical Specification values, Total Allowance and Margin, i* ' 3.2 DEFINITIONS FOR PROTECTION SYSTEM SETPOINT TOLERANCES l' 1 To insure a clear understanding of the channel breakdown used in this report, the. following definitions are noted: 00161:10,022690 3-1

WESTINGHOUSE CLASS 3 1 1 1. Trip Accuracy The tolerance band containing the highest expected value of the difference between (a) the desired trip point value of a process variable and.(b) the actual value at which a trip is initiated (and thus actuates some desired result). This is the tolerance band, in percent of span, within which the complete ,) l channel must perform its intended trip function. It includes comparator setting. accuracy (for analog process racks), channel accuracy (including the sensor) for each input, and environmental effects on the rack mounted electronics, it ' comprises all instrumentation errors; however, it does not include process measurement accuracy. 2. Process Measurement Accuracy includes plant variable measurement errors up to but not including the sensor. Examples are the effect of fluid stratification on temperature measurements and the effect of changing fluid density on level measurements. 3. Actuation Accuracy Synonymous with trip accuracy, but used where the word " trip" does not apply. 4. Indication Accuracy The tolerance band containing the highest expected value of the difference between (a) the value of a process variable read on an indicator or recorder and (b) the actual value of that process variable. An indication must fall within = this tolerance band, it includes channel accuracy, accuracy of readout .j devices, and rack environmental effects, but not process measurement ,j accuracy such as fluid stratification. It also assumes a controlled environment j l for the readout device. t 5. Channel Accuracy 1 i The accuracy of an analog channel which includes the accuracy of the primary l element and/or transmitter and modules in the chain where calibration of D0161:10:022690 32

WESTINGHOUSE CLASS 3 modules intermediate in a chain is allowed to compensate for errors in other. modules of the chain. Rack environmental effects are not included here to [ avoid duplication due to dual inputs, however, normal environmental effects on field mounted hardware is included. a For a digital channel, it is the accuracy which includes the accuracy of the primary element and/or transmitter and the signal conditioning - A/D conversion modules. Since typically only.one module is present, compensation between multiple modules for errors is not possible. Compensation between multiple modules for errors is possible for protection functions with multiple inputs. I 6. Sensor Allowable Deviation -t The accuracy that can be expected in the field, it includes drift, tempsrature effects, field calibration and for the case of d/p transmitters, an allowance for the effect of static pressure variations. The tolerances are as follows: a. Reference (calibration) accuracy - [ ]+5c percent unless other data indicates more inaccuracy. This accuracy is the SAMA reference - accuracy as defined in SAMA standard PMC 20.1 1973N. b. Measurement and Test Equipment accuracy - usually included as an integral part of (a), Reference (calibration) accuracy, when less than 10 percent of the value of (a). For equipment (DVM, pressure gauge, etc.) used to calibrate the sensor with larger uncertainty values, a specific allowance is made. c. Temperature effect - [ )+ Ac percent based on a nominal temperature i coefficient of [ ]+ a,c percent /100*F and a maximum assumed change of 50'F. (1) Scientific Apparatus Manufacturers Association. standard PMC20.1-1973, " Process Measurement and Control Terminology." D0161:10 022690 3-3 t

WESTINGHOUSE CLASS 3 d. Pressure effect usually calibrated out because pressure is constant. If not constant, nominal [ }**c percent is used. Present data indicates a static pressure effect of approximately [ ]*a,e percent /1000 psl. e. Drift - change in input output relationship over a period of time at reference conditions (e.g., constant temperature - [ )*a.c percent of span), i 7. Rack Allowable Deviation f The tolerances are as follows: a. Rack Calibration Accuracy The accuracy that can be expected during a calibration at reference conditions. This accuracy is the SAMA reference accuracy as defined in SAMA standard PMC 20.1 1973m. For an analog channel this includes all modules in a rack and is a total of [ ]+a.o.c percent of span assuming the chain of modules is tuned to this accuracy. For simple loops where a power supply (not used as a converter) is the only rack module, this accuracy may be ignored. All analog process modules individually must have a reference accuracy within [ ]* a.b.c percent. For a digital channel, this accuracy represents calibration of the signal conditioning A/D converter providing input to the central processing unit. Each signal conditioning A/D converter module is calibrated to within an accuracy of [ ]**bc percent span (for functions with rack inputs of 10 50 mA), or [ )+8bc percent span (for functions with RTD rack inputs). b. Measurement and Test Equipment Accuracy usually included as an integral part of (a), Reference (calibration) accuracy, when less than 10 - .l percent of the value of (a). For equipment (DVM, current source, voltage source, etc.) used to calibrate the racks, either analog or digital, with larger uncertainty values, a specific allowance is made. l D0161:1D/022690 34 1

WESTINGHOUSE CLASS 3 c. Rack Environmental Effects includes effects of temperature, humidity, voltage and frequency changes of which temperature is the most significant. An accuracy of ( )

• a.o.c percent is used for analog racks, and [

)*a.o.e percent is used for digital racks, which considers a nominal ambient temperature of 70'F with extremes to 40'F and 120'F for short periods of time. d. Rack Drift (instrument channel drift) change in input output relationship over a period of time at reference conditions (e.g., constant temperature) - 11 percent of span for analog racks and [ )**c percent span for digital racks. e. Comparator Setting Accuracy For an analog channel, assuming an exact electronic input, (note that the " channel accuracy" takes care of deviations from this ideal), the tolerance on the precision with which a comparator trip value can be set, within such practical constraints as time and effort expended in making the setting. The tolerances assumed for Sequoyah (based on input from TVA) are as follows: (a) Fixed setpoint with a single input -[ )+a.o.e percent accuracy. This assumes that comparator nonlinearities are compensated by the setpoint. (b) Dualinput an additional ( )**bc percent must be added for comparator nonlinearities between two inputs. Total [ ]***c percent accuracy. Digital channels do not have an electronic comparator, therefore no uncertainty is included for this term for these channels. Note: The following four definitions are currently used in the Standardized Technical Specifications (STS). D0161:10'022690 35

WESTINGHOUSE CLASS 3 1 8. Nominal Safety System Setting The desired setpoint for the variable. Initial calibration and subsequent recalibrations should be made at the nominal safety system setting l (" Trip Setpoint" in STS). 9. Limiting Safety System Setting A setting chosen to prevent exceeding a Safety Analysis Limit (" Allowable Values" in STS) Violation of this setting may be an STS violation.

10. Allowance for Instrument Channel Drift The difference between (8) and (9) taken in the conservative direction.

11. Safety Analysis Limit The setpoint value assumed in the safety analyses.

12. Total Allowable Setpoint Deviation Maximum setpoint deviation from a nominal value due to instrument (hardware) effects. 3.3 STATISTICAL METHODOLOGY CONCLUSION The Westinghouse setpoint methodology results in a value with,a 95 percent l probability with a high confidence level. With the exception of Process Measurement Accuracy, Rack Drift and Sensor Drift, all uncertainties assumed are the extremes of the ranges of the various parameters, i.e., are larger than 20 values. Analog Rack Drift and Sensor Drift are assumed, based on a survey of reported plant LERs, digital Rack Drift is based on system design, and with Process Measurement Accuracy are considered as conservative values. l D0161:10 022690 36

4 WESTINGHOUSE CLASS 3 l ? TABLE 31 POWER RANGE, NEUTRON FLUX. HIGH AND LOW SETPOINTS** Parameter Allowance

• Process Measurement Accuracy

....c ...c r Primary Element Accuracy Sensor Calibration ( ).... Sensor Pressure Effects Sensor Temperature Effects [ ).... Sensor Drift g j... Environmental Allowance Rack Calibration Rack Accuracy M&TE Comparator One input Rack Temperature Effects Rack Drift l In percent span (120 percent Rated Thermal Power) l

• • Not processed by Eagle 21 racks.

ChannelStatistical Allowance = ...c a 9 9 00161:10'022690 37 i

WESTINGHOUSE CLASS 3 TABLE 3 2 POWER RANGE, NEUTRON FLUX - HIGH POSITIVE RATE AND HIGH NEGATIVE RATE" i I Parameter Allowance

• o Proce!) Measurement Accuracy

..,c l ...c Primary Element Accuracy Sensor Calibration ...c l Sensor Pressure Effects Sensor Temperature Effects ...c Sensor Drift ..c Environmental Allowance 1 Rack Calibration Rack Accuracy M&TE Comparator One input Rack Temperature Effects Rack Drift ' in percent span (120 percent Rated Thermal Power)

• • Not processed by Eagle 21 racks ChannelStatistical Allowance a

+..c 6 l 00101:1D'022690 38

WESTINGHOUSE CLASS 3 TABLE 3 3 INTERMEDIATE RANGE, NEUTRON FLUX ** Parameter Allowance i See TVA calculation SQN EEB PS Tl28-0001 Not processed by Eagle 21 racks i i L D0161:1Dt)22690 39

WESTINGHOUSE CLASS 3 -r . TABLE M ' .f SOURCE RANGE, NEUTRON FLUX ** l, Parameter Allowance i .s i See TVA calculation SQN EE8 PS Tl28 0001

/i

-i Not processed by Eagle 21 racks. j 1 1 i

I 7;

t I i .[ z! t

e

.:a i

.,t .y I i ..1 00161:10'022690 - 3 10-- .j d L. l . -. =.... -.

WESTINGHOUSE CLASS 3 i i f I TABLE 3 5 OVERTEMPERATURE AT j e Parameter Allowance

• i i

i Process Measurement Accuracy +..c + a.c i 1 l Primary Element Accuracy I i Sensor Calibration ...e Measurement & Test Equipment 'I [ ] i t Sensor Pressure Effects f i Sensor Temperature Effects I l '" Sensor Drift ..c i Environmental Allowance f Bias V,alues . a.c 1 j Rack Calibration f ..,c f ? i Measurement and Test Equipment ...e I [ 4 00161:10/022690 3-11 1 ? )

WESTIN'lHOUSE CLASS 3 TABLE 3 5 (Continued) OVERTEMPERATURE AT Parameter Allowance

• Total Rack Calibration Accuracy

. a.c i j . a.c Rack Temperature Effects _. a.c i Rack Drift AT Pressure i Al a In % span, AT. 94.5 'F, Tavo 100*F, Pressure 800 psi, Power - 150% RTP, Al t 60% al See Table 3 23 ior gain calculations Number of Hot Leg RTDs used Number of Cold Leg RTDs used ChannelStatistical Allowance = . a.c P 9 e 4 1 00161:10 022690 - 3 12

WESTINCHOUSE CLASS 3 j i t TABLE M i OVERPOWER AT Parameter Allowance

• j

+ a,C -[ Process Measurement Accuracy [ ). 4 j i Primary Element Accuracy Sensor Calibration [ [ l'" j Sensor Pressure Effects Sensor Temperature Ef fects l - t Sensor Drift l [ )... Environmental Allowance Cable IR "

• Blas Values l

s l Rack Calibration l [ )..x Measurement and Test Equipment +..t ? Total Rack Calibration Accuracy + a,C i e 1 ( ,== l-l t ^ $ I D0161:1D'022690 3-13 4 e n r-a 0

WESTINGHOUSE CLASS 3 TABLE 3 6(continued) OVERPOWER AT Parameter Allowance * + a,C Rack Temperature E ffects AT Rack Drift at Y ~ ~ in % span AT. 94.S *F, Tavg.100*F See Table 3 24 for gain calculations Per TVA Caclulation IR WCAP11239 Number of Hot Leg RTDs used i Number of Cold Leg RTDs used ChannelStatistical Allowance = + a,c l i i esua 4 O e 4 1 D0161:10t)22690 3-14

' WESTINGHOUSE CLASS 3 TABLE 3 7 PRESSURIZER PRESSURE. LOW AND HIGH, REACTOR TRIPS Parameter Allowance * . e.c Process Measurement Accuracy Primary Elemerit Accuracy Sensor Calibration M&TE Sensor Pressure Effects Sensor Temperature Ef fects I j...c Sensor Drift [ ).4 [ )...: Environmental Allowance Rack Calibration Rack Accuracy M&TE Rack Temperature Effects Rack Drift

• In percent span (800 psi)

ChannelStatistical Allowance a Pre 55urizer Pressure. Low ~ + 4.C l Pressurizer Pressure. High . a,c D0161:10 022690 3 15

WESTINGHOUSE CLASS 3 TABLE 3 8 PRESSURIZER WATER LEVEL. HIGH l Parameter Allowance

• Process Measurement Accuracy

+ a.c [ )..a Primary Element Accuracy Sensor Calibration M&TE Sensor Pressure Effects Sensor Temperature Effects Sensor Drift r Environmental Allowance Rack Calibration Rack Accuracy M&TE Rack Temperature Effects Rack Drift

• In percent span (100 percent span)

ChannelStatistical Allowance = +ex G B 4 4 D0161:10'022690 3-16

WESTINGHOUSE CLASS 3 TABLE 3 9 LOSS OF FLOW Parameter Allowance' Process Measurement Accuracy + a.c [ ).c j.u Primary Element Accuracy [ j.u Sensor Calibration g j.a Sensor Pressure Effects g j.u Sensor Temperature Ef fects [ 3.u a' Sensor Drif t ( l'" Environmental Allowance Rack Calibration Rack Accuracy [ t 0.4 percent op span)'" M&TE [ }'" Rack Temperature Effects [ l '" Rack Drift 0.3 percent op span In percent flow span (110 percent Thermal Design Flow) percent op span converted to flow span via Equation 3 26.8,with Fm., = 110% and Fu = 100% Channel Statistical Allowance = . +ac D0161:10'022690 3 17 i I

r WESTINGHOUSE CLASS 3 TABLE 310 STEAM GENERATORWATER LEVEL. LOW LOW ADVERSE AND EAM(51) (Unmodified Barton) Parameter Allowance

• l i

Process Measurement Accuracy Density variations with load due to changes q + e.c in recirculation *

• Primary Element Accuracy Sensor Calibration i

M&TE Sensor Pressure Effects Sensor Temperature Effects Sensor Drift t Environmental Allowance Transmitter. Adverse Transmitter EAM Reference Leg Heatup Adverse and EAM"* CableIR Adverse # Rack Calibration Rack Accuracy M&TE Rack Temperature Effects Rack Drift In percent span (100 percent span)

• • See Table 3 25 for explanation PerTVAcalculation 1 LT 3 38 Per TVA calculation IR WCAP 11239 Channel Statistical Allowance =

Steam Generator Level-low low (EAM) +a.c Steam Generator Level low low (Adverse) ~ + 8.t D0161:10022690 3 18

WESTINGHOUSE CLASS 3 i TABLE 311 STEAM GENERATOR WATER LEVEL. LOW LOW ADVERSE AND EAM (51) (Modified Barton) r Parameter Allowance

• Process Measurement Accuracy d

Density variations with load due to changes +a4 in recirculation" Primary Element Accuracy Sensor Calibration M&TE Sensor Pressure Effects Sensor Temperature Effects Sensor Drift Environmental Allowance Transmitter. Adverse Transmitter EAM Reference Leg Heatup Adverse and EAM"* Cable IR-Adverse # Rack Calibration Rack Accuracy M&TE Rack Temperature Effects Rack Drift In percent span (100 percent span)

• • See Table 3 25 for explanation Per TVA calculation 1 LT 3 38 Per TVA calculation IR WCAP 11239 Cheve! Statistical Allowance =

Steam Generator Level low low (EAM) .+ac Steam Generator Level low low (Adverse) ~ +ax = l l D0161:1D.022690 3-19 )

WESTINGHOUSE CLASS 3 TABLE 312 CONTAINMENT PRESSURE. HIGH, EAM AND HIGH.HIGH (FO) SORO) Parameter Allowance * +a.c Process Measurement Accuracy Primary Element Accuracy Sensor Calibration M&TE Sensor Pressure Effects Sensor Temperature Effects Sensor Drift Environmental Allowance EAM High and High High Rack Calibration Rack Accuracy M&TE Rack Temperature Effects Rack Drift

• In percent span (16 psig)

ChannelStatistical Allowance a L High and High High . + a.c EAM +a.c m W 4 ( D0161:1D'022690 3 20 l l

WESTINGHOUSE CLASS 3 TABLE 313 CONTAINMENTPRES5URE HIGH,EAM AND HIGH HIGH(BARTON) Parameter Allowance * . a.c i Process Measurement Accuracy Primary Element Accuracy Sensor Calibration i M&TE t Sensor Pressure Effects Sensor Temperature Effects High and High High EAM 5ensor Drift Environmental Allowance (High and High High only) Rack Calibration Rack Accuracy M&TE Rack Temperature Ef fects Rock Drift

• In percent span (18 psig)

Channel $tatistical Allowance a High and High-High + a.c EAM 9 ae$ l e a 0 00161:10 022690 3 21

WESTINGHOUSE CLASS 3 t TABLE 314 PRES $URIZER PRE $$URE. LOW, SAFETY INJECTION Parameter Allowance * . a.c Process Measurement Accuracy Primary Element Accuracy $ensor Calibration M&TE $ensor Pressure Effects Sensor Temperature Effects $ensor Drift Environmental Allowance Rock Calibration Rack Accuracy M&TE Rack Temperature Effects Rack Drift

• In percent span (800 psi)

ChannelStatistical Allowance a +a.c I m 4 5 I l 00161:10t)22690 3 22

WESTINGHOUSE CLASS 3 TABLE 315 STEAMLINEPRES$URE LOW 4 Parameter Allowance * + a.c Process Me45Urement Accuracy Primary Element Accuracy Sensor Calibration M4TE Sensor Pressure Effects $ensor Temperature Effects Sensor Drift Environmental Allowance Rack Calibration Rock Accuracy M&TE Rack Temperature Effects Rack Drift

• In percent Span (1200 plig)

Channel $tatistical Allowance s . +at O e 4 5 00161:10/022690 3 23

WESTINZHOUSE CLASS 3 TABLE 316 NEGATIVE $TEAMLINE PRESSURE RATE. HIGH i Parameter Allowance * ~ ~ Process Measurement Accuracy Primary Element Accuracy Seneor Calibration + a,c Sensor Pressure Effects Sensqr Temperature Effects + a,c Sensor Drift + a,c Environmental Allowance Rack Calibration Rack Accuracy Measurement & Test Equipment Accuracy Rack Temperature Effects Rack Drift

• In percent span (1200 psig)

Channel 5tatistical Allowance . + e.C 9 I e G 4 D0161:1D'022090 3 24

WESTINGHOUSE CLASS 3 TABLE 317 STEAM GENERATOR WATER LEVEL.HIGH HIGH (51) Parameter Allowance

• Process Measurement Accuracy

...c density variations with load" Primary Element Accuracy Sensor Calibration M&TE 5ensor Pressure Effects Sensor Temperature Effects Sensor Drift Environmental A'towance Rack Calibration Rack Accuracy M&TE Rack Temperature Ef fects Rack Drift

• In percent span (100 percent span)

" See TVA calculation SQN C55 005 ChannelStatistical Allowance = a.c 6 a D 6 00161:10'022690 3 25

WESTINGHOUSE CLASS 3-i TABLE 318 RWST LEVEL LOW AND HIGH Parameter Allowance See TVA Calculation SQN.EEB MS T128-0015 for RWST Level and TVA calculation SQN EEB MS-Tl28 0013 for Reactor Building Sump Level. l l .M 00101:10'022690 3 26

l WESTINGHOUSE CLASS 3 TABLE 319 i RCP UNDERFREQUENCY (W SDF 2)** i Parameter Allowance

• I a

. + a.c Process Measurement Accuracy I Primary Element Accuracy Sensor Calibration M&TE Sensor Pressure Effects Sensor Temperature Effects t Sensor Drift Environmental Allowance I Rack Calibration Rack Accuracy M&TE Comparator One input Rack Temperature Effects Rack Drift

• In percent span (6 Hz)
  • Not processed by Eagle 21 racks Channel Statistical Allowance =

+ a.c l =. i 00161:10'022690 3 27

WESTINGHOUSE CLASS 3 1 i TABLE 3 20 l RCP UNDERVOLTAGE (GE NGV 13)* Parameter Allowance { T l TVA OE calculation No. RCP UV. Device 27 System 202 RIMS accession # B43 '860221902 Not processed by Eagle-21 racks D P 4 e 9 D0161:10/022690 3 28

WESTINGHOUSE CLASS 3 TABLE 3 21 VESSEL.iT EQUIVALENT TO POWER Parameter Allowance

• Process Measurement Accuracy

[ j.. _.4 Primary Element Accuracy Sensor Calibration g 3.u Sensor Pressure Effects Sensor Temperature Effects Sensor Drift [ ).u Environmental Allowance Cable IR*" Bias Values Rack Calibration [ ).u Measurement and Test Equipment [ j.u Total Rack Calibration Accuracy +a4 = e e I i D0161:10 022690 3 29 a

WESTINGHOUSE CLASS 3 i 4 TABLE 3 21(Continued) VESSEL AT EQUlVALENT TO POWER l Parameter Allowance * + a,c ~ ~ Rack Temperature Effects AT Rack Drift AT in % span AT = 94.5'F, T vg 100*F See Table 3 21 for gain calculations Per TVA calculation IR WCAP 11239 Number of Hot Leg RTDs used Number of Cold Leg RTDs used ChannelStatistical Allowance s + a,c i i t i i l D0101:10'022690 3 30-

l aw w wr$ttwCHOUSE CLA$$ 3 notes FOR I. ALL VALUES IN PERCENI $PAh.

10. $UPERSEDE$ INFORMA110N IN F$AR TADLE 16.1 3-l

2. A$ N0f E0 IN T ABLE l$.I.3+1 0F FS AR l l.t 3*

3. AS CALCUL ATED VSING fME APPROVED METHODOLOCT 824

)**** AND NOTED ON TADLE 4 3 0F THl$ REPORI. ( ) 4,, 3 93, 3... e.e [ j ,q )... $. NOT U$ED IN $AFEf f AN AL T$l$ ( ) $. At N0l[0 IN FICURE 15 4.3 1 0F F$ AR 1$. NOT IN WE$f1NGHOU$[ $CDPE * $EE f v A CALCUL Af!ON F. A$ NOTED IN TABLE 2 2*l N0fE I $0N*[EB P$all29-0001. OF PL ANT TECHNICAL $PECIFICATIONS

16. INCORE/EXCORE f tell COMPARISON A$ N0fE0 IN

8. A$ NOTED IN TABLE 2 2*l N0ft 3 I ABLI. 4 3*l DF PL ANT IECHNICAL $PECIFIC ATION$

OF PL ANT TECHNIC AL $PECIFIC AflDNS 11.t 3*

9. NOT NOTED IN TABLE 15.1.3 1 0F FSAR But

10. $AFE f f Ah Alf$ls LIMll [NSURE$ THl$ RWSI $VlfCHOVER TO USED IN $AFEf f ANALT$l$

CONIAINMENT LUMP l$ COMPLETED BEFORE YORTEXING OCCUR $ IN THE I 1ABLE RF AC104 PR0f EC f l0N $'$f EM/ AC TU A'104 $t $f EM CH Ai $E000*A*t UN11% i At Stat 0R 1 e 1 a P 8 , RCittfl04 CMakWEL g{g gMy Call 8jA gg RR,t,t tu,RE t' 10h gRt OR 1 th Rg ACCURAC1 ACC Att (H til til Ett II) t ._P0wtp R AhCt htUf RON PLUW

• Nt GM titR0t hf t

POWER R ANCE. htutRON FLUW

• LOW ttf ?0th?

3 Pytp Rahtt. pgeon FLOW + Nttu Politivt Raf t 4 POWtR Raket. AtUtPON FLOW NICH htcattyt Ratt I thf t#Mt01stt R&hCt. ktUtRDh f tUr 6 SOUpft RaN %. 3 D inow FLUt F. Ovtpft etRAtutt of a 1 tHamwit 8 tav0 thak4tt I 10 PRittualitR PRtstvRt CHA44tl l 11 F ie l) tHamatt I lt evt#*0WER t a t cua==tt I 13 l 14 tave C*Akutt 15 PatttVRiftR PRtitVRt

• LOh. Riat?0R falP (BART0Ni 16 PRtttuttrtR FREttuRE - ricM (9 4R T oni l

17 PRttsuRittp WattR tivtl

• M16M te aR T ON S le tott OF FLOW l

19 tif AM $tNF#af 0R WattR trygt

• tov t0w A0ytRtt nyo0 trit 0 gapt0m, to tit AM ctattaf 0R baf te Ltett
• LOW *l0W ( AM (L*M001Flt0 9 arf 0k1 l

St $ttAM CINER ATOR WAf tR Littl = LOV LOW A0vtttt (M001Ftt0 94Rfou) I tt $f t AM CEN(R&f 0R Waf tR LEV [L

• t0W LOW ( AM IM00tFit0 S'o tDN) 33 UNotRv0Linct - #cp to tectRFRt0VtNCT * #CP I

28 CONTAtwMtut PRtttutt - EAM (F 0190R01 26 C0#1AthMtat PatttuRE

• M10H (F 0 V R OR O'e RF CONTA1k T hi PRittVRC - MitH-MICH (F0v80R01 30 CentAthM ut PRtttVRt (AM (g ARien t I

19 M AtWMitt PRtttVRt - Hj$H tBA#f0NI 3C CONT AjWTEt PRittVRt

• MlCM M19H (pa#f0ml 31 PRttsuRt!!# PetttVRE
• LDw, si t94Rion) 33 titam lat PRtstopt = LOW (F0190#01

,33 tit AM crutR ATOR W4f te Ltytt. nicM-uicH teAnf0mi 34 RWttLtvit -LOW (9 Ant 0Nt 33 Rvst (tytt

• N10H (S ARIONI 34 NEGAf tVE STt A%)NE PRittVRt Rif t
• M10M 3F _vitstL et (Ovivattet 10 P0vtp me w

-.,7 - 10:03e 45 02*flAR*90 FABLE 3 32 PACE 3 3l 19

20. NOT IN WESilNCHOUSE SCOPE - SEE TVA CALCUL ATION RCP-UV-DEVICE 27-SYSTEM 202 21 4 J ** "

224 3'"'

23

24. NOT IN WESilNCHOUSE SCOPE - SEE TV A CALCUL ATION $0N.EEB-MSall28 00lS 25.

. 26. SAFETY AN ALYSIS LIMll. ENSURES THAT AT RWST SWITCH 0 VERE THE CONT AINMENT SUMP LEVEL SAFEf f LIMil IS NOT V10L ATE 0e b1-

27. CABLE'!Re AS PROVIDED BY TVA. TREATED AS A BIAS.

IWSI

28. NOTE 5 0F 1ABLE 2 2 1 0F PLAki TECHNICAL SPECIFICAfl0NS.

APERTURE

29. PER TV A CALCUL Ai!DN SON. CSS 005.

{g@ = 3 23 1 TNCINEERfD SAFf ty rE AtgqEs ISO Available On NFL IQQOst QLLOWANCt M Aperture L,ard oa efVisiON s IN$1 RUM (NT RACK t to 11-12 13 14 15 16' tF la ~ 19 CTCL C AL19R Af l0N M&lt COMPARATOR (EMPfRATURE ORIFf S AF(IT STB Sf3 TOTAL CHANNEL MARolN NCE ACCUR ACT ACCURACT $(filNG EFFECt$ (t) AN AL T $l$ ALLOWABLE IRIP ALL0vANCE $f A!!$f1C AL (t) (1) (1) ACCURACT (in .LIMlf V AL UE $(TPOINI (1) ALL0wANCE o (1) (2) (3). (3). (Il

I

.e.e - l 1 ee.e 10 ftSt RTP 111.4% RTP 1994 RfP P.S 1.0 35% RTP 27.41 RTP 251 RTP 83 2 V 0.S (5) 6.3% RTP 5 01 PTP 3 i 0.6 6.92 RTP (9) 6.3% RTP 6.01 RTP 16 4 (161 (1) (13) 2$1 RTP l (1 51 (5) (15) 1.06 05 CPS 6 04 7 0 (6) (7)

• t.9% et see.

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4. 4 '

25 l 0.3 2 42 esie(9) 1.6 esos 1.54 esta 5.5 26 03 3.69 este (91 2 9 sets 2 8) esta 5.5 27 l 0.3 1.2 pese (9) 0.6 seen 0.5 esta 3.9 28 f I 0.3 2.42 se.e (9) ..r e... f.54 es.. 49 29 i 0.3 3.69 esta (9) 2.9 esse 2 01 este 4.9 30 - 4 0.3 1730 sets (101 1864.4 es t e 1870 esse 17.5 31 _1 03 433 estetti $92 2 seie 600 este 13.9 32 j 0.3 93.22 ene. (101 81.7 2 eses el 01 eee. 12.2 33 (24) (10) (241 (24) 27.41.... (24) 34 (24) (24) (26) (24) 27 42 eso. (24 ) 3$ 0.3 (51 107.8 eeea 100.0 eete 36 1.2 6.02 et e,e. (9) (26s (20) e 1.71 af esoe (281 6.0 37 [ 9b05 b (DDb7 -o \\ l

WESTINGHOUSE CLASS 3 TABLE 3 23 . OVERTEMPERATURE AT GAIN CALCULATIONS The equation for Overtemperature ATis: 1+t5 4 Overtemperature AT ( 1 + t 8) s s 1+sS g AT, {K - K ( t g ) {T - T'} + K (P-P') - f (AI)} g 2 3 g Ki (max) (1.2357 (analysis value)]'" = K (nominal) 1.15 (Technical Specification Trip Setpoint) - i = K2 = 0.011 K3 = 0.00055 Vessel Ts = 609.7'F Vessel Tc = 546.7'F Positive al gain 0.86% FP Al/% Al = AT span (609.7 546.7)(150)/(100) = = 94.5'F Process Measurement Accuracy i i AT +a.c PMA = = = Al PMA1 = i a l { = .i PMA2 = = = M G e .4 9 k 00161:10,022690 3-32

s WESTINGHOUSE CLASS 3 . TABLE 3 23(Continued) OVERTEMPERATURE AT GAIN CALCULATIONS Pressure Gain

• +aC Gain a

= Pressure Channel Uncertainties + a.c SCA = = 3 M&TE = = - f = STE = = = SD = = = Bias = = = Total Allowance + a.c l = l = l 1 I 4 4 00161:10/022690 3-33

WESTINGHOUSE CLASS 3 TABLE 3 24 - OVERPOWER AT GAIN CALCULATIONS The equation for Overpower AT is: l 1 +t S 4 Overpower 6T (1 +t S) s l_ 3 58 3 AT, {K - K ( l + t g W-K @ - W ION 4 3 g 2 9 (1.1590 (analysis value)]'" K (max) 4 = 1.087 (Technical Specification Trip Setpoint) K (nominal) 4 = K5 = 0.02 K6 = 0.0011 Vessel Ts 609.7'F = Vessel Tc = 546 7'F (609.7 546.7)(150)/(100) AT span =- 94.5'F = Process Measurement Accuracy l AT + a,c PMA = = = Total Allowance 1 + a,c TA = = = ~ e e I: 00161:1D 022690 3-34

WESTINGHOUSE CLASS 3 TABLE 3 25 STEAM GENERATOR LEVEL DENSITY VARIATIONS Because of density variations with load due to changes in recirculation,it is impossible without some form of compensation to have the same accuracy under all load conditions. In the past the 1 recommended calibration point has been at 50 percent power conditions. Approximate errors at 0 percent and 100 percent water level readings and also for nominal trip points of 10 percent and 70 percent level are listed below for a typical 50 percent power condition calibration. This is a general case and will change somewhat from plant to plant. These errors are only from density changes and do not reflect channel accuracies, trip accuracies or indicated accuracies which have been defined as - AP measurements only,W - Analysis specific for Sequoyah Units 1 and 2 indicates that the level density error is less than 11.0% of span. This is based on the calibration procedure used at Sequoyah which is different than the recommended calibration at 50% power,50% level conditions. ~This error only affects the high level trip function, INDICATED LEVEL (50% Power Calibration) 0% 10 % 70 % 100 % + 4.C Actual Level, 0% Power Actual Level 100% Power i 1 l 1 (1) Miller, R. B., " Accuracy Analysis for Protection / Safeguards and Selected Control Channels", WCAP-8108 (Proprietary), March 1973. D0161:1D/022690 3-35

WESTINGHOUSE CLASS 3-l TABLE 3 26 AP MEASUREMENTS EXPRESSED IN FLOW UNITS The AP accuracy expressed as percent of span of the transmitter applies throughout the measured span,i.ei, + 1.5 percent of 100 inches AP = + 1.5 inches anywherein the span. Because F3 = f(AP)- l' the same car:not be said for flow accuracies. When it is more convenient to express the accuracy of a l-transmitter in flow terms, the following method is used: 1 1 F2 ; 3pN* 2F aF3 = BAP3 g aAPN Eq. 3 26.1-thus aFN = 2F g Error at a point (not in percent)is: aF aAP dAP N N N Eq. 3 26.2. ( - - - = = ( F 2-2AP N 2F 3 and l l 2 AP" F" where max = maximum flow Eq. 3 26.3 = p ma max and the transmitter AP error is: 8Py x 100 = perrent error (full scale AP) Eq. 3-26.4 p max ( percent error (FS AP)) aF AP 2 P percent error (FS AP) [ F m82 N 100 3 2 2 x 100 \\ F,,, g [p \\ 2APmax \\ p / max Eq. 3-26.5 l. l 1 00101:1D<022690 3-36

WESTINGHOUSE CLASS 3 TABLE 3 26(Continued) AP MEASUREMENTS EXPRESSED IN FLOW UNITS J [ Error in flow units is: ? p reent error (FS AP) F, Eq. 3 26.6 aFN=FN 2 x 100 - F - l g. Errorin percent nominal flow is: P* N = Eq. 3-26.7 x 100 = P 2 'P g g Errorin percent full span is: aF Fg (pemnt earWM F,,, [ g F, x 100 = F, x 2 x 100 F x 100 3 percent error (FS AP) F max Eq. 3 26.8 - 2 ..P g Equation 3 26.8 is used to express errors in percent full span in this document. L d ii 1 D0161:10 022690 3-37 l l

WESTINGHOUSE CLASS 3 I i 4.0 TECHNICAL SPECIFICATION USAGE 4.1 CURRENT USE The Standardized Technical Specifications (STS) as used for Westinghouse type plant designs (see NUREG-0452, Revision 4) utilizes a two column format for the RPS and ESF system. This format recognizes that the setpoint channel breakdown, as presented in Figure 4-1, allows for a certain amount of rack drift. The intent of this format is to reduce the number of Licensee Event Reports'(LERs) in the area of. instrumentation setpoint drift. It appears that this approach has been successful in achieving its goal. However, the approach utilized does not recognize how setpoint; calibrations and verifications are performed in the plant, in fact, this two column. approach forces the plant to take a double penalty in the area of calibration error. As noted in Figure 4-1, the plant must allow for calibration error below the STS Trip Setpoint, in addition to the allowance assumed in the various accident analyses, if full utilization of the rack drift is wanted. This is due, as noted in 2.2, to the fact that calibration error may not be distinguished from rack drift after an initial calibration. Thus, the plant is left with two choices; 1) to assume a rack drift value less than that allowed for in the analyses (actual RD = assumed RD RCA) or,2) penalize the operation of the plant (and increasing the possibility of a spurious' trip) by lowering the nominal trip setpoint into the operating margin. The use of the summation technique described in Section 2 of this report allows for - a natural extension of the two column approach. This extension recognizes the calibration / verification techniques used in the plants and allows for a.more flexible i approach in reporting LERs. Also of significant benefit to the plant is the incorpor-ation of sensor drift parameters on an 18 month basis (or more often if necessary). 4.2 WESTINGHOUSE SETPOINT METHODOLOGY FOR STS SETPOINTS Recognizing that besides rack drift the plant also experiences sensor drift, a different approach to technical specification setpoints may be used. This revised methodology accounts for two additional factors seen in the plant during periodic surveillance,1) interactive effects for both sensors and rack and,2) sensor drift - effects. D0161:10.022690 4

• WESTINGHOUSE CLASS 3 4.2.1 RACK ALLOWANCE The first item that will be covered is the interact!ve effects. When an instrument technician looks for rack drift he is seeing more than that, if "as left as found" data is not used. This interaction has been noted several times and is treated in Equations 2.1 and 3.1 by the arithmetic summation of rack drift, rack measurement-and test equipment accuracy, rack comparator setting accuracy, and rack calibration accuracy (for analog rack effects); rack drift, rack measurement and test equipment accuracy and rack calibration accuracy (for digital rack effects); and sensor drift, sensor measurement and test equipment accuracy and sensor calibration accuracy (for sensor effects). To provide a conservative " trigger value", the difference between the STS trip setpoint and the STS allowable value is determined by two methods. The first is simply the values used in the CSA calculation, T1 = (RD +

RCA + RMTE + RCSA) for analog racks; T3 =(RD.+ RCA + RMTE) for digital racks. The second extracts these values from the calculation and compares the remaining values against the total allowance as follows: T2 = TA -({A + (S)2)u2 + EA) (Eq. 4.1) where: T Rack trigger value = (PMA)2 + (PEA)2 + (SPE)2 + (STE)2 + (RTE)2 A = S (SCA + SMTE + SD) = EA, TA and all other parameters are as defined for Equations 2.1 and 3.1. The smaller of the trigger values should be used for comparison with the "as measured" value (RD + RCA + RMTE + RCSA for analog racks, RD + RCA + RMTE for digital racks). As long as the "as measured" value is smaller, the channel is well within the accuracy allowance. If the "as measured" value exceeds the " trigger value", the measured values should be used in the calculation described in Section 4.2.3. This means that all the instrument technician has to do during the periodic surveil-lance is determine the value of the trip setpoint (bistable trip setpoint - analog racks, D0161 10:022690 4-2

. WESTINGHOUSE CLASS 3 l 1 l trip setpoint as indicated by the MMI - digital racks), verify that it is less than the j STS Allowable Value, and does not have to account for any additional effects. The [ same approach is used for the sensor, i.e., the "as measured" value is used when required. Tables 41 and 4-2 show the current STS setpoint philosophy (NUREG. 0452, Revision 4) and the Westinghouse rack allowance (one analog, one digital). A comparison of the two different Allowable Values will show the net gain of the j Westinghouse versions. Note that the digital channel error magnitude difference is. due primarily to the reduced RCA and RD values when compared to the analog channel errors. 4.2.2 INCLUSION OF "AS MEASURED" SENSOR ALLOWANCE - If the approach used was a straight arithmetic sum, sensor allowances for drift would also be straight forward, i.e., a three column setpoint methodology. However, the use of the Westinghouse methodology requires a somewhat more complicated approach. This methodology is based on the use of equation 4.2, and demonstrated in Section 4.2.3, implementation. {A}u2 + R + S + EA s TA (Eq. 4.2) where: i l R the "as measured rack value" (RD + RCA + RMTE + RCSA for = analog racks, RD + RCA '+ RMTE for Digital Racks) l S the "as measured sensor value" (SD + SCA + SMTE) = and all other parameters are as defined in Equation 4.1. Equation 4.2 can be reduced further, for use in the STS to: Z + R + S s TA (Eq. _4.3) where: Z = {A}v2 + EA 00161:10,022690 43 l

WESTINGHOUSE CLASS 3 i 4 Equation 4.3 would be used in two instances,1) when the _"as measured" rack j setpoint value exceeds the rack " trigger value" as defined by the STS' Allowable Value, and,2) when determining that the "as measured" sensor value is within-acceptable values as utilized in the various Safety Analyses and verified every 18'- months. 4.2.3 IMPLEMENTATION OF THE WESTINGHOUSE SETPOINT METHODOLOGY Implementation of this methodology is reasonably straight forward, Appendix _ A l provides a text and tables for use at Sequoyah. An example of how the specifica-tion would be used for the Pressurizer Water Level-High reactor trip is as follows.- For the periodic surveillance, as required by Table 4.3-1 of NUREG-0452, Revision 4, a functional test would be' performed on th'e channels of this trip function. During this test the bistable trip setpoint would be determined for each channel, if the "as measured" bistable trip setpoint error was found to be less than or equal to that required by the Allowable Value, no action would be necessary by the plant sfaff. The Allowable Value is determined by Equation 4.1 as follows: T2 = TA - ({A + (S)2)u2 + EA) where: TA = 6 percent (an assumed value for this example) + a,C A = (5)2 = EA = T2 = = = = = i l l 00161:1 D'022690 4-4 L

a WESTINGHOUSE CLASS 3 However. since only (0.65 percent]'" is assumed for T in the various analyses (RCA + RMTE + RD), that value will be used as the " trigger value". The lowest of two' -] values is used for the "tngger value"; either the value for T ' assumed in the analyses or the value calculated by Equation 4.1. Now assume that one channel's signal conditioning card has " drifted" more than that allowed by the STS for periodic surveillance. According to ACTION statement b.1, the plant staff must verify that Equation 2.2-1 is met. Going to Table 2.21,.the following values are noted:- Z = 2.14 and the assumed Total. Allowance is (TA) = l 8.0. Assume that the."as measured" rack setpoint value as determined with the - MMI is 4.25 percent low and the "as measured" sensor value ~is 2.5 percent. Equation 2.2-1 looks like: Z + R + S s TA 2.14 + 4.25 + 2.5 s 8.0 8.9 > 8.0 As can be seen,8.9 percent is not less than 8.0 percent thus, the plant staff must follow ACTION statement b.2 (declare channel inoperable and place in the " tripped" condition). It should be noted that if the plant staff had not measured the sensor i drift, but instead.used the value of S in Table 2.2-1 then the sum of Z + R + S I would also be greater than 8.0 percent.. In fact, for analog process rack channels, \\ almost anytime the "as measured" value for rack drift is greater than T (the " trigger value"), use of S in Table 2.2-1 will result in the sum of Z + R + S being greater than TA and requiring the reporting of the case to the NRC. For digital process rack channels this will occur less often due to the increased margin available. Reduction of process rack errors without setpoint adjustment created this additional margin. If the sum of R- + S was about one percent less, e.g., R = 3.5 percent, S = 2.0 percent thus, R + S = 5.5 percent, then the sum of Z '+ R + S would be less than 8 percent. Under this condition, the plant staff would recalibrate the instrumentation, as good engineering practice suggests, but the incident is not reportable, even ' l-though the " trigger value" is exceeded, because Equation 2.2-1 was satisfied. However, for a digital process rack channel, the amount of drift used in the example is more indicative of possible failure rather than an acceptable level of drift. Rack 1 00161:1D 022690 45 o

aa WESTINGHOUSE CLASS 3 drift in excess of (~ 0,5% span)+a.c is considered abnormal and should be thoroughly investigated. In the determination of T for a function with multiple channelinputs there is a slight l disagreement between Westinghouse proposed methodology and NRC approved methodology. Westinghouse believes that T should be either: (RCA1 + RMTE1 + RCSA1 + RD1) + (Eq. 4.4) T12 = (RCA2 + RMTE2 + RCSA2 + RD2) or T22 TA - {A + (S1)2 + (S2)2)u2 - EA (Eq. 4.5). = where the subscripts 1 and 2 denote channels 1 and 2, and the value of T used is whichever is smaller. The NRC in turn has approved a method of determining T_ for a multiple channel input function as follows, either: i Ta {(RCA1 + RMTEi + RCSA1 + RD )2 + = 1 + (RCA2 + RMTE + RCSA2 + RD )2}1/2 (Eq. 4.6) 2 2 or Equation 4.5 as described above. l l Again the value of T used is whichever is smaller. This method is described in NUREG-0717 Supplement 4,- dated August 1982. An example demonstrating all of the above noted equations for Overtemperature AT is provided below: - + a,C l TA = l A = (51)2 (52)2 = + a,c RCA + RMTE + RD g g t l l D0161:1D/022690 4-6

WESTINGHOUSE CLASS 3 . +..c RCA + RMTE + RD2 = 2 2 RCA + RMTE3 + RD3 = 3 EA = Using Equation 4.4; ...c T12 = = Using Equation 4.5; + a.C T22 = = '{ Using Equation 4.6; + e.c T3 = = i The value of T used is from Equation 4.6. In this document Equations 4.5 and 4.6, whichever results in the smaller value, are used for multiple channel input functions j to remain consistent with current NRC approved methodologies. Table 4 3 notes the values of TA, A, S, T, and Z for all protection functions and is utilized in the determination of the Allowable Values noted in Appendix A. 1 Table 4.3-1 also requires that a calibration be performed every refueling (approximately 18 months). To satisfy this requirement, the plant staff would determine the process rack only, trip setpoint (thus, determining the "as measured" rack value at that time) and the sensor "as measured" value. Taking these two "as measured" values and using Equation 2.2-1 again the plant staff can _ determine that l the tested channel is in fact within the Safety Analysis allowance. l

4.3 CONCLUSION

I 4 4 Using the above methodology, the plant gains added operational flexibility and yet remains within the allowances accounted for in the various accident analyses. In addition, the methodology allows for a sensor drift factor and an increased rack drift i 00161:1D/022690 4-7

WESTINGHOUSE CLASS 3 ' I - i factor. These two gains should significantly reduce the problems' associated with' channel drift and thus, decrease the' number of LERs while allowing plant operation in a safe manner. e I h - \\ s E ' f k .i .e b e l D0161:10:022690 4-8 l l

b ' WESTING' HOUSE CLASS 3 TABLE 4-1. EXAMPLES OF CURRENT STS SETPOINT PHILOSOPHY (Analog) (Analog)

Power Range '

Pressurizer-Neutron Flux - Hiah. Pressure - Hiah Safety Analysis Limit 118 percent - 2445 psig. t STS Allowable Value 110 percent 2395 psig-- STS Trip Setpoint 109 percent. '2385 psig TABLE 4 2 EXAMPLES OF WESTINGHOUSE STS RACK ALLOWANCE l (Analog) ~ (Digital). Power Range . Pressure - Hiah-Pressurizer Neutron Flux - Hiah Safety Analysis Limit 118 percent . 2445 psig. I STS Allowable Value 111.4 percent : 2390.2 psig (Trigger Value) STS Trip Setpoint 109 percent 2385 psig l-D0161:10/022690 4-9 l

g WESTINGHOUSE CLASS 3 i 4Y Safety Analysis' Limit i............. { Process Measurement Accuracy. l............. { Primary Element Accuracy j l............. { Sensor Calibration Accuracy-r I............. .{ Sensor Measurement & Test Equipment: I.............. { Sensor Pressure Effects .(............. { Sensor Temperature Effects i............. { Sensor Drift l 1............. { -- Environmental Allowance i I............. { Rack Temperature Effects i.......... .{ Rack Comparator Setting Accuracy - I...........- {: Rack Calibration Accuracy. l.............- { Rack Measurement & Test Equipment STS Allowable Value I..........-. { . Rack Drift l: STS Trip Setpoint Actual Calibration Setpoint I' 1 Figure 41 NUREG 0452 Rev.4 Setpoint Error Breakclown 1 00161:10/022690 4 10

WESTINGHOUSE CLASS 3 -- 1 I Safety Analysis limit 4 l............. { Process Measurement Accuracy j l............. i { Primary Element Accuracy I............. {- SensorCalibration Accuracy 1...........- -l { Sensor Measurement & Test Equipment-i............. {. - Sensor Pressure Effects-I..-.......... -{ SensorTemperature Effects I... { Sensor Drift i............. { Environmental Allowance i............. { . Rack Temperature Effects - STS Allowable Value I............. { Rack Comparator Setting Accuracy. l............. { Rack Calibration Accuracy I......... - -{ Rack Measurement & Test Equipment [............. I {' Rack Drift STS Trip Setpoint l t '1 e Figure 4 2 Westinghouse STS Setpoint Error Breakdown. Analog Process Racks i J 0010 t::0:022690 4 11 ~l 4 ~

WESTINGHOUSE CLASS 3 j 1 Safety. Analysis Limit ] i 1 1.............. { Process Measurement Accuracy-l.............

• ' j

{ Primary Element Accuracy - l............. { SensorCalibration Accuracy l............. { Sensor Measurement & Test Equipment j l............. { Sensor Pressure Effects I............. { Sensor Temperature Effects I............. 7 { Sensor Drift i I............. { Environmental Allowance I........... { RackTemperature Effects i............. STS Allowable Value { Rack Calibration Accuracy l............. { Rack Measuremen_t & Test Equip _ ment I............. { Rack Drift STS Trip Setpoint f Figure 4 3 Westinghouse STS Setpoint Error Breakdown. Digital Process Racks c [. D0161:10'022690 4-12 i l. [

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a0iOJi31 02*MAA to STEM STS SETPOINT-INPUTS TS 1 AND 2 INSTRUMENT STS-TRIP STS ALLOWABLE MAXlMUM (9) (9) SPAN SETPOINT VALUE VALUE (3) (Z) (4)- (7) 20 4.%6 120Y RTP 1091 R'P 111.41 9fP I 2.D 4.96 1201 mfd 23I #fP 27.8T R'P I' t.1 0.13 1201 GTP 3.Dt RTP t.3I RTP 3-I.t D.50 1201 4TP' S,01 # f P E.31 R'P 4 flei flei t l 4) 251 RTP f 14 ? I fl e) (t el f 141 1.Df*01 FPS fiel 9 2.93 fit tRI f91st,91 o' SPAN F t.' 2.39 f6) fill f i ll

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WESTINGHOUSE CLASS 3 'i APPENDIX A SAMPLE SEQUOYAH i SETPOINT TECHNICAL SPECIFICATIONS 1 1 i D0161:1D 022690 A-1 S

WESTINGHOUSE CLASS 3 ~ ( SAFETY LIMITS AND LIMITING SAFETY SYSTEM SETTINGS 2.2 LIMITING SAFETY 3YSTEM SETTINGS o l REACTOR TRIP SYSTEM INSTRUMENTATION SETPOINTS 2.2.1 The Reactor Trip System Instrumentation and Interlock Setpoints shall be set consistent with the Trip Setpoint values shown in Table 2.21. APPLICABILITY: As shown for each channel in Table 3.31. 1 1 ACTION: a. With a Reactor Trip System Instrumentation or interlock Setpoint less conservative than the value shown in the Trip Setpoint column but more conservative than the value shown in the Allowable Value Column of Table I 2.21, adjust the Setpoint consistent with the Trip Setpoint value.- ~ b. With the Reactor Trip System Instrumentation or lnterlock Setpoint less conservative than the value shown in the Allowable Values column of. Table L 2.21, either: 1. Adjust the Setpoint consistent with the Trip Setpoint value of Table 2.2-1 and determine within 12 hours that Equation 2.2-1 was satisfied for the affected channel or l 2. Declare the channelinoperable and apply the applicable ACTION statement requirement of Specification 3.3.1 until the channel is restored to OPERABLE status with its setpoint adjusted consistent with the Trip L Setpoint value. l* EQUATION 2.21 Z + ' R + S s TA where: Z The value from Column Z of Table 2.2-1 for the affected channel, = D0161:lO-022e90 A-2 / w

WESTINGHOUSE CLASS 3, R The "as measured" value (in percent span) of rack error for the affected =

channel, S

. Either the "as measured" value (in percent span) of the sensor error, or = the value from Column S (Sensor Drift)'of Table 2:2-1 for the affected channel, and TA. The value from Column TA (Total Allowance) of Table 2.2-1 for the. = affected channel. n ~ 1 l W .f I l q i 9 i 00101:1 D'022690 A-3

WESTINGHOUSE CLASS 3 TABLE 2.2-1 REACTOR TRIP SYSTEM INSTRUMENTATION TRIP SETPOINTS Total sensor Functional Unit Allowance (TA) Z, Drift (5) Trip setpoint Allowable Value 1. Afsanual Reactor Trip NA NA 'NA NA NA 2. Power Range, Neutron Flux, 7.5 4.56 0 s 109% of RTP s 111.4% of RTP High 5etpoint Low Setpoint 8.3 4.56 0 s 25% of RTP s 27.4% of RTP 3. Power Range, Neutron Flux, 1.6 0.50 0 s 5% of RTP with a time s 6.3% of RTPwith a time High Positive Rate constant 2 2 seconds constant 2 2 seconds 4. Power Range, Neutron Flux, 1.6 0.50 0 s 5% of RTPwith a time s 6.3% of RTP with a time. High Negative Rate constant 2 2 seconds constant 2 2 seconds 5. Intermediate Range, NWS NWS NWS $ 25% of RTP . s NWS Neutron Flux 6. Source Range, Neutron Flux NWS NWS NWS. s 105(ps s NWS 7. Overtemperature AT 5.7 2.93 1.6 + 0.6** See note 1 See note 2. 8. Overpower AT 4.8 ' 2.39 1.6 See note 3 See note 4 9. Pressurizer Pressure - Low - 15.6 2.06 2.0 21970 psig. 21964.8 psig 10. Pressurizer Pressure-High .7.5 4.81 1.0 s 2385 psig s 2390.2 psig 11. Pressuriier Water Level-High 8.0 2.14-2.0 s 92% ofinstrument ~ s 92.7% ofinstrument span-span 1.6% AT_ span for AT,0.6% AT span for Pressurizer Pressure. NA - Information not applicable NWS - Value not within Westinghouse scope - see TVA ca!culations i D0161:1D.022690 A-4 ..2.-. a

WESTINGHOUSE CLASS 3 TABLE 2.2-1 (continued) REACTOR TRIP SYSTEM INSTRUMENTATION TRIP SETPOINTS Total Sensor Functional Unit Allowance (TA) _Z_ Drift (S) Trio Setpoint Allowable Value 12. Lossof Flow 2.8 2.14 0.6 2 90% of loop design 2 89.4% of loop design flow

• flow" 13.

Steam Generator Water Level-Low-Low a. Vessel AT Equivalent to Power 6.0 2.39 1.6 Vessel ATvariableinput Vessel ATvariableinput s 50% RTP s 50% RTP s tripsetpoint + 2.5% RTP Coincidentwith ~ 5 team Generator Water 16.9 15.44 2.0 216.9% of Narrow Range 216.3% of Narrow Range Level-Low-Low (Adverse) Instrument span Instrument span and Containment Pressure-EAM 4.4 2.94 1.5 's 0.5 psig so.6 psig or Steam Generator Water 13.0 11.54 2.0. 213.0% of Narrow Range 212.4% of Narrow Range - Level-Low-Low (EAM) Instrument span Instrument span With a time celay (Ts) sT (Note 5) s(1.01) T,(Note 5) 3 if one Steam Generator is affected or A Time Delay (Tm)if two or 5Tm (Note 5) s(1.01) Tm (Note 5) more Steam Generators are affected

• Loop desgn flow = 91 A00 GPM 00161:1D/022690 A-5

..,-~..+..-~w a s c

a.- i v WESTINGHOUSE CLASS 3 TABLE 2.2-1 (continued) REACTOR TRIP SYSTEM INSTRUMENTATION TRIP SETPOINTS Total Sensor Functional Unit Allowarxe (TA) Z_ Drift (5) Trio Setpoint Allowable Value. b. Vessel AT Equivalent to Power >50% RTP Coincident with Steam Generator Water 16.9 15.44 2.0 216.9% of Narrow Range 216.3% of Narrow Range Level-Low-Low (Adverse) Instrument span Instrument span and Containment Pressure-EAM 4.4 2.94' 1.5 s0.5 psig s0.6 psig of Steam Generator Water 13.0 11.54 2.0 213.0% of Narrow Range 212.4% of Narrow Range Level-Low-Low (EAM) Instrument span instrument span 14. Undervoltage - Reactor NWS NWS NWS 2 5022 volts 2 NWSvolts Coolant Pump l 15. Underfrequency-Reactor 3.33 0.0 0.0 2 56 Hz 2 55.9 Hz Coolant Pumps 16. Safety injection input NA NA NA NA NA from ESF NWS - Value not withm Westenghouse scope - see TVA cakulations. D0161:10.022690 A-6 ~ ~.,.

WESTINGHOUSE CLASS 3 TABLE 2.2-1 (continued) REACTOR TRIP SYSTEM INSTRUMENTATION TRIP SETPOINTS Total Sensor Functional Unit Allowance (TA) _Z_ Drift (S) Trio Setpoint Allowable Value 17. Reactor Trip 5ystem interlocks

a. Intermediate Range NWS NWS NWS 2 1x10-10 amps 2 NWSamps Neutron Flux, P-6

b. Low Power Reactor Trips Block, P-7

1) P-10 input NA NA NA Nominal 10 percent of s 12.4 percent of kated Thermal Power Rated Thermal Power I

2) P-13 Input NA NA NA Nominal 10 percent s 17.4 percent Turbine

. Turbine Impulse impulse Pressure Pressure Equivalent Equivalent

c. Power Range Neutron NA NA NA s 35 percent of Rated 5 37.4 percent of Thermal Power Rated Thermal Power Flux, P-8

d. Power Range Neutron NA NA NA Nominal 10 percent of 2 7.6 percent of Flux, P-10 Rated Thermal Power Rated Thermal Power -

e. Turbine impulse Chamber NA NA NA Nominal 10 percent s 12.4 percent Turbine -

Pressure, P-13 . Turbine impulse . Impulse Pressure Pressure Equivalent Equivalent

f. Reactor Trip, P-4 NA NA NA NA NA

g. Power Range Neutron

'NA NA NA-

2. 50% RTP 2 52.4% RTP Flux, P-9 NWS - Value not within Westinghouse scope.- see TVA calculations ^

A-7 D0161:10.022690 - s - * ~... . - - - ~. ~ -

WESTINGHOUSE CLASS 3 } TABLE 2.2-1 (Contmoed) REACTOR TIWP SYSTEM INSTRUMENTATION TIWP SETPOINTS NOTATION 1 + t,S 1 + t,S NOTE 1: Overtemperature AT ( 1 + t S ) s ATg {K - K, ( 1 + tp) (T-T*1 + K (I'-I")- f,(AI)} 8 3 3 Where: 1+tS 4 Lead-lagmmpensatoron measured AT = 1+tb s Time constants utilized in the lead -lag antroller for AT, t, = 12 secs,1 = 3 secs. = t,, t3 3 Indicated ATat RATEDTIIERMAL POWER AT = g 1.15 K, = K = 0.011 2 1 + t,S The runction generated by the lead -la g controller fort dynamiccompensation = 1+t8 2 D0161:1D,922690 A-8

WESTINGHOUSE CLASS 3 TABLE 2.2-1 (Continued) REACTOR TRIP SYSTEM INSTRUMENTATION TRIP 5ETPO6NT5 NOTATION NOTE 1: (continued) Time constants utilized in the lead-lag controller for T,y. : = 33 secs, 32 = 4 secs. ti, t2 = Average temperature'F T = T* 5 578.2*F (Nominal Tagat RATED THERMAL POWER) = 0.00055 K3 = Pressurizer pressure, psig P = 2235 psig (Nominal RCS operating pressure) P' = Laplace transform operator 5 = and f (at)is a function of the indicated difference between top and bottom detectors of the power range nuclear ion chamber; with i gains to be selected based on measured instrument response during plant startup tests such that: for qt - qb between -29 percent and + 5 percent f (AI) = 0 (where qt and qb are percent RATED THERMAL POWER in the top (i) i and bottom halves of the core respectively, and qt + qb is total THERMAL POWER in percent of RATED THE RMAL POWER). (ii) for each percent that the magnitude of (qt - qb) exceeds -29 percent, the AT trip setpoint shall be automatically reduced by 1.50 percent of its value at RATED THERMAL POWER. r (iii) for each percent that the magnitude of (qt - qb) exceeds + 5 percent, the AT trip setpoint shall be automatically reduced by 0.86 percent of its value at RATED THERMAL POWER. 00161:10 922690 A-9 a e n-- a- -+s. n <,,, +. ,ec w.w..- -e-. v--, -,,,, ,w.,- ,,,.. ~ - - -,

WESTINGHOUSE CLASS 3 TABLE 2.2-1 (Contmued) REACTOR TRIP SYSTEM INSTRUMENTATION TRIP SETPOINTS NOTATION NOTE 2: The channel's maximum trip setpoint shall not exceed its computed trip point by more than 1.9 percent AT span. 1 + t,S t5 3 NOTE 3: Overpower AT ( 1 + cp ) s ATg {K - K ( 1 + t S) T-K tT-T*l-f,(Ali) 4 3 3 3 Where: I + t,S asdefined in Note 1 = 1+tS 3 asdefined in Note 1 t,, t3 = AT = asdefined in Note 1 g K, = 1.087 K = 0.02/F forincreasing average temperature and 0 fordecreasing average temperature 3 I+tp The function genera ted by the lead -la g controller fort dynamiccompenetion = 1 +1 S 3 t, Time consta nt utilized in the lead -lag controi*er fort, t, = 10 secs = 00161:10 022690 A-10 i h

WESTINGHOUSE CLASS 3 TABLE 2.2-1 (Contmued) REACTOR TRIP SYSTEM INSTRUMENTATION TRPP SETPOINTS NOTATIOtt NOTE 3: (continued) K6 = 0.0011/7 for T > T* and Ks = 0 for T s T-T as defined in Note 1 = T" Indicated T.,9at RATED THERMAL POWER (calibration temperature for aT instrumentation, s 578 2*F) = 5 as defined in Note 1 = i f (al) 0 for all at 2 = NOTE 4: The channel's maximum trip setpoint shall not exceed its computed trip point by more than 1.7 percent AT span. NOTE 5: Steam Generator Water Level - Low-tow Trip Time Delay {A1(P)' + A2(P)'- A3(P) + A4} {0.99} Ts = {B1(P)' + B2(P)'-B3(P) + B4} {0.99} Tu = Where: Vessel AT Equivalent to Power (% RTP), Ps50% RTP. P = Time delay for Steam Generator Water Level-Low-Low Reactor Trip, one Steam Generator af fxted. Ts = Time delay for Steam Generator Water Level-Low-Low Reactor Trip, two or more Steam Generators af fected. Tu = -0.00583 B1 = A1 = -0.00532 + 0.735 B2 = + 0.678 A2 = A3 + 33.560 B3 + 31.340 = = + 649.5 84 = A4 = + 58*.5 - . 00161:10 922690 A-11 m w .m. = .c .,i m vw. ...~e.,,

WESTINGHOUSE CLASS 3 2.2 LIMITING SAFETY SYSTEM SETTINGS I BASES 1 2.2.1 REACTOR TRIP SYSTEM INSTRUMENTATION SETPOINTS ) The Reactor Trip Setpoint Limits specified in Table 2.21 are the nominal values at f which the Reactor Trips are set for each functional unit. The Trip Setpoints have been selected to ensure that the reactor core and reactor coolant system are [ prevented from exceeding their safety limits during normal operation and design basis anticipated operational occurrences and to assist the Engineered Safety Features Actuation System in mitigating the consequences of accidents. The i setpoint for a reactor trip system or interlock function is considered to be adjusted consistent with the nominal value when the "as measured" setpoint is within the band allowed for calibration accuracy. To accommodate the instrument drift assumed to occur between operational tests and the accuracy to which setpoints can be measured and calibrated,' Allowable r Values for the reactor trip setpoints have been specified in Table 2.21. Operation with setpoints less conservative than the Trip Setpoint but within the Allowable Value is acceptable since an allowance has been made in the safety analysis to accommodate this error. An optional provision has been included for determining the OPERABILITY of a channel when its trip setpoint is found to exceed the Allowable Value. The methodology of this option utilizes the "as measured" deviation from the specified calibration point for rack and sensor components in conjunction with a statistical combination of the other uncertainties in calibrating the i instrumentation. In Equation 2.21, Z + R + S s TA, the interactive effects of the errors in the rack and the sensor, and the "as measured" values of the errors are considered. Z, as specified in Table 2.21, in percent span, is the statistical summation of errors assumed in the analysis excluding those associated with the sensor and rack drift and the accuracy of their measurement. TA or Total Allowance is the difference, in percent span, between the trip setpoint and the value used in the analysis for reactor trip. R or Rack Error is the "as measured" deviation, in percent span, for the affected channel from the specified trip setpoint. S or Sensor Drift is either the "as measured" deviation of the sensor from its calibration point or the value specified in Table 2.21,,in percent span, from the 4 00:01:10 022690 A 12

WESTINGHOUSE CLASS 3 analysis assumptions. Use of Equation 2.2-1 allows for a sensor drift factor, an increased rack drift factor, and provides a threshold value for reportability. The methodology to derive the trip setpoints is based upon combining all of the uncertainties in the channels. Inherent to the determination of the trip setpoints are the magnitudes of these channel uncertainties. Sensors and other instrumentation utilized in these channels are expected to be capable of operating within the allowances of these uncertainty magnitudes. Rack drift in excess of the Allowable Value exhibits the behavior that the rack has not met its allowance. Being that there { is a small statistical chance that this will happen, an infrequent excessive drift is expected. Rack or sensor drift, in excess of the allowance that is more than occasional, may be indicative of more serious problems and should warrant further investigation, i i i l-o0161:1o'022690 A 13 l ?

e WESTINGHOUSE CLASS 3 l j 3/4.3.2 ENGINEERED SAFETY FEATURE ACTUATION SYSTEM l INSTRUMENTATION t LIMITING CONDITION FOR OPERATION i 7 3.3.2 The Engineered Safety Feature Actuation System (ESFAS) instrumentation channels and interlocks shown in Table 3.3-3 shall be OPERABLE with their Trip f Setpoints set consistent with the values shown in the Trip Setpoint column of Table 3.3 4 and with RESPONSE TIMES as shown in Table 3.3 5. APPLICABILITY: As shown in Table 3.3 3. ACTION: a. With an ESFAS Instrumentation or Interlock Setpoint Trip less conservative than the value shown in the Trip Setpoint column but more conservative than the value shown in the Allowable Value column of Table 3.3-4 adjust the Setpoint consistent with the Trip Setpoint value. b, With an ESFAS Instrumentation or Interlock Trip Setpoint less conservative than the value shown in the Allowable Value column of Table 3.3 4, either: 1. Adjust the Setpoint consistent with the Trip Setpoint value of Table 3.3-4 and determine within 12 hours that Equation 2.21 was satisfied for the affected channel, or 2. Declare the channel inoperable and apply the applicable ACTION statement requirements of Table 3.3.3 until the channel is restored to OPERABLE status with its Setpoint adjusted consistent with the Trip Setpoint value. EQUATION 2.21 Z + R + S s TA where: Z The value for Column Z of Table 3.3-4 for the affected channel, = Do161:Io'022690 A 14

WESTINGHOUSE CLASS 3 i r R = The "as measured" value (in percent span) of rack error for the affected

channel, S

=. Either the,"as measured" value (in percent span) of the sensor error, or the value from Column S (Sensor Drift) of Table 3.3-4 for the affected -i channel, and TA = _ The value from Column TA (Total Allowance) of Table 3.3-4 for the affected channel. 'l e Ih r . h + 3 h I f -} r = s 00161:10 022690 A 15 i i w + - -,

WESTINGHOUSE CLASS 3 TASLE 3.3-4 ENGNEERED SAFETY FEATURE ACTUATION SYSTEM TRIP SETPOINTS Total Sensor Functional Unit Allowance (TA)

_Z_,

Drift (5) Trio Setpoint Allowable Value 1. SAFETY INJECTION, TURBINE TRIP AND FEEDWATER ISOLATION A. ManualInitiation NA NA NA NA NA B. Automatic Actuation Logic NA NA NA NA NA C Containment Pressure-High 5.5 3.44 1.5 s 1.54 psig s 1.6 psig D. Pressurizer Pressure-Low 17.5 14 26 2.0 21870 psig 2 1864.8 psig E. Steamline Pressure-Low 13.9 11.27 1.8 2 600 psig (Note 1) 2 592.2 psig (Note 1) 2. CONTAINMENT SPRAY A. ManualInitiation NA NA NA NA NA B. Automatic Actuation Logic NA NA NA NA NA C. Containment Pressure-5.5 3.44 1.5 s 2.81 psig s 2.9 psig High-High 3. CONTAINMENT ISOLATION A. Phase "A" Isolation

1. Manual NA NA NA NA NA

2. From 5afety injection NA NA NA NA NA Automatic Actuation Logic S.

Phase "B" Isolation

1. Manual NA NA NA NA NA

2. Automatic Actuation NA NA NA NA NA

3. Containment Pressure-5.5 3.44 1.5 s 2.81 psig s 2.9 psig High-High D0161:1D422690 A-16 w

WESTINGHOUSE CLASS 3 TABLE 3.3-4 (continued) ENGNEERED SAFETY FEATURE ACTUATION SYSTEM TRIP SETPOINTS Total Sensor Functional Unit Allowance (TA) Z Drift (5) Trip 5etpoint Allowable Value C. Containment Ventilation isolation

1. Manual NA NA NA NA NA

2. From 5afety injection NA NA NA NA NA Automatic Actuation Logic 4

STEAM LINE ISOLATION A. Manual NA NA NA NA NA B. Automatic Actuation NA NA NA NA NA C. Containment Pressure-5.5 3.44 1.5 s 2.81 psig s 2.9 psig High-High D. SteamlinePressure-Low 13.9 11.27 1.8 2 600 psig (Note 1) 2 592.2 psig (Note 1) - E. Negative Steamline Pressure ' 2.0 0.25 00 s 100.0 psi (Note 2) 5107.8 psi (Note 2) Rate-High 5. TURBINE TRIP AND FEEDWATER ISOLATION A. SteamGeneratorWater 12.2 11.03 2.0 s 81.0% of narrow range s 81.7% of narrow range Level-High-High instrument span instrument span 6. AUXILIARY FEEDWATER ' A. Steam GeneratorWater Level-Low-Low 1. Vesse! AT Equivalent to 6.0 2.39 1.6 Vessel ATvariableinput Vessel ATvariableinput Power s 50% RTP s 50% RTP s tripsetpoint + 2.5% RTP DO M1:1DS21690 A-17 a a. .1. m.. m mr-m a -m.e m -- -. - w1 -==,-..__.- m--m.--vw + -~~. ~.. + o~-

1 I WESTINGHOUSE CLASS 3 TABLE 3.3-4 (continued) ENGINEERED SAFETY FEATURE ACTUATION SYSTEM TRIP SETPOtNTS Total Sensor Functional Unit Allowance (TA) Z. Drift (5) Trio Setpoint Allowable Value Coincident with Steam Generator Water 16.9 15.44 2.0 216 9% of Narrow Range 216 3% of Narrow Range Level-Low-Low (Adverse) Instrument span Instrument span and Containment Pressure-4.4 2.9 1.5 s 0.5 psig s 0.6 psig EAM or Steam Generator Water 13.0 11.54 2.0 213.0% of Narrow Range 212.4% of Narrow Range Level-Low-tow (EAM) Instrument span Instrument span With a time delay (T ) sT (Note 5 Table 2.2-1) s(1.01) T,(Note 5 3 3 if one Steam Generatoris Table 2.2-1) J affected or A Time Delay (Tm) sT (Note 5 Table 2.2-1) 5(1.01) Tm (Note 5 if twoormoreSteam Table 2.2-1) Generators are affected 2. Vessel sT Equivalent to Power >50% RTP Coincident with steam Generator Water 16.9 15.44 2.0 216.9% of Narrow Range 216.3% of Narrow Range level-Low-Low (Adverse) Instrument span instrument span and Containment Pressure-4.4 2.9 1.5 s0.5 psig s0.6 psig EAM D0161:10922690 A-18

WESTINGHOUSE CLASS 3 TABLE 3.3-4 (continued) ENGINEERED SAFETY FEATURE ACTUATION SYSTEM TR8P SETPOtNTS Total Sensor Functional Unit Allowance (TA) Z Drift (5) Trio Setpoint Allowable Value or Steam Generator Water 13.0 11.54 2.0 213.0% of Narrow Range 212.4% of Narrow Range Level-tow-Low (EAM) instrument span Instrument span B. Safety injection see 1 above(all sisetpoints) C. Station Blackout D. Tripsof MainFeedwater NA NA NA NA NA Pumps 7. ENGINEERED SAFETY FEATURES ACTUATION 5YSTEM INTERLOCK 5 A. Pressurizer Pressure NOT-P-11 NA NA NA Nominal 1970 psig s 1975.2 psig B. Pressurizer Pressure NA NA NA Nominal 1970 psig 21964 8 psig P-11 C. Reactor Trip, P-4 NA NA NA NA NA Note 1: Time constants utilized in the lead 4ag controller for Steam Pressure-Low are t 2 50secondsand ty 5 5 seconds. Note 2: Time constant utilized in the rate-lag controller for Negative Steamline Pressure Rate-High is t 2 50 seconds. A-19 00161;10 o 22690

\\ WESTINGHOUSE CLASS 3 TABLE 3.3-4 (continued) ENGINEERED SAi'ETY FEATURE ACTUATION SYSTEM TRtr SETPO6NTS Total 5ensor Functional Unit Allowance (TA) Z Drift (5) Trip Setpoint Allowable Value 8. AUTOMATIC 5WITCHOVER TO CONTAINMENT SUMP A. RWST Level-Low NWS NWS NWS 130" from tank base NW5 COINCiDENTWITH NWS NWS NWS 30" above elev. 680* NWS Containent Sump Level-High AND Safety injection (see 1 above for all safety injection setpointst Allowable Value) NWS - Value not within Westinghouse scope - see TVA calculation 00161:10922690 A-20 C_. _ _ _ _ _ _. _ _ -_

x;u --- rewg 1 I k f 4 i 1 1 [ s' 's f ] 1'. i I i e i I I4 t 1 8 e I } J f i e l )* t b .f I ? 1 J I i } i i t i i } f 6 .c i ) i e i e l' 8 I t i I f 5 N'. EL

WESTINGHOUSE CLASS 3 3/4.3 INSTRUMENTATION BASES l 3/4.3.1 and 3/4.3.2 R_EACTOR TRIP AND ENGINEERED SAFETY FEATURE ACTUATION SYSTEM INSTRUMENTATION The OPERABILITY of the Reactor Protection System and Engineered Safety Feature Actuation System Instrumentation and interlocks ensure that 1) the associated action and/or reactor trip will be initiated when 'Se parameter monitored by each channel or combination thereof reaches its setpoint 2) the specified coincidence logic is maintained,3) sufficient redundancy is maintained to permit a channel to be out of service for testing or maintenance, and 4) sufficient system functional capability is available from diverse parameters. The OPERABILITY of these systems is required to provide the overall reliability, I redundancy, and diversity assumed available in the facility design for the protection and mitigation of accident and transient conditions. The integrated operation of i each of these systems is consistent with the assumptions used in the accident analyses. The surveillance requirements specified for these systems ensure that the overall system functional capability is maintained comparable to the original design standards. The periodic surveillance tests performed at the minimum frequencies are sufficient to demonstrate this capability. The Engineered Safety Feature Actuation System Instrumentation Trip Setpoints specified in Table 3.3-4 are the nominal values at which the bistables are set for each functional unit. A setpoint is considered to be adjusted consistent with the nominal value when the "as measured" setpoint is within the band allowed for calibration accuracy. To accommodate the instrument drift assumed to occur between operational tests and the accuracy to which setpoints can be measured and calibrated, Allowable Values for the setpoints have been specified in Table 3.3 4 Operation with j setpoints less conservative than the Trip Setpoint but within the Allowable Value is acceptable since an allowance has been made in the safety analysis to accommodate this error. An optional provision has been included for determining D0161:1 D'022690 A 21 .. l

WESTINGHOUSE CLASS 3 the OPERABILITY of a channel when its trip setpoint is found to exceed the f Allowable Value. The methodology of this option utilizes the "as measured" deviation from the specified calibration point for rack and sensor components in conjunction with a statistical combination of the other uncertainties of the 4 instrumentation to measure the process variable and the uncertainties in calibrating the instrumentation. In Equation 2.21, Z + R + S s TA, the interactive effects of 1 the errors in the rack and the sensor, and the "as measured" values of the errors are considered. Z, as specified in Table 3.3-4, in percent span, is the statistical summation of errors assumed in the analysis excluding those associated with the l sensor and rack drift and the accuracy of their measurement. TA or Total Allowance is the difference,in percent span, between the trip setpoint and the value { used in the analysis for the actuation, R or Rack Error is the "as measured" deviation, in percent span, for the affected channel from the specified trip setpoint. 5 or Sensor l Drift is either the "as measured" deviation of the sensor from its calibration point or the value specified in Table 3.3 4,in percent span, from the analysis assumptions. Use of Equation 2.21 allows for a sensor drift factor, an increased rack drift factor, and provides a threshold value for reportability. i 4 The methodology to derive the trip setpoints is based upon combining all of the uncertainties in the channels. Inherent to the determination of the trip setpoints are the magnitudes of these channel uncertainties. Sensor and rack instrumentation utilized in these channels are expected to be capable of operating within the allowances of these uncertainty magnitudes. Rack drift in excess of the Allowable Value exhibits the behavior that the rack has not met its allowance. Being that there is a small statistical chance that this will happen, an infrequent excessive drift is expected. Rack or sensor drift,in excess of the allowance that is more than occasional, may be indicative of more serious problems and should warrant further ] investigation. 9 O l l 00161:1D'022090 A 22 i i . -.}}