ML20064N328

Rev 0 to Operating Parameter Uncertainties for Byron/ Braidwood Revised Thermal Design Procedure

ML20064N328
Person / Time
Site:	Byron, Braidwood
Issue date:	12/20/1993
From:	Vandevisse P, Wicyk P WESTINGHOUSE ELECTRIC COMPANY, DIV OF CBS CORP.
To:
Shared Package
ML19304B887	List: ML20064N257 ML20064N272 ML20064N321 ML20064N328 ML20064N341
References
PROC-931220, NUDOCS 9403290261
Download: ML20064N328 (27)

Text

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ATTACHMENT 7 Operating Parameter Uncertainties for the Byron /Braidwood Revised Thermal Design Procedure Westinghouse Proprietary Class 3 9403290261 DR 940323 '

ADOCK 05000454 PDR

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WESTINGHOUSE PROPRIETARY CLASS 3' 1

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OPERATING PARAMETER UNCERTAINTIES for the BYRON /BRAIDWOOD REVISED THERMAL DESIGN PROCEDURE ~

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Revision 0 December 20, 1993 P.J. Wicyk ,

P. VandeVisse  ;

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- Conanonwealth Edison Company I Nuclear Engineering and Technology Services

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WESTINGHOUSE PROPRIETARY CLASS 3 COMMONWEALTH EDISON COMPANY TABLE OF CONTENTS SECTION TITLE PAGE I. Introduction . . . . . . . . . . . . 1 II. Methodology . . . . . . . . . . . . . 2 III. Instrument Channel Uncertainties . . 6 IV. Conclusion . . . . . . . . . . . . . 17 References . . . . . . . . . . . . . 18

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WESTINGHOUSE' PROPRIETARY CIASS'3'

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5. o, LIST OF TABLES 4

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TABLE TITLE PAGE 4 1 Pressurizer Pressure Control . . . . . 8 System Accuracy 2 Tavg - Rod Control Channel Accuracy . . 10 3 Reactor Power Calorimetric Accuracy . . 15 4 Reactor Power Sensitivities . . . . . . 15 f

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WESTINGHOUSE PROPRIETARY CLASS 3

, , - COMMONWEALTH EDISON COMPANY OPERATING PARAMETER' UNCERTAINTIES for the BYRON /BRAIDWOOD REVISED THERMAL DESIGN PROCEDURE I. Introduction The Revised Thermal Design Procedure (RTDP) determines the uncertainties of four process parameters used to establish bounding process conditions for various analyses. These parameters are Pressurizer Pressure, Primary Coolant Temper-ature (T3 ya), Reactor Power and Reactor Coolant System Flow.

Pressurizer Pressure uncertainty results from'the 7300 process control system. uncertainties associated with the pressurizer pressure control system. Tg ya uncertainty re-o sults from the 7300 process control system uncertainties associated with the rod control channel. Reactor Power.is obtained from daily power calorimetric calculated by the plant process computer. Uncertainty in Reactor Power're-sults from the uncertainty in the process parameters _that provide inputs to the plant process computer. Reactor Coolant System (RCS) Flow is obtained from the normalization of the RCS Cold Leg elbow taps to a precision flow calori-metric at the beginning of each cycle.

The uncertainty calculations for these process parameters are based on:

Review of Byron and Braidwood station instrument chan-nel cal..bration procedures.

Existing environmental effects and current as-built conditions that potentially effect the instrument channel accuracies.

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WESTINGBOUSE PROPRIETARY CLASS 3;

. C0tedONNEALTH EDISON COMPANY Accuracy of measurement and test equipment- (MTE) 'used by the Byron and Braidwood stations for calibration of the instrument channels.

Sensitivity determination of the daily power'calorimet-

,_. ric algorithm currently installed on the Byron and Braidwood stations plant process computers.

II. Methodology

- The methodology used to determine the accuracy of the pro-cess parameters combines random and bias errors to determine a total error for the parameter. Random errors (a) are considered to be normally distributed and statistically independent. Based on references 1 and 2 and various indus  :

try standards (references 12 and 13), random errors ~are combined using the square root of the sumLof the squares.

Bias errors (e) are combined arithmetica11y. The total e

random error is multiplied'by 2 to ensure a 95% confidence value and combined with the total bias error to obtain.a total error.

Total Error = 2{(202)1/2) + Ee For the pressurizer pressure process errors, the~1oop accu-racy analysis considers the pressurizer pressure signal and the process controller errors. The pressurizer pressure signal accuracy was previously determined in reference'5 and.

used a methodology consistent with the Westinghouse method-ology in' reference 3. The loop accuracy is determined by an equation of'the form:

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WESTINGHOUSE PROPRIETARY CLASS 3 COMMONWEALTH EDISON COMPANY loop accuracy = (EMA2 + pgg2 + (SCA + SMTE +SD)2 ,

SPE2 + STE2+ (RCA + RMTE + CA + RD) 2 + RTE2 ) 1/2 +

TI The parameters are described in references 3 and 5 and are briefly described below.

Process Measurement Allowance (PMA) - allowance for non-instrument related effects which have a direct bearing on the accuracy of an instrument channel's reading, e.g. temperature stratification in a large diameter pipe.

Primary Element Accuracy (PEA) - error due to the use of a metering device, e.g. venturi, orifice, or elbow.

Typically, this is a calculated or measured accuracy for the device.

Sensor Calibration Accuracy (SCA) - the reference (calibration) accuracy for a sensor or transmitter as defined by SAMA Standard PMC 20.1-1973.

Sensor Maintenance & Test Equipment (SMTE) - the accu-racy of the test equipment (typically a high accuracy local readout gauge and DVM) used to calibrate a sensor or transmitter in the field or in a calibration labora-tory.

Sensor Drift (SD) - the change in input-output rela-tionship over a period of time at reference calibration conditions, e.g., at constant temperature.

Sensor Pressure Error (SPE) - the change in. input-out-put relationship due to a change in the static head pressure from the calibration conditions (if calibra-

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i tion is performed atL11ne pressure) or the. accuracy to. H which a correction factor'is introduced for the dif - -'

ference between calibration and operating co'nditions for a Ap transmitter.

Sensor Temperature Error (STE) - the change.in input-output relationship due to a change in the: ambient _-

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temperature (for expected normal operating conditions);

from the reference calibration conditions about'a transmitter.

Rack Calibration Accuracy (RCA) - the reference'(cali-bration) accuracy, as defined by SAMA Standard PMC 20.1-1973 for a, process loop string.

Rack Maintenance & Test Equipment (RMTE) - the. accuracy of the test equipment (typically a transmitter simula-tor, voltage or current power supply,-and DVM) used to calibrate a process loop in the racks- .

Controller Accuracy (CA) - the' calibration accuracy for the proportional controller.

Rack Drift (RD) - the change in input-output relation-ship over a period of time at reference conditions, e.g. at constant temperature.

Rack Temperature Effect (RTE) - change in input-output '

relationship for the process rack module string due to a change in the ambient' temperature from the reference calibration conditions.

Thermal' Inertia (TI) - allowance for the interaction of-pressurizer heaters and spray.

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4 WESTINGEOUSE PROPRIETARY CIASS'3~

., -COMMONNEALTE EDISONiCOMPANY.

. For the -TA yg and power range process . errors, the loop accu-racy analysis performed to determine the total error is based on references 1 and 2. The Normal ~ Loop Error (NLE).

term is obtained from evaluation of the following:

i Instrument Reference Accuracy (RA) - The limit that an instrument measurement error should not exceed when a .;

device is used under manufacturer's specified or refer-ence operating conditions. A manufacturer may. define this value to bound the effects of linearity, hysteresis, deadband, and repeatability.

Calibration Error (CAL) - TheLerror resulting from calibration methods, calibration components, measure-ment and test equipment (MTE) reference accuracy and measurement and test equipment reading error.

Setting Tolerance (ST) - The-inaccuracy of offset introduced into the calibration' process due to proce-dural allowances given to technicians performing the calibration.

Normal Operating Errors (Een) - The summation of the non-random,. deterministic errors. An error is.non-random if its value can be related to specific environ- ~

mental or operational conditions. Non-random errors u can be further classified as symmetric or as a bias.

Symmetric non-random errors are predictable in magni '

tude, but not in sign. Bias errors are predictable in ]

both sign and magnitude. l l

As shown in reference 2, the following is a list of -

f typical-non-random errors that are evaluated in the determination of instrument setpoint and control'chan- .

nel accuracies.

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, Non-random Error Source- Type Density errors bias Process Measurement' errors bias Flow element errors symmetric '

Temperature, Humidity, rad- bias or symmet-iation, seismic and insula- ric (depending.

tion resistance errors on specific

source)

. Thermal expansion errors bias. "

Configuration errors symmetric Drift symmetric (without specific testing)

Static pressure error bias.

Power supply error symmetric The determination of the random error is defined by:

o= (RA2 + CAL 2 + ST2+C INPUT I where: the RA, CAL and ST are as-described above.

The term oINPUT represents ' random errors that are present at the input to the instrument module or instrument channel.

The calibration error (CAL) is further defined as: I 2 2 2 2 CAL = (MTE IN + STD IN + MTE 0UT + STD 0UT)  !

1 where: MTE (measurement and test equipment error) -

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the inaccuracy introduced into the calibra-tion process due to the accuracy of the mea-surement and test' equipment used.to calibrate the instrument module or channel. .

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STD (calibration standard' error) the'1nac-

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curacy introduced ~into the calibration pro-

, cess due to the- accuracy of'thecstandards used to calibrate the measurement and test equipment.

A detailed explanation of the above methodology and error J

terms is provided in reference 2.

III. Instrument Channel Uncertainty The determination of the four process channel uncertainties for the Byron and Braidwood stations is discussed in the following sections.

1. Pressurizer Pressure Pressurizer pressure is controlled by. comparing a reference pressure setpoint to the measured pressurizer pressure.

Uncertainties are evaluated for the pressure-sensing instru e mentation and the process control ~ instrumentation'. The.

uncertainties are combined, as described in.section II, '

using a methodology consistent with'the Westinghouse method-ology. As shown in table 1, the channel uncertainty is 3.76% span which corresponds to an accuracy of 130.0 psi.

Per reference 114, an additional allowance of ( ]+a,e is made for the thermal inertia (pressure overshoot or under-shoot) due to the interaction of the heaters and sprays.

Assuming a normal, two sided' probability-distribution,.the-total channel uncertainty at a 95% confidence level is

( . ]+8'C.

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. TABLE 1 PRESSURIZER PRESSURE'CONTRCL SYSTEM ACCURACY

' Sensor Uncertainties SCA =.0.50% span SMTE = 1.00% span +3,c_ .

STE =

SPE =

SD =_ _

Process Rack and Controller Uncertainties a

Controller CA = 0.50% span

) -Controller RMTE = 0.65% span Driver RCA = 0.50% span Driver RMTE = 0.18% span Process Rack RCA = 0.50% span Process Rack RMTE = _0. 7 6% span +a, c Process Rack RD =

Process Rack RTE' =

Bias =_ _

The channel uncertainty equation is:

_ _ +a,e

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2. TAVG (rod control channel)

T3 yg is controlled by comparing a reference temperature setpoint (obtained from the turbine impulse chamber pressure and power range flux signals) and1 the auctioneered high.T 3ya signal from the narrow range Tg and Tc signals. Uncertain-ties are evaluated for the RTD's and T yg g . process. errors (reference 6), the turbine impulse pressure process errors (reference 7) and the rod control process errors (reference

9) . The uncertainties are combined using the methodology described-in section II. As shown in' table 2, the total error for the process signal is i3.02 F random and 1.14*F bias.

Per reference 4, Westinghouse has determined that the con-troller deadband is represented by a uniform distribution-where there is an equal probability.throughout the range'of the deadband. The variance of a f4*F deadband;is represent-ed by:

2 (0o3) 2 = (R ) /12 = 5. 33

• F '

Combining the variance for the process signal and the deadband results in a controller variance of:

c 2, gyp)2 + (ogg)2 = (3. 02) 2 + 5.33 = 14. 4 5* F The total channel accuracy is obtained by combining the T xyc standard deviation (o) of 3.80*F and the 1.14*F bias.

. Assuming a normal, two sided probability distribution, this results in an uncertainty of 8.74 *F at a 95% confidence level.

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WESTINGBOUSE' PROPRIETARY CLASS 3'

. COMMONWEALTH-EDISON COMPANY TABLE 2 TAVG - ROD CONTROL' CHANNEL ACCURACY TURBINE ROD CONTROL' CALIBRATION. MODULE IMPULSE UNCERTAINTY

• PRESSURE 1 2 3 4 5 RA 0.10% 0.58% 0.14% 0.13% 0.13% .0.46%

CAL 0.14% 0.26% 0.07% 0.09%. 0.09% 1.84%

ST 0.17% 0.33% 0.17% 0.17% 0.17%. 0.17%

oINPUT 0.89% 1.65% 0.28% 0.85% 0.88% 19.93%

In percent span BIAS: Bulk Avg. Temp. =[

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Turb. Imp. Press

= 0.92% span Channel Total Error (a) = 3.02*F random

= 1.14

• F bias Deadband (o2 ) = 5.33*F random At a 95% confidence level, the total uncertainty for the TAyg instrument channel is:

2 [ ( (3. 02

• F) 2 + (5. 33

• F) } 1/2) + 1,14*F = i8.74*F Page 10

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3. Reactor Power Byron and.Braidwood are required to determine reactor power-to be in compliance with the-station Technical Specifica-tions. Reactor power is determined by a secondary power calorimetric that is computed by the-plant process computer.

The plant process computer determines reactor power level from values for instantaneous and time ave' raged signals using inputs from the following instrument channels:

Feedwater Flow (FF) : differential pressure across'the feedwater venturies is providea to the process comput-er. The daily power calorimetric algorithm uses the flow coefficients for each venturi to determine:

feedwater flow.

Feedwater Temperature-(FT): thermocouple input is provided to the process computer.

Steam Pressure (SP) : a steam'line pressure signal from the process control system is provided to the process computer.

Blowdown Flow ('BF) : blowdown flow orifice differential pressures are measured, converted to flow and provided.

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to the process computer.

Tempering Line Flow (TF) : tempering line flow orifice differential pressures are measured, converted'to flow and provided to the process computer. The daily power-calorimetric algorithm combines feedwater flow and tempering line flow to determine total feedwater flow. .

In addition, the Power Range Neutron Flux channels are required to be adjusted when the difference between the indicated neutron flux power level'and the reactor power -

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determined.by the daily power calor'imetric is greater than i

that allowed by the Technical Specifications. This differ- .l 1

ence is effected by the accuracy of the reactor thermal

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l power calculated by the daily power calorimetric which is dependent on:

1) The process instrument channel uncertainties for-each of the process computer inputs.- These uncer-tainties are determined using the methodology described in section II. The uncertainty of each-process parameter is shown in tdble 3. Determi-nation of-the uncertainties assumes that the plant +

is at 100% reactor thermal power .(RTP) when the daily power calorimetric is performed. At~1ower power levels, the increased measurement uncertain-ty is more than compensated for by the increased margin to DNB.

2) The.effect of the process' input uncertainties on. '

the daily power calorimetric algorithm. Table 4 ,

lists the sensitivities.and relationship of each process error. It should be noted that an' allow-ance for venturi fouling is not included'since this uncertainty is accounted for in,the station Technical Specifications.

The daily power range calorimetric. algorithm determines '

reactor power from a. heat balance across.the steam genera-tor. Assuming that the primary and secondary sides are in equilibrium, the thermal output of the steam generators is calculated from the combination of feedwater flow,-tempering line flow, steam generator blowdown flow, and the associated.

enthalples for each flow. In addition, calculated reactor thermal power accounts for reactor coolant ~ pump heat addi-tion and primary side system losses. Thermal power is-Page 12 ,

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divided by the core rated BTU /hr at. full power'to compute '

%RTP:

egn. 1 RP = N [Osa - Op + {Qz / R)l100 g t where: RP -

% reactor thermal power. (RTP)

N -

number of primary side loops Qg.

3 steam generator thermal output (BTU /hr).

Op -

RCP heat adder (BTU /hr) ,

Qt primary system net heat loss (BTU /hr)

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Core rated BTU /hr at full power Steam generator thermal output is determined from feedwater flow, tempering line flow and blowdown flow. Feedwater flow is computed from equation 2 for each of the two taps on:the '

each loop's feedwater venturi.

k Wx,y " (a,,y)(Fay) DP"' r egn. 2 y

where: x- venturi tap number (1 or 2) y- loop number (1, 2, 3, or 4) 1 W- feedwater flow in Ibm /hr i a- venturi constant specific to the tap Fa-thermal expansion factor of the venturi DP- venturi differential pressure process parameter l v- feedwater specific volume which is a function of feedwater temperature and -l steam pressure  !

% H

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WESTING 800SE PROPRIETARY CLASS 3

, COMMONNEALTH EDISON COMPANY Tempering 1ine and' blowdown flows are determined by measur-ing the differential pressure across a flow orifice. The fe'ed flows are averaged and combined with tempering line flow to obtain the total feed flow. The process computer converts total feed flow and blowdown flow from GPM to Ibm /hr, and equation 3 is used to determine the loop steam generator power.

LPy = {FF, - BF y) h, + {BFy) h3 - {FFy ) h, '4**

where: LP -

loop steam generator power-(BTU /hr)-

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venturi tap number (1 or 2) y -

loop number (1, 2, 3, or 4) 4 FF -

total feedwater flow in Ibm /hr BF -

blowdown flow in lbm/hr h3 -

steam enthalpy calculated from steam pressure and' steam quality h-i saturated liquid enthalpy-  ;,_

h-y feedwater enthalpy from feedwater tem-perature and steam pressure The instrument uncertainties (Table 3) for the feedwater-flow, feedwater temperature, tempering line flow, blowdown flow and steam pressure measurements-are combined with each parameters sensitivity (Table 4) to determine the overall reactor power uncertainty. The four loop reactor power uncertainty is determined as follows:

otoop =

(arr +O FT +Ur - T +Or B +U SP )1! egn. 4-

= 2 (0.402 + 0.532+ 0.022 + 0.042 + 0.06 )1/2

= 0.67% RTP Page 14

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, Based on the number of-loops, the random error is 0.33% RTP '

and-the bias error is:

= EenFF - EenFT + EenTF - EenBF - Een3p Ie egn.-5

= 1 37 - 0.+ 0.05

. .0.06 - 0.20

= 1.16% RTP Assuming a normal, two sided probability distribution, the resulting daily power calorimetric uncertainty.at a 95%

confidence level is il.83% RTP. -

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.WESTINGEOUSE PROPRIETARY. CLASS 3 -l COMMONWEALTH EDISON' COMPANY

, TABLE 3 REACTOR POWER INSTRUMENT UNCERTAINTIES Process- Random Error (o) Bias ~ Error'(Een)

'Feedwater Flow i6.84 in.WC' 23.54 in.WC Feedwater Temperature 2.87*F 0 Tempering Line Flow il.92 gpm 4.95 gpm Blowdown Flow i3.37 gpm 5.14 gpm -

Steam Pressure f13.79 psi 50.05 psi TABLE 4 REACTOR POWER SENSI'TIVITIES Process Sensitivity' Interaction Feedwater Flow 0.058%/in.WC- direct Feedwater Temperature 0.185%/*F- reverse

. Tempering Line Flow 0.011%/gpm -direct Blowdown Flow 0.011%/gpm reverse. -

Steam Pressure 0.004%/ psi reverse l

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WESTINGEOUSE PROPRIETARY CLASS 3 COMMONWEALTH EDISON COMPANY

. 4. Reactor Coolant System Flow The uncertainties for Reactor Coolant System (RCS) Flow have not been explicitly determined at this time. Commonwealth -

Edison has assumed that the accuracy of this process parame-ter will'not' exceed i3.5% RCS flow for Byron and Braidwood.

The NRC has reviewed'and accepted a 3.5%'RCS flow uncertain-ty for Commonwealth Edison's Zion Station as discussed in CECO letter dated May 26, 1992 from S. F. Stimac to'Dr.

-Thomas E. Murley and subsequently approved in Zion license amendment #139/128 transmitted by C. P. Patel's letter.to'T.

J. Kovach dated June 26, 1992. Based on the Byron /Braidwood Technical Specification Requirement to perform feedwater venturi inspections each refueling outage, we have a high level of confidence that'the assumption'of 3.5% RCS flow-uncertainty is conservative.

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IV. CONCLUSIONS l

This evaluation of pressurizer pressure control', RCS temper- l ature control, NIS. power range and RCS flow uncertainties represents a reasonable methodology and a plant specific  ;

analysis of the Byron and Braidwood parameters effecting the RTDP design input. The Byron.and Braidwood uncerta'inty i values. used in the RTDP analysis are: equivalent to or'more-conservative than the values determined in the preceding sections.

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REFERENCES

1. Commonwealth Edison Company Technical Information Document TID-E/I&C-10, Revision 0, " Analysis of .n I stru-ment channel Setpoint Error and Instrument Loop Accura-cy"

2. Commonwealth Edison Company Technical Information Document TID-E/I&C-20, Revision 0, " Basis for Analysis of Instrument channel Setpoint Error and. Instrument Loop Accuracy" 1

3. Tuley, C.R., Miller, R.B., " Westinghouse Setpoint' Methodology for Control and Protection Systems", IEEE Transactions on Nuclear Science, February 1986, Vol.

NS-33 No. 1, pp. 684-687.

4. Westinghouse letter NS-EPR-2577, E.P. Rahe'to'C.H.

.Berlinger, NRC, dated March 31, 1982, " Westinghouse ,

partial response to the Improved Thermal' Design Proce- -

dure (Proprietary) "

5. NED-I-EIC-0004, Revision 1, " Byron /Braidwood Pressuriz-er-Pressure Channel Error Analysis" l

6. NED-I-EIC-0014, Revision 1, " Byron /Braidwood Tavg - AT Channel Error Analysis"

7. NED-I-EIC-0167, Revision 0, " Byron /Braidwood Turbine Impulse Pressure Switch and Indicator Error Analysis"

8. NED-I-EIC-0221,. Revision.0, " Byron /Braidwood Pressuriz- '

er Pressure Control System Instrument Loop Error Calcu-lation" Page 19  !

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9. NED-I-EIC-0223,-Revision 0, " Byron /Braidwood Rod Speed Control Uncertainty Calculation"

10. NED-I-EIC-0233, Revision -0, " Byron /Braidwood Daily.

Power Calorimetric, Accuracy Calculation"

11. NED-O-MSD-8, Revision 0, " Sensitivity Factors for'By-ron/Braidwood Power Calorimetric"

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12. ANSI /ISA Standard S67.04-1988, "Setpoints for Nuclear l Safety-Related Instrumentation" l

13. ANSI /ANS-58.4-1979, " Criteria for Technical Specifica-.

tions for Nuclear power Stations"

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! . 14. Westinghouse Revised Thermal Design Procedure Instru-ment Uncertainty Methodology for Commonwealth. Edison Zion Units 1 and 2 Nuclear Power Station,. August 1991, j WCAP 12801 (proprietary) and WCAP 12802 (non propri- I etary).

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ATTACHMENT 8 Commonwealth Edison Company I & C Engineering Letter March 1,1994 m

Electrical /I&C Engineering March 1,1994 In reply refer to CHRON#

, Tb: G.K. Schwanz 207699 Station Manager Byron Station K.L. Kofron Station Manager Braidwood Station

Subject:

Overtemperature Delta T Setpoint

Reference:

1) CAE-93-220, CCE-93-244, October 1,1993, " Byron and Braidwood Sta-tions, Steam Generator 'Ibbe Plugging and Thermal Design Flow Reduction Analysis Program, Revised OTAT/OPAT Trip Setpoints"

2) Byron 12tter 93-0579 (CHRON# 204964), October 21,1993, " Delta T Constants for Steam GeneratorIbbe Plugging Analysis" Review of reference 1 has indicated an additional constraint on the OTAT setpoint that was not initially evaluated as part of the Steam Generator Increased Tbbe Plugging program. The calculation performed by NETS I&C department for this setpoint incorporated changes to the channel gains, specifically changes to k1htAX and k3 from aference 1 and K1 NOM from reference 2. The selection of k1Nohi = 1.370 by Byron and Braidwood was sufficiently conservative, at that time, with respect to tlie analyzed channel accuracy.

We have determined that the change to the positive AI gain must also be considered. This will require additional total allowance in the OTAT setpoint. We have recommended and discussions with Penny Reister, Byron '1bch Staff, have concluded that it would be acceptable to revise the k1 Noht value to maintain the required positive margin.

L Recalculation of the OTAT setpoint accuracy results in the following required value:

k1Nohts;1.3250'

March 1,1994 Ihge 2 The change to the AI gain does not require any changes to the OPAT or low-Low gT g setpoints. If you have further questions, please call me at Downers Gmve extension 7263.

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I Pete VandeVisse I&C Engineer

'} /fNY-Pete Wicy/

I&C Supervisor cc: G.P. Wagner D.E. St. Clair R. A. Kerr P.E. Reister EW. Trikur T.L. O'Connor L.K. Kepley J.A. Bauer NEDCC h 'WOWintbidetta i WQf

ATTACHMENT 6 Operating Parameter Uncertainties for the Byron /Braidwood Revised Thermal Design Procedure Westinghouse Proprietary Class 2 I

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