jaf-calc-nbi-00205 setpoint calculation for vessel lo-lo ...calculation number: jaf-calc-nbi-00205...

CALCULATION SHEET Page No: 2 Total Pages: 30

Calculation Number: JAF-CALC-NBI-00205 Revision No: 0

REVISION SUMMARY SHEET

Revision No. Affected Pages Reason for Revision

0 All Initial issue

.



Table of Contents

1.0 Purpose .......................................................................................................................... 4

2.0 Inputs ............................................................................................................................. 6

3.0 Assumptions ..................................................................................................................11

4.0 References ....................................................................................................................11

5.0 Method of Analysis ........................................................................................................14

6.0 Numeric Analysis ...........................................................................................................15

7.0 Scaling ..........................................................................................................................27

8.0 Conclusions ...................................................................................................................29

9.0 Results ..........................................................................................................................30



1.0 Purpose

The purpose of this calculation is to determine the instrument channel uncertainties associated with the Reactor Water LO-LO Level 2 PCIS trip loop. This calculation establishes the Limiting Trip Setpoint (LTS) and an Allowable Value for this function.

Table 1

Instrumentation Table

1.1 Loop Function and Diagram

The transmitters 02-3LT-57A,B monitor reactor water level. The transmitters send a signal through Master Trip Units (MTU) to the bistable units 02-3STU-258A,B which actuate the primary relays 05A-K124A,B.

The Reactor Water Cleanup (RWCU) isolations occur when either 05A-K124A or 05A-K124B contacts actuate due to low water level in the reactor vessel. The purpose of this logic is to close 12MOV-15,12MOV-18, and 12MOV-69 which isolates RWCU. The Reactor Vessel Water Level 2 function associated with isolation is assumed in the analysis of the recirculation line break (LOCA).

Component ID Function Manuf/ Model No.

Rack/ Cabinet

Environmental Zone

2-3LT-57A,B Reactor Vessel Recirc Pump Trip and MSIV Closure Level Transmitter

Rosemount 1153DB5RC

Rack 25-05 300-3

2-3MTU-257A,B Reactor LO Level PCIS Master Trip Unit

Rosemount 510DU

(710DU)

Panel 09-91, 92 ATTS

2-3STU-258A,B Reactor LO Level PCIS Slave Trip Unit

Rosemount 510DU

(710DU)

Panel 09-91, 92 ATTS



Note: The A, B loops are identical.

Figure 1

Reactor Building Relay Room Elevation 284’ 8” Panel 09-91

02-3MTU-257A (Vessel Low Level 2 Logic A1) Not addressed with this calculation – see JAF-CALC-NBI-00202 MTE1

02-3STU-258A (Vessel Low Level 2 RWCU Isolation Logic)

MTE2

05A-K124A

02-3LT-57A

MTU Analog Output



2.0 Inputs

Table 2 Environmental Inputs

Zones

Location Event Humidity

Radiation (TID)

Temp (°F)

Ref.

300-3

Reactor Building 300 ft Elevation Column 3.5 Line - R Dose Pt. 3A

Normal

40-70% R.H. 1.8x104 R

(40 yrs)

65-100

4.1.26

Accident 100% R.H. 7.55x103 R (1 hour) (LOCA)

90 R

(HELB)

110 174

ATTS

Relay Room 284’8 ft Elevation Column 10 Line G

Normal 40-50% R.H. 1.75x102 R

(40 years)

60–90

4.1.7

4.4.2

4.4.3 Accident Same as

normal Same as normal

Same as normal

Table 3

MTE Table MAKE/MODEL RANGE OF

SCALE(S) ACCURACY FOR

SCALE USED TO

CALIBRATE

Comments

Fluke/8060A Or Equivalent

DMM

As Necessary

± (0.05%(RDG) + 2 digits)

(Resolution 0.001 VDC)

Transmitter 2-3LT-57A,B

(Ref. 4.2.1 and 4.2.2)

Mfg. Specs/PECO Energy Corp.

Manometer 0-2000 in. H2O (Ref.

4.1.19)

± 0.1% (RDG)

Transmitter 2-3LT-57A,B

(Ref. 4.2.1 and 4.2.2)

ISP-201A,B has a range of 0-16.8 In Hg

Digital

Readout Assembly

16 mA

± 0.17% of span

2-3MTU-257A,B 2-3STU-258A,B

4.2.3 4.2.4

4.1.24

Includes

standard used to calibrate MTE



Table 4

Design Inputs

Component ID Design Value Ref Comments

Reactor Vessel Water Level 2 trip

AL 454.94 inches above vessel zero

(102.44 inches TAF)

4.1.13

4.1.28

Determination of the Analytical Limit

2-3 LT-57A,B (Transmitter)

Input -230.89 to -81.81” H2O ΔP

149.08 In H2O ΔP Span

4.1.16 Corresponds to @ operating conditions; 14.5 to 224.5 “ H2O above TAF (210 In H2O Measured Span)

16.80 to 6.00 In Hg ΔP

4.2.1 4.2.2 4.2.3 4.2.4

Equivalent 0 psig calibration including correction for static pressure span shift: -229.10 to -81.18 In H2O ΔP

Output 4-20 mAdc (1-5 VDC) Nominal

4.3.3 4.3.4

4 vdc span over 210 In H2O span and 149.08” H2O ΔP

Span RA1 ± 0.25% 4.4.1

DDR1 ± 1.75% Span 4.1.21

Per 30 months

DR1 ±0.2% URL (30 months)

4.4.1 URL=750 In H2O (for Range 5)

RE1 ±4.0% URL 4.4.1 During and after exposure to 2.2 X 107 rads TID

SE1 ±0.5% URL 4.4.1

During and after a seismic disturbance defined by a required response spectrum with ZPA of 4g’s

SP1 ± 0.2% URL per 1000 psi (Zero) and ± 0.5% reading per 1000 psi

(Span)

4.4.1 Span effect correction uncertainty

PS1 < ±0.005% Span per Volt

4.4.1

TE1 ± (0.75% URL + 0.5% Span) per 100°F ΔT

4.4.1 URL = 750 In H2O (for Range 5)

ALT1 ± 0.01 Vdc (±0.25% Span)

4.2.1 4.2.2

Technician precision in setting the As Left device during calibration.

02-3MTU-257A,B 02-3STU-258A,B

Input 4-20 mAdc (16 mAdc span)

4.2.3 4.2.4

(4-20 mAdc) 14.5 to 224.5 In H2O

RA2A

± 0.15% span (MTU) 4.4.2

4.4.3 MTU Analog Output to Slave

ALT2A

± 0.1875% span 4.2.3 4.2.4

Calibration Tolerance

RA3T

(Trip )

± 0.20% span (STU) 4.4.2 4.4.3

Trip point repeatability requirements listed are valid for up to 6 months of operation.



This value is taken as Rated

Accuracy. ALT3T

± 0.2% span 4.1.1

Diff2

± 0.5 – 7.5% span 4.4.2

4.4.3 Reset Differential adjustment



3.0 Assumptions

3.1 In accordance with CC-JAF-IC-G-003 (Ref. 4.1.1), this function is a Type 2 setpoint and Rigor R2.

3.2 Temperature and radiation levels in the relay room, for the ATTS cabinets are negligible and considered a mild environment during normal and accident operating conditions. The Rosemount STU is located in the ATTS cabinets, a controlled environment area. Therefore, for the purposes of this calculation, the random error for normal and accident conditions are the same per Ref. 4.1.7, 4.4.2, and 4.4.3.

3.3 In order to maintain 105.4” H2O above TAF as the AV, the AL of 102.44” H2O above TAF has been verified for this function (Ref. 4.1.13, 4.1.28)

3.4 For M&TE devices, it is assumed that the standard used in calibration of the M&TE has an accuracy which is 4 times better than the accuracy of the calibrated M&TE as per the requirement stated in Section 4.6.2 of Test Equipment Calibration Program (Ref. 4.1.11).

3.5 Seismic uncertainty effects are not included in this calculation based on the following: Per Reference 4.1.10, this instrument loop’s functions are not required during and following a seismic event. They are, however, required to be operable before a seismic event. Should a seismic event occur, operability will be evaluated per Reference 4.1.12.

The effects of normal vibration (or a minor seismic event that does not cause an unusual event) on a component will be calibrated out on a periodic basis. As such, the uncertainty associated with this effect is negligible.

3.6 It is assumed that the effects of normal radiation are calibrated out on a periodic basis. Outside containment, there is not a substantial increase in radiation during normal operation. For this reason, the uncertainty introduced by radiation effects is assumed to be negligible.

3.7 Per Reference 4.4.1, the Rosemount 1153 transmitter specification has a Relative Humidity range of 0-100% R.H. There are no humidity-related errors in the vendors’ specification. Therefore, it is assumed that all other specifications are valid for 0-100% R.H. and HE1=0.

3.8 Per Reference 4.1.15 the energy release into the Reactor Building from a HELB event would be terminated prior to reactor vessel level decreasing to the level 3 trip. Therefore, IRE for environmentally harsh conditions resulting from an accident outside the drywell will not be considered.



3.9 Generally, the temperature at which an instrument is calibrated is

within the normal operating range of the instrument. Also, any ambient temperature effects are typically small. Therefore, the uncertainty associated with the temperature variations during calibration is assumed to be negligible. This assumption applies only to temperatures changes during calibration. Temperature effects over the expected range of equipment operation from the calibration temperature must still be considered.

3.10 This calculation has been completed for one LO-LO Level loop transmitter and STU (Loop 02-3LT-57A). Because the configuration of LO-LO level loops are identical, with the transmitters located on a similar rack, this configuration is applicable to loop 02-3LT-57B, per Ref. 4.3.3 and 4.3.4.

3.11 Rosemount Model Trip Units 510U and 710DU are interchangeable, and this calculation encompasses the use of either model. During accident conditions the two models have difference specifications and the worst case specification will be used to ensure interchangeability. However, for this calculation, the trip units are located in the relay room for which the normal condition exists during accident environment as per Section 2.0 Table 2.



4.0 References

4.1 JAFNPP Documents

4.1.1 CC-JAF-IC-G-003, Rev. 0 “Instrument Loop Accuracy and Setpoint Calibration Methodology"

4.1.2 CC-AA-309-1001, Rev. 10 “Guidelines for Preparation and Processing of Design Analyses”

4.1.3 JAF-CALC-05-00132, “Effect of the Revised Mass and Energy Released From RWCU Pipe Breaks on the Reactor Building Pressure and Temperatures” Rev. 0

4.1.4 JAFNPP, Final Safety Analysis Report

4.1.5 JAFNPP, Technical Specifications and Bases

4.1.6 JAFNPP Design Basis Document (DBD) -016, “Primary Containment Isolation System”, Revision 4.

4.1.7 JAFNPP Design Basis Document (DBD) -070, “Control Room Ventilation & Cooling Design Basis Document”, Revision 14.

4.1.8 JAFNPP, ITS and Bases

4.1.9 ROME PEDB, JAFNPP

4.1.10 USI-A-46, JAFNPP “Safe Shutdown Equipment and Relay Evaluation”, Rev. 5

4.1.11 Procedure PL-AA-001-0001, “Admin Process for the Performance of M&TE Calibration Activities at the Station.”

4.1.12 Procedure AOP-14, “Earthquake”, Rev. 19.

4.1.13 TODI-EC-625092-01, “JAF Reactor Water Cleanup Setpoint Change Design Inputs,” April 2019

4.1.14 JAF-RPT-PC-01283, Instrument Drift Analysis for PCIS, Rev. 0.

4.1.15 JAF-RPT-MULT-00206 Rev. 1, “Consideration of Temperature-Induced Uncertainties in Automatic Actuation Setpoints”.

4.1.16 EDE-21-0889, Supplement 1, Revision 0, August 1991, “Fitzpatrick Reactor Vessel Water Level Indication Evaluation (Power Uprate Condition)”

4.1.17 EDP-20, Rev 9, “Procedure for Establishing if Plant Equipment is within the scope of 10CFR50.49 (EQ).”

4.1.18 ETR 2062.1, Rev. 2, Ecotech Study for NYPA, “General Analysis of Cable Circuitry performance at JAFNPP,” issued 3-13-90, (EQ-371)



4.1.19 JAF I&C M&TE Calibration Program Master List, Dated 10-14-97.

4.1.20 IMP-71.26, Rev. 7 – ECCS and RPS Power Supply Functional Test (ATTS).

4.1.21 JAF-CALC-MULTI-03457 Rev.1, Drift020 Rosemount 1153DB5 Transmitters

4.1.22 EC 62731, Incorporation of Design Equivalent Modification D1-92-082, Rosemount Trip/Calibration Unit 510DU Replaced by 710DU

4.1.23 EC 5681/15660, Evaluation of Alternate M&TE

4.1.24 EC 44380, Inclusion of new Temperature Uncertainty Error

4.1.25 DRN-03-00587, Minor Calculation Change for Process Measurement Uncertainty

4.1.26 Specification 22A1290AC, Rev. 0, Reactor Building Ventilation

Cooling and Heating Systems

4.1.27 JAF-CALC-MISC-03364 Rev. 0, Rosemount Digital Readout Assembly – Test Equipment Total Uncertainty

4.1.28 GEH-005N2981, Rev. 0, JAFNPP Reactor Water Level Setpoint

Change for Reactor Water Cleanup System Isolation.

4.2 Instrument Surveillance Procedures

4.2.1 ISP-201A, Rev. 19

4.2.2 ISP-201B, Rev. 20

4.2.3 ISP-100A-PCIS, Rev. 17

4.2.4 ISP-100B-PCIS, Rev. 17

4.3 Drawings:

4.3.1 1.60-25 Rev. 14; Elem. Diag. Analog Trip SYS ATTS

4.3.2 FM-47A, Rev. 52; Flow Diagram Nuclear Boiler Vessel Instruments System 02-3.

4.3.3 LP-02-3E Rev. 3; Loop Diagram NBI Reac Recirc Pmp Trip Level and Pressure, MST Vlv Closure Level and ARI ATWS Pressure “A”.

4.3.4 LP-02-3F Rev. 3; Loop Diagram NBI Reac Recirc Pmp Trip Level

and Pressure, MST Vlv Closure Level and ARI ATWS Pressure “B”.



4.3.5 5.01-136 Rev. 4; “Reactor Assembly”.

4.4 Vendor Documents

4.4.1 Rosemount Model 1153 Series B Pressure Transmitters Manual: Publication No. 4302, Rev. 7, (R369-0030).

4.4.2 Rosemount Model 710 DU Trip/Calibration System Instruction Manual 4471, Rev. 2, (R369-0029).

4.4.3 Rosemount Model 510 DU Trip/Calibration System Instruction Manual 4247-1, Rev. 1, (R369-0032)



5.0 Method of Analysis

INSTRUMENT CHANNEL UNCERTAINTY (CU)

Per Reference 4.1.1, the instrument channel uncertainty can be calculated with a single loop equation containing all potential uncertainty values, or by a series of related term equations. The specific channel calculation will coincide with the channel's layout from process measurement to final output module or modules. Random channel uncertainties may be combined using Square Root Sum-of-Squares (SRSS) method. Any positive (B+) or negative (B-) bias associated with the instrument channel uncertainty is combined algebraically. The typical equation for linear CU will have the following form:

CU = ± 222

21

22 )(....)()( nRRR eeePEPM +++++ +B± + IRE

Where: PM = Random uncertainties that exist in the channel’s basic Process

Measurement.

PE = Random uncertainties that exist in the channels Primary Element or; any system element that quantitatively converts the measured variable energy into a form suitable for measurement.

B± =A sum total of all the bias components of the individual components and uncertainty of the process that consistently has the same algebraic sign and is expressed as an estimated limit of error.

IRE = Insulation Resistance Effect leakage allowance in % of span; resulting from high humidity and temperature subsequent to an accident.

e nR =Random uncertainties that are associated with any module or; assembly of interconnected components that constitutes an identifiable device, instrument, or piece of equipment.



6.0 Numeric Analysis

6.1 Process Measurement Effects

6.1.1 Reference Leg Temperature Effects

Reference 4.1.15 evaluates the PM for a small-break LOCA resulting in a PMBIAS = +1.7024 In H2O.

Therefore:

PMBIAS = +1.7024 In H2O

= +(1.7024 In H2O) / (210 In H2O)

= + 0.81% Span

There are no random errors identified in Reference 4.1.15.

Therefore:

PMRANDOM = 0

6.1.2 Primary Element Effect (PE)

There is no primary element in this configuration. Therefore:

PE=0

6.1.3 Insulation Resistance Error (IRE)

Per Section 3.8 accident uncertainties outside the drywell (HELB) do not have to be considered.

Therefore:

IRE = 0

6.2 Instrument Module Uncertainties

6.2.1 Transmitter (e1)

6.2.1.1 Reference Accuracy (RA1)

RA1 is included in the DDR1 term.



6.2.1.2 Determined Drift (DDR1)

Per Reference 4.1.21 the instrument drift evaluation provides a value for transmitter drift performance based on a statistical study of actual “as found” and “as-left” data. The maximum expected drift for a 30-month period for Rosemount transmitter is given as ±1.75% span.

Therefore:

DDR1 = ±1.75% span

6.2.1.3 Humidity Error (HE1)

Per Section 3.7, humidity error effects are not specified. Therefore:

HE1 = 0

6.2.1.4 Radiation Error (RE1)

Section 2.0, Input Table, RE1 = ± 4.0% URL accuracy during and after testing to 2.2x107. Per Section 3.6, radiation error is assumed to be negligible.

RE1 = 0

6.2.1.5 Seismic Error (SE1)

Per Section 3.5, there is no seismic error, therefore;

SE1 = 0

6.2.1.6 Static Pressure Error (SP1)

The static pressure error for the Rosemount 1153 consists of two components: Zero effect and Span effect.

Zero effect: SP1(zero)

Per Section 2, Table 4, the Rosemount 1153 transmitter zero effect error is ± 0.2% URL per 1000 psi. Using a nominal pressure of 1040 psi, then:

For Range 5; URL = 750 In H2O ΔP SP1(zero) = [(±0.2% ) *(750 In H2O ΔP) / 1000 psi]*1040psi = ± 1.56 In H2O ΔP SP1(zero) = (± 1.56 In H2O) / (149.08 In H2O ΔP) = ±1.05 % Span



Span effect: SP1(span)

Per Section 2 Table 4, the Rosemount 1153 transmitter span effect can be calibrated out, however the correction uncertainty is ± 0.5% of reading per 1000 psi. Using a nominal pressure of 1040 psi, and the maximum ΔP of 230.89 In H2O then: SP1(span) = [(±0.5% ) *(230.89” H2O ΔP) / 1000 psi]*1040psi = ± 1.201” H2O ΔP SP1(span) = (± 1.201” H2O) / (149.08” H2O ΔP) = ±0.8056 % Span

Using the Square Root Sum of Squares to combine the zero and Span effects:

SP1 = ± (1.05%2 + 0.81%2)½

SP1 = ± 1.326 % Span

6.2.1.7 Power Supply Error (PS1)

For this calculation, the power supply effect PS1 is included in the DDR1 term



6.2.1.8 Temperature Error (TE1)

Per Section 2.0, Table 4 the Rosemount temperature error is ±(0.75% URL + 0.5% Span) per 100°F ΔT. Per Section 3.8 accident uncertainties for an accident outside the drywell, (HELB) do not have to be considered since the energy release into the Reactor Building will be terminated prior to Reactor Vessel level reaching the level 3 setpoint. Per Ref. 4.1.15, Table 1 during LOCA conditions, the temperature in the Reactor Building is 110°F. From Section 2.0 the normal temperature is 65-100°F.

URL = 750” H2O ΔP (for Range 5)

TE1 = ±[(0.75%)*(750” H2O ΔP) +(0.5%)*(149.08 In H2O ΔP)]

*(110°F – 65°F )/(100°F)

= ±2.867 In H2O ΔP

TE1 = ± (2.867 In H2O ΔP)/(149.08 In H2O ΔP)

= 1.92% Span

6.2.1.9 Measuring &Test Equipment (MTE1)

MTE1 is included in the DDR1 term.

6.2.1.10 As-Left Tolerance (ALT1)

Per Section 2.0, As-Left Tolerance is ±0.01 Vdc. Then:

ALT1 = (± 0.01 Vdc) / (4 Vdc)

= ± 0.25% Span 6.2.1.11 Module Uncertainty

From Section 5, the general form of the device uncertainty equation is; e = ± (RA2 + DR2 + TE2 + RE2 + SE2 + HE2 +SP2 + MTE2 + ALT2 + PS2 )1/2 + B±

Substituting RA1, DR1, PS1 & MTE1 with the value of DDR1, and B± = 0 (Since no biases were identified), and removing the uncertainties listed as negligible or not applicable: e1 = ±( DDR12 + SP12 + TE12 + ALT12)1/2

e1 = ±[ (1.75%)2 + (1.326%)2 + (1.92%)2 + (0.25%)2]1/2

e1 = ± 2.93 % Span



6.2.2 Rosemount Master Trip Unit Analog Output (e2A)

The uncertainties determined here are applicable to the MTU analog output that feeds the STU bistable input.

6.2.2.1 Reference Accuracy – MTU Analog Output (RA2A)

The MTU RA for analog output (RA2A) to slave function is given in Section 2.0

RA2A = ± 0.15% Span

6.2.2.2 Drift (DR2A)

The trip point repeatability, Rated Accuracy, is valid for 6 months. Therefore, with a calibration frequency (SI) for the Trip Unit at 6 months, any drift value is included within the Rated accuracy.

Therefore: DR2A = 0

6.2.2.3 Temperature Error (TE2A)

Per Section 3.2, the temperature error associated with the MTU is included in the reference accuracy (Ref. 4.4.2 and 4.4.3) because the temperature profile is bounded (Ref. 4.1.7).

Therefore:

TE2A = 0

6.2.2.4 Humidity Error (HE2A)

There are no humidity-related errors described in the vendor’s specifications for this device. Per Section 3.2, humidity effects are considered negligible.

Therefore:

HE2A = 0

6.2.2.5 Radiation Error (RE2A)

Per Section 3.2, normal radiation induced errors are assumed to be small and capable of being adjusted out at each calibration. As such, normal radiation errors are considered negligible.

Therefore:

RE2A = 0



6.2.2.6 Seismic Error (SE2A)

Per Section 3.5, seismic effects are not applicable. Therefore:

SE2A = 0

6.2.2.7 Static Pressure Error (SP2A)

The MTU is an electrical device and as such is not affected by static pressure changes.

Therefore:

SP2A = 0

6.2.2.8 Power Supply Error (PS2A)

There are no power supply variation effects stated in the vendor’s specifications for this device. PS effect is considered to be negligible. (Ref. 4.4.2 and 4.4.3).

Therefore:

PS2A = 0

6.2.2.9 Measuring &Test Equipment (MTE2A)

The Rosemount Digital Readout (RDR) assembly will be used in calibrating the trip units. Per Section 2.0, Table 3 the readout assembly accuracy is specified as ± 0.17% of span.

Therefore:

MTE2A = ± 0.17% Span

6.2.2.10 As-Left Tolerance (ALT2A)

Per Section 2.0, As-Left Tolerance is ± 0.03 mAdc

ALT2A = (± 0.03 mAdc) / (16 mAdc)

= ± 0.1875 % Span



6.2.2.11 MTU Module Uncertainty

From Section 5.0, the general form of the device uncertainty equation is;

e = ±(RA2 + DR2 + TE2 + RE2 + SE2 + HE2 +SP2 + MTE2 + ALT2 + PS2)1/2 + B±

Removing the uncertainties listed as negligible or not applicable, the analog function will be: e2A= ± ( RA2A2 + MTE2A2 + ALT2A2)1/2

= ± (0.15%2 + 0.17%2 + 0.1875%2)1/2

= ± 0.29 % span

6.2.3 Rosemount Slave Trip Unit – Trip Function (e3T)

6.2.3.1 STU Trip Reference Accuracy (RA3T)

The STU Reference Accuracy for the trip function is given in Section 2 Table 4 as ± 0.2% of span.

Therefore:

RA3T = ± 0.2% span

6.2.3.2 Drift (DR3T)

The trip point repeatability, Reference Accuracy, is valid for 6 months. Therefore, with a calibration frequency (SI) for the Trip Unit at 6 months, any drift value is included within the Reference accuracy.

Therefore: DR3T = 0



6.2.3.3 Temperature Error (TE3T)

Per Section 3.2, the temperature error associated with the STU is included in the reference accuracy (Ref. 4.4.2 and 4.4.3) because the temperature profile is bounded (Ref. 4.1.7).

TE3T = 0

6.2.3.4 Humidity Error (HE3T)

There are no humidity-related errors described in the vendor’s specifications for this device. Per Section 3.2, humidity effects are considered negligible.

Therefore:

HE3T = 0

6.2.3.5 Radiation Error (RE3T)

Per Section 3.2, normal radiation induced errors are assumed to be small and capable of being adjusted out at each calibration. As such, normal radiation errors are considered negligible.

Therefore:

RE3T = 0

6.2.3.6 Seismic Error (SE3T) Per Section 1.2.5, seismic effects are not applicable for these devices. Therefore:

SE3T = 0

6.2.3.7 Static Pressure Error (SP3T)

The STU is an electrical device and as such is not affected by static pressure changes.

Therefore:

SP3T = 0

6.2.3.8 Power Supply Error (PS3T)

There are no power supply variation effects stated in the vendor's specifications for this device (Ref. 4.4.2). Therefore:

PS3T = 0



6.2.3.9 Measuring &Test Equipment (MTE3T)

The Rosemount Digital readout assembly is considered in MTE2A. Therefore:

MTE3T = 0

6.2.3.10 As-Left Tolerance (ALT3T)

Per Section 2.0, As-Left Tolerance is ± 0.2% span.

Therefore:

ALT3T = ± 0.2% span

6.2.3.11 STU Module Uncertainty

From Section 5.0, the general form of the device uncertainty equation is;

e = ± [RA2 + DR2 + TE2 + RE2 + SE2 + HE2 +SP2 + MTE2 + ALT2 + PS2 ]1/2 + B±

Removing the uncertainties listed as negligible or not applicable, and setting B± = 0 e3T = ± ( RA3T2 + ALT3T2)1/2

Substituting:

e3T = ± (0.2%2 + 0.2%2)1/2

= ±0.28% Span



6.3 TOTAL LOOP UNCERTAINTY (CU)

The general equation is found in Reference 4.1.1. This equation is reduced to the applicable terms for each module as developed below:

CU = ± [PM2 + PE2 + (e1 )2 + (e2) 2+ ....+ (e n)2]1/2 + B± + IRE

Where: PM = 0 No Primary Measurement error has been identified for this loop PE = 0 e1 = ± 2.93 % Span e2A = ± 0.29 % Span e3T = ± 0.28 % Span B = PMBias(Temp) = + 0.81 % Span IRE = 0

6.3.1 STU trip function (Transmitter, MTU & STU): Deleting the negligible and not applicable terms: CUSTU = ± (e12 + e2A2 e3T2)1/2 + PMBias(Temp) Substituting from above: e1 = ± 2.93 % Span e2A = ± 0.29 % Span e3T = ± 0.28 % Span PMBias(Temp) = + 0.81 % Span CUSTU = ± [(2.93%)2 + (0.29%)2+(0.28%) 2]1/2 + 0.81% = ± 2.96 % Span + 0.81 % Span

CUSTU+ = + 3.77 % Span

= 3.77% * 210 In H2O = 7.917 In H2O

CUSTU- = -2.15% Span

= -2.15% * 210 In H2O = -4.515 In H2O



6.4 Limiting Trip Setpoint

Per Reference 4.1.1, the Limiting Trip Setpoint for decreasing plant parameters is:

LTS = AL + CUSTU (No margin applied)

From Section 2, Data Input table, AL =102.44 In H2O above TAF

Substituting from above using the positive side of the CU for a decreasing parameter:

LTS = (102.44 In H2O) + (7.917 In H2O) LTS = 110.36 In H2O Decreasing This is the lowest value that the STU can be set to and not exceed the Analytical Limit.

6.5 Allowable Value(s)

Per Reference 4.1.1, for any setpoint that has an AL an Allowable Value (AV) shall be calculated for the total loop for that bistable and for each separate calibration test that is conducted on the associated instruments in that loop.

For decreasing plant parameters the AV is determined by: AV = LTS - AVTSMChannel

Where: AVTSMChannel = the statistical combination of the calibration error: Module AVTSM = ± [RA2 + MTE2 + ALT2 + DR2]1/2 AVTSMChannel = ± [AVTSM12 + AVTSM22 +… AVTSMn2]1/2

6.5.1 Transmitter AVTSM

The module 1 (transmitter) AVTSM is determined from comparison of Section 6.2 and applicable terms as follows:

AVTSMe1 = ± [RA2 + DR2 + MTE2 + ALT2]1/2

Per Reference 4.1.14 and 4.1.8, this is the components of DDR1 and ALT, Therefore substituting DDR1 and Alt values: AVTSMe1 = ± [DDR12 + ALT12]1/2



AVTSMe1 = ± [(1.75%)2 + (0.25%)2]1/2

AVTSMe1 = ± 1.77 % Span

6.5.2 MTU Analog Output AVTSM

The module 2 AVTSM is determined from comparison of Section 6.3 applicable terms as follows: AVTSMe2A = ± [RA2 + DR2 + MTE2 + ALT2]1/2 Substituting: AVTSMe2A = ± [(0.15%)2 + 0 + (0.17%)2 + (0.1875%)2]1/2 AVTSMe2A = ± 0.29% Span

6.5.3 STU trip function AVTSM

The module 2 AVTSM is determined from comparison of Section 6.3 applicable terms as follows: AVTSMe3T = ± [RA2 + DR2 + MTE2 + ALT2]1/2 Substituting: AVTSMe3T = ± [(0.2%)2 + 0 + (0)2 + (0.2%)2]1/2 AVTSMe3T = ± 0.28% Span

6.5.4 Channel AVTSM

The AVTSM can then be determined by combining the module values as follows: AVTSM = ± [AVTSMe12 + AVTSMe2A + AVTSMe2T2]1/2 = ± [(1.77%)2 + (0.29%)2 + (0.28%)2]1/2 AVTSM = ± 1.815 % Span

6.5.5 Calculated Allowable Value (CAV)

Recalling the CAV for a decreasing parameter is determined by:

CAV = LTS – AVTSM CAV = 110.36” H2O – 3.81” H2O = 106.6” H2O



7.0 SCALING

Scaling for the transmitter calibration is provided in JAF-CALC-NBI-00202 and thus will not be repeated here. The Master Trip Unit analog outputs are currently checked for calibration using the ATTS Calibration Unit as part of the indication checks and STU trip checks. If the MTU analog outputs require independent calibration, refer to the vendor manual or old I&C Department procedures that calibrated the master trip unit analog output functions.

7.1 STU (Trip Function) The input signal to STU is 4-20 mA, and the output is a trip. The new proposed field trip setpoint determined in Section 6.4 of this calculation is 110.36 In H2O (transmitter output). This value is converted to % span and milliamps, using the information from Section 2.0 as follows: 02-3STU-258A, B LTS in % Span = [(110.36-14.5) In H2O / 210 In H2O] * 100 = 45.6% LTS in mA = 4mA + 45.6% * 16mA = 11.3 mA 7.1.1 STU Trip As Found Zone (AFZ3T)

Per Ref. 4.1.1, for Safety-Related functions the AFZ can be determined by the following equation:

AFZ3T= ±AVTSMe3T

= ± 0.28 % Span

= ± 0.28% * 16mA = ± 0.0448 mA

7.1.2 As Left Tolerance (ALT3T) From Ref 4.1.1, the As-Left Tolerance is set equal to the RA of the device. From Table 4:

ALT3T = ± 0.2 % span = 0.2%*16mA = ±0.032 mA



7.2 STU Allowable Values

The Allowable Values for 02-3STU-258A,B will be scaled to support the testing units in mA: Allowable Valve calculated in Section 6.5 is 106.6 In H2O above Top of Active Fuel (TAF). This is converted to % span, milliamps, In H2O ΔP and using the information from Section 2.0 as follows: AV in % Span = [(106.6-14.5) In H2O / 210 In H2O] * 100 = 43.9% AV in mA = 4mA + 43.9% * 16mA = 11 mA



8.0 CONCLUSIONS

Line Diagram The figure below shows the relation of the limits, setpoints and the allowable values.

Note 1: Levels are with respect to Top of Active Fuel (TAF)

Note 2: Not to scale



9.0 RESULTS

Function CU LTS CAV AV AL

Reactor Vessel Water Level 2 trip

+7.917, -4.515 In H2O

110.36 In H2O

Decreasing

106.6 In H2O

Decreasing

≥105.4 In H2O

Decreasing

102.44 In H2O Above TAF

Scaling AFZ and ALT Results

Module AFZ ALT

Trip Trip 2-3STU-258A, B

± 0.045 mAdc

± 0.032 mAdc