NLS2024001, Application to Modify the Allowable Value for Cooper Nuclear Station Technical Specifications High Pressure Coolant Injection Pump Discharge Low Flow
| ML24047A273 | |
| Person / Time | |
|---|---|
| Site: | Cooper  |
| Issue date: | 02/16/2024 |
| From: | Dia K Nebraska Public Power District (NPPD) |
| To: | Office of Nuclear Reactor Regulation, Document Control Desk |
| References | |
| NLS2024001 | |
| Download: ML24047A273 (1) | |
Text
H Nebraska Public Power District NLS2024001 February 16, 2024 Attention: Document Control Desk U.S. Nuclear Regulatory Commission Washington, D.C. 20555-0001 "Always there when you need us" 50.90
Subject:
Application to Modify the Allowable Value for Cooper Nuclear Station Technical Specifications High Pressure Coolant Injection Pump Discharge Low Flow Cooper Nuclear Station, Docket No. 50-298, Renewed License No. DPR-46
Dear Sir or Madam:
Pursuant to 10 CFR 50.90, "Application for amendment of license, construction permit, or early site permit," Nebraska Public Power District (NPPD) is submitting a request for an amendment to Renewed Facility Operating License No. DPR-46 for Cooper Nuclear Station (CNS).
The proposed amendment revises the allowable value for CNS Technical Specifications (TS) 3.3.5.1, "ECCS Instrumentation," Table 3.3.5.1-1, "Emergency Core Cooling System Instrumentation," Function 3.f, "High Pressure Coolant Injection Pump Discharge Flow - Low (Bypass)," fromL 490 gallons per minute (gpm) toL 523 gpm. The proposed change to the TS is due to planned replacement of the flow-indicating switch with a different model. provides a description and assessment of the proposed change. Attachment 2 provides the existing TS pages marked up to show the proposed change. Attachment 3 provides revised ( clean) TS pages. The enclosure contains the setpoint calculation.
Approval of the proposed amendment is requested by February 15, 2025. Once approved, the amendment shall be implemented by April 30, 2025 to support the scheduled system work window.
NPPD has determined that there are no significant hazards considerations associated with the proposed change and that the TS change qualifies for a categorical exclusion from environmental review pursuant to the provisions of 10 CFR 51.22( c )(9).
The proposed TS change has been reviewed by the necessary safety review committees (Station Operations Review Committee and Safety Review and Audit Board). Amendments to the CNS Renewed Operating License through Amendment 274 issued on January 3, 2024, have been incorporated into this request. In accordance with 10 CFR 50.91, "Notice for public comment; State consultation," a copy of this application, with attachments, is being provided to the designated State of Nebraska Official. Copies to the Nuclear Regulatory Commission Region IV COOPER NUCLEAR STATION 72676 648A Ave/ P.O. Box 98 I Brownville, NE 68321 http://www.nppd.com
NLS2024001 Page 2 of2 office and the CNS Resident Inspectors are also being provided in accordance with 10 CFR 50.4(b )(1 ).
There are no regulatory commitments made in this submittal. If you should have any questions regarding this submittal, please contact Linda Dewhirst, Regulatory Affairs and Compliance Manager, at ( 402) 825-5416.
I declare under penalty of perjury that the foregoing is true and correct.
Executed On:
~ / 16/2. Y
' Date Siner Kh ta Site Vice President
/dv Attachments: 1. Description and Assessment Enclosure
- 2. Proposed Technical Specifications Change (Mark-up)
- 3. Revised Technical Specifications Page Calculation NEDC 92-050AA, Revision 6, "HPCI-FIS-78 (Switches 1 & 2)
Setpoint Calculation" cc:
Regional Administrator w/ attachments and enclosure USNRC - Region IV Cooper Project Manager w/ attachments and enclosure USNRC - NRR Plant Licensing Branch IV Senior Resident Inspector w/ attachments and enclosure USNRC-CNS Nebraska Health and Human Services w/ attachments and enclosure Department of Regulation and Licensure NPG Distribution w/ attachments and enclosure CNS Records w/ attachments and enclosure
NLS2024001 Page 1 of 10 Description and Assessment Cooper Nuclear Station, Docket No. 50-298, License No. DPR-46 1.0 Summary Description 2.0 Detailed Description 2.1 System Design and Operation 2.2 Current Technical Specifications Requirements 2.3 Reason for the Proposed Change 2.4 Description of the Proposed Change 3.0 Technical Evaluation 3.1 Proposed Equipment Change 3.2 Pressure Switch Configuration 3.3 Technical Analysis 3.3.1 Differences Between the Existing and Proposed Switch 3.3.2 Allowable Value Determination 4.0 Regulatory Analysis 4.1 Applicable Regulatory Requirements/Criteria 4.2 Precedent 4.3 No Significant Hazards Consideration Determination Analysis 4.4 Conclusion 5.0 Environmental Evaluation
NLS2024001 Page 2 of 10 1.0
SUMMARY
DESCRIPTION In accordance with 10 CFR 50.90, "Application for amendment oflicense, construction permit, or early site permit," Nebraska Public Power District (NPPD) is submitting a request for an amendment to Renewed Facility Operating License (OL) No. DPR-46 for Cooper Nuclear Station (CNS). The proposed change would amend the OL by revising the allowable value (AV) for CNS Technical Specifications (TS) 3.3.5.1, "ECCS Instrumentation," Table 3.3.5.1-1, "Emergency Core Cooling System [ECCS] Instrumentation," Function 3.f, "High Pressure Coolant Injection [HPCI] Pump Discharge Flow - Low (Bypass)," from ~ 490 gallons per minute (gpm) to~ 523 gpm.
2.0 DETAILED DESCRIPTION 2.1 System Design and Operation The safety design basis for HPCI is to provide protection to the core for the case of a small break in the reactor coolant pressure boundary which does not result in rapid depressurization of the reactor vessel. HPCI permits the nuclear plant to be shutdown while maintaining sufficient reactor vessel water inventory until the reactor vessel is depressurized. HPCI continues to operate until reactor vessel pressure is below the pressure at which Low Pressure Injection operation or Core Spray System operation can maintain core cooling.
The HPCI System consists of a steam driven turbine pump unit, piping, and valves to provide steam to the turbine, as well as piping and valves to transfer water from the suction source to the core via the feedwater system line. The system is designed to provide core cooling for a range of reactor pressures from 150 psid to 1120 psid. Upon receipt of an initiation signal, the HPCI turbine stop valve and control valve open simultaneously and the turbine accelerates to a specified speed. As HPCI flow increases, the turbine governor valve automatically adjusts to maintain design flow.
The HPCI pump is provided with a minimum flow bypass line, which discharges to the suppression pool. The minimum flow instrument actuates the minimum flow valve to protect the HPCI pump from overheating when the pump is operating at reduced flow. The minimum flow valve is opened when low flow is sensed and either 1) the pump is on, or 2) the system has initiated; and the valve is automatically closed when flow rate is adequate to protect the pump.
The minimum flow valve for HPCI is required to close to meet TS required injection flow but is not required to close to ensure that the ECCS flow assumed during the transients analyzed is met.
One flow switch, with two contacts, is used to detect the HPCI System's flow rate. The logic is arranged such that one flow switch contact causes the minimum flow valve to open (safety-related function). A second flow switch contact in the logic will close the minimum flow valve once the closure setpoint is exceeded (non-safety-related function). The AV is high enough to ensure that pump flow rate is sufficient to protect the pump, yet low enough to ensure that the closure of the minimum flow valve is initiated to allow full flow into the core.
NLS2024001 Page 3 of 10 2.2 Current Technical Specifications Requirements CNS TS 3.3.5.1, Table 3.3.5.1-1, Function 3.ffor the HPCI Pump Discharge Flow-Low (Bypass) requires an AV of ~ 490 gpm.
2.3 Reason for the Proposed Change The installed differential pressure indicating switch (DPIS) needs to be replaced due to obsolescence. Replacing the currently installed switch with a new model requires a change in the instrument setpoint as stated in the Technical Requirements Manual as well as the AV as stated in the Technical Specifications. The AV is being changed from~ 490 gpm to~ 523 gpm.
These changes are in the conservative direction as this is a decreasing setpoint.
2.4 Description of the Proposed Change The proposed change revises the AV for CNS TS 3.3.5.1, Table 3.3.5.1-1, Function 3.ffrom
~ 490 gpm to ~ 523 gpm. provides the existing CNS TS page marked to show the proposed change. provides the existing CNS TS page retyped to show the proposed change. There are no changes to the CNS TS Bases associated with the proposed amendment.
3.0 TECHNICAL EVALUATION
3.1 Proposed Equipment Change The installed DPIS is a Barton Model 289A and will be replaced with a Barton Model 58 lA.
The existing Barton 289A DPIS is Environmentally Qualified using Division of Operating Reactors Guidelines (per 10 CFR 50.49(k)), and the replacement Barton 581A DPIS will have an Environmental Qualification to IEEE 323-1974 (per 10 CFR 50.49(1)). A replacement, fully qualified 289A switch is not available. The Model 581A Barton switch specifications and configuration are very similar to the 289A and will perform the same function in the same manner as before. Both the installed and replacement flow indicating switch use a Model 199 differential pressure unit.
3.2 Pressure Switch Configuration The DPIS contains two switches, and each perform a function as described below:
Switch 1: This switch performs the safety-related function of opening the minimum flow bypass valve in the event oflow HPCI pump discharge flow. Upon reaching the setpoint, the low flow contact closes and energizes a relay that provides signals to open the minimum flow bypass valve and alarm in the control room. This switch setpoint is impacted by the proposed change.
Switch 2: This switch performs a non-safety-related function to close the minimum flow valve once HPCI pump discharge flow increases. Upon reaching the setpoint, the switch contacts close and actuate the minimum flow valve closing circuit. The setpoint for this switch is not impacted
NLS2024001 Page 4 of 10 by the change and will remain the same. As the setpoint for Switch 2 is not changing and is not safety-related, the changes to Switch 1 will be the focus of the technical analysis.
3.3 Technical Analysis 3.3.1 Differences Between the Existing and Proposed Switch Switch Repeatability: The replacement switch repeatability is used for vendor accuracy uncertainty. This uncertainty has increased by 0.5%, from 0.5% to 1.0%, with installation of the new switch. This change in accuracy impacted the calculation that determines the setpoint and TS AV.
Fluid Fill: The replacement switch uses distilled water rather than mineral/oil fill fluid type. Distilled water provides a higher radiation resistance to meet the ITT Barton (Cameron) Test Report 9A-CR3-580A-29 (Seismic) and Test Report 9A-CR3-580A-31 (EQ). These test reports need to be met to fully qualify the component to 10 CFR 50.49.
NOTE: There are other differences that do not affect the setpoint evaluation regarding the TS change that are not included. The installed and replacement switches each use the same differential pressure range and scale and have the same switch contact types. There is no change in how the switch performs its function. The existing process and wiring connections will be used for the new switch.
3.3.2 Allowable Value Determination CNS utilizes the Nuclear Regulatory Commission (NRC) approved General Electric (GE)
Instrument Setpoint Methodology as documented in GE Topical Report NEDC-31366P-A. The methodology is used to make reasonable predictions of instrument channel uncertainty and develop the setpoints and AV for a given instrument. The setpoint calculation has been revised for this change and found that the AV currently given in the TS would be less conservative than the new AV. The Analytical Limit is not being impacted by this change, only the AV and instrument setpoint are changed. Pertinent sections are provided below to demonstrate the impact of change on the setpoint calculation. Acronym definitions are provided on page 6.
NOTE: The following calculations are for explanatory purposes to demonstrate the impact of the change in switch repeatability on the calculated AV. For all equations, assumptions, references, and other calculated values, NEDC 92-050AA Revision 6, is provided (see Enclosure).
Determination of Device Accuracies:
VA=+/- Switch Repeatability*CS 289A: VA=+/- 0.5% x 14" H20 = +/- 0.070000" H20 581A: VA=+/- 1.0% x 14" H20 = +/- 0.140000" H20 The above VA is used to calculate various types of other accuracies, the calculations for the 581A switch will be shown from here on.
NLS2024001 Page 5 of 10 GE Setpoint Methodology is statistically based. The desired probability level used by the approved methodology is a 95% confidence. The 95% probability limit corresponds to approximately 2 standard deviations. The 'n' value is the number of standard deviations applied to a given value. Therefore, a value of 2 sigma equates to the required 95% confidence of the methodology.
Normal Accuracy {AN):
AN
= +/-2* [(V A/n)2 + (ATEN/n)2]
= +/-2* [(0.140000/2)2 + (0/2)2]
= +/-0.140000" H20 (2cr)
Trip Accuracy {AT):
AT
= +/-2* [(V A/n)2 + (ATET/n)2 + (SE/n)2 + (REi1n)2] + bias
= +/-2* [(0.140000/2)2 + (0/2)2 + (0.700000/2)2 + (1.400000/2)2]
= +/- 1.571496" H20 (2cr)
Individual calibration error terms are combined using SRSS method to determine the total calibration accuracy. The calibration accuracy is normalized to a 2 sigma confidence level as given the following equation:
Ci
= +/-2* [(ALT/n)2 + (CTOOL/n)2 + (CREAD/n)2 + (CSTD/n)2]
Ci
= +/-2* [(0.20/3)2 + (.052038/3)2 + (0.01/3)2 + (0.0/3)2]
= +/-0.137934" H20 (2cr)
Primary Element Accuracy:
A PEA is applicable for this type of instrument because a flow element is used to generate the differential pressure sensed by this instrument. The flow element used for this application is an orifice plate which is given an accuracy of+/- 2.02%. This accuracy is given in percent of flow, not percent of scale or nominal flow. Determining PEA at the low setpoint 4.25" H20:
+/-2.02% x 4.25" H20 = +/-0.085850" H20 (2cr)
Allowable Value Calculation:
Process variables which decrease to trip:
AV= AL+ (1.645/2)(SRSS of Random Terms)+ Bias Terms Therefore:
AV= AL+ ((1.645/2) [(ALT)2 +(CL(SW1))2 +(PMA)2 +(PEA)2+(IRA)2] +/- Bias Terms AV= 2.528750 + (1.645/2) [1.571496 2 + 0.1379342 + 0.02 + 0.0858502+ 0.02]
AV= 3.828195" H20
NLS2024001 Page 6 of 10 Converting AV to gpm:
AVcGPM)
= AVcctr)
- 267.261242
=3.828195
- 267.261242
= 522.917286 Rounded conservatively, the calculated AV is 523 gpm.
List of Acronyms Used:
AL= Analytical Limit ALT= As Left Tolerance ALT= Loop Accuracy in the Trip Condition (see note below, loop and individual accuracies are equal)
AN = Normal Accuracy AT = Trip Accuracy ATEN= Normal Condition Accuracy Temperature Effect ATET = Trip Condition Accuracy Temperature Effect AV = Allowable Value Ci = Calibration Accuracy CL= Loop Calibration Error CREAD = Calibration Tool Readability Error CS = Calibrated Span Csrn = Calibration Standard Error CrnoL = Calibration Tool Accuracy Error dP = Differential Pressure IRA = Instrument Resistance Accuracy Error PEA = Primary Element Accuracy PMA = Process Measurement Accuracy RE = Radiation Effect SE = Seismic Effect SRSS = Square Root of the Sum of the Squares SWl = Switch 1 VA = Vendor Accuracy Note that for given acronyms, an 'i' indicates an individual error term rather than a loop error term. Since the loop consists of a single device, loop errors are equal to individual device errors.
Results:
Low Flow (Switch 1)
Analytical Limit 425 gpm 2.528750" H20 Allowable Value 3.83" H20 523 gpm
NLS2024001 Page 7 of 10
==
Conclusion:==
The AV of 490 gpm as currently listed in the TS is less conservative than the new calculated AV of 523 gpm. Therefore, a change to the AV as listed in the TS is necessary.
4.0 REGULATORY ANALYSIS
4.1 Applicable Regulatory Requirements/Criteria CNS was not licensed to the 10 CFR 50, Appendix A, General Design Criteria (GDC). CNS was designed and constructed to meet the principle design criteria described in the Atomic Energy Commission's (AEC) proposed rule, "General Design Criteria for Nuclear Power Plant Construction Permits," published in the Federal Register on July 11, 1967 (32 FR 10213). The degree of conformance to the 1967 proposed GDC is described in Appendix F, "Conformance to AEC Proposed General Design Criteria" to the Updated Safety Analysis Report for CNS. The following NRC requirements were evaluated for their applicability to the proposed change.
1967 Proposed GDC Criterion 37 - Engineered Safety Features Basis for Design Engineered safety feature shall be provided in the facility to back up the safety provided by the core design, the reactor coolant pressure boundary, and their protection systems. As a minimum, such engineered safety features shall be designed to cope with any size reactor coolant pressure boundary break up to and including the circumferential rupture of any pipe in that boundary assuming unobstructed discharge from both ends.
1967 Proposed GDC Criterion 44 - Emergency Core Cooling Systems Capability At least two emergency core cooling systems, preferably of different design principles, each with a capability for accomplishing abundant emergency core cooling, shall be provided. Each emergency core cooling system and the core shall be designed to prevent fuel and clad damage that would interfere with the emergency core cooling function and to limit the clad metal-water reaction to negligible amounts for all sizes of breaks in the reactor coolant pressure boundary, including the double-ended rupture of the largest pipe. The performance of each emergency core cooling system shall be evaluated conservatively in each area of uncertainty. The systems shall not share active components and shall not share other features or components unless it can be demonstrated that (a) the capability of the shared feature or component to perform its required function can be readily ascertained during reactor operation, (b) failure of the shared feature or component does not initiate a loss-of-coolant accident, and ( c) capability of the shared feature or component to perform its required function is not impaired by the effects of a loss-of-coolant accident and is not lost during the entire period this function is required following the accident.
10 CFR 50.36, Technical Specifications, Criterion 3, requires that Technical Specifications limiting condition for operation be established for:
NLS2024001 Page 8 of 10 A structure, system, or component that is part of the primary success path and which functions or actuates to mitigate a design basis accident or transient that either assumes the failure of or presents a challenge to the integrity of a fission product barrier.
The proposed change ensures the automatic operation of the HPCI minimum flow valve occurs to protect the HPCI pump from overheating without adversely impacting the HPCI system availability or operation. Therefore, the proposed change is consistent with the requirements of the applicable GDCs and 10 CFR 50.36.
4.2 Precedent None 4.3 No Significant Hazards Consideration Determination Analysis Nebraska Public Power District (NPPD) is requesting to amend the Renewed Facility Operating License (OL) No. DPR-46 for Cooper Nuclear Station. The proposed change would amend the OL by revising the Technical Specifications, Section 3.3.5.1, Table 3.3.5.1-1, "Emergency Core Cooling System Instrumentation," Function 3.f, "High Pressure Coolant Injection Pump Discharge Flow - Low (Bypass)." The proposed amendment revises the allowable value from greater than or equal to 490 gallons per minute (gpm) to greater than or equal to 523 gpm. The proposed change is due to the planned replacement of the flow-indicating switch with a different model that has different operating characteristics.
NPPD has evaluated whether or not a significant hazards consideration is involved with the proposed amendment by focusing on the three standards set forth in 10 CFR 50.92, "Issuance of amendment," as discussed below:
- 1)
Does the proposed change involve a significant increase in the probability or consequences of an accident previously evaluated?
Response: No The proposed change to the High Pressure Coolant Injection (HPCI) Pump Discharge Flow - Low instrument allowable value allows the HPCI minimum flow bypass valve to function as originally designed to protect the pump from overheating during low flow conditions. The Analytical Limit remains unaffected. The HPCI system is used to mitigate the consequences of a small break loss of coolant accident (LOCA), and other accidents, abnormal operational transients, and special events when the main feedwater system is not available.
The probability of accidents previously evaluated is not affected, since the proposed change does not affect the way plant equipment is operated and thus does not contribute to the initiation of any of the previously evaluated accidents. The proposed change does not adversely affect accident initiators or precursors, and does not alter the design assumptions, conditions, or configuration of the plant or the manner in which the plant is operated or maintained.
NLS2024001 Page 9 of 10 The proposed change has no effect on the consequences of a postulated small break LOCA or other events where main feedwater system is not available, since the HPCI system will continue to perform its safety function as originally designed.
Therefore, the proposed change does not involve a significant increase in the probability or consequences of an accident previously evaluated.
- 2)
Does the proposed change create the possibility of a new or different kind of accident from any previously evaluated?
Response: No The proposed change to the allowable value permits the HPCI minimum flow bypass valve to function as originally designed. The proposed change does not alter the intent or purpose of the system flow instrumentation. The instrumentation will continue to function to operate the HPCI minimum flow bypass valve which protects the HPCI pump from overheating during low flow conditions.
Because the instrumentation will continue to function to protect the HPCI pump, the proposed change does not create the possibility of a new or different kind of accident from any previously evaluated. The proposed change does not introduce any changes or mechanisms that create the possibility of a new or different kind of accident.
Installed equipment is not being operated in a new or different manner. No new effects on existing equipment are created nor are any new malfunctions introduced.
Therefore, the proposed change does not create the possibility of a new or different kind of accident from any accident previously evaluated.
- 3)
Does the proposed change involve a significant reduction in a margin of safety?
Response: No The margin of safety provided by the flow instrumentation ensures the HPCI pump has adequate cooling during low flow conditions. The revised allowable value continues to provide assurance that flow is adequate for the HPCI pump during postulated small break LOCAs, and other accidents, abnormal operational transients, and special events when the main feedwater system may be not available.
The revised allowable value was determined based on a revised calculation using Nuclear Regulatory Commission-approved setpoint methodology. The Analytical Limit remains unaffected.
The proposed change does not adversely affect any current plant safety margins, or the reliability of equipment assumed in the safety analysis. There are no changes being made to any safety analysis assumptions, safety limits, or limiting safety systems that would adversely affect plant safety as a result of the proposed change.
NLS2024001 Page 10 of 10 Therefore, the proposed change does not involve a significant reduction in a margin of safety.
Based on the above, NPPD concludes that the proposed amendment does not involve a significant hazards consideration under the standards set forth in 10 CFR 50.92(c), and, accordingly, a finding of "no significant hazards consideration" is justified.
4.4 Conclusion In conclusion, based on the considerations discussed above, (1) there is reasonable assurance that the health and safety of the public will not be endangered by operation in the proposed manner, (2) such activities will be conducted in compliance with the Commission's regulations, and (3) the issuance of the amendment will not be inimical to the common defense and security or to the health and safety of the public.
5.0 ENVIRONMENTAL EVALUATION NPPD has determined that the proposed amendment would change a requirement with respect to installation or use of a facility component located within the restricted area, as defined in 10 CFR 20, or would change an inspection or surveillance requirement. However, the proposed amendment does not involve (i) a significant hazards consideration, (ii) a significant change in the types or significant increase in the amounts of any effluents that may be released offsite, or (iii) a significant increase in individual or cumulative occupational radiation exposure.
Accordingly, the proposed amendment meets the eligibility criterion for categorical exclusion set forth in 10 CFR 51.22( c )(9). Therefore, pursuant to 10 CFR 51.22(b ), no environmental impact statement or environmental assessment need be prepared in connection with the proposed amendment.
NLS2024001 Page 1 of2 Proposed Technical Specifications Change (Mark-up)
Cooper Nuclear Station, Docket No. 50-298, Renewed Operating License No. DPR-46 Revised Page 3.3-40
FUNCTION
- 3.
HPCI System (continued)
- f.
High Pressure Coolant Injection Pump Discharge Flow - Low (Bypass)
- 4.
Automatic Depressurization System (ADS) Trip System A
- a.
- Low Low Low (Level 1 )
- b.
Automatic Depressurization System Initiation Timer
- c.
- Low (Level 3)
(Confirmatory)
- d.
Core Spray Pump Discharge Pressure - High Table 3.3.5.1-1 (page 4 of 6)
Emergency Core Cooling System Instrumentation CONDITIONS REFERENCED FROM ECCS Instrumentation 3.3.5.1 APPLICABLE MODES OR OTHER SPECIFIED CONDITIONS REQUIRED CHANNELS PER FUNCTION REQUIRED SURVEILLANCE ALLOWABLE VALUE 2
2 ACTION A.1 REQUIREMENTS E
F G
F G
SR 3.3.5.1.2 SR 3.3.5.1.4(c)(d)
SR 3.3.5.1.5 SR 3.3.5.1.1 SR 3.3.5.1.2 SR 3.3.5.1.4(c)(d)
SR 3.3.5.1.5 SR 3.3.5.1.2 SR 3.3.5.1.4 SR 3.3.5.1.5 SR 3.3.5.1.1 SR 3.3.5.1.2 SR 3.3.5.1.4(c)(d)
SR 3.3.5.1.5 SR 3.3.5.1.2 SR 3.3.5.1.4 SR 3.3.5.1.5
~ 490-523 gpm
~ -113 inches s 109 seconds
~ 3 inches
~ 108 psig and s 160 psig continued (c) If the as-found channel setpoint is outside its predefined as-found tolerance, then the channel shall be evaluated to verify that it is functioning as required before returning the channel to service.
(d) The instrument channel setpoint shall be reset to a value that is within the as-left tolerance around the Limiting Trip Setpoint (L TSP) at the completion of the surveillance, otherwise, the channel shall be declared inoperable. Setpoints more conservative than the L TSP are acceptable provided that the as-found and as-left tolerances apply to the actual setpoint implemented in the Surveillance procedures (Nominal Trip Setpoint) to confirm channel performance. The Limiting Trip Setpoint and the methodologies used to determine the as-found and the as-left tolerances are specified in the Technical Requirements Manual.
(f) With reactor steam dome pressure >150 psig.
Cooper 3.3-40 Amendment No. 242
NLS2024001 Page 1 of2 Revised Technical Specifications Page Cooper Nuclear Station, Docket No. 50-298, Renewed Operating License No. DPR-46 Revised Page 3.3-40
FUNCTION
- 3.
HPCI System (continued)
- f.
High Pressure Coolant Injection Pump Discharge Flow - Low (Bypass)
- 4.
Automatic Depressurization System (ADS) Trip System A
- a.
- Low Low Low (Level 1)
- b.
Automatic Depressurization System Initiation Timer
- c.
- Low (Level 3)
(Confirmatory)
- d.
Core Spray Pump Discharge Pressure - High Table 3.3.5.1-1 (page 4 of 6)
Emergency Core Cooling System Instrumentation CONDITIONS REFERENCED FROM ECCS Instrumentation 3.3.5.1 APPLICABLE MODES OR OTHER SPECIFIED CONDITIONS REQUIRED CHANNELS PER FUNCTION REQUIRED SURVEILLANCE ALLOWABLE VALUE 2
2 ACTION A.1 REQUIREMENTS E
F G
F G
SR 3.3.5.1.2 SR 3.3.5.1.4(c)(d)
SR 3.3.5.1.5 SR 3.3.5.1.1 SR 3.3.5.1.2 SR 3.3.5.1.4(c)(d)
SR 3.3.5.1.5 SR 3.3.5.1.2 SR 3.3.5.1.4 SR 3.3.5.1.5 SR 3.3.5.1.1 SR 3.3.5.1.2 SR 3.3.5.1.4(c)(d)
SR 3.3.5.1.5 SR 3.3.5.1.2 SR 3.3.5.1.4 SR 3.3.5.1.5
- 2: 523 gpm
- 2: -113 inches
~ 109 seconds
- 2: 3 inches
- 2: 108 psig and
~ 160 psig continued (c) If the as-found channel setpoint is outside its predefined as-found tolerance, then the channel shall be evaluated to verify that it is functioning as required before returning the channel to service.
(d) The instrument channel setpoint shall be reset to a value that is within the as-left tolerance around the Limiting Trip Setpoint (L TSP) at the completion of the surveillance, otherwise, the channel shall be declared inoperable. Setpoints more conservative than the L TSP are acceptable provided that the as-found and as-left tolerances apply to the actual setpoint implemented in the Surveillance procedures (Nominal Trip Setpoint) to confirm channel performance. The Limiting Trip Setpoint and the methodologies used to determine the as-found and the as-left tolerances are specified in the Technical Requirements Manual.
(f) With reactor steam dome pressure >150 psig.
Cooper 3.3-40 Amendment No.
NLS2024001 Enclosure Page 1 of 1 Enclosure Calculation NEDC 92-0S0AA, Revision 6, "HPCI-FIS-78 (Switches 1 & 2) Setpoint Calculation" Cooper Nuclear Station, Docket No. 50-298, Renewed Operating License No. DPR-46
( Calculation contains 26 pages)
ATTACHMENT 9.2 Sheet 1 of 3 CALCULATION COVER PAGE NUCLEAR QUALITY RELATED 3-EN-DC-126 I
REV.3C6 MANAGEMENT MANUAL INFORMATION USE PAGE 28 OF 35 Engineering Calculation Process ENGINEERING CALCULATION COVER PAGE (19>RISK Significant 3
<5)CALCULATION NO: NEDC 92-0S0AA
,20) Effective Date:
,6) REVISION/Change Notice No: ___ 6 ___
- 2) Page 1 of 26 (1) EC#: DC 5438726 (7)Title: HPCI -FIS-78 (Switches 1 & 2) Setpoint Calculation (3) Design Basis Cale:
~ YES NO (11 ) Safety Class:
~ Quality Related D Non-Quality Related (18) Proprietary:
YES
~ NO (4) Superseded:
YES
~ NO (9) System(s)/Structure: HPCI I (10) Discipline: l&C (12)Component/Equipment/Structure:
HPCI-FIS-78 Switches 1 & 2 (21 ) Technical Conscience Review Board:
YES
~ NO (14) Keywords (Description/Topical Codes):
(8) Calculation
Description:
Calculation is to determine the required Allowable Value and instrument setpoint with associated analysis for the HPCI Pump Discharge Low Flow Indicating switch HPCI-FIS-78 (Switch 1 & 2).
HPCI-FIS-78 model 289A switch is being replaced with a model 581A switch (MM# 2120209). The setpoints are being recalculated for the new model. TSTF tolereances were also removed from Switch 2. This revision also incorporated CCN 5C1. This revision is being done as complete re-write so no revision bars are used.
(13) Conclusion/Recommendations:
The Low Flow Setpoint (Switch 1) is set at 5.00" H2O. The Allowable Value for the Low Flow Setpoint (Switch 1) required revision base on the results of this calculation.
The High Flow Setpoint (Switch 2) of 9.00" H2O is set according to Reference 2. Therefore, no change to the setpoint as listed in the Surveillance Procedures is necessary.
The Surveillance Procedure requires revision to incorporate the conclusions of this calculation.
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I fl.-1:l* Z.3
~ Design Verifier Supervisor/Approval D Technical Reviewer D Comments Attached D Comments Attached
<-------------~=-
'*********----------~
NUCLEAR QUALITY RELATED 3-EN-DC-126 I
REV. 3C6 MANAGEMENT MANUAL INFORMATION USE PAGE 31 OF 35 Engineering Calculation Process ATTACHMENT 9.3 CALCULATION REFERENCE 5HEET 5 Sheet 1 of 3 CALCULATION CALCULATION NO: NEDC 92-0S0AA REFERENCE SHEET REVISION/Change Notice: 6 I.a. Change Notices Incorporated List: 5C1 l.b. Change Notices NOT Incorporated List: None II. Relationships:
Sht Rev Input Pending Output Impact Tracking Doc Changes Doc Y/N No.
- 1.
Technical Amd.
LBDCR Specifications Table 242
[g]
~
y 2023-014 3.3.5.1-1, Function 3.f
- 2.
Surveillance 14
[g]
~
y IDOCS Procedure 6.HPCl.312 87949
- 3.
Surveillance 8
IDOCS 84206
~
y IDOCS Procedure 6.HPCI. 712 87950
- 4.
Alarm Procedure 39 IDOCS 84 733,
~
y IDOCS 2.3 9-3-2 87546,88398 87951
- 5.
DCD-2, High Pressure Coolant Injections
~
N N/A
{HPCI) System
- 6.
TRM Section 5.14
~
y LBDR 2023-014
- 7.
USAR VII - 4.0, VII -
2.0, Table Vll-2-1, VI-loep.xx
[g]
N 4.1.2 x5
- 8.
[g]
N
- 9.
VM 1734 3
[g]
N
- 10.
PBD-EQ 13
[g]
N
- 11.
B&R 2044 77
[g]
VER AF N
- 12.
EQDP.2.101 DOR 9
[g]
N
- 13.
EQDP.2.112 8
[g]
N
- 14.
JELCO X-2609-200 02
[g]
N
- 15.
NEDC 90-278 1
[g]
CCN 1C1 N
- 16.
DI 1064 1977
[g]
N
- 17.
DI 2544 01
[g]
N
- 18.
HGD 71-6 1 /6/71
[g]
N
- 19.
[g]
N SH. 12
- 20.
GE Letter C970115 1 /15/97
[g]
N
- 21.
NEDC 11-045 0
[g]
N
- 22.
NEDC 02-006 1
[g]
N
- 23.
NEDC 94-034D 3
[g]
N
- 24.
NEDC 97-023 3
[g]
N
- 25.
VM-1575 7
[g]
N
NUCLEAR QUALITY RELATED 3-EN-DC-126 I
REV. 3C6 MANAGEMENT MANUAL INFORMATION USE PAGE 31 OF 35 Engineering Calculation Process
- 26.
VM-0773 13 C3:J N
- 27.
VM-1733 3
[g]
N
- 28.
EE 23-005 C3:J N
Ill.
REFERENCES:
- 1. USAR, loep.xxx5 VII - 4.0, Emergency Core Cooling Control & Instrumentation, Section 4.2.4.5, HPCI Valve Control VII - 2.0, Reactor Protection System Instrumentation Environmental Conditions, Table Vll-2-1
- 2. J.E. Walker - P. D. Knecht, Analytical Limits for Cooper Nuclear Station, NEDC-32676P, General Electric Nuclear Energy, San Jose, CA, January 1997. Section 4.13
- 3. Not Used
- 4. Not Used
- 5. Crane Technical Paper No. 410, Crane Co., 300 Park Avenue, New York, NY 10022, Copyright 1991, Twenty-fifth Printing.
- 6. CNS Engineering Procedure 3.26.3, Rev. 9, Instrument Setpoint and Channel Error Calculation Methodology.
- 8. VM 1734 Rev. 3, Barton 199 Differential Pressure Units.
- 9. CNS Technical Specifications, Amendment 242, Table 3.3.5.1-1, Function 3.f
- 10. Not Used
- 11. SAP
- 12. PBD-EQ, Volume 2 of 2, Rev.13 "Environmental Qualification Program Basis Document, EQ Zones and Environmental Conditions"
- 14. Burns & Roe Drawing 2044, Rev. 77, Flow Diagram, High Pressure Coolant Injection and Reactor Feed Systems.
- 15. EQDP.2.101 DOR, Rev. 9, Equipment Qualification Data Package for Barton 288, 288A, 289A Differential Pressure Switches.
- 16. Not Used
- 17. Not Used
- 18. Not Used
- 19. Not Used
- 20. Not Used
NUCLEAR QUALITY RELATED 3-EN-DC-126 I
REV. 3C6 MANAGEMENT MANUAL INFORMATION USE PAGE 31 OF 35 Engineering Calculation Process
- 21. Not Used
- 22. G.E. Drawing 791 E271, Sh. 1, Rev. 57; Sh. 1A, Rev. 07; Sh. 2, Rev. 20; Sh. 3, Rev.
23; Sh. 4, Rev. 25; Sh. 4A, Rev. 05; Sh. 5, Rev. 25; Sh. 6, Rev. 22; Sh. 6A, Rev. 05; Sh. 7, Rev. 27; Sh. 8, Rev. 20; Sh. 9, Rev. 19; Sh. 10, Rev. 29; Sh.11, Rev. 01 Elementary Diagram High Pressure Coolant Injection System.
- 23. Jelco Drawing X-2609-200, Rev. N02, HP-2 HPCI to Reactor, Reactor Building, Class IIN.
- 24. NEDC 90-278, Rev. 1 C1, Accuracy of Selected Essential Flow Elements.
- 25. Not Used
- 26. Not Used
- 27. DI 1064, ITT Barton Product Bulletin 288A/289A-2 Indicating Switches, dated 1977.
- 28. HGD 71-6, GE Letter to Burns & Roe,
Subject:
Bore Calculations, dated January 6, 1971.
- 29. GE Instrument Data Sheet 234A9309NS, Sheet 12, Rev. 5.
- 30. Not Used
- 31. GE Letter, C970109-A, to CNS (Mark E. Unruh), CNS Setpoint Rounding Convention, dated January 9, 1997.
- 32. Not Used
- 33. Not Used
- 34. GE Letter C970115, from Yogi Dayal to Mark Unruh, dated 1/15/97, "Closure of Open Items Regarding Barksdale, SOR, Barton and Agastat Instruments."
- 35. Not Used
- 36. Not Used
- 37. Not Used
- 38. Not Used
- 40. CNS Operations Manual, Administrative Procedure 0.37, Rev.34, "Measuring And Test Equipment (M& TE) Calibration Program Guidelines".
- 41. VM 1733, Rev. 2, Cooper Nuclear Station Vendor Manual for Barton Model 289A and 291 A Differential Pressure Indicating Switches
- 42. NEDC 00-095A, Rev. 5, EQ Temperature, Relative Humidity, Pressure and Radiation
- 43. NEDC 02-006, Rev. 1, HELB EQ-RB Gothic Model
NUCLEAR QUALITY RELATED 3-EN-DC-126 I
REV. 3C6 MANAGEMENT MANUAL INFORMATION USE PAGE 31 OF 35 Engineering Calculation Process
- 44. NEDC 94-034D, Rev. 3, Small Steam Line Break Analysis
- 45. CR-CNS-2021-02033, Review NEDC 92-050AA to ensure there is at least a two sigma confidence level that the AFT will not exceed the Tech Spec limit.
- 46. EQDP.2.112 Rev 8, Barton Model 581A-0 Differential Pressure Indicating Switch
- 47. Vendor Manual 0773 Rev 13, Barton Differential Pressure Indicating Switches, Model 580A-0 & 581 A-0
- 48. DI 2544, ITT Barton Qualification Test Report No. R3-580A-29 for ITT Barton Models 580A, 581A, and 583A Mild Environment Differential Pressure Switch Instruments, dated 2/23/87
- 49. NEDC 11-045, Rev. 0, "Instrument Drift Analysis for Barton 289A and 581 A Differential Pressure (OP) Switches (Range 0 to 10 in WC)."
- 50. NEDC 03-27 Revision 4, "Assessment of Post LOCA Heat Up Temperature Profiles of Reactor Building"
- 51. NEDC 00-095D Rev1. "HELB EQ-RB Pressure Temperature Response"
- 52. NEDC 97-023 Revision 3 "HPCI Minimum Flow Line Evaluation"
- 53. DEC 5407264 "HPCI-FIS-78 Replacement" IV.
SOFTWARE USED:
Title:
Excel Version/Release: 365 MSI No. N/A
-'-~--
V.
DISK/CDS INCLUDED:
Description of Contents:....;..N..;.;../;;....;A ____________________ _
VI.
OTHER CHANGES: None
NUCLEAR QUALITY RELATED 3-EN-DC-126 I
REV. 3C6 MANAGEMENT MANUAL INFORMATION USE PAGE 34 OF 35 Engineering Calculation Process ATTACHMENT 9.4 RECORD OF REVISION Sheet 1 of 1 Revision 0
1 2
3 3C1 4
5 Record of Revision Initial issue. Determination of Setpoints for HPCI-FIS-78 (Switches 1 & 2), HPCI Flow Signals.
Determination of Allowable value and Setpoint for HPCI-FIS-78 (Switch 1 ),
HPCI' Flow Signals and determination of HPCI-FIS-78 (Switch 2) setpoint.
Incorporated CCN 1 C1, and changed status from 3 to 1. The text of CCN 1 C1 description is as follows:
As a result of the proposed increase in the Technical Specification allowable river temperature from 90°F to 95°F (License Amendment request NLS2002008), the overall tolerance of HPCI-FE-80 as calculated in NEDC 90-278 Revision 0C1 increased to 2.02%. This term is used to determine the Primary Element Accuracy (PEA) in section 4.1.5. Additionally, the High Pressure Coolant Injection System flow assumed in section 4.1.5 was reduced from 1000 GPM to 800 GPM to correspond to the minimum flow valve closure setting. A flow value of 800 GPM is still conservative because the flow element error is a percentage of flow at the point of interest and not a percentage of the span of the flow element (5000 GPM). As such, the Cross Reference index, the Setpoint Margin computation in section 4.1. 7.1, the Nominal Trip Setpoint (NTSP1) computation in section 4.1. 7.2 and the Allowable value (AV) computation in section 4.1.7.3 were affected.
Additional changes made during revisions are to update revisions to references, correct error in basis of Assumption 3.3, deleted pre-ITS information from conclusions section, updates calculation format to latest revision of EP 3.4.7.
Incorporated CCN 2C1, updated references Revises TSTF As-Found Tolerances from 3cr values to 2cr values.
Changed to Status 1. Incorporated CCN 3C1 and updated reference revisions as applicable.
Changed Low Setpoint to provide additional margin between AV and As-Found Tolerance.
6 NUCLEAR QUALITY RELATED 3-EN-DC-126 I
REV. 3C6 MANAGEMENT MANUAL INFORMATION USE PAGE 34 OF 35 Engineering Calculation Process Changed Low Setpoint and Allowable Value due to change in model of differential pressure switches from 289A to 581 A. Removed TSTF-493 tolerances from Switch 2.
- 1. PURPOSE NEDC 92-050AA Rev.6 Page 8 of 26 The purpose of this calculation is to determine the required Allowable Value and instrument setpoint with associated analysis for the HPCI Pump Discharge Low Flow Indicating switch HPCI-FIS-78 (Switch 1 & 2).
- 2. REQUIREMENTS 2.1 These switches provide HPCI Pump Discharge Flow signals to the HPCI minimum bypass valve HPCI-MO-25 and provide annunciation of HPCI discharge low flow conditions. The subject of this calculation is for the setpoint which opens the bypass valve on decreasing flow.
2.2 To prevent the turbine pump from being damaged by overheating at reduced HPCI pump discharge flow, a pump discharge minimum flow bypass is provided to route the water discharged from the pump back to the suppression pool. The bypass is controlled by an automatic, d-c motor-operated valve. At HPCI high flow, the valve is closed; at low flow, the valve is opened. A flow switch that measures the differential pressure across a flow element in the HPCI pump discharge pipeline provides the interlocks used for flow control.
There is also an interlock provided to close the minimum flow bypass whenever the turbine is tripped or isolation occurs. This prevents draining the emergency condensate storage tanks into the suppression pool. (Ref. 1, 14,
- 22) 2.3 The Analytical Limit for the HPCI Pump Discharge Low Flow Indicating switch HPCI-FIS-78 (Switch 1 ), is 425 gpm and there is no Analytical Limit for HPCI-FIS-78 (Switch 2) (Ref. 2).
Switch 2 setpoint will remain unchanged at 9" H2O (800 gpm) and is addressed in the Section 5 Conclusion. Since there is no requirement that the min flow valve close to support HPCI injection, no Analytical Limit is specified (Ref. 2, 52).
2.4 This calculation is performed in accordance with CNS Engineering Procedure 3.26.3 (Ref. 6), Instrument Setpoint and Channel Error Calculation Methodology.
2.5 This calculation is being performed using an Excel spreadsheet. Excel maintains mathematical precision to 16 decimal places and displays the calculated results at the precision defined for a particular cell. As such, differences between the results presented in this calculation and the results obtained by entering data into a handheld calculator may differ slightly. All calculated values are presented to 6 decimal places. Terms presented in Section 5.0 (Conclusions) are rounded according to the requirements of Reference 31.
- 3. ASSUMPTIONS 3.1 The flow element produces 0 - 350" H2O for a differential pressure equal to 0
- 5000 GPM (Ref. 11, 28). Since flow is proportional to the square root of the change of pressure, the following relationship may be used to convert from GPM to inches of H2O and vice versa (Ref. 5):
Q = cw NEDC 92-050AA Rev. 6 Page 9 of 26 where ~p is a value in inches of H2O, Q is the flow in GPM, and C is a constant of proportionality. For flow element HPCI-FE-80, C can be determined from the above information. Therefore:
C = (~) = (~~~~) = 267.261242 For example, to determine the inches of H2O for the analytical limit of 425 GPM, the following would be used:
(
425 GPM) 2
!:iP = 267.261
= 2.528750 inches H20 The instrument range for the flow indicating switch is O - 1000 GPM, which corresponds to O - 14" H2O. All error terms calculated shall remain in inches of H2O for consistency.
3.2 Not Used.
3.3 The safe working pressures for Barton Model 581A pressure switches that meets the specifications listed in Reference 4 7 is 3000 psig which is consistent with the design pressure of 1500 psig at 400°F at the orifice plate location (Ref. 23). Since these instruments are not subject to Over Pressure Effects (OPE). Therefore, OPE = 0 3.4 Reference 27 states that a "negligible static pressure shift" is an inherent feature of the Model 289A Differential Pressure Switch. Since the Model 289A and the Model 581 A both employ the Model 199 Differential Pressure Unit (DPU) (Ref. 27, 41, and 4 7), the "negligible static pressure shift" is also applicable to the Model 581A. On this basis the Static Pressure Effect (SPE) is assumed to be zero. Therefore, SPE = 0.
3.5 Seismic Effects are given by the vendor at +/-10.0% of Calibrated Span during and +/-5.0% following a seismic event (Ref. 4 7). This value of SE will be considered 2o (2 sigma). This only applies to trip conditions. The +/-5.0% of CS will be utilized this is when the trip condtion applies.
3.6 Not Used 3.7 NotUsed 3.8 The mechanical snap-action switches used in the Barton differential pressure indicating switch Model 581A are actuated by differential pressure acting against a diaphragm and spring tension. Therefore, Power Supply Effect (PSE) is assumed to be zero.
3.9 The Barton differential pressure indicating switch Model 581 A does not contained any components that are susceptible to radio frequency interference (RFI) or electro-magnetic interference (EMI). Therefore, RFI/EMI Effects (REE) are assumed to be zero.
3.10 The subject instrument is located in Rack 25-50 in EQ Zone 3 (SW Quad Room Elev. 859' 9", RHR B & D). Per Ref. 50, the Post LOCA peak temperature profile is bounded by; approximately 179°F at 3,600 seconds (1
NEDC 92-050AA Rev. 6 Page 10 of 26 hour3.009259e-4 days <br />0.00722 hours <br />4.298942e-5 weeks <br />9.893e-6 months <br />), 181 °Fat 6,000 seconds (1 hour1.157407e-5 days <br />2.777778e-4 hours <br />1.653439e-6 weeks <br />3.805e-7 months <br /> 40 minutes), 183°F at 28,800 seconds (8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br />), and 185°F at 75,000 seconds (approximately 20 hours2.314815e-4 days <br />0.00556 hours <br />3.306878e-5 weeks <br />7.61e-6 months <br />). However, the subject instrument is only assumed to function in Aux Steam and RCIC HELB scenarios. Per NEDC 00-095D (Ref. 51 ), neither of these scenarios results in an ambient temperature at the instrument location greater than 160°F. On this basis the maximum accident temperature is assumed to be 160°F.
RR suction line break - HPCI is not required since the vessel depressurizes so rapidly Small Steam Line Break (SSLB) inside Containment we analyzed the accident without HPCI (see NEDC 94-034D (Ref. 44), Attachment C)
SAFER/GESTR does not assume HPCI operation for the Feedwater or Main Steam Line Breaks outside containment.
HPCI Steam Line break - instrument is not required since the steam supply is isolated.
RWCU line breaks outside the Drywell - HPCI is not required because vessel level does not fall to Level 3 RHR HELB for the SW Quad is a branch of the HPCI Steam Supply line and it also isolates the steam supply to HPCI.
3.11 Not Used 3.12 All vendor accuracies are 2a values, unless otherwise noted. (Ref. 6).
3.13 Not Used 3.14 Not Used 3.15 This equipment is required to operate for 8 hours9.259259e-5 days <br />0.00222 hours <br />1.322751e-5 weeks <br />3.044e-6 months <br /> into the accident.
3.16 Calibration Temperature Range of 65 to 104°F is assumed based on Item 6 of Reference 13.
3.17 It is assumed that the M& TE instrument used in performance of the Surveillance Procedures (Ref. 7) is a Crystal Model IS33-36/3000 psi and as required by the Surveillance Procedures, the LP port is utilized. On this basis the values for CTOOL, CREAD and CSTD are based on a 0-36 psi range specifications from Reference 39.
3.18 It is assumed that the Crystal Model IS33-36/3000 psi is calibrated using a standard with a "tolerance no > 1/4 the tolerance of the M& TE" in accordance with para 6.2 of Reference 40. As stated in para 4.3.1.2.b.2 of Reference 6; "If Ci is greater than or equal to 4 times Cism, then Cisrn can be considered negligible." Therefore, CisTD = 0.
3.19 Not Used 3.20 Degradation of insulation resistance (IRE) is only a concern in the communication between analog instruments (e.g., between a transmitter and an indicator). Since these instruments are snap action switches (Ref. 47) IRE is not a concern. Therefore, IRE= 0.
3.21 Rev. 2 of this calculation referenced EQDP-46 as the source document for the normal and accident environment for the subject instruments. Since Revision 2
NEDC 92-050AA Rev. 6 Page 11 of 26 was issued, EQDP 46 has been superseded by PBD-EQ (Ref. 12) which lists the normal maximum temperature as 120°F, but does not provide a normal minimum temperature.
To establish a minimum temperature, the actual temperature plant temperatures as sensed by TE 105C and recorded on PMIS point N380 were examined. The examination revealed that the minimum and maximum temperature recorded over the 15 year sample period to be 58.08°F and 112.29°F respectively. On this basis the normal minimum and maximum temperatures are assumed to be 58°F (examination of historical data) and 120°F (Ref. 2, 12).
3.22 Barton states for Model 581A, a combined effect of a Design Basis Event (accuracy, temperature, pressure, relative humidity, and radiation) is a +/-10%
error. For the purpose of this calculation, RE will be +/-10% of calibrated range for trip condition and will include accuracy temperature effects for the trip conditions (ATEr). The Model 581 A differential pressure switchs employ a Model 199 Differential Pressure Units (DPU) wich are temperature compensated over a range of service conditions from -60°F to +200°F (Ref.
48). Since the temperature compensation range encompasses the normal calibration range of temperatures, A TEN and DTE are zero.
3.23 Due to Barton 289A and 581A Differential Pressure switches being similarly constructed, it is assumed that drift would be similar. NEDC 11-045 (Ref. 49) analyzes both these types of DP switches. The ranges are similar to the switches analyzed in NEDC 11-045. Therefore, the analyzed drift from this calculation will be used.
- 4. METHODOLOGY 4.1. Instrument Channel Accuracy 4.1.1. Channel Diagram (Ref. 1, 14, 22)
\\...
flovv input from HPCI-FIS-78 HPCI-FE-80 4.1.2. Definition of Channels This is a single instrument channel.
Closure of HPCI-M0-25 I
on High Flmv of HPCI-~vf0-25 onLmvFlmv 4.1.3. Instrument Definitions and Determination of Device Error Terms 4.1.3.1. Instrument Definition Reference CIC:
HPCI-FIS-78 (Sw. 1 & 2) 11
Location:
Manufacturer:
Model:
Full Span (FS)
Calibrated Span (CS):
Input Signal:
Existing Setpoint:
Output Signal:
Vendor Performance Specifications:
R-859-SW Quad IR 25-50 ITT Barton 581A 14" H20 0-1000 GPM 0 -14" H20 Switch 1 = 4.25" H20 Switch 2 = 9.00" H20 Contact Closure See Section 4.1.3.3 4.1.3.2. Process and Physical Interfaces Calibration Conditions Calibration Temperature Range Calibration Interval Normal Plant Conditions:
Temperature:
24 mo.+ 25%
Radiation:
2.1 x 104 R TID/40 yr Pressure:
-0.1 to -1.0" H20 Humidity:
20 - 90% R.H.
Trip Environmental Conditions:
Temperature:
58 - 160°F Radiation:
7.63x105 R Pressure:
-0.1 to -1.0" H20 Humidity:
100% R.H.
Long Term Post Accident Conditions:
NEDC 92-050AA Rev.6 Page 12 of 26 7
47 47 47 29 29,53 7
7 14,22 Reference Assum. 3.16 9
Assum. 21 12 42 1
1 Assum. 3.10, Assum. 3.21 Assum. 3.15, 12 12 12 Assumption 3.15 Seismic Conditions:
During Function:
Assumption 3.5 Temperature Range for Trip Condition Error Calculations:
Total Temp Range (l\\ Tr) = larger of
{
max trip temp - min calib temp 160°F - 65°F = 95°F max calib temp - min trip temp 104°F - 58°F = 46°F Temp Range for DTE calc (fl To)
= max calib temp - min calib temp
= 104°F - 65°F = 39°F
Temp Range for ATE calc (LiTAr)
= Li Tr - Li To NEDC 92-050AA Rev. 6 Page 13 of 26
= 95°F - 39°F = 56°F Temperature Range for Normal Condition Error Calculations:
Total Temp Range (Li TN) = larger of
{
max normal temp - min calib temp 120°F - 65°F = 55°F max calib temp - min normal temp 104°F - 58°F = 46°F Temp Range for ATE calc {LiTAN) = 6TN -LlTo
= 55°F - 39°F = 16°F 4.1.3.3. Determination of Device Accuracies 4.1.3.3.1. Vendor Accuracy (VA)
Value Sigma Reference VA
= +/- 1.0% of Calibrated Span Calibrated = 14" H2O Span VA
= +/- 1.0%
- 14" H2O VA
= +/- 0.140000" H2O 4.1.3.3.2. Accuracy Temperature Effect (ATE)
Value Sigma Per Section 4.1.3.2 the range of normal and accident temperatures is bounded by the temperature compensation (Assumption 3.22).
Therefore:
ATEN= ATEr = 0 2
4.1.3.3.3. Other Errors Normal Conditions:
Value OPE = 0 SPE
= 0 SE
= 0 RE
= 0 HE
= 0 PSE
= 0 REE = 0 2cr 47 4.1.3.1 Reference Assum. 3.22 Sigma Reference Assum. 3.3 Assum. 3.4 Assum. 3.5 Assum.
3.22 Assum.
3.22 Assum. 3.8 Assum. 3.9
TriQ Conditions:
= +/- 5.0% cs
= +/- 5.0%
- 14" H2O
= +/- 0. 700000" H2O RE
= +/- 10% cs
+/- 10%
- 14" H2O
+/- 1. 400000" H2O HE
= 0 PSE
= 0 REE
= 0 Long Term Post Accident Conditions:
= N/A RE
= N/A HE
= N/A PSE
= N/A REE
= N/A 4.1.3.3.4. Accuracy Values NEDC 92-050AA Rev. 6 Page 14 of 26 Sigma Reference Assum. 3.3 Assum. 3.4 2
Assum. 3.5 2
Assum. 3.22 Assum. 3.22 Assum. 3.8 Assum. 3.9 Sigma Reference Assum. 3.15 Assum. 3.15 Assum. 3.15 Assum. 3.15 Assum. 3.15 Assum. 3.15 Assum. 3.15 The identified accuracy error contributions are combined using the SRSS method to determine total device accuracy.
Device accuracy is normalized to a 2 sigma confidence level as given the following equation from Reference 6:
Ai*= +/-2*[(VAi/n) 2 + (ATEi/n)2 + (OPE/n)2 + (SPEi/n)2 +
(SEi/n)2 + (REi/n)2 + (HEi/n)2 + (PSEi/n)2 + (REEi/n)2] + any other terms Where "n" is the sigma value associated with each individual effect.
Normal Accuracy (AN):
Substituting:
AN = +/-2*[(VA/n)2 + (ATEN/n)2]
= +/-2*[(0.140000/2) 2 + (0/2)2]
= +/-0.140000" H2O (2a)
Trip Accuracy (Ar):
NEDC 92-050AA Rev. 6 Page 15 of 26 Ar = +/-2*[(VAi/n) 2 + (ATEr/n)2 + (SEi/n)2 + (REi/n)2]
+ bias
= +/-2*[(0.140000/2)2 + (0/2)2 + (0. 700000/2)2 +
( 1.400000/2 )2]
= +/- 1.571496" H2O (2cr)
Long Term Post Accident Conditions (Ap):
AP= N/A 4.1.3.4. Determination of Individual Device Drift 4.1.3.4.1. Statistical Determined Drift (Os)
Per Assumption 3.23: The bounding Analyzed Drift (DA) for Barton 581A DP Switches (Range Oto 14 in WC) has been determined to be+/- 9. 766% Setpoint (random) for 30 months (24 months + 25% ), with no significant bias. The Analyzed Drift should be treated as a normally distributed, 2a value for uncertainty analysis.
Ds = +/- 9.766% of Setpoint (2cr)
(Ref. 49)
Assuming Setpoint is the existing setpoint per Reference 7:
Ds(sw1)
= +/- 9. 766% x 4.25" H2O (Ref. 7)
= +/- 0.415055" H2O (2cr)
Ds(sw2)
= +/- 9.766% x 9.0" H2O
= +/- 0.878940" H2O 4.1.3.4.2. Drift Temperature Effect (DTE)
Value Sigma 4.1.3.4.3. Drift Values Per Section 4.1.3.2 the range of calibration temperatures is bounded by the temperature compensation (Assumption 3.22). Therefore:
DTE= 0 2
(Ref. 7)
(2cr)
Reference Assum. 3.22 The device drift error is determined by combining the drift terms using the SRSS method and normalized to a 2 sigma confidence value as given the following equation from Reference 6:
Di
= +/-2*[(VDi/n)2 + (DTEi/n)2] + any bias terms
NEDC 92-050AA Rev. 6 Page 16 of 26 Where Un" is the sigma value associated with each individual effect.
Substituting:
Di(SW1) = +/-2*[(0s/n)2 + (DTE/n)2] - bias
= +/-2*[(0.415055/2) 2 + (0/2)2]
= +/-0.415055" H2O (2a)
Di(sw2) = +/-2*[(Ds/n) 2 + (DTE/n)2] - bias
= +/-2*[(0.878940/2) 2 + (0/2)2]
= +/-0.878940" H2O (2a) 4.1.3.5. Establishing As-Left Tolerances The Calibration Tolerance for this instrument is established in CNS Surveillance Procedures 6.HPCl.312 REV.7 as the setpoint +/-0.20" H2O for Switch 1 (low flow setpoint) and setpoint +/-0.50" H2O for Switch 2 (high flow setpoint).
Al Ti(SW1)
ALTi(SW2)
= +/-0.20" H2O
= +/-0.50" H2O (3a)
(3a)
The TSTF-AL T as established in Section 4.2.1 is less restrictive than the As-Left Tolerance in the Calibration Procedures.
The TSTF-AL Twill only be used for Switch 1. Therefore, the TSTF-AL T value will be used in this calculation:
Therefore: AL T(sw1)= +/-0.20" H2O (3a) 4.1.3.6. Determination of Device Calibration Error 4.1.3.6.1. Device Calibration Tool Error According to Reference 7, these instruments are calibrated using a Crystal Model 33 digital pressure indicator, LP port and a Simpson VOM to monitor the switch contact position.
Since the Calibration Tool Errors are controlled by procedure they are assumed to have a 3 sigma confidence level in accordance with Reference 6.
Value Sigma Reference Input M& TE - Crystal Model 33 Digital Pressure 7
Indicator, LP port Accuracy Switch 1 (Low Flow Setpoint)
CroOL
= +/- (0.05% of Rd +
39 0.005% of FS)
NEDC 92-050AA Rev. 6 Page 17 of 26 Where:
(3cr)
ROG
= Existing Setpoint
= 4.25" H2O 7
FS = 36 psi 39 Conversion = 0.036063 psi Factor 1" H2O 39 FS = 36 psi/0.036063psi/1" H20 FS = 998.253057" H20 CrooL
= +/- ((0.05%*4.25) +
(0.005% *998.253057)"
H20
= +/- 0.052038" H20 Value Sigma Reference Accuracy Switch 2 (High Flow Setpoint)
CrooL
= +/- (0.05% of Rd +
39 0.005% of FS)
Where:
ROG
= Existing Setpoint
= 9.00" H2O 7
FS
= 36 psi 39 Conversion = 0.036063 psi Factor 1" H2O 39 FS
= 36 (3cr) psi/0.036063psi/1" FS
= H2O 998.253057" H2O CrooL
= +/- ((0.05%*9.00) +
(0.005%*998.2530 57)" H2O
= +/- 0.054413" H20 Readability CREAD
= 0.01" H2O (3cr) 39 Standard Csrn
= 0 (3cr)
Assum. 3.18 Output M&TE - None Required Accuracy (output CrooL
= 0 Readability CREAD
= 0 Standard Csro
= 0
4.1.3.6.2. Device Calibration Error NEDC 92-050AA Rev. 6 Page 18 of 26 Individual calibration error terms are combined using SRSS method to determine the total calibration accuracy. The calibration accuracy is normalized to a 2sigma confidence level as given the following equation from Reference 6:
Ci = +/-2*[(AL Ti/n)2 + (CTOOL/n)2 + (CREADi/n)2 +
(CSTDi/n)2]
Substituting the values from 4.1.3.5 and 4.1.3.6.1:
Switch 1 (Low Flow Setpoint)
Ci(SW1) = +/-2*[(0.20/3)2 + (.052038/3)2 + (0.01/3)2 +
(0.0/3)2]
= +/-0.137934" H2O (2cr)
Switch 2 (High Flow Setpoint)
Ci(SW2) = +/-2*[(0.50/3) 2 + (0.054413/3)2 + (0.01/3)2 +
(0.0/3)2]
= +/-0.335368" H2O (2cr) 4.1.4. Determination of Loop / Channel Values Since this loop consists of a single device, loop errors are equal to the individual device errors.
4.1.4.1. Loop Accuracy Values Normal Accuracy (ALN):
ALN = AiN
= +/-0.140000" H2O Trip Accuracy (ALT):
ALr= Air
= +/-1.571496" H2O Post Accident Conditions (ALP):
ALP= AiP
= N/A 4.1.4.2. Loop Drift Value DL = Di DL(SW1)= +/-0.415055" H2O DL(SW2)= +/-0.878940" H2O (2a)
(2a)
(2a)
(2a)
4.1.4.3. Loop Calibration Value CL= Ci CL(SW1) = +/-0. 13 7934" H2O CL(SW2) = +/-0.335368" H2O 4.1.5. Determination of PEA and PMA (2o)
(2o)
NEDC 92-050AA Rev. 6 Page 19 of 26 Primary Element Accuracy (PEA): A PEA is applicable for this type of instrument because a flow element is used to generate the differential pressure sensed by this instrument. The flow element used for this application is an orifice plate which is given an accuracy of+/- 2.02% (Ref.
24). This accuracy is given in percent of flow, not percent of scale or nominal flow. Determining PEA at the low and high flow setpoints 4.25" H2O and 9" H2O respectively (Ref. 2):
+/-2.02% x 4.25" H2O = +/-0.085850" H2O
+/-2.02% x 9.00 11 H2O = +/-0.181800" H2O (2cr)
(2cr)
Process Measurement Accuracy (PMA): PMA is not applicable since any head changes in a sensing line due to density changes would be equal on both sides of the differential pressure instrument.
4.1.6. Determination of Other Error Terms All error terms to be considered have been accounted for in the previous sections.
4.1.7. Calculation of Setpoint Margin and Operating Setpoint The stated purpose of this calculation is to determine the Allowable Value and Setpoint associated with the HPCI Pump Discharge Low Flow Indicating switch HPCI-FIS-78 (Switch 1 ). Therefore, Switch 2 values are not calculated.
4.1.7.1. Setpoint Margin (SM) Calculation Setpoint margin (SM) is defined as the difference between the Nominal Trip Setpoint (NTSP) and the Analytical Limit (AL). As given in Reference 6; SM= (1.645/2)(SRSS of Random Terms)+ Bias Terms Where:
"(1.645/2)" establishes SM as 2 sigma and adjusts the results to a single sided 95% probability.
"Random Terms" include the random portions of ALr, CL, DL, PMA, PEA, IRA, and any other unique terms known to exist.
NEDC 92-050AA Rev. 6 Page 20 of 26 "Bias Terms" includes the bias portion of ALT, CL, DL, PMA, PEA, IRA, and any other unique terms known to exist.
Therefore:
SM = +/-(1.645/2)[(ALT)2 +(CL(SW1))2 +(DL(SW1))2
+(PMA)2+(PEA)2 +(I RA)2]+Bias Terms Substituting:
SM = +/- (1.645/2) [1.571496 2+0.137934 2+0.415055 2+0.0 2
+0.0858502+0.02]
= +/-1.343540" H2O (2cr) 4.1.7.2. Nominal Trip Setpoint (NTSP1) Calculation The process variable decreases towards trip for HPCI-FIS-78 (Sw. 1 ). From Reference 6, for;
- process variables which increase to trip, NTSP1 = Limiting Setpoint - SM
- process variables which decrease to trip, NTSP1 = Limiting Setpoint + SM For this calculation the Analytical Limit (AL) is taken from Reference 2:
AL = 425 GPM
= 2.528750" H2O (Ref. 2)
(Assumption 3.1)
Therefore, the Nominal Trip Setpoints are:
NTSP1
=AL+ SM
= 2.528750" H2O + 1.343998" H2O
= 3.872290" H2O (2cr) 4.1. 7.3. Allowable Value (AV) Calculation From Reference 6, for;
- process variables which increase to trip, AV= AL - (1.645/2)(SRSS of Random Terms)+ Bias Terms
- process variables which decrease to trip, AV= AL+ (1.645/2)(SRSS of Random Terms)+ Bias Terms Where:
- "(1.645/2)" establishes SM as 2 sigma and adjusts the results to a single sided 95% probability.
- "Random Terms" include the random portions of ALT, CL, PMA, PEA, IRA, and any other unique terms known to exist.
- "Bias Terms" includes the bias portion of ALT, CL, PMA, PEA, IRA, and any other unique terms known to exist.
NEDC 92-050AA Rev. 6 Page 21 of 26 Therefore, the Allowable Values setpoints are:
AV= AL+/- (1.645/2) [(ALT)2 +(CL(SW1))2 +(PMA)2 +(PEA)2+(IRA)2]
+/- Bias Terms Substituting:
AV = 2.528750+ ( 1.645/2) [1.571496 2 + 0.1379342 + 0.02 +
0.0858502+ 0.02]
= 3.828195" H20 (2cr)
Converting AV to GPM per Assumption 3.1:
- 267.261242
= 3.828195
- 267.261242
= 522.917286 GPM Since the AV calculated above is more conservative than the Technical Specifications, calculated AV will be used from here on. Therefore; AV= 523 GPM
= 3.83" H20 4.1.7.4. LER Avoidance From Reference 6, an LER Avoidance Evaluation is performed to ensure that there is sufficient margin provided between the AV and NTSP to avoid violations of the Tech Spec Allowable value which could lead to LER conditions. The LER Avoidance Evaluation is performed using only those errors that are expected to be present during surveillance testing.
4.1.7.4.1. Random Terms Included In LER Avoidance From Reference 6; Sigma(LER) = (1/2) (SRSS of Random Terms)
Where "Random Terms" include the random portions of ALN, CL and DL.
Therefore:
Sigma(LER) = (1/2) [ALN 2 + CL(sw1)2 + DL(sw1)2]
Substituting:
Sigma(LER) = (1/2) [0.140000 2 + 0.1379342 +
0.4150552]
= 0.229617" H20 4.1. 7.4.2. LER Margin Calculation From Reference 6; Z(LER) = I AV - NTSP1 I/ Sigma(LER)
Substituting:
Z(LER) = I 3.83 - 2.872290 I / 0.230607
= 0.184176
4.1. 7.4.3. Governing Setpoint Determination NEDC 92-0S0AA Rev. 6 Page 22 of 26 Per Reference 6, for a single instrument channel, Z should be 1.29 or greater to satisfy the LER Avoidance criteria.
Comparing the results from above with the LER Avoidance Criteria from Reference 6 shows:
Z(LER)
= 0.184176 < 1.29 This means that the LER (Tech Spec Action)
Avoidance criterion is not met with setpoint at NTSP1, and there is a need to calculate NSTP2.
Per Reference 6, if Z is not greater than or equal to 1.29, an adjusted value of NTSP should be calculated using the following:
process variables which increase to trip, NTSP2 = AV - (Desired Margin)(Sigma (LER))
process variables which decrease to trip, NTSP2 = AV + (Desired Margin)(Sigma (LER))
The more conservative of NTSP1 and NTSP2 is the governing value.
Using 1.29 as the "Desired Margin" and substituting values from above:
NTSP2
= 3.83 + (1.29)(0.22961 T' H2O)
= 4.126206" H2O Therefore, NTSP is set to equal the setpoint that meets the LER Avoidance Criterion:
NTSP = NTSP2 = 4.126206" H2O
= 4.13" H2O (Rounded up to CREAD) 4.1. 7.5. Selection of Operating Setpoints This section is only for the operating setpoints of Switch 2.
Switch 1 operating setpoints will be calculated in Section 4.2.
The setpoint for Switch 2 is set 9.00" +/- LAT. The LAT is established for Switch 2 in Section 4.1.7.6.
4.1.7.6. Establishing Leave Alone Zones This section is only for the operating setpoints of Switch 2.
Switch 1 operating setpoints will be calculated in Section 4.2 Since the loop has only has one device, the loop Leave Alone Tolerance is the the device Leave Alone Tolerance. Only Switch 2 is calculated since Switch 1 is calculated in Section 4.2.
3 LAT= +- VA 2 + D 2
-2 LAT = +/-(3/2)[0.1400000 2 + 0.8789402]
+/- 1.335030" H2O N EDC 92-050AA Rev. 6 Page 23 of 26
+/- 1.33" H2O (Rounded down to CREAD) 4.1.7.7. Required Limits Evaluation Per procedure 3.26.3 (Ref. 6), since this a single instrument loop, the required limits evaluation is not required.
4.1.7.8. Spurious Trip Avoidance Evaluation See Section 4.2.4 of this calculation for Spurious Trip Avoidance Evaluation.
4.1.7.9. Elevation Correction The instrument is located on Rack 25-50 at elevation 863.42' (Ref. 11 ). The low side and high side taps for this instrument are located at elevation 870'-10" (Ref. 23) and are routed such that the effects due to elevation correction are not applicable
( elevation correction is not applicable to differential pressure if it taps at the same elevation).
4.1.7.10. Determination of Actual Setpoint From Reference 6, the Actual Setpoint is the Operating Setpoint (NTSP from Section 4.1. 7.4) plus or minus the Elevation Correction. Only Switch 1 setpoint is calculated.
Therefore; ASP
= NTSP + Elevation Correction
= 4.13" H2O + 0.0" H2O
=4.13"H2O 4.2.
Determination of TSTF-493 Values Implementation of TSTF-493 involves calculation of new As-Left Tolerance (ALT}, As-Found Tolerance (AFT) and performance of a Required Limits Evaluation. If NTSP3 does not meet the TSTF Required Limits acceptance criteria, then the setpoint is adjusted to satisfy the acceptance criteria. Only Switch 1 values are calculated.
NOTE: Only those terms that are uniquely defined within TSTF-493 are in this section. Except for those terms calculated below, values for all terms used below were taken from Section 4.1 of this calculation.
4.2.1. TSTF As-Left Tolerance NEDC 92-050AA Rev. 6 Page 24 of 26 This calculation will determine the TSTF As-Found and TSTF As-Left Tolerances for the low flow switch (Sw. 1 ).
In accordance with Attachment 2 of Reference 6, TSTF device As-Left Tolerance (ALT) is:
AL Ti = +/- 2 x SQRT[ {VA / n) 2 + (Crnoun/n)2 + (Csmn /n)? + (CREADin /n)?]
Substituting:
AL Ti(Sw. 1) = +/- 2 [ (0.140000/2) 2 + (0.052038/3) 2 +
(0.0/3)2+ (0.01 /3)2 ]
= +/- 0.144388" H2O
= +/- 0.14" H2O (2cr)
(Rounded down to CREAo)
Comparing Calibration Tolerance from the Surveillance Procedure 6.HPCl.312 Rev 7 to AL Tr From Section 4.1.3.5, Cal Tolerance (SW1) = 0.2" H2O (3cr)
= (2/3) X 0.2" H2O
= 0.133333" H2O (2cr)
Since the 2cr value for Calibration Tolerance is less than (i.e., more conservative) AL Ti as calculated above ALTL
= AL Ti AL TL(sw1) = +/- 0.20" H2O (Rounded down to CREAD) (3cr) 4.2.2. TSTF As-Found Tolerance In accordance with Attachment 2 of Reference 6, TSTF As-Found Tolerance (AFT) is:
AFTi = +/- 2*[(DL /n) 2+ ( AL TL /n) 2] +/- DRIFT BIAS TERMS Substituting:
AFTi(sw1) = +/- 2*[(DL(sw1) /n) 2+ ( ALTL(sw1J /n) 2] +/- DRIFT BIAS TERMS
= +/- 2* [ (0.415055/2) 2 + (0.20/3) 2]
= +/- 0.435945" H2O (2cr)
AFTL(sw1) = +/- 0.43" H2O (rounded down to CREAD) (2a)
Since application of AFTi(sw1) at the calculated setpoint for Switch 1 would violate the AV (4.13" H2O - 0.43" H2O = 3.70" H2O < 3.83" H2O) AFTL(SW1) must be restricted. Therefore:
AFTL(SW1)
= + 0.43, -0.42" H2O (2cr)
As the lower limit of the AS-found is restricted a larger margin from the AV is desired. Therefore, a setpoint of 5.00" H2O with a tolerance of +/-.43" H2O (2a) will provide the desired margin. This
NEDC 92-0S0AA Rev. 6 Page 25 of 26 admin setpoint is acceptable since the min flow valve opening prior to the TSTF calculated value will not harm the pump or HPCI system operation.
4.2.3. TSTF Required Limits Evaluation Since this is a single instrument loop, the required Limits Evaluation is not required.
4.2.4. TSTF Spurious Trip Avoidance The Spurious Trip Avoidance Evaluation ensures that there is sufficient margin between the selected NTSP and normal operating conditions. The function of the min flow setpoint is to open the min flow valve to prevent pump damage due to insufficient cooling. If the min flow valve opens prematurely it will not harm the pump or HPCI system operation. Therefore, a Spurious Trip Avoidance Evaluation is not required.
NEDC 92-050AA Rev. 6 Page 26 of 26
- 5. CONCLUSIONS The setpoints and calibration data for instrument HPCI-FIS-78 (Sw. 1 & 2) are as follows:
Low Flow (Switch 1)
High Flow (Switch 2)
Analytical Limit 425 GPM N/A 2.528750" H2O NIA Allowable Value 3.83" H2O N/A 523 GPM N/A Operating Setpoint 4.13" H2O N/A Elevation Correction 0.0" H2O N/A Actual Field Setpoint 4.13" H2O (deer)
Ref. 2
( calculated)
Actual Field Setpoint (Ref. 7) 4.25" H2O ( deer) 9.00" H2O (incr)
Admin Setpoint 5.00" H2O (deer)
+/-0.20" H2O N/A Tolerance) (3o)
ALT (As-Left Tolerance)
N/A
+/-0.50" H2O (30)
TSTF AFT (As-Found
+/-0.431' H2O N/A Tolerance) (2o)
AFT (As-Found Tolerance)
N/A
+/-1.33" H2O (2o)
The Allowable Value of GPM as currently listed in the Technical Specifications (Ref. 9) is less conservative than the calculated Allowable Value. Therefore, a change to the Allowable Value as listed in the Technical Specifications is necessary.
The Low Flow Admin setpoint (Switch 1) of 5.00" H2O is more conservative than the calculated setpoint of 4.13" H2O. A change to the setpoint as listed in the Surveillance Procedure is necessary to provide the Admin limit based on CR-CNS-2021-02033 ( Ref. 45)
The High Flow Setpoint (Switch 2) of 9.00" H2O is set according to Reference 2.
Therefore, no change to the setpoint as listed in the Surveillance Procedures is necessary.
The Surveillance Procedure requires revision to incorporate the new Allowable Value, Admin Setpoint, TSTF As-Found and As-Left tolerances listed above.