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LLC Submittal of Nuclear Steam Supply System Advanced Sensors Technical Report, TR-0316-22048, Revision 1
	ML18274A392
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Site:	NuScale
Issue date:	10/01/2018
From:	Bergman T; NuScale
To:	; Document Control Desk, Office of New Reactors
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LO-0718-61021 October 1, 2018 Docket No.52-048 U.S. Nuclear Regulatory Commission ATTN: Document Control Desk One White Flint North 11555 Rockville Pike Rockville, MD 20852-2738

SUBJECT:

NuScale Power, LLC Submittal of "Nuclear Steam Supply System Advanced Sensors Technical Report," TR-0316-22048, Revision 1 NuScale Power, LLC (NuScale) hereby submits Revision 1 of the "Nuclear Steam Supply System Advanced Sensors Technical Report" (TR-0316-22048). The purpose of this submittal is to request that the NRC review and approve the methodology presented in this report contains the proprietary version of the report entitled "Nuclear Steam Supply System Advanced Sensors Technical Report." NuScale requests that the proprietary version be withheld from public disclosure in accordance with the requirements of 10 CFR § 2.390. The enclosed affidavit (Enclosure 3) supports this request. Enclosure 1 has also been deemed to contain Export Controlled Information. This information must be protected from disclosure per the requirements of 10 CFR § 10. contains the nonproprietary version of the report entitled "Nuclear Steam Supply System Advanced Sensors Technical Report."

This letter makes no regulatory commitments and no revisions to any existing regulatory commitments.

If you have any questions, please contact Paul lnfanger at 541-452-7315 or at pinfanger@nuscalepower.com.

Sincerely, Distribution: Robert Taylor, NRC, OWFN-7H4A Samuel Lee, NRC, OWFN-8G9A Prosanta Chowdhury, OWFN-8G9A Bruce Bavol, NRC, OWFN-8G9A : "Nuclear Steam Supply System Advanced Sensors Technical Report", TR-0316-22048-P, Revision 1, proprietary version : "Nuclear Steam Supply System Advanced Sensors Technical Report", TR-0316-22048-NP, Revision 1, nonproprietary version : Affidavit of Thomas A. Bergman, AF-0718-61023 NuScale Power, LLC 1100 NE Circle Blvd , Suite 200 Corvallis, Oregon 97330 Office 541.360-0500 Fax 541.207.3928 www.nuscalepower.com

LO-0718-61021 :

Nuclear Steam Supply System Advanced Sensors Technical Report, TR-0316-22048-P, Revision 1, proprietary version NuScale Power, LLC 1100 NE Circle Blvd., Suite 200 Corvallis, Oregon 97330 Office 541.360-0500 Fax 541.207.3928 www.nuscalepower.com

LO-0718-61021 :

Nuclear Steam Supply System Advanced Sensors Technical Report, TR-0316-22048-P, Revision 1, nonproprietary version NuScale Power, LLC 1100 NE Circle Blvd., Suite 200 Corvallis, Oregon 97330 Office 541.360-0500 Fax 541.207.3928 www.nuscalepower.com

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 Licensing Technical Report Nuclear Steam Supply System Advanced Sensor Technical Report September 2018 Revision 1 Docket: 52-048 NuScale Power, LLC 1100 NE Circle Blvd., Suite 200 Corvallis, Oregon 97330 www.nuscalepower.com

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 Licensing Technical Report COPYRIGHT NOTICE This report has been prepared by NuScale Power, LLC and bears a NuScale Power, LLC, copyright notice. No right to disclose, use, or copy any of the information in this report, other than by the U.S.

Nuclear Regulatory Commission (NRC), is authorized without the express, written permission of NuScale Power, LLC.

The NRC is permitted to make the number of copies of the information contained in this report that is necessary for its internal use in connection with generic and plant-specific reviews and approvals, as well as the issuance, denial, amendment, transfer, renewal, modification, suspension, revocation, or violation of a license, permit, order, or regulation subject to the requirements of 10 CFR 2.390 regarding restrictions on public disclosure to the extent such information has been identified as proprietary by NuScale Power, LLC, copyright protection notwithstanding. Regarding nonproprietary versions of these reports, the NRC is permitted to make the number of copies necessary for public viewing in appropriate docket files in public document rooms in Washington, DC, and elsewhere as may be required by NRC regulations. Copies made by the NRC must include this copyright notice and contain the proprietary marking if the original was identified as proprietary.

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 Licensing Technical Report Department of Energy Acknowledgement and Disclaimer This material is based upon work supported by the Department of Energy under Award Number DE-NE0000633.

This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference herein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed herein do not necessarily state or reflect those of the United States Government or any agency thereof.

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 Licensing Technical Report CONTENTS Abstract ....................................................................................................................................... 1 Executive Summary .................................................................................................................... 2 1.0 Introduction ..................................................................................................................... 5 1.1 Purpose ................................................................................................................. 5 1.2 Scope .................................................................................................................... 5 1.3 Abbreviations ......................................................................................................... 6 2.0 Background ..................................................................................................................... 8 2.1 Technology ............................................................................................................ 9 2.2 Spares ................................................................................................................... 9 2.3 Assumptions and Design Guidance .................................................................... 10 2.4 Alternative Sensor Options .................................................................................. 10 2.5 Regulatory Acceptance Criteria and Guidance.................................................... 11 3.0 Instrumentation Selection Process ............................................................................. 13 3.1 Phase 1 ............................................................................................................... 13 3.2 Phase 2 ............................................................................................................... 13 3.3 Phase 3 and Phase 4 .......................................................................................... 14 4.0 Temperature Measurement in the NPM ....................................................................... 15 4.1 Narrow Range Reactor Coolant System Hot Temperature .................................. 18 4.2 Wide Range Reactor Coolant System Hot Temperature ..................................... 20 4.3 Narrow Range Reactor Coolant System Cold Temperature ................................ 22 4.4 Wide Range Reactor Coolant System Cold Temperature ................................... 24 4.5 Pressurizer Liquid Temperature........................................................................... 26 4.6 Pressurizer Vapor Temperature ........................................................................... 28 4.7 Containment Air Temperature .............................................................................. 29 4.8 Main Steam Temperature .................................................................................... 31 4.9 Feedwater Temperature ...................................................................................... 33 4.10 Decay Heat Removal System Outlet Temperature .............................................. 35 4.11 Under-the-Bioshield Temperature........................................................................ 37 5.0 Pressure Measurement in the NPM ............................................................................. 39 5.1 Pressurizer Pressure ........................................................................................... 41 5.2 Wide Range Reactor Coolant System Pressure ................................................. 43

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 Licensing Technical Report 5.3 Narrow Range Containment Pressure................................................................. 45 5.4 Wide Range Containment Pressure .................................................................... 47 5.5 Main Steam Pressure .......................................................................................... 49 5.6 Feedwater Pressure/Decay Heat Removal System Outlet Pressure .................. 51 6.0 Reactor Coolant System Flow ..................................................................................... 54 6.1 Reactor Coolant System Flowmeter .................................................................... 55 7.0 Level Measurement in the NPM ................................................................................... 58 7.1 Pressurizer Level and Reactor Pressure Vessel Riser Level .............................. 59 7.2 Containment Water Level .................................................................................... 62 7.3 Decay Heat Removal System Level .................................................................... 64 8.0 Summary and Conclusions .......................................................................................... 67 9.0 References ..................................................................................................................... 69 9.1 Industry and Regulatory Standards ..................................................................... 69

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 Licensing Technical Report TABLES Table 1-1 Abbreviations ......................................................................................................... 6 Table 1-2 Definitions .............................................................................................................. 7 Table 4-1 Temperature Sensor List ..................................................................................... 16 Table 5-1 Pressure Sensor List ........................................................................................... 40 Table 6-1 RCS Flowmeter ................................................................................................... 55 Table 7-1 Pressurizer/RPV/CNV Water Level ..................................................................... 59

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 Abstract The NuScale Power, LLC (NuScale) design poses unique challenges for sensor selection because of its small size, integral pressurized water reactor vessel, and high pressure containment. This document, Nuclear Steam Supply System Advanced Sensor Technical Report, TR-0316-22048, Revision 1, describes NuScales approach to assure that the appropriate temperature, pressure, flow and level sensors are selected on the basis of their requirements, operation, installation, maintenance, and qualification. The approach draws on requirements identified in NuScale documents, safety analyses, Nuclear Regulatory Commission (NRC) design criteria, American Society of Mechanical Engineers (ASME) standards, and Institute of Electrical and Electronics Engineers (IEEE) standards. This report addresses all vessel-related sensor types being considered for use in the NuScale small modular reactor.

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 Executive Summary The NuScale Power, LLC (NuScale) design poses unique challenges for sensor selection because of its small size, integral pressurized water reactor vessel, and high pressure containment. This document, Nuclear Steam Supply System Advanced Sensor Technical Report, TR-0316-22048, Revision 1, describes NuScales approach to assure that the appropriate temperature, pressure, flow and level sensors are selected on the basis of their requirements, operation, installation, maintenance, and qualification. The approach draws on requirements identified in NuScale documents, safety analyses, Nuclear Regulatory Commission (NRC) design criteria, American Society of Mechanical Engineers (ASME) standards, and Institute of Electrical and Electronics Engineers (IEEE) standards. This report addresses all vessel-related sensor types being considered for use in the NuScale small modular reactor.

The NSSS sensors that are adjacent to the reactor pressure vessel (RPV), the containment vessel (CNV), or associated piping on the vessel side of the NuScale Power Module (NPM) of any disconnection point, are included in this report. The report also includes the under-the-bioshield temperature sensors that are mounted to the module operating bay reactor pool wall.

Functions associated with the NPM sensors are included in this report. Those functions include post-accident monitoring (PAM), reactor trip systems (RTS), engineered safety features actuation system (ESFAS), low temperature overpressure protection (LTOP), core cooling indications, main control room (MCR) indication, alarms, plant historian, and NSSS control.

As an initial part of the sensor selection process, a habitability study was performed to evaluate the NSSS sensor and associated transmitter locations for survivability in the NPM. This study used estimated values for temperature, pressure, and radiation to assess the viability of conventional sensor use in the NPM. Under normal conditions, the small size of the CNV and RPV creates a unique environment. During normal operation, the instrumentation experiences a more severe temperature and radiation environment than the instrumentation used in a conventional pressurized water reactor. In the event of a design-basis accident (DBA), the radiation, temperature, and pressure levels in the CNV become significantly higher, which creates a unique environment in which the safety-related instrumentation must continue to function.

After analyzing multiple options, the conclusion from the habitability study was that the most suitable solution for instrumenting the NPM would be to find, or manufacture, radiation-hardened sensors paired with remote electronics located outside the bioshield area or run sensing lines to conventional instruments that would be located inside a pressure boundary enclosure located outside containment.

To overcome the aspects of the NPM small size and restrictive environment, NuScale is implementing a four-phase approach for sensor selection as follows:

Phase 1 - Technology Selection

Phase 2 - Proof-of-Concept

Phase 3 - Collaborative Product Development

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1

Phase 4 - Environmental Qualification Phase 1 has been completed for the four primary process variables of interest: temperature, flow, pressure, and level. This technical report discusses the results of Phase 1 for each of the process variables.

Phase 2 for reactor coolant system (RCS) flow measurement, pressurizer (PZR) level, RPV riser level measurement, CNV water level measurement, and pressure measurement is

((2(a)(b) The Phase 2 evaluation for resistance temperature detectors (RTDs) is not needed because RTDs are an existing nuclear qualified device and are expected to meet the NuScale predicted environments with minimal modification. ((

                                          }}2(a)(b)

NuScale locates some of the NPM sensors adjacent to the RPV, most of which are in the CNV, and plans to use first-of-a-kind (FOAK) nuclear sensor technology that may contain digital signal processing equipment. This report addresses the path taken to-date and describes the FOAK technologies as well as the conventional technologies to be utilized. This report describes the sensor technologies and their functions, maintenance, installation, qualification, and future work. The sensor descriptions of the valve position indications, the neutron monitoring system (ex-core) sensors, the in-core instrumentation, the PAM radiation monitors, the bus voltage monitors, and the rod position indication sensors are provided by their respective manufacturers or system owners and are not within the scope of this report because they are mature technologies. Temperature Measurement Temperature, pressure, and radiation levels in the NPM containment are higher than in conventional large pressurized water reactors, ((

                                                                                  }}2(a)(c) The Phase 1 report for temperature measurement recommended ((
                                                           }}2(a)(c)

Pressure Measurement An unconventional pressure measurement device was selected that provided an in-containment method of measuring pressure. This device uses an inside containment pressure transducer with remote processing electronics. ((

                                                                                                    }}2(a)(c)

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 ((

                                                                               }}2(a)(c) and environmental qualification.

Flow Measurement The (( }}2(a)(c)(d) has been selected to measure RCS flow. The ((

            }}2(a)(c)(d) was contracted to perform a Phase 1 preliminary evaluation of their

(( }}2(a)(c) could be converted and installed on the NuScale vessel to measure RCS flow. The results of Phase 1 justified proceeding to a Phase 2 proof-of-concept study, which is in progress. As part of the Phase 2 flow measurement project, a ((

                                                                    }}2(b)(c)

Level Measurement A Phase 1 study was undertaken to explore methods for the measurement of containment water level, pressurizer level, and RPV riser reactor level. ((

                                                                                                    }}2(a)(c)

The baseline level measurement concept being pursued for the NuScale design is a ((

                                            }}2(a)(c) is remote from the sensor assembly and located in a mild environment.

Summary Sensor development for the new unconventional sensor functions is underway. Current NuScale contracts with companies such as (( }}2(c)(d) Ultra Electronics are pursuing this work. As the sensor requirements and concept design become more mature, the details of this sensor definition will be captured in updated revisions of the NSSS sensor architecture report, in the appropriate drawings, and in the respective system design description documents. © Copyright 2018 by NuScale Power, LLC 4

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 1.0 Introduction 1.1 Purpose The purpose of this Nuclear Steam Supply System (NSSS) Advanced Sensor Technical Report is to describe NSSS sensor requirements, design concepts, performance capabilities, locations, maintenance approach, and qualification plans. This report also identifies the areas that need further investigation or study. The information contained in this report is the latest definition and understanding of NSSS sensors. It draws on requirements identified in NuScale documents, safety analyses, NRC design criteria, and industry standards. 1.2 Scope This technical report describes the baseline approaches NuScale has taken to measure the NSSS process variables: flow, temperature, pressure, and level. This report addresses the work accomplished to-date, the first-of-a-kind (FOAK) technologies, and the conventional technologies to be utilized. This report describes sensor technology, its applications, maintenance, installation, and spares philosophy, which are based on the NuScale environmental specifications for containment, reactor pool, and under-the-bioshield environments. Functions associated with the NSSS sensors are included in this report. Those functions include post-accident monitoring (PAM), ((

                                                                                                     }}2(c)

The structure of the conceptual development for each sensor function is outlined below. The items that need further development or research are identified at the end of each concept description in a section entitled Future Work. These items identify instrumentation scope for follow-on internal NuScale engineering work and external vendor contracts. The sensor descriptions of the valve position indications, the neutron monitoring system (ex-core) sensors, the in-core instrumentation, the PAM radiation monitors, the voltage monitoring sensors, and the rod position indication sensors are provided by their respective manufacturers or systems and are not included in the scope of this report. This report is divided into sensor functional groups: temperature, pressure, flow, and level. The following topics are developed within each sensor group:

Sensor Requirements
Sensor Functions
Baseline Concept Summary Location

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 Installation Maintenance Qualification

Future Work 1.3 Abbreviations Table 1-1 Abbreviations Term Definition 10 CFR 50 Title 10, Code of Federal Regulations, Part 50 ASME American Society of Mechanical Engineers CCF common-cause failure CFD computational fluid dynamics CNV containment vessel CVCS chemical and volume control system DBA design basis accident DBE design basis event DHR decay heat removal DHRS decay heat removal system EPA electrical penetration assembly ESFAS engineered safety feature actuation system FOAK first-of-a-kind FW feedwater FWIV feedwater isolation valve GDC general design criteria I&C instrumentation and controls ICI in-core instrumentation IEEE Institute of Electrical and Electronics Engineers

(( }}2(a)(c) LTOP low temperature over-pressure protection MCR main control room MCS module control system MI mineral insulated MPS module protection system MS main steam MSIV main steam isolation valve NPM NuScale Power Module NR narrow range NRC Nuclear Regulatory Commission NSSS nuclear steam supply system © Copyright 2018 by NuScale Power, LLC 6

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 Term Definition PAM post-accident monitoring psia pounds per square inch absolute PZR pressurizer RCS reactor coolant system RG Regulatory Guide RPV reactor pressure vessel RTD resistance temperature detector RTS reactor trip system SG steam generator WR wide range

     °F                            degree Fahrenheit
     %                             percent Table 1-2       Definitions Term                                                   Definition NSSS control                  NSSS control is the control system that regulates and controls plant parameters for normal operation, specified operational transients, and plant unanticipated events. These control loops include reactor control, pressurizer level and pressure control, feedwater/main steam control, as well as many others. In the NuScale nomenclature, the NSSS control system is referred to as the module control system (MCS).

sensor accuracy Sensor accuracy in this report is a value arrived at by engineering judgment based on known or similar sensor reference accuracies including estimated drift and temperature effects. It does not include measurement and test equipment (M&TE) uncertainties, process uncertainties, or any uncertainties contributed by other equipment in the loop. Thot The reactor cooling water temperature at the top of the RPV riser assembly (beneath the pressurizer baffle plate) Tcold The temperature of the reactor cooling water below the steam generators top of containment The area inside containment in the top 1/4 of the containment vessel underneath the The area outside containment, on the top section above the reactor bioshield pool water level and underneath the bioshield © Copyright 2018 by NuScale Power, LLC 7

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 2.0 Background The NuScale Power Module (NPM) is an innovative design based on over 50 years of practical application of light water-cooled pressurized water reactor technology. The NPM is a self-contained system composed of a reactor core, a pressurizer (PZR), and two steam generators (SG) integrated within the reactor pressure vessel (RPV) and housed in a compact steel containment vessel (CNV). The NPM is designed to operate efficiently at full-power conditions using natural circulation as the means of providing core coolant flow, eliminating the need for reactor coolant pumps. The NPM is partially immersed in a reactor pool and protected by passive safety systems. The small size of the CNV creates unique constraints in that most of the instrumentation is located in the RPV and the CNV and is in close proximity to radiation and high temperature under normal conditions. Under normal conditions, the instrumentation experiences a more severe environment than the instrumentation in a conventional pressurized water reactor. In the event of a design-basis accident, the radiation levels in the CNV become significantly higher, which creates a unique environment in which the instrumentation must continue to function. NuScale developed a habitability report that addressed the survivability and habitability of sensors located in containment and underneath the bioshield, based on environmental specifications. This report showed that the in-containment enclosure approach to sensor habitability, which was part of the previous baseline design, would not provide the temperature or radiation protection required to locate conventional pressure sensors in containment. In addition to sensor research and development, NuScale investigated a design for a connector that is capable of withstanding the NuScale containment temperatures and pressures while providing a hermetically sealed electrical connection. This connector is used to provide the sensor to cable connection in containment. It may also be used outside of containment. The connector is designed to be made of materials that are radiation tolerant. Research into sustainable electric cables that could operate in the containment environment was also pursued. A Phase 1 report was issued that recommended mineral insulated (MI) cables for all cabling inside containment. To overcome the difficulties associated with providing instrumentation for the vessel, NuScale implemented a four-phase process for sensor selection as follows. Phase 1 - The intent of Phase 1 was to perform an industry wide review of the instrumentation available for each of the four process variables with the goal of selecting instruments or types of instruments that appear to be eligible for qualification and to meet the process requirements associated with the NPM. © Copyright 2018 by NuScale Power, LLC 8

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 Phase 2 is a proof-of-concept phase performing tests on the instruments selected in Phase 1 to validate their ability to meet the criteria for service in the NPM excluding qualification. Phase 2 developments for RCS flow measurement, pressurizer level, RPV riser level measurements, containment water level, and vessel-related pressure measurement are (( }}2(a)(b) Because nuclear qualified resistance temperature detectors (RTD) were selected for temperature measurement, no Phase 2 proof-of-concept is necessary for temperature measurement. RTD development proceeds directly to Phase 3. Phase 3 involves collaborative product development between NuScale and the selected vendor for each process variable to prepare the instruments for qualification. Phase 3 schedules for the (( }}2(c) Phase 4 is used to qualify the various instruments for harsh environment service in the NPM. A ((

                                                                   }}2(a)(b) Radiation aging, including design basis event dose, consumes the greatest amount of time in the qualification process. NuScale has new qualification programs for some sensors that use FOAK sensor technology and experience new pressure, temperature, and radiation environments.

2.1 Technology Conventional sensing technology was analyzed initially to maximize the experience and qualification of currently fielded devices; however, in many cases the conventional devices did not offer viable solutions for the NuScale containment environment. At the conclusion of the Phase 1 studies, conventional technology was chosen for temperature sensors, and outside containment temperature and pressure sensors, but the other in-containment sensors solutions required new technology. The new technology sensing methods are detailed in this report. 2.2 Spares In general, no installed spares are utilized in any measurement requirement. This decision was to minimize the number of in-containment and near containment sensors and to minimize cables going through the containment penetrations. If an in-containment sensor requires replacement, the only opportunity is in the refueling dry dock. One exception to the above statement is the narrow range hot and cold temperature sensors. These sensors have more than one measurement per separation group. This was done to develop an averaging process to minimize thermal streaming effects that could create varied temperatures in the different sensor groups. NuScale is planning for the processing algorithm for the averaging function to include the ability to drop out a failed RTD from the average, thus sustaining an on-line failure with no interruption in service. © Copyright 2018 by NuScale Power, LLC 9

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 2.3 Assumptions and Design Guidance The following assumptions are applicable to the NuScale advanced sensor described in this report.

All instruments are accessible, retrievable, and replaceable while in the refueling bay dry dock.
All in-vessel instruments described shall be capable of calibration and capable of an in-situ function test upon vessel return to the operating bay.
Space is provided for electronics associated with sensors on or near the platform, above the containment head or in an electronics room.
Sensors located in the top of containment or underneath the bioshield are protected, shielded, or located away from the impact spray effects of a high energy line break by pipe whip restraints, local shielding, or sensor location.
The decay heat removal system (DHRS) condenser is capable of supporting the mass of the submerged pressure, temperature, and level sensors.

The following design guidance applies to the design of the NuScale advanced sensors.

Taps or sensing lines through the containment vessel wall are not possible without moving the containment pressure boundary around them or adding double isolation.
The vessel sensors meet the requirements of 10 CFR 50.34(f)(2)(xviii),

Reference 9.1.2, in regards to providing an unambiguous indication of inadequate core cooling.

The sensor accuracy and sensor response time requirements detailed in this report are the result of ((

                                                             }}2(a)(c)

All sensor supporting structures planned for insertion in the RPV (as part of the RPV pressure boundary) are classified as Seismic Category I. The seismic requirement classification in sections 4, 5, 6, and 7 of this report is for the sensor or sensing element only and does not apply to the thermowells, guide tubes, or other sensor supporting structures.

2.4 Alternative Sensor Options Through the process of investigation of suitable sensors for the NPM design, many technologies were investigated. A Phase 1 contract with ((

                                                                                                      }}2(c)(d)

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 ((

                                                                                                    }}2(c)(d)

Many of these technologies showed promise for NPM sensor measurements; however, they were not chosen as the baseline option due to the immaturity of design or potential increased development risk. These technologies remain as back-up options for the NuScale design, in the event that a current baseline option becomes unsuitable. 2.5 Regulatory Acceptance Criteria and Guidance

Title 10 Code of Federal Regulations, Part 50 (10 CFR 50), Appendix A, General Design Criteria (GDC) 2 Design Basis for Protection Against Natural Phenomena sets requirements for the qualification of structures, systems, and components important to safety in the event of earthquakes, tornadoes, hurricanes, floods, tsunami, and seiches.
10 CFR 50, Appendix A, GDC 4, Environmental and Dynamic Effects Design Bases sets the requirements for systems, structures, and components important to safety such that they are designed to accommodate the effects of environmental conditions associated with normal operations, maintenance, testing, and postulated accidents.
10 CFR 50.49, Environmental Qualification of Electric Equipment Important to Safety for Nuclear Power Plants sets the qualification requirements for instrumentation and controls (I&C) equipment in harsh environments. Regulatory Guide (RG) 1.89, Revision 1, Qualification of Class 1E Equipment for Nuclear Power Plants, provides methods found acceptable by the NRC for complying with the requirements of 10 CFR 50.49. RG 1.89 endorses IEEE Standard 323-1974, Qualifying Class 1E Equipment for Nuclear Power Generating Station as accepted guidance on equipment qualification for harsh environments.
U.S. NRC RG 1.209, Guidelines for Environmental Qualification of Safety-Related Computer Based Instrumentation and Control Systems in Nuclear Power Plants, specifies additional requirements for safety related digital I&C components located in a mild environment. RG 1.209 endorses IEEE Standard 323-2003 IEEE Standard for Qualifying Class 1E Equipment for Nuclear Power Generating Stations, as accepted guidance on equipment qualification for mild environments.
U.S. NRC RG 1.206, Combined License Applications for Nuclear Power Plants, June 2007, notes in Section C.I.1.5 that the NRC expects additional technical information (beyond that in the application), including items such as verification of unique design concepts.
10 CFR 52.47, Contents of Applications; Technical Information, specifies that an application must contain a sufficient level of design information. 10 CFR 52.47(a)(2)(i) puts emphasis on the extent to which the reactor incorporates unique, unusual or enhanced safety features having a significant bearing on the probability or consequences of accidental release of radioactive materials.
IEEE Standard 379-2000, Application of the Single-Failure Criterion to Nuclear Power Generating Station Safety Systems, provides methods acceptable to the NRC staff for satisfying the NRC regulations with respect to the application of the

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 single-failure criterion to the electrical power, instrumentation, and control portions of nuclear power plant safety systems. RG 1.53, Revision 2, Application of the Single-Failure Criterion to Safety Systems, endorses IEEE Standard 379-2000 as accepted guidance for satisfying the single failure criterion.

IEEE Standard 344-2004, IEEE Recommended Practice for Seismic Qualification of Class 1E Equipment for Nuclear Power Generating Stations, provides generally accepted methods for the seismic qualification of electrical equipment in new nuclear power plants. RG 1.100, Revision 2, Seismic Qualification of Electrical and Active Mechanical Equipment and Functional Qualification of Active Mechanical Equipment for Nuclear Power Plants, endorses IEEE Standard 344-2004 as accepted guidance for the seismic qualification of electrical equipment.
IEEE Standard 603-1991, IEEE Standard Criteria for Safety Systems for Nuclear Power Generating Stations, section 5.4 requires that safety equipment be qualified by type test, previous operating experience, or analysis, or any combination of these three methods. IEEE Standard 603-1991 is incorporated by reference into 10 CFR 50.55a(h), Protection and safety systems.
IEEE Standard 7.4.3.2-2003, IEEE Standard Criteria for Digital Computers in Safety Systems of Nuclear Power Generating Stations, section 5.4 provides additional guidance for the qualification of digital I&C equipment. RG 1.152, Revision 3, Criteria for Use of Computers in Safety Systems of Nuclear Power Plants, endorses IEEE Standard 7.4.3.2-2003.
10 CFR 50, Appendix A, GDC 13, Instrumentation and Control, requires there to be instrumentation to monitor variables over the anticipated ranges of normal operation, for anticipated operational occurrences, and for accident conditions.

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 3.0 Instrumentation Selection Process 3.1 Phase 1 In 2015, Ultra Electronics, Nuclear Sensors and Process Instrumentation (hereinafter referred to as Ultra Electronics), performed a Phase 1 study for sensor technology selection for each of the four process variables and the results of those studies constitute part of the basis for this report. Studies were performed for NuScale on instrument habitability in the containment, pressure measurement options, level measurement options, MI and other hardened cables, temperature measurement, and an in-vessel connector concept. Ultra Electronics was selected for their decades-long experience in nuclear plant instrumentation and their ability to engineer and re-engineer unique nuclear quality sensors. They supply instrumentation to more than 113 reactors in 16 countries. NuScale has worked with Ultra Electronics since 2012, when the vendor first started considering in-vessel instrumentation that would work with the NuScale design. The selected vendor has an established 10 CFR 50, Appendix B Nuclear Quality program, and they have the resources and facilities to design, build, and qualify nuclear instrumentation. During the period 2014 through 2015, ((

                                                      }}2(a)(c)(d) Based on the Phase 1 results, NuScale has proceeded with a Phase 2 ((                                      }}2(a)(b) The Phase 2 proof-of-concept phase is currently underway.

In Phase 1 Ultra Electronics ((

                                                                                                    }}2(c)(d) 3.2      Phase 2 The RCS flow instrumentation is actively undergoing Phase 2 development at this time.

((

                                         }}2(a)(b) The objective is to provide a ((
                         }} 2(a)(b) obtaining data over flow ranges corresponding to 0 percent to 110 percent of estimated full flow.

((

                                                                                  }}2(a)(b)

A contract has been issued for Phase 2 development of RPV and CNV level. The intent of this phase is to analyze and test various commercially available systems, with the objective of choosing the product(s) for use in the NPM. Ultra Electronics, as the overseer of the test effort, is responsible for constructing test chambers and testing © Copyright 2018 by NuScale Power, LLC 13

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 various level detectors to determine which models for further development. Ultra Electronics is also responsible for evaluating ((

                                                                      }}2(a)(c) An additional part of the Phase 2 effort is currently planned for testing the ability of systems to accurately measure level under operating temperature and pressure.

A radiation hardened and temperature tolerant pressure transducer with remote electronics was recommended for in-vessel pressure measurement in the Ultra Electronics pressure report in Phase 1. Several product options were recommended for this sensor selection. Once the sensor selection is complete, Phase 2 work will begin on in-vessel pressure sensing devices. RTDs that are currently available were selected for temperature measurement and are currently available. Consequently, no proof-of-concept phase (i.e., Phase 2) is needed for them. 3.3 Phase 3 and Phase 4 There are ((

                                                        }}2(a)(b)

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 4.0 Temperature Measurement in the NPM The purpose of the Phase 1 temperature study for NuScale was to present conceptual designs for in-vessel temperature measurement that meets the requirements of the NPM. The scope of the report was to develop approaches for measuring the following.

1. Narrow range RCS hot temperature (NR RCS Thot)

2. Wide range RCS hot temperature (WR RCS Thot)

3. Narrow range RCS cold temperature (NR RCS Tcold)

4. Wide range RCS cold temperature (WR RCS Tcold)

5. Pressurizer liquid temperature

6. Pressurizer vapor temperature

7. CNV air temperature

8. Main steam (MS) temperature

9. Feedwater temperature

10. DHRS outlet temperature

11. Under-the-bioshield temperature

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 Table 4-1 Temperature Sensor List Temperature Safety/Risk Range Quantity Function Location Sensors Classification Top of Narrow range 400°F to 12 RTS/ESFAS A1 downcomer RCS hot 650°F ESFAS T-4 interlock temperature Wide range 40°F to 4 PAM Type B Top of A1 RCS hot 700°F downcomer ESFAS T-1 and T-2 temperature interlocks Subcooling monitor Core cooling indication MCR indication Plant historian Narrow range 400°F to 8 NSSS control Downcomer B2 RCS cold 650°F below MCR indication temperature feedwater Plant historian inlets Input to calorimetric calculation Wide range 40°F to 4 LTOP T-1 enable Downcomer A2 RCS cold 700°F below Subcooling monitor temperature feedwater Core cooling indication inlets MCR indication Plant historian PZR liquid 40°F to 2 MCR indication Lower PZR B2 temperature 800°F Plant historian PZR vapor 40°F to 2 NSSS control Upper PZR B2 temperature 800°F MCR indication Plant historian © Copyright 2018 by NuScale Power, LLC 16

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 Temperature Safety/Risk Range Quantity Function Location Sensors Classification CNV air 40°F to 2 NSSS control Upper part of B2 temperature 600°F containment MCR indication Plant historian Main steam 100°F to 8 RTS/ESFAS Upstream of A1 temperature 700°F main steam PAM Type D (DHR inlet isolation temperature) Input to calorimetric valve (MSIV) calculation on MS pipe MCR indication NSSS control Plant historian Feedwater 40°F to 6 NSSS control Downstream B2 temperature 440°F of feedwater MCR indication isolation Input to calorimetric valve (FWIV) calculation on feedwater (FW) pipe Plant historian DHRS outlet 40°F to 4 PAM Type D Bottom of B2 temperature 440°F DHRS unit MCR indication Plant historian Under-the- 40°F to 4 RTS/ESFAS Under the A1 bioshield 700°F bioshield PAM Type D temperature MCR indication Plant historian © Copyright 2018 by NuScale Power, LLC 17

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 4.1 Narrow Range Reactor Coolant System Hot Temperature 4.1.1 Sensor Functions The primary function of the narrow range reactor coolant system (RCS) hot temperature sensors is to provide temperature measurements for the narrow range RCS hot temperature reactor trip, DHRS actuation, and NSSS control functions. To obtain an accurate indication, multiple sensors are required. By taking multiple narrow range RCS hot temperature measurements at several locations in the quadrant and averaging them, an accurate measurement is achievable. The averaging process is expected to compensate for any streaming effects that may be present at the top of the RPV riser. Narrow range RCS hot temperature functions:

reactor trip - High RCS hot temperature
ESFAS - DHRS actuation - High RCS hot temperature
ESFAS - T-4 interlock
NSSS control
input to primary side calorimetric calculation
MCR indication
plant historian 4.1.2 Sensor Requirements Safety classification: A1 Seismic classification: Category I Range: 400 to 650 degrees Fahrenheit Sensor accuracy: +/- (( }}2(a)(c) degrees Fahrenheit Sensor response time: < 6 seconds Quantity: twelve (four separation groups of three sensors each) 4.1.3 Baseline Concept 4.1.3.1 Summary Three narrow range RCS hot temperature RTDs signals per RCS quadrant are sent to the module protection system (MPS) which implements signal conditioning algorithms to determine an average temperature value for each quadrant. An average hot temperature signal is preferable to a single signal to compensate for the temperature streaming effects in the RCS flow.

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 4.1.3.2 Location The RTDs are located in thermowells that intersect the reactor coolant flow path, below the pressurizer baffle plate and upstream of the helical coil section of the tube bundles of the steam generators. These thermowell inserts are located in quadrants that form separation groups around the pressure vessel. The RTDs are not directly exposed to the RPV environment as they are mounted in thermowells. However, they will need to be conservatively qualified for the containment environment. 4.1.3.3 Installation The sensors are installed in thermowells on the RPV vessel and inside containment. The RTD signals are routed through containment with MI cabling so that the signals can withstand normal and design basis event (DBE) environments. A total of twelve sensing elements, three per separation group, are planned. They are mounted below the pressurizer baffle plate section to obtain safety-related Thot narrow range temperature measurement. For this baseline configuration, one of the three narrow range RTDs share a thermowell with the wide range RTD as a dual element wide range (WR)/narrow range (NR) RTD in each quadrant to minimize the number of thermowell installations in the vessel. The precise RTD location within the quarter section of RPV and the depth of the RTD extension into the RPV annulus has not yet been determined. In depth flow analysis with modelled temperature streaming will be evaluated for this determination, and is captured in the future work section below. 4.1.3.4 Maintenance The temperature elements are mounted and cables routed such that maintenance can be performed. The sensors are accessible while the module is in the refueling bay dry dock and have the ability to be maintained, removed, and reinstalled. An RTD cross calibration is required before or after the refueling outage. The calibration requires access to the MPS cabinets and an RTD cross calibration test set. An in-situ function test is also being planned for post-dry dock testing after the vessel has been moved back to its operating bay. The RTD cross calibration is performed in accordance with procedures in the licensees maintenance program and the plant technical specifications. The method for performing the RTD cross calibration for the NuScale design is similar to those used in other designs. The RTD resistance measurements are compared to each other and traced to laboratory calibration data at various temperatures during plant heat-up and cool-down. Acceptance criteria are determined based on vendor specifications for the RTDs and the plant safety analysis. The test acceptance criteria specify a limit within which no action is required, a limit within which a new calibration curve can then be determined for the RTD based on measured data, and a limit which requires the RTD to be declared inoperable and repaired or replaced. © Copyright 2018 by NuScale Power, LLC 19

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 4.1.3.5 Qualification The NR RCS hot temperature RTDs and respective cables will be conservatively qualified to operate in the containment normal conditions and DBE conditions in accordance with industry standards. 4.1.4 Future Work

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                                                                                       }}2(a)(b) 4.2      Wide Range Reactor Coolant System Hot Temperature 4.2.1    Sensor Functions The primary function of the wide range RCS hot temperature measurement is to provide the full range temperature monitoring for PAM and operator display.

Wide range RCS hot temperature functions:

PAM Type B variable
ESFAS - T-2 and T-3 interlocks
core cooling indication
MCR indication
plant historian 4.2.2 Sensor Requirements Safety classification: A1 Seismic classification: Category I

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 Range: 40 to 700 degrees Fahrenheit Sensor accuracy: +/- (( }}2(a)(c) degrees Fahrenheit Sensor response time: < 6 seconds Quantity: Four RTDs (one per quadrant) 4.2.3 Baseline Concept 4.2.3.1 Summary The wide range RCS hot temperature RTDs have a wide range of measurement (40 degrees Fahrenheit to 700 degrees Fahrenheit) and are installed in thermowells shared with one narrow range RTD per quadrant. The RTD leads are routed from the sensor up to the containment head, through the electrical penetration assemblies (EPAs) on the CNV head, and then to the MPS electronics cabinets. 4.2.3.2 Location The wide range RTDs are located in thermowells that intersect the reactor coolant flow path, below the pressurizer baffle plate and upstream of the steam generators. These thermowell inserts are located in quadrants that form separation groups around the pressure vessel. The RTDs themselves are not exposed to the RPV environment, but will be conservatively qualified for the containment environment. 4.2.3.3 Installation Four RTDs total, with one per separation group, are installed in thermowells below the pressurizer baffle plate section to obtain the temperature measurement. These RTDs are installed in thermowells on the containment side of the RPV and will be conservatively qualified to operate in the containment normal and DBE environments. For this baseline configuration the wide range RTD shares a thermowell with one of the narrow range RCS hot temperature RTDs (as a dual element WR and NR RTD) in each quadrant to minimize the number of thermowell installations in the vessel. These RTDs measure the reactor coolant temperature through the thermowell. The RTD signals are routed through containment with MI cabling so that the signals can withstand normal and DBE environments. 4.2.3.4 Maintenance The temperature elements are mounted and cables are routed such that maintenance can be performed. The sensors are accessible while the module is in the refueling bay dry dock and have the ability to be maintained, removed, and reinstalled. An RTD cross calibration is required before or after the refueling outage. The calibration requires access to the MPS cabinet and an RTD cross calibration test set. An in-situ © Copyright 2018 by NuScale Power, LLC 21

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 RTD test is also performed to ensure functionality of the RTD after the move back to the reactor pool. The cross-calibration will be performed as described in Section 4.1.3.4. 4.2.3.5 Qualification The wide range RCS hot temperature RTDs and respective cables will be conservatively qualified to operate in the containment normal conditions and DBE conditions in accordance with industry standards. These RTDs are designed to operate in normal containment conditions and containment DBE pressure, temperature, radiation conditions, and conditions associated with the post-accident duration requirements. The associated cabling and connectors are designed and tested for the same normal and DBE conditions. 4.2.4 Future Work

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                                                                                        }}2(a)(b) 4.3      Narrow Range Reactor Coolant System Cold Temperature 4.3.1    Sensor Functions The primary functions of the RCS narrow range cold temperature sensors are to acquire temperature measurements for MCR indication, primary side calorimetric calculations, and to compute the average temperature calculation for NSSS control functions. The narrow range RTD signals require multiple sensors to average and adequately acquire the average temperature. The reactor coolant is expected to be well mixed after passing though the steam generators; however, there may still be thermal streaming effects. An averaging scheme compensates for those effects.

Narrow range RCS cold temperature functions:

NSSS control - computation of average temperature for control functions

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1

input to primary side calorimetric calculation
MCR indication
plant historian 4.3.2 Sensor Requirements Safety classification: B2 Seismic classification: Category II Range: 400 to 650 degrees Fahrenheit Sensor accuracy: +/- (( }}2(a)(c) degrees Fahrenheit Sensor response time: < 6 seconds Quantity: Eight (four channels of two sensors each) 4.3.3 Baseline Concept 4.3.3.1 Summary Two narrow range RTD signals per RPV quadrant are sent to the MCS that implement signal conditioning algorithms to determine an average reactor coolant system cold temperature value for each quadrant. An average RCS cold temperature signal is preferable to a single RCS cold temperature signal to compensate for temperature streaming effects in the RCS.

4.3.3.2 Location The narrow range RTDs are located in thermowells on the side of the RPV in the lower downcomer region near the ultrasonic flow sensors. These thermowell inserts are located in quadrants around the pressure vessel in the lower downcomer region. The thermowells are the pressure boundary between the RPV and CNV environments. The RTDs are not exposed to the RPV environment, but will be conservatively qualified for the containment environment. The RTD leads are routed up to the containment head using MI cable, through the EPAs on the CNV head, and then to the MCS electronics cabinets. 4.3.3.3 Installation Eight RTDs, two per channel, are mounted in thermowells below the steam generators. The RTD leads are routed to the EPAs on the containment head. From there, the RTD cables are routed to the MCS electronics cabinets located in a mild environment. For this baseline configuration one of the two narrow range RTDs share a thermowell with the wide range RTD (dual element WR and NR RTD) in each quadrant to minimize the number of thermowell installations in the vessel. © Copyright 2018 by NuScale Power, LLC 23

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 4.3.3.4 Maintenance The temperature elements are mounted and cables are routed such that maintenance can be performed. The RTDs are accessible while the module is in the refueling bay dry dock, and have the ability to be maintained, removed, and reinstalled. Their location on the exposed area between the CNV flange and the RPV flange allow for RTD removal or replacement, while in the refueling bay dry dock. An RTD cross calibration is required before or after the refueling outage. The calibration requires access to the MPS cabinet and an RTD cross calibration test set. An in-situ RTD test is also performed to ensure functionality of the RTD after the move back to the reactor pool. The cross-calibration will be performed as described in Section 4.1.3.4. 4.3.3.5 Qualification The narrow range RCS cold temperature RTDs and respective cables are designed for operability in the containment pressure vessel normal environment. 4.3.4 Future Work

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                                                                                        }}2(a)(b) 4.4      Wide Range Reactor Coolant System Cold Temperature 4.4.1    Sensor Functions The primary function of the wide range RCS cold temperature measurement is to provide the full range temperature monitoring for LTOP and operator display.

Wide range RCS cold temperature wide range functions:

LTOP (with wide range RCS pressure)
ESFAS T-1 interlock

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1

core cooling indication
MCR indication
plant historian 4.4.2 Sensor Requirements Safety classification: A2 Seismic classification: Category I Range: 40 to 700 degrees Fahrenheit Sensor accuracy: +/- (( }}2(a)(c) degrees Fahrenheit Sensor response time: < 6 seconds Quantity: Four temperature sensors (one per quadrant) 4.4.3 Baseline Concept 4.4.3.1 Summary The wide-range RCS cold temperature RTDs are inserted in thermowells located in the lower downcomer sharing thermowells with the narrow range RTDs. The wide range RTDs are exposed to the containment environment as the thermowell will act as the pressure boundary between the RPV and CNV environments.

4.4.3.2 Location The wide-range RTDs are located in thermowells located in the lower downcomer of the RPV, downstream of the steam generators. 4.4.3.3 Installation The wide-range RTDs are inserted in thermowells located in the lower downcomer section of the RPV. For this baseline configuration the wide range RTD shares a thermowell with one of the narrow range RTDs (as a dual element WR/NR RTD) in each quadrant to minimize the number of thermowell installations in the vessel. The RTD lead wires are routed through a support conduit to the CNV penetration assemblies. The RTD signals are routed through containment with MI cabling so that the signals can withstand normal and DBE environments. 4.4.3.4 Maintenance The RTDs are mounted and cables are routed such that maintenance can be performed. The sensors are accessible while the module is in the refueling bay dry dock and have the ability to be maintained, removed, and reinstalled. Their location on the exposed © Copyright 2018 by NuScale Power, LLC 25

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 area between the CNV flange and the RPV flange allow for RTD removal or replacement, while in the refueling bay dry dock. An RTD cross calibration is required before or after the refueling outage. The calibration requires access to the MPS cabinet and an RTD cross calibration test set. An in-situ RTD test is also performed to ensure functionality of the RTD after the move back to the reactor pool. The cross calibration will be performed as described in Section 4.1.3.4. 4.4.3.5 Qualification The LTOP function of these RTDs requires the RTDs to meet the harsh environment qualification requirements for the containment environment. 4.4.4 Future Work

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                                                                                        }}2(a)(b) 4.5      Pressurizer Liquid Temperature 4.5.1    Sensor Functions The primary function of the pressurizer temperature measurement is to provide pressurizer liquid temperature information for operator display and NSSS (start-up/shutdown) control.

Pressurizer liquid temperature measurement functions:

NSSS controls (startup/shutdown)
MCR indication
plant historian

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 4.5.2 Sensor Requirements Safety classification: B2 Seismic classification: Category II Range: 40 to 800 degrees Fahrenheit Sensor accuracy: +/- (( }}2(a)(c) degrees Fahrenheit Sensor response time: < 6 seconds Quantity: Two temperature sensors 4.5.3 Baseline Concept 4.5.3.1 Summary The pressurizer liquid temperature measurement provides indication to the MCR and plant historian for operational actions during start-up and shutdown. These RTDs are inserted into thermowells to ensure RPV pressure boundary conditions are met. 4.5.3.2 Location The pressurizer liquid temperature RTDs are located in thermowells above the pressurizer baffle plate and below the normal operating liquid level. These thermowell inserts are located in opposite quadrants around the pressurizer section of the RPV. 4.5.3.3 Installation The RTDs are mounted in thermowells in the lower section of the pressurizer. The RTD cabling is MI cable to protect the electronic signal from the containment environment conditions. The RTD wiring is routed from the RTD in the thermowell location to the designated containment vessel EPAs and then to the MCS cabinets located in a mild environment outside containment. 4.5.3.4 Maintenance The temperature elements are mounted and cables are routed such that maintenance can be performed. The RTDs and associated cabling have the ability to be removed and replaced while in dry dock during a refueling outage. The calibration methodology for these sensors is an item for the Future Work section below. 4.5.3.5 Qualification The pressurizer liquid temperature RTDs and respective cables will be designed to operate in containment normal operating conditions. © Copyright 2018 by NuScale Power, LLC 27

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 4.5.4 Future Work

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                                                                                            }}2(a)(b) 4.6      Pressurizer Vapor Temperature 4.6.1    Sensor Functions The primary function of the pressurizer vapor temperature sensor is to provide indication for operator display. This display is intended for operator use mainly during start up and shutdown operations. It also provides indication to the plant historian.

Pressurizer vapor temperature measurement functions:

NSSS controls
MCR indication
plant historian 4.6.2 Sensor Requirements Safety classification: B2 Seismic classification: Category II Range: 40 to 800 degrees Fahrenheit Sensor accuracy: +/- (( }}2(a)(c) degrees Fahrenheit Sensor response time: < 6 seconds Quantity: Two temperature sensors.

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 4.6.3 Baseline Concept 4.6.3.1 Summary The pressurizer vapor temperature measurement provides indication to the MCR and plant historian for operational actions during start up and shutdown. These RTDs are inserted into thermowells to ensure RPV pressure boundary conditions are met. 4.6.3.2 Location The pressurizer vapor temperature RTDs are located in thermowells near the top of the RPV to measure the vapor temperature of the pressurizer bubble. These thermowell inserts are located in opposite quadrants around the pressurizer section of the RPV. 4.6.3.3 Installation The two RTDs are installed in thermowells in the vapor section of the pressurizer. The RTD signals are protected from the containment environment by MI cables. The RTD cabling is routed from the RTD in the thermowell location to the designated containment vessel EPAs, and then to the MCS cabinets located in a mild environment outside containment. 4.6.3.4 Maintenance The temperature elements are mounted and cables are routed such that maintenance can be performed. The RTDs are accessible, and retrievable for necessary maintenance or replacement. The sensors and associated cabling have the ability to be removed and replaced while in dry dock during a refueling outage. The calibration methodology for these sensors is an item for the Future Work section below. 4.6.3.5 Qualification The pressurizer vapor temperature RTDs and respective cables will be designed to operate in containment normal operating conditions. 4.6.4 Future Work See Section 4.5.4 for the Future Work items associated with this sensor function. 4.7 Containment Air Temperature 4.7.1 Sensor Functions The primary function of the containment air temperature sensor is to provide general containment atmospheric temperature for operator display. It also provides indication to the plant historian and be available for NSSS control functions. Containment air temperature measurement functions: © Copyright 2018 by NuScale Power, LLC 29

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1

NSSS controls
MCR indication
plant historian 4.7.2 Sensor Requirements Safety classification: B2 Seismic classification: Category II Range: 40 to 600 degrees Fahrenheit Sensor accuracy: +/- (( }}2(a)(c) degrees Fahrenheit Sensor response time: < 6 seconds Quantity: Two temperature sensors 4.7.3 Baseline Concept 4.7.3.1 Summary The containment air temperature measurement provides indication to the MCR and plant historian for operational and trending purposes. These RTDs are expected to perform this measurement through mountings located on the inside of containment located in the upper part of containment. These RTDs do not perform a safety function, but will be designed to operate in the normal containment environment.

4.7.3.2 Location The containment air temperature RTDs are located on mountings on the inside of containment, near the top of the CNV to measure the air or vacuum temperature of the containment atmosphere. The mountings are positioned away from high-energy line break intensity areas. 4.7.3.3 Installation The two RTDs are installed on mountings near the top inside of containment. They are not housed in a thermowell, but are mounted such that the temperature sensing can occur in the environment which the RTD element resides. The RTD electrical leads are routed through the EPAs and then to the MCS electronics cabinets located in a mild environment. 4.7.3.4 Maintenance The temperature elements are mounted and cables are routed such that maintenance can be performed while in the refueling bay dry dock. The RTDs are accessible, and © Copyright 2018 by NuScale Power, LLC 30

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 retrievable for necessary maintenance and/or replacement. The sensors and associated cabling have the ability to be removed and replaced during a refueling outage. The calibration method for these RTDs has not yet been developed, and is added to the Future Work section below. 4.7.3.5 Qualification The containment air temperature RTDs and respective cables will be designed to operate in normal containment conditions. 4.7.4 Future Work

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                                                                            }}2(a)(b) 4.8      Main Steam Temperature 4.8.1    Sensor Functions The primary purpose of the main steam (MS) temperature sensor is to determine MS superheat for RTS/ESFAS actuations. This sensor is also required for MCR indication, calculations of the calorimetric, and NSSS control. The MS temperature measurement also serves as the DHRS inlet temperature measurement.

MS temperature measurement functions:

reactor trip - high steam superheat (with MS pressure)
reactor trip - low steam superheat (with MS pressure)
ESFAS - DHRS actuation - high steam superheat (with MS pressure)
ESFAS - DHRS actuation - low steam superheat (with MS pressure)
NSSS control
PAM Type D variable (DHRS inlet temperature)
input to secondary side calorimetric calculation
MCR indication
plant historian

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 4.8.2 Sensor Requirements Safety classification: A1 Seismic classification: Category I Range: 100 to 700 degrees Fahrenheit Sensor accuracy: +/- (( }}2(a)(c) degrees Fahrenheit Sensor response time: < 6 seconds Quantity: Eight (four RTDs per MS pipe, two MS pipes) 4.8.3 Baseline Concept 4.8.3.1 Summary The baseline concept for the MS temperature measurement is to use RTDs inserted in thermowells in the MS pipe sections on the upstream side of the MSIVs outside containment. Because the application is a pipe structure, conventional technology can be implemented. There are two MS pipes exiting containment with four thermowells per pipe. The eight sensing elements are routed to separation groups A, B, C, and D, in the MPS for calculation of steam superheat. The RTDs are made to fit in the thermowells, but otherwise the device is commercially available. 4.8.3.2 Location The location of the RTDs is in thermowells, outside of containment, underneath the bioshield, in the pipe section upstream of the MSIVs. 4.8.3.3 Installation The RTDs are installed in thermowells in the pipe section above the reactor pool level and underneath the bioshield. Conventional installation processes can be adapted for the location. 4.8.3.4 Maintenance The temperature elements are mounted and cables are routed such that maintenance can be performed. The RTDs are accessible and retrievable for necessary maintenance or replacement. The sensors and associated cabling have the ability to be retracted, relocated, or removed during refueling and the ability can be reinstalled when refueling is complete. The calibration methodology for these RTDs ((

                                                       }}2(a)(b)

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 4.8.3.5 Qualification The main steam RTDs and respective cables will be tailored for fit, with a qualification that envelopes the under-the-bioshield normal and DBE environment. 4.8.4 Future Work

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                                                             }}2(a)(b) 4.9      Feedwater Temperature 4.9.1    Sensor Functions The primary purpose of the feedwater temperature sensors is to determine feedwater temperature for indication in the MCR and for NSSS controls. This sensor is also required for plant historian and calorimetric calculations.

Feedwater temperature measurement functions:

NSSS control
input to secondary side calorimetric calculation
MCR indication
plant historian 4.9.2 Sensor Requirements Safety classification: B2 Seismic classification: Category II Range: 40 to 440 degrees Fahrenheit Sensor accuracy: +/- (( }}2(a)(c) degrees Fahrenheit Sensor response time: < 6 seconds Quantity: Six (three RTDs per FW pipe, two FW pipes)

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 4.9.3 Baseline Concept 4.9.3.1 Summary The baseline concept for the measurement of feedwater temperature is with RTDs in thermowells. Because the location of the device is outside of containment, the use of conventional means of temperature measurement is desired. An RTD of similar accuracy to the MS temperature sensors allows for similar accuracy when computing steam-feed delta temperature. There are two feedwater pipes going into containment and three feedwater RTDs on each pipe. A configuration of three sensors per pipe allows for the median select approach for NSSS control purposes. The RTDs themselves can be made to fit in the thermowells, but otherwise the device is commercially available. 4.9.3.2 Location The location of these RTDs is underneath the bioshield, on the upstream side of the FWIVs, and downstream of the feedwater separation flange. There will be three RTDs on each feedwater inlet pipe. ((

                                                                                    }}2(a)(c),ECI 4.9.3.3 Installation The RTDs are installed in thermowells in the FW pipe section above the reactor pool level and under-the-bioshield. Conventional installation processes can be adapted for the location.

4.9.3.4 Maintenance The temperature elements are mounted and cables are routed such that maintenance can be performed. The RTDs are accessible and retrievable for necessary maintenance or replacement. The sensors and associated cabling have the ability to be retracted, relocated, or removed during refueling, and the ability to be reinstalled when refueling is complete. The calibration methodology for these RTDs ((

                                                         }}2(a)(b) 4.9.3.5 Qualification The feedwater temperature RTDs, although not safety-related, will be designed to operate in the normal under-the-bioshield environment. The RTDs are developed and will be tested to environmental parameters that envelope this environment. These RTDs are expected to be commercially available with tailoring for fit.

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 4.9.4 Future Work

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                                                             }}2(a)(b) 4.10     Decay Heat Removal System Outlet Temperature 4.10.1 Sensor Functions The primary purpose of the DHRS outlet temperature sensors is to monitor DHRS temperature for indication in the MCR and for PAM Type D variable indication.

DHRS temperature measurement functions:

PAM Type D variable
MCR indication
plant historian 4.10.2 Sensor Requirements Safety classification: B2 Seismic classification: Category I Range: 40 to 440 degrees Fahrenheit Sensor accuracy: +/- (( }}2(a)(c) degrees Fahrenheit Sensor response time: < 6 seconds Quantity: Four (two RTDs per DHRS condenser) 4.10.3 Baseline Concept 4.10.3.1 Summary The baseline concept for the measurement of DHRS outlet temperature is with RTDs in thermowells. Because the locations of the devices are outside of containment, the use of conventional temperature measurement is desired. The DHRS condenser will have

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 thermowells to accommodate the RTD/thermowell approach to measurement. The RTDs must be waterproof and submergible to work in the submerged DHRS condenser. The RTDs can be made to fit in the thermowells. Because of the PAM function, they must be qualified to the environment in which they are located. In certain DBE scenarios, when feedwater is isolated, the DHRS outlet RTDs give indication of steam generator inlet temperature. 4.10.3.2 Location There will be two RTD sensors per DHRS condenser, one per division on each DHRS condenser to support the PAM Type D variable function. These RTDs are located in the bottom piping of the DHRS condenser. 4.10.3.3 Installation The RTDs are installed in thermowells in the lower condenser section outside of containment, in the pool. Conventional installation processes can be adapted for the location. 4.10.3.4 Maintenance The temperature elements are mounted and cables are routed such that maintenance can be performed. The RTDs must be accessible and retrievable for necessary maintenance or replacement during a refueling outage. The sensors and associated cabling have the ability to be retracted, relocated, or removed during refueling, and the ability to be reinstalled when refueling is complete. The calibration methodology for these RTDs ((

                                                             }}2(a)(b) 4.10.3.5           Qualification The PAM function of the DHRS outlet temperature requires that the RTDs be qualified to operate in the pool environment. These RTDs are expected to be commercially available with tailoring for fit.

4.10.4 Future Work

1. ((

                                                           }}2(a)(b)

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 4.11 Under-the-Bioshield Temperature 4.11.1 Sensor Functions The primary function of the under-the-bioshield temperature sensors is to acquire temperature measurements for the associated reactor trip, containment isolation, and DHRS actuation. These sensors also provide temperature indication as a PAM Type D variable and provide indication to the MCR. Under-the-bioshield temperature functions:

reactor trip - high under-the-bioshield temperature
ESFAS - containment isolation - high under-the-bioshield temperature
ESFAS - decay heat removal actuation - high under-the-bioshield temperature
PAM Type D variable
MCR indication
plant historian 4.11.2 Sensor Requirements Safety classification: A1 Seismic classification: Category I Range: 40 to 700 degrees Fahrenheit Sensor accuracy: +/- (( }}2(a)(c) degrees Fahrenheit Sensor response time: 6 seconds Quantity: Four (one for each separation group) 4.11.3 Baseline Concept 4.11.3.1 Summary The baseline concept for the under-the-bioshield temperature measurement is to use harsh environment qualified RTDs mounted underneath the bioshield. These RTDs do not need a thermowell as they are mounted in the environment in which they are sensing. The RTDs may be the same quality RTDs being used for safety system actuations inside containment as the qualification profiles are similar. The four sensing elements are routed to separation groups A, B, C, and D, in the MPS for under-the-bioshield environment based actuation.

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 4.11.3.2 Location The location of the RTDs is outside of containment, underneath the bioshield, on the reactor pool wall. 4.11.3.3 Installation The RTDs are mounted on the reactor pool wall underneath the bioshield. Cabling from the RTDs is routed to the disconnect panel on the pool wall. Conventional installation processes can be adapted for the location. 4.11.3.4 Maintenance The temperature elements are mounted and cables are routed such that maintenance can be performed. The RTDs are accessible and retrievable for maintenance or replacement. The calibration methodology for these RTDs ((

                                                 }}2(a)(b) 4.11.3.5           Qualification The ((
                                                                                  }}2(a)(c) 4.11.4 Future Work

1. ((

                                                       }}2(a)(b)

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 5.0 Pressure Measurement in the NPM NuScale initiated a Phase I pressure study whose purpose was to develop conceptual designs for pressure measurement that meet the requirements of the NPM. The scope of the study was to investigate and develop approaches for measuring the following:

1. Pressurizer pressure

2. Wide range RCS pressure

3. Narrow range containment pressure

4. Wide range containment pressure

5. MS pressure

6. Feedwater/DHRS outlet pressure

Background

A Phase I contract was issued to Ultra Electronics to develop and present conceptual designs for pressure measurement that meet the requirements of the NPM. The pressure-sensing instrumentation ranges are shown in Table 5-1. Inside Containment Pressure Sensors Several concepts for practical approaches to measuring pressure in the NPM were presented in the Phase 1 study that used readily available technologies and products. The inside containment options ((

                                                         }}2(a)(c),ECI

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 ((

              }}2(a)(c),ECI inside containment radiation hardened and temperature tolerant pressure transducer with remote electronics approach for in pressure sensors located in containment.

The development of the inside containment pressure transducer has two approaches, one with remote analog electronics and one with remote digital processing electronics. This sensor equipment diversity is required to meet the equipment diversity assumptions of the NuScale diversity and defense in depth analysis for the MPS. Outside Containment Pressure Sensors The pressure sensors located outside of containment, MS pressure and feedwater pressure, use conventional transmitter technology combined with a re-qualification of the transmitters to envelope the current environment for the respective areas. Alternate pressure measuring approaches as described in section 2.5, were evaluated, and not chosen. These technologies remain as back-ups for the current baseline design. Table 5-1 Pressure Sensor List Pressure Range Safety/Risk Quantity Function Location Sensors (psia) Classification Pressurizer 1500 to 4 RTS/ESFAS Near top of A1 pressure 2200 NSSS control PZR in CNV MCR indication Plant historian Wide range 0 to 2500 4 LTOP Near top of A2 RCS pressure PAM Type B/C/D PZR in CNV Core cooling indication NSSS control MCR indication Plant historian Narrow range 0 to 20 4 RTS/ESFAS Upper part of A1 containment CNV NSSS control pressure RCS leak detect MCR indication Plant historian © Copyright 2018 by NuScale Power, LLC 40

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 Pressure Range Safety/Risk Quantity Function Location Sensors (psia) Classification Wide range 0 to 1200 2 PAM Type B/C/D Upper part of B2 containment Core cooling CNV pressure indication MCR indication Plant historian Main steam 0 to 1200 8 RTS/ESFAS Upstream of A1 pressure (DHR PAM Type D MSIVs on inlet pressure) DHRS tee Steam superheat MCR indication NSSS control Plant historian Input to calorimetric calculation Feedwater 0 to 1200 6 PAM Type D Bottom of B2 pressure/DHRS MCR indication DHRS unit outlet pressure Plant historian NSSS control Input to calorimetric calculation 5.1 Pressurizer Pressure 5.1.1 Sensor Functions Pressurizer pressure signals are used to monitor RCS pressure and to generate appropriate indications, alarms, reactor trips, or ESFAS actuation functions when required. Isolated output signals are also provided for non-safety pressurizer pressure control functions. Pressurizer pressure functions:

reactor trip - high pressurizer pressure
reactor trip - low pressurizer pressure
reactor trip - low-low pressurizer pressure
ESFAS - DHRS actuation - high pressurizer pressure
ESFAS - DHRS - low pressurizer pressure
ESFAS - DHRS - low-low pressurizer pressure
ESFAS - chemical and volume control system (CVCS) isolation - low pressurizer pressure

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1

ESFAS - chemical and volume control system (CVCS) isolation - low-low pressurizer pressure
NSSS control
MCR indication
plant historian 5.1.2 Sensor Requirements Safety classification: A1 Seismic classification: Category I Range: 1500 to 2200 pounds per square inch absolute (psia)

Sensor accuracy: +/- (( }}2(a)(c) percent of calibrated span Sensor Response time: < 0.4 seconds Quantity: Four (one for each separation group) 5.1.3 Baseline Concept The pressure transducer with remote electronics, which is described in section 5.0, was selected for the baseline pressurizer pressure sensor. The primary reason for this choice was its increased temperature and radiation survivability compared to conventional pressure transmitters. This sensor concept has the radiation and temperature tolerant transducer in containment with the conditioning/processing electronics located in a milder environment outside containment. Four pressure transducers are located in containment and sense the pressure in the pressurizer through sensing lines. The transducers convert the pressure signal to an electronic signal. The electronic signal passes through the containment EPAs to be processed by remote digital electronics outside containment. 5.1.3.1 Location The pressurizer pressure transducer is located close to its sensing line taps near the top of the pressurizer section of the RPV. The remote processing electronics are located in a mild environment outside containment. 5.1.3.2 Installation The pressure-sensing taps open to sensing lines that connect to the pressure transducer. The pressure transducer is installed on a mounting in the containment annulus. These sensing lines are designed in accordance with Reference 9.1.1. The transduced signal is routed out of containment using MI cable and through the © Copyright 2018 by NuScale Power, LLC 42

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 containment penetrations. From there, the signal goes to the processing electronics cabinets located in a mild environment. 5.1.3.3 Maintenance During refueling outages, the transducer and the associated electronics can be accessed for calibration and possible replacement. The power supplies are housed in the processing cabinets in a mild environment, and some routine power supply maintenance is expected. 5.1.3.4 Qualification NuScale environmental requirements are the prevailing criteria for sensor qualification. The transducer and the corresponding remote electronics are specified to meet the requirements of the harsh environment qualification standards for the appropriate NuScale environments. 5.1.4 Future Work

1. ((

                                          }}2(a)(b) 5.2      Wide Range Reactor Coolant System Pressure 5.2.1    Sensor Functions The primary function of the wide range RCS pressure measurement is to provide pressure indication for PAM and LTOP.

Wide range RCS pressure functions:

PAM Type B, C, and D variables
degrees of subcooling calculation (PAM Type B variable)
LTOP (with wide range RCS hot temperature)
core cooling indication
NSSS controls

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1

MCR indication
plant historian 5.2.2 Sensor Requirements Safety classification: A2 Seismic classification: Category I Range: 0 to 2500 psia Sensor accuracy: +/- (( }}2(a)(c) percent of calibrated span Sensor response time: < 0.4 seconds Quantity: Four (one for each separation group) 5.2.3 Baseline Concept 5.2.3.1 Summary The pressure transducer with remote electronics, which is described in section 5.0, was selected for the baseline wide range RCS pressure sensor. The primary reason for this choice was its increased temperature and radiation survivability compared to conventional pressure transmitters. This sensor concept has the radiation and temperature tolerant transducer in containment with the conditioning/processing electronics located in a milder environment outside containment.

Four pressure transducers are located in containment and sense the pressure in the RPV through sensing lines. The transducers convert the pressure signal to an electronic signal. The electronic signal passes through the containment EPAs to be processed by remote digital electronics outside containment and provide a signal to the MPS. 5.2.3.2 Location The wide range RCS pressure transducers are located close to the narrow range pressure transducers at the top of the pressurizer section of the RPV. The remote processing electronics are located in a mild environment outside containment. 5.2.3.3 Installation The pressure transducer is installed on a mounting in containment and will measure RCS pressure using sensing lines. These sensing lines are designed in accordance with Reference 9.1.1. The transduced signal is routed using MI cable through the containment penetrations, out of containment to the conditioning/processing electronics. © Copyright 2018 by NuScale Power, LLC 44

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 5.2.3.4 Maintenance During refueling outages, the transducer and the associated electronics can be accessed for calibration and possible replacement. The power supplies are housed in the processing cabinets in a mild environment, and some routine power supply maintenance is expected. 5.2.3.5 Qualification NuScale environmental requirements are the prevailing criteria for sensor qualification. The transducer and the corresponding remote electronics are specified to meet the requirements of the harsh environment qualification standards for the appropriate NuScale environments. 5.2.4 Future Work See Section 5.1.4 for the Future Work items associated with this sensor function. 5.3 Narrow Range Containment Pressure 5.3.1 Sensor Functions The primary function of the narrow range containment pressure sensor is to provide an accurate measurement of containment pressure to supply the high containment pressure reactor trip and ESFAS actuations. The narrow range containment pressure is scaled to measure in a narrow band around expected operating pressures with margin. Narrow range containment pressure is also used to supply main control room alarms, control room displays, and plant historian. Narrow range containment pressure functions:

reactor trip - high containment pressure
ESFAS - containment isolation - high containment pressure
ESFAS - DHRS actuation - high containment pressure
ESFAS - CVCS isolation - high containment pressure
MCR indication
NSSS control
plant historian 5.3.2 Sensor Requirements Safety classification: A1 Seismic classification: Category I

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 Range: 0 to 20 psia Sensor accuracy: +/- (( }}2(a)(c) percent of calibrated span Sensor response time: < 0.4 seconds Quantity: Four, (one for each separation group) 5.3.3 Baseline Concept 5.3.3.1 Summary The pressure transducer with remote electronics, which is described in section 5.0, was selected for the baseline narrow range containment pressure sensor. The primary reason for this choice was its increased temperature and radiation survivability compared to conventional pressure transmitters. This sensor concept has the radiation and temperature tolerant transducer in containment with the conditioning/processing electronics located in a milder environment outside containment. Four pressure transducers are located in containment that sense the pressure in the environment in which they are located. This sensing concept calls for a transducer that is located inside containment near the top of containment. The transducers sense the pressure and convert the pressure signal to an electronic signal. The electronic signal passes through the containment EPAs to be processed by remote electronics outside containment and provide a signal to the MPS. This sensor configuration differs slightly from the other pressure transducers with remote electronics in that it is processing an analog signal instead of a digital signal. The use of analog equipment was specified for this sensor function to provide equipment diversity commensurate with the assumptions in the NuScale diversity and defense in depth analysis for the MPS. 5.3.3.2 Location The narrow range pressure transducers are located inside containment, near the top of containment. This location is chosen for reducing cable length and ease of access and mounting. The remote processing electronics are located in a mild environment outside containment. 5.3.3.3 Installation Four narrow range pressure transducers, one for each separation group, are installed in containment in four different locations, supplying four different separation groups. Each pressure transducer senses the pressure environment in which it is located. The transducers are located in a place that allows them to be maintained and replaced during refueling outages. The pressure signal is routed on MI cables, through the containment penetration and to the analog sensor processing electronics, and then to the MPS system. © Copyright 2018 by NuScale Power, LLC 46

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 5.3.3.4 Maintenance During refueling outages, the transducers can be accessed for calibration and possible replacement. The power supplies for the sensor are housed in processing cabinets. Some routine power supply maintenance is expected. 5.3.3.5 Qualification NuScale environmental requirements are the prevailing criteria for sensor qualification. The transducer and the corresponding remote electronics are specified to meet the requirements of the environment qualification standards for the appropriate NuScale environments. 5.3.4 Future Work

1. ((

                                                                                     }}2(a)(b) 5.4      Wide Range Containment Pressure 5.4.1    Sensor Functions The primary function of the wide range containment pressure measurement is to provide pressure measurement for post-accident monitoring. Wide range containment pressure is also used to supply main control room alarms, control room displays, and plant historian.

Wide range containment pressure functions:

PAM Type B, C, and D variables
core cooling indication
MCR indication
plant historian 5.4.2 Sensor Requirements Safety classification: B2 Seismic classification: Category I Range: 0 to 1200 psia Sensor accuracy: +/- (( }}2(a)(c) percent of calibrated span

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 Sensor response time: < 0.4 seconds Quantity: Two, (one for each division, routed to separation groups B and C) 5.4.3 Baseline Concept 5.4.3.1 Summary The pressure transducer with remote electronics, which is described in section 5.0, was selected for the baseline wide range containment pressure sensor. The primary reason for this choice was its increased temperature and radiation survivability compared to conventional pressure transmitters. This sensor concept has the radiation and temperature tolerant transducer in containment with the conditioning/processing electronics located in a milder environment outside containment. This sensing concept calls for two transducers located inside, near the top of containment. These transducers sense the pressure in the environment that they are in and convert the pressure signal to an electronic signal. The electronic signal passes through the containment EPAs to be processed by remote digital electronics outside containment and provide a 4 to 20 mA signal to the MPS. 5.4.3.2 Location The wide range containment pressure transducers are located inside containment, near the top of containment. This location is chosen for reducing cable length and ease of access and mounting. The processing electronics are located in a mild environment outside of containment. 5.4.3.3 Installation Two wide range pressure transducers are installed in containment in two locations and routed through separation groups B and C penetration assemblies. Each pressure transducer senses the pressure environment in containment. The transmitters are located in a place that allows them to be maintained and replaced during refueling outages. The pressure signal is routed on MI cables, through the containment penetrations, to the sensor processing electronics, and then to the MPS system for processing. 5.4.3.4 Maintenance During refueling outages, the transducers can be accessed for calibration and possible replacement. The power supplies for the sensor are housed in processing cabinets. Some routine power supply maintenance is expected. 5.4.3.5 Qualification NuScale environmental requirements are the prevailing criteria for sensor qualification. The transducer and the corresponding remote electronics are specified to meet the requirements of the harsh environment qualification standards for the appropriate © Copyright 2018 by NuScale Power, LLC 48

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 NuScale environments. Because this pressure sensor has a PAM Type B and C variable function, its qualification requirement includes both normal and DBE containment environments. 5.4.4 Future Work See Section 5.3.4 for the Future Work items associated with this sensor function. 5.5 Main Steam Pressure 5.5.1 Sensor Functions The primary function of the main steam (MS) pressure sensor is to measure main steam pressure as close to the SG steam plenum as possible with the intent of attaining a highly accurate steam pressure measurement for protection system purposes. This measurement is used for RTS/ESFAS actuations, PAM Type D variable function, as well as the superheat calculation, NSSS controls, and MCR indication. Note: MS pressure also serves as DHRS inlet pressure, when DHRS valves are actuated. MS pressure functions:

reactor trip - high steam superheat (with MS temperature)
reactor trip - low steam superheat (with MS temperature)
reactor trip - low MS pressure
reactor trip - low-low MS pressure
reactor trip - high MS pressure
ESFAS - DHRS actuation - high steam superheat (with MS temperature)
ESFAS - DHRS actuation - low steam superheat (with MS temperature)
ESFAS - DHRS actuation - high MS pressure
ESFAS - DHRS actuation - low MS pressure
ESFAS - DHRS actuation - low-low MS pressure
steam superheat calculation
input to secondary side calorimetric calculation
PAM Type D variable (as DHRS inlet pressure)
MCR indication
plant historian 5.5.2 Sensor Requirements Safety classification: A1

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 Seismic classification: Category I Range: 0 to 1200 psia Sensor accuracy: +/- (( }}2(a)(c) percent of calibrated span Sensor response time: < 0.5 seconds Quantity: Eight (four for each MS pipe, two MS pipes) 5.5.3 Baseline Concept 5.5.3.1 Summary The MS pressure sensors will use existing technology and conventional nuclear steam pressure transmitters. Numerous vendors manufacture qualified steam pressure transmitters for nuclear plant MS measurement. The under-the-bioshield temperature environment that these sensors can encounter requires a requalification of the conventional pressure transmitter. If the current conventional transmitter design does not support the qualification profile, then other options such as longer sensing lines to route the transmitter out from underneath the bioshield, special shielding, or installation of a pressure transducer with remote electronics will be considered. 5.5.3.2 Location The location of the MS pressure transmitter sensing lines is on the MS pipes, upstream of the MSIVs on the DHRS tee piping. The sensing lines are upstream of the MSIV to measure the pressure closest to the SG plenum as possible, but outside of containment and above the reactor pool water. The pressure taps for the sensing lines are on the DHRS piping that splits off from the MS fitting. There are two pressure taps off of each DHRS pipe connecting to separate sensing lines. The sensing lines connect to transmitters that are located in an accessible position. There are eight transmitters total. There are four separation groups of transmitters for each MS pipe. 5.5.3.3 Installation The installation of MS pressure transmitters is straightforward, as the piping that the sensing lines tap into is outside of containment and above the reactor pool water level. These sensing lines are designed in accordance with Reference 9.1.1. 5.5.3.4 Maintenance Routine maintenance of the MS pressure transmitters consists of post cycle transmitter calibrations and visual inspections, so the transmitters must be accessible for this maintenance. © Copyright 2018 by NuScale Power, LLC 50

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 5.5.3.5 Qualification Due to the high temperature underneath the bioshield for DBE conditions, the currently available transmitters require requalification. If the current conventional transmitter design does not support the qualification profile, then other options such as longer sensing lines to route the transmitter out from underneath the bioshield, special shielding, or installation of a pressure transducer with remote electronics will be considered. 5.5.4 Future Work

1. ((

          }}2(a)(b) 5.6      Feedwater Pressure/Decay Heat Removal System Outlet Pressure 5.6.1    Sensor Functions There are no valves between the feedwater plenum of the SG and the DHR condenser in the area near the bottom of the DHRS condenser. Therefore, one pressure instrument is used to measure both functions. This instrument performs its feedwater pressure function when the DHRS valves (at the inlet to the DHRS heat exchanger) are closed, and performing its DHRS outlet pressure function when the DHRS valves are open (indicating the DHRS unit is active and MS and feedwater are isolated).

DHRS outlet pressure functions:

input to secondary side calorimetric calculation
PAM Type D variable
MCR indication
plant historian Feedwater pressure functions:
NSSS control
input to secondary side calorimetric calculation
MCR indication
plant historian

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 All of the above functions apply to the one instrument for the purpose of designing and qualifying the sensor. 5.6.2 Sensor Requirements Safety classification: B2 Seismic classification: Category I Range: 0 to 1200 psia Sensor accuracy: +/-(( }}2(a)(c) percent of calibrated span Sensor response time: < 0.5 seconds Quantity: Six (three per DHRS condenser) 5.6.3 Baseline Concept 5.6.3.1 Summary The baseline concept for the measurement of feedwater pressure/DHRS outlet pressure is a conventional pressure measurement device. Because the location of the device is outside of containment, conventional means of pressure measurement is desired. The basic concept is to have three transmitters per DHRS condenser for a total of six separate pressure transmitters. These transmitters are waterproof for installation in the reactor pool on the DHRS condenser. 5.6.3.2 Location The feedwater pressure/DHRS outlet pressure transmitters are located in the reactor pool at the bottom of the DHRS condenser. 5.6.3.3 Installation The transmitters are located in the reactor pool and mounted to part of the DHRS condenser structure. This allows them to be in close proximity to their respective sensing lines. These sensing lines are designed in accordance with Reference 9.1.1. The signal cable is waterproof cable that routes the signal from the transmitter to the electrical panel near the platform above the vessel. From there the signal goes to the MPS cabinets. 5.6.3.4 Maintenance The feedwater pressure/DHRS outlet pressure sensors are mounted and cables are routed such that maintenance can be performed while the instrument is in the refueling bay dry dock during refueling outages. As the instruments are on the outside of the containment vessel, they are accessible for maintenance calibrations, and replacements. © Copyright 2018 by NuScale Power, LLC 52

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 Calibration of these transmitters is similar to conventional pressure transmitter calibrations. 5.6.3.5 Qualification The DHRS pressure sensors perform a PAM Type D variable function. Sensors are specified to be conservatively qualified to operate in the reactor pool environment for any environment that requires DHRS actuation. 5.6.4 Future Work

1. ((

                                                                    }}2(a)(b)

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 6.0 Reactor Coolant System Flow In 2014, NuScale initiated a Phase I ((

                                                                          }}2(a)(c)(d) for use in the NuScale design as an RCS flowmeter. The Phase 1 study had five objectives as follows:
        *    ((
                                       }}2(a)(b)

Because the Phase 1 study yielded positive results, a Phase 2 project was initiated ((

                                                                                }}2(a)(b) The objectives of the Phase 2 project are:
        *    ((
                       }}2(a)(b) and therefore was chosen as the baseline measurement approach.

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 Table 6-1 RCS Flowmeter Safety/Risk Sensor Range Quantity Function Location Classification Reactor 0 to 4 RTS Trip/CVCS isolation In the lower A1 coolant 110% Low-low RCS flow section of system flow ESFAS-demineralized containment water system isolation below the steam Low RCS flow generator section of the MCR indication RPV Input to calorimetric calculations NSSS control Plant historian PAM Type D 6.1 Reactor Coolant System Flowmeter 6.1.1 Sensor Functions The primary function of the reactor coolant flowmeter is to provide indication of RCS flow for MCR display and to provide reactor trip and ESFAS actions on low RCS flow and low-low RCS flow. Four channels of reactor coolant flow signals are required for the RTS and ESFAS functions, and these flow signals are passed to MCS for control functions, alarms, displays, and plant historian. RCS flow measurement functions:

reactor trip - low-low RCS flow
ESFAS - CVCS isolation - low-low RCS flow
ESFAS - demineralized water system isolation - low RCS flow
NSSS Control
PAM Type D variable
input to primary side calorimetric calculation
MCR indication
plant historian 6.1.2 Sensor Requirements Safety classification: A1 Seismic classification: Category I

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 Range: 0 to 110 percent of full power flow Sensor accuracy: ((

                                                        }}2(a)(c)

Sensor response time: 1.0 second Quantity: Four (one for each separation group) 6.1.3 Baseline Concept 6.1.3.1 Summary The preferred option for RCS flow measurement is the ((

                      }}2(a)(c)(d) with modification for the NuScale design. This device uses four pairs of ultrasonic transducers with each pair mounted on a nozzle. The four nozzles are mounted in four vessel quadrants on the reactor vessel outer shell below the steam generators and ((
                                                                              }}2(a)(c),ECI 6.1.3.2 Location The ((
                                                                  }}2(a)(c),ECI They are in the proximity of the RCS cold temperature RTDs. This location was chosen to give a straight annulus for the reflection of the signal, and also to maximize the turbulent flow for a more homogenous flow profile.

6.1.3.3 Installation The baseline reactor coolant flowmeter concept requires the mounting of ((

                                                                                                        }}2(a)(c),ECI

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 ((

                         }}2(a)(c),ECI 6.1.3.4 Maintenance To ensure accessibility of the transducers for maintenance and replacement, the transducers are located in the lower downcomer region that is exposed when the upper reactor module is separated for refueling. The transducers can be removed and replaced, using access to the side of the vessel, should that be necessary.

Based on ((

        }}2(a)(c),ECI routine maintenance of the transducer during or between cycles is not generally required. However, the electronics cabinet, which is located in a mild environment and readily accessible, may require periodic maintenance during refueling outages.

6.1.3.5 Qualification Although the technology of this device is mature and currently commercially available for feedwater flow measurement applications, the harsh environment qualification of this device for the NuScale application is a new application of the existing product. The transducer itself will need to be qualified to CNV normal and DBE conditions. The possibility of submergence in an accident condition and during refueling requires the transducer to be water proof and submergible. This flowmeter is specified to meet the requirements of the applicable industry standards, both for the transducers and for the remote electronics processing units. 6.1.4 Future Work

1. ((

                                                                                }}2(a)(b)

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 7.0 Level Measurement in the NPM The initial approach for the RPV riser level measurement was to use a differential pressure transducer that required a reference leg located in containment. This approach had several engineering constraints, one of which was the need for a reference leg that would have to be separated during refueling operations. Other constraints that existed with the differential pressure method were reference leg temperature compensation, condensate pot cooling during a DBA environment, and the availability of a delta-pressure cell that could survive and operate in the containment environment. The Phase 1 study looked for methods that would measure containment water level, pressurizer level, and RPV riser water level. ((

                                                                               }}2(a)(c) models indicate that lengths to accommodate the NuScale application are achievable. NuScale plans to conduct tests to select the appropriate method and vendor for the development of level sensing devices for the NuScale design.

There are three NPM related level measurements. The first two, pressurizer level/RPV riser level and containment water level, are baselined as (( }}2(a)(c) technology sensors. The third measurement, DHRS level, is baselined as a level switch technology and is located on the DHRS piping. © Copyright 2018 by NuScale Power, LLC 58

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 Table 7-1 Pressurizer/RPV/CNV Water Level Level Safety/Risk Range Quantity Function Location Transmitters Classification Pressurizer 0 to 100% 4 RTS/ESFAS Top of RPV A1 level/RPV riser (PZR level PAM Type B, C, to upper level span is 130.1 and D variables core plate inches) Core cooling (RPV riser indication level span is NSSS control estimated at MCR indication 554.9 inches) Plant historian Containment 0 to 100% 4 ESFAS - ECCS Top of A1 water level actuation containment (containment to below the level span is ESFAS L-1 reactor estimated at interlock recirculation 683.5 inches) PAM Type B, C, valves and D MCR indication NSSS control Plant historian DHRS level N/A 8 MCR indication On DHRS B2 switch piping (discrete) Plant historian 7.1 Pressurizer Level and Reactor Pressure Vessel Riser Level 7.1.1 Sensor Functions The primary function of the pressurizer level/RPV riser level sensor is to provide inputs to the reactor trip and ESFAS actuations for safety system purposes. It is intended to indicate an increase or a decrease in RCS inventory, both of which have module protection implications. It also provides the necessary control room alarms and indications. In its NSSS control function, pressurizer level is maintained within an operating band by the CVCS makeup and the letdown functions. The pressurizer level/RPV riser level functions are implemented in a separate safety function module within each separation group. The level indications are also isolated to perform their control functions. The pressurizer level/RPV riser level functions are listed below. Pressurizer level measurement functions:

reactor trip - high pressurizer level

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1

reactor trip - low pressurizer level
ESFAS - containment isolation - low-low pressurizer level
ESFAS - DHRS actuation - low-low pressurizer level
ESFAS - CVCS isolation - high and low-low pressurizer level
ESFAS - pressurizer heater isolation - low pressurizer level
core cooling indication
NSSS controls
MCR indication
plant historian RPV Riser Level Measurement Functions:
ESFAS - ECCS actuation - low RPV riser level
PAM Type B, C, and D variables
core cooling Indication
MCR indication
plant historian 7.1.2 Sensor Requirements Safety classification: A1 Seismic classification: Category I Range: 0 percent to 100 percent calibrated span (The span for the pressurizer level is 130.1 inches, and the span for the RPV riser level is estimated at 554.9 inches)

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 7.1.3 Baseline Concept 7.1.3.1 Summary ((

                                                                                           }}2(a)(c),ECI The NuScale diversity and defense-in-depth analysis for the MPS specifies that different design organizations are required for equipment diversity in defense of common-cause failure (CCF) for the level measurement. Diversity can be assessed using six different attributes: design diversity, equipment diversity, functional diversity, human diversity, signal diversity, and software diversity. The intent of the sensor design and development project is to locate two or more vendors with different designs to ensure that as many of these attributes as possible can be satisfied.

7.1.3.2 Location The ((

                                                                     }}2(c)ECI ((
                                                              }}2(c) 7.1.3.3 Installation

((

                                                                                                  }}2(a)(c)ECI

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 ((

                                                        }}2(a)(c)ECI 7.1.3.4 Maintenance Sensor calibration and maintenance are conducted at the processing electronics cabinet during a refueling outage. The sensor assembly should not need to be accessed for calibration activities. The development of this calibration methodology is itemized in the Future Work section below.

7.1.3.5 Qualification Qualification of ((

                                                 }}2(a)(c)

((

                                      }}2(a)(b) sensor meets the specified qualification requirements.

7.1.4 Future Work

1. ((

                                                                   }}2(a)(b) 7.2      Containment Water Level 7.2.1    Sensor Functions The primary function of the containment water level sensors is to provide a signal to allow an ESFAS actuation for safety system purposes. It is intended to protect the core by activating the emergency core cooling system (ECCS) to allow recirculation of RCS water inventory in containment and into the RPV. It also provides the necessary control room alarms/indications, and inputs to NSSS controls.

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 Containment water level measurement functions:

ESFAS - ECCS actuation - high CNV water level
ESFAS - L-1 interlock
PAM Type B, C, and D variables
core cooling indication
MCR indication
NSSS controls (containment flooding/containment evacuation)
plant historian 7.2.2 Sensor Requirements Safety classification: A1 Seismic classification: Category I Range: 0 to 100 percent calibrated span The containment level span is estimated at 683.5 inches Sensor accuracy: +/- (( }}2(a)(c) percent of calibrated span Sensor response time: < 2 seconds Quantity: Four (one for each separation group) 7.2.3 Baseline Concept 7.2.3.1 Summary

((

                          }}2(a)(c),ECI

((

                                                                         }}2(a)(c)

The NuScale diversity and defense-in-depth analysis for the MPS specifies that different design organizations are required for equipment diversity in defense of CCF for the level measurement. Diversity can be assessed using six different attributes: design diversity, equipment diversity, functional diversity, human diversity, signal diversity, and software diversity. The intent of the sensor design and development project is to locate two or more vendors with different designs to ensure that as many of these attributes as possible can be satisfied. © Copyright 2018 by NuScale Power, LLC 63

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 7.2.3.2 Location ((

                                          }}2(a)(c) 7.2.3.3 Installation

((

                                                 }}2(a)(c)ECI 7.2.3.4 Maintenance Sensor calibration is conducted at the processing electronics cabinet during a refueling outage. The sensor assembly should not need to be accessed for calibration activities.

The development of this calibration methodology and periodic maintenance is itemized in the Future Work section. 7.2.3.5 Qualification See Section 7.1.3.5 for information regarding the level sensor qualification. 7.2.4 Future Work See Section 7.1.4 for Future Work items for this sensor function. 7.3 Decay Heat Removal System Level 7.3.1 Sensor Functions The primary function of the DHRS heat exchanger level measurement is to provide DHRS binary (yes/no) indication of water level up to a certain height in the DHRS piping for control room indication. This liquid level acts as an indication of the operability of a train of DHRS with respect to determining an operable level of condensable gases. DHRS level measurement functions:

MCR indication

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1

plant historian 7.3.2 Sensor Requirements Safety classification: B2 Seismic classification: Category II Range: N/A Sensor accuracy: N/A Sensor response time: N/A Quantity: Eight, (four level switches per each DHRS unit) 7.3.3 Baseline Concept 7.3.3.1 Summary The baseline concept for the DHRS level sensors is to use a level switch approach. The location for this sensor outside containment allows for accessible installation and access to the pipe for the inclusion of a level switch. Several manufacturers offer level switches that would function adequately for this application.

7.3.3.2 Location The DHRS level switch is mounted on the DHRS pipe, near the outside top of containment, which runs to the DHRS heat exchanger. 7.3.3.3 Installation The sensor taps are fitted into the DHRS steam piping. The switch inserts into the pipe taps and sends the signal electronically to the disconnect panel on MI cable or cable of similar nature that is waterproof. From the disconnect panel, the signals are fed to the MCS for MCR indication. 7.3.3.4 Maintenance The level switch is located so that it is accessible for maintenance and periodic calibration. 7.3.3.5 Qualification This level switch will be designed to operate in the reactor pool and is attached to the DHRS unit during normal conditions. Because there is no enclosure for the level switch, the switch will be tested for every condition associated with that area of the reactor pool, including submergence. © Copyright 2018 by NuScale Power, LLC 65

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 7.3.4 Future Work

1. ((

                                      }}2(a)(b)

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 8.0 Summary and Conclusions This report addresses the current state of the NuScale NSSS process sensors. It addresses the sensors, functions, sensor requirements, design concepts, sensor locations, installation details, maintenance approaches, and qualification methodology. The report also identifies the areas that need further investigation and study. The normal and post-accident containment operating environments of the NPM are unique when compared to the containment of a conventional pressurized water reactor. The information presented in this report outlines the approach to monitoring the process variables and the future work and investigation that remains to be done. The temperature measurements throughout the NPM utilize existing technology. The RTD was selected in all cases, excluding the ICI instruments, due to its nuclear experience, accuracy, and robust design. The description of how the RTDs are incorporated into the design is captured in Section 4 of this report. The selection of pressure measurement devices had to consider the effects of radiation and temperature on electrical devices located in containment. In the conventional measurement approach, the electronics are housed with the pressure sensor, and as such would not survive in the containment environment. This report covers the selection of the containment pressure transducer with remote electronics as the solution for pressure measurement. The advantage of this transducer configuration is that the electronics are not required to be in close proximity to the sensing element. This solution is being investigated with the intention of improving on existing devices. Measuring RCS flow in the RPV ((

                                                                                               }}2(c)(d),ECI Level measurements in the containment and the RPV were initially going to be measured with a conventional differential pressure method using a condensing chamber and reference leg, but it was realized that the technique would not work in the NPM.

Other solutions were investigated and it became apparent that the technology that showed the most promise was ((

                                      }}2(a)(c)

All signals in containment are transmitted through radiation and temperature tolerant MI cable. ((

                                                                      }}2(a)(c),ECI

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 The future work items associated with each sensor function outline the remaining work to be done in that sensor area. (( }}2(c)(d) Ultra Electronics, are pursuing this work. As the sensor requirements and sensor design become more mature, the details of this sensor definition will be captured in the appropriate drawings and in the respective system design description documents. In addition to providing information about the sensors for inclusion on their respective system design descriptions, this report also serves as the basis for future technical reports on advanced sensors. © Copyright 2018 by NuScale Power, LLC 68

Nuclear Steam Supply System Advanced Sensor Technical Report TR-0316-22048-NP Rev. 1 9.0 References 9.1 Industry and Regulatory Standards 9.1.1 International Society of Automation, ISA-67.02.01-1999 Nuclear Safety-Related Instrument Sensing Line Piping and Tubing Standards for Use in Nuclear Power Plants, Research Triangle Park, N.C. 9.1.2 10 CFR 50.34(f), Additional TMI-related requirements © Copyright 2018 by NuScale Power, LLC 69

LO-0718-61021 : Affidavit of Thomas A. Bergman, AF-0718-61023 NuScale Power, LLC 1100 NE Circle Blvd., Suite 200 Corvallis, Oregon 97330 Office 541.360-0500 Fax 541.207.3928 www.nuscalepower.com

NuScale Power, LLC AFFIDAVIT of Thomas A. Bergman I, Thomas A. Bergman, state as follows: (1) I am the Vice President of Regulatory Affairs of NuScale Power, LLC (NuScale), and as such, I have been specifically delegated the function of reviewing the information described in this Affidavit that NuScale seeks to have withheld from public disclosure, and am authorized to apply for its withholding on behalf of NuScale (2) I am knowledgeable of the criteria and procedures used by NuScale in designating information as a trade secret, privileged, or as confidential commercial or financial information. This request to withhold information from public disclosure is driven by one or more of the following: (a) The information requested to be withheld reveals distinguishing aspects of a process (or component, structure, tool, method, etc.) whose use by NuScale competitors, without a license from NuScale, would constitute a competitive economic disadvantage to NuScale. (b) The information requested to be withheld consists of supporting data, including test data, relative to a process (or component, structure, tool, method, etc.), and the application of the data secures a competitive economic advantage, as described more fully in paragraph 3 of this Affidavit. (c) Use by a competitor of the information requested to be withheld would reduce the competitors expenditure of resources, or improve its competitive position, in the design, manufacture, shipment, installation, assurance of quality, or licensing of a similar product. (d) The information requested to be withheld reveals cost or price information, production capabilities, budget levels, or commercial strategies of NuScale. (e) The information requested to be withheld consists of patentable ideas. (3) Public disclosure of the information sought to be withheld is likely to cause substantial harm to NuScales competitive position and foreclose or reduce the availability of profit-making opportunities. The accompanying report reveals distinguishing aspects about the process and method by which NuScale develops its nuclear steam supply advanced sensors. NuScale has performed significant research and evaluation to develop a basis for this process and method and has invested significant resources, including the expenditure of a considerable sum of money. The precise financial value of the information is difficult to quantify, but it is a key element of the design basis for a NuScale plant and, therefore, has substantial value to NuScale. If the information were disclosed to the public, NuScale's competitors would have access to the information without purchasing the right to use it or having been required to undertake a similar expenditure of resources. Such disclosure would constitute a misappropriation of NuScale's intellectual property, and would deprive NuScale of the opportunity to exercise its competitive advantage to seek an adequate return on its investment. (4) The information sought to be withheld is in the enclosed report entitled Nuclear Steam Supply System Advanced Sensors Technical Report. The enclosure contains the designation Proprietary" at the top of each page containing proprietary information. The information considered by NuScale to be proprietary is identified within double braces, "(( }}" in the document. (5) The basis for proposing that the information be withheld is that NuScale treats the information as a trade secret, privileged, or as confidential commercial or financial information. NuScale relies upon AF-0718-61023 Page 1 of 2

the exemption from disclosure set forth in the Freedom of Information Act ("FOIA"), 5 USC § 552(b)(4), as well as exemptions applicable to the NRC under 10 CFR §§ 2.390(a)(4) and 9.17(a)(4 ). (6) Pursuant to the provIsIons set forth in 10 CFR § 2.390(b)(4), the following is provided for consideration by the Commission in determining whether the information sought to be withheld from public disclosure should be withheld: (a) The information sought to be withheld is owned and has been held in confidence by NuScale. (b) The information is of a sort customarily held in confidence by NuScale and , to the best of my knowledge and belief, consistently has been held in confidence by NuScale. The procedure for approval of external release of such information typically requires review by the staff manager, project manager, chief technology officer or other equivalent authority, or the manager of the cognizant marketing function (or his delegate), for technical content, competitive effect, and determination of the accuracy of the proprietary designation. Disclosures outside NuScale are limited to regulatory bodies , customers and potential customers and their agents , suppliers , licensees , and others with a legitimate need for the information, and then only in accordance with appropriate regulatory provisions or contractual agreements to maintain confidentiality. (c) The information is being transmitted to and received by the NRC in confidence. (d) No public disclosure of the information has been made, and it is not available in public sources. All disclosures to third parties , including any required transmittals to NRC, have been made, or must be made, pursuant to regulatory provisions or contractual agreements that provide for maintenance of the information in confidence. (e) Public disclosure of the information is likely to cause substantial harm to the competitive position of NuScale, taking into account the value of the information to Nu Scale, the amount of effort and money expended by NuScale in developing the information, and the difficulty others would have in acquiring or duplicating the information. The information sought to be withheld is part of NuScale's technology that provides NuScale with a competitive advantage over other firms in the industry. NuScale has invested significant human and financial capital in developing this technology and Nu Scale believes it would be difficult for others to duplicate the technology without access to the information sought to be withheld. I declare under penalty of perjury that the foregoing is true and correct. Executed on October 1, 2018. AF-0718-61023 Page 2 of 2}}

ML18274A392

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