ML18194A648
| ML18194A648 | |
| Person / Time | |
|---|---|
| Site: | NuScale |
| Issue date: | 07/13/2018 |
| From: | Rad Z NuScale |
| To: | Document Control Desk, Office of New Reactors |
| References | |
| L 0-0718-60860 | |
| Download: ML18194A648 (8) | |
Text
.::-*:*.. NU SCALE L 0-0718-60860
.:. .:. POWER' July 13, 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 Changes to Final Safety Analysis Report Section 7.2, System Features, Technical Specifications Section 1.1, Definitions, and the Bases of Technical Specifications Section 3.3, Instrumentation
REFERENCES:
Letter from NuScale Power, LLC to Nuclear Regulatory Commission, "NuScale Power, LLC Submittal of the NuScale Standard Plant Design Certification Application, Revision 1," dated March 15, 2018 (ML18086A090)
During a June 25, 2018 public teleconference with members of the NRC staff, NuScale Power, LLC (NuScale) discussed potential updates to Final Safety Analysis Report (FSAR) and Technical Specifications related to the description of module protection system self-testing features. As a result of this discussion, NuScale made changes to the descriptions in FSAR section 7.2, "System Features,"
Technical Specifications section 1.1, "Definitions," and the Bases of Technical Specifications section 3.3, "Instrumentation."
The Enclosure to this letter provides a mark-up of the affected pages incorporating the revisions in red line/strikeout format. NuScale will include this change as part of a future revision to the NuScale Design Certification Application.
This letter makes no regulatory commitments or revisions to any existing regulatory commitments.
Please feel free to contact Carrie Fosaaen at 541-452-7126 or at cfosaaen@nuscalepower.com if you have any questions.
Sincerely,
~~
ackary W. Rad Director, Regulatory Affairs NuScale Power, LLC Distribution: Samuel Lee, NRC, OWFN-8G9A Gregory Cranston, NRC, OWFN-8G9A Omid Tabatabai, NRC, OWFN-8G9A Getachew Tesfaye, NRC, OWFN-8G9A
Enclosure:
"Changes to NuScale Final Safety Analysis Report Section 7.2, "System Features,"
Technical Specifications Section 1.1, "Definitions," and the Bases of Technical Specifications Section 3.3, "Instrumentation."
NuScale Power, LLC 1100 NE Circle Blvd , Suite 200 Corvallis, Oregon 97330 Office 541.360-0500 Fax 541.207.3928 www.nuscalepower.com
LO-0718-60860
Enclosure:
Changes to NuScale Final Safety Analysis Report Section 7.2, System Features, Technical Specifications Section 1.1, Definitions, and the Bases of Technical Specifications Section 3.3, Instrumentation.
NuScale Power, LLC 1100 NE Circle Blvd., Suite 200 Corvallis, Oregon 97330 Office 541.360-0500 Fax 541.207.3928 www.nuscalepower.com
NuScale Final Safety Analysis Report System Features RAI 07.02.DSRS-4 7.2.8.2 Other Auxiliary Features Other auxiliary features of the MPS that are part of the MPS by association (i.e., not isolated from the MPS) but are not required for the MPS to perform its safety functions include the following:
RAI 07.02.DSRS-4
- 1) Continuous online checkingself-testing and self diagnostics. The continuous online checkingself-testing and self diagnostic functions are described in Section 7.2.15. These functions are designed and qualified as part of the MPS as described in TR-1015-18653-P-A such that the self-checkingtesting and diagnostics functions do not adversely affect the MPS from performing its safety functions.
RAI 07.02.DSRS-4
- 2) Communication from safety-related portions of the MPS to nonsafety-related components. Communication interfaces from safety-related safety function modules, scheduling and bypass modules, scheduling and voting modules, or EIMs to the MIB communications module are provided in order to transmit data to nonsafety-related systems and nonsafety-related displays. Communication interfaces on safety-related safety function modules, scheduling and bypass modules, scheduling and voting modules, and EIMs are designed and qualified as part of the MPS such that the communications do not adversely affect the MPS from performing its safety functions as described in Section 7.1.2.
RAI 07.02.DSRS-4
- 3) Capability for control of safety-related components by using nonsafety-related module control system via the actuation priority logic function within the equipment interface module. These features are designed to not adversely affect the MPS as described in Section 7.1.2 and Section 7.2.3.
RAI 07.02.DSRS-4
- 4) Isolation devices and circuitry. Electrical power for the MPS is supplied by the nonsafety-related highly reliable DC power system (EDSS) as described in Section 8.3 through a Class 1E isolation device that provides isolation between the Class 1E components within the MPS and non-Class 1E components as described in Section 7.1.2. The Class 1E isolation devices are designed and qualified to comply with IEEE Std 603-1991.
RAI 07.02.DSRS-4
- 5) Shunt trip relay/coil circuitry in reactor trip breakers and pressurizer heater breakers. The shunt trip coil and relays of the reactor trip breakers and the pressurizer heater trip breakers do not affect the MPS in accomplishing its safety functions. Each breaker utilizes its own nonsafety-related shunt trip coil and relay as a backup to the safety-related undervoltage coil as described in Section 7.0.4.1.
The shunt trip coil and relay are nonsafety-related diverse means for opening the reactor trip and pressurizer heater trip breakers and are not capable of closing these breakers once opened.
RAI 07.02.DSRS-4 Tier 2 7.2-46 Draft Revision 2
Definitions 1.1 1.0 USE AND APPLICATION 1.1 Definitions
NOTE--------------------------------------------------------------
The defined terms of this section appear in capitalized type and are applicable throughout these Technical Specifications and Bases.
Term Definition ACTIONS ACTIONS shall be that part of a Specification that prescribes Required Actions to be taken under designated Conditions within specified Completion Times.
ACTUATION LOGIC TEST An ACTUATION LOGIC TEST shall be:
- a. The use of diagnostic programsself-testing features, or application of simulated or actual input combinations as appropriate, to test digital computer hardware; and
- b. Verification of the required logic output.
An ACTUATION LOGIC TEST shall include each possible interlock logic state required for OPERABILITY of a logic circuit. The ACTUATION LOGIC TEST shall verify the OPERABILITY of each manual logic input device required for channel OPERABILITY. The ACTUATION LOGIC TEST shall be conducted such that it provides component overlap with the actuated device. The ACTUATION LOGIC TEST may be performed by means of any series of sequential, overlapping, or total steps, and each step must be performed within the Frequency in the Surveillance Frequency Control Program for the devices included in the step.
AXIAL OFFSET (AO) AO shall be the difference in power generated in the top half of the core (Ptop) and the bottom half of the core (Pbottom), divided by the sum of the power generated in the core (Ptotal).
AO = (Ptop - Pbottom) / Ptotal NuScale 1.1-1 Draft Revision 2.0
Module Protection System Instrumentation B 3.3.1 BASES BACKGROUND (continued) used to calculate the NTSPs is provided in the "NuScale Instrument Setpoint Methodology" (Ref. 7). The as-left tolerance and as-found tolerance band methodology is provided in the SP. The as-found OPERABILITY limit for the purpose of the CHANNEL CALIBRATION is defined as the as-left limit plus the acceptable drift about the NTSP.
The NTSPs listed in the SP are based on the methodology described in Reference 7, which incorporates all of the known uncertainties applicable for each channel. The magnitudes of these uncertainties are factored into the determination of each NTSP. All field sensors and signal processing equipment for these channels are assumed to operate within the allowances of these uncertainty magnitudes. Transmitter and signal processing equipment calibration tolerances and drift allowances must be specified in plant calibration procedures, and must be consistent with the values used in the setpoint methodology.
The OPERABILITY of each transmitter or sensor can be evaluated when its as-found calibration data are compared against the as-left data and are shown to be within the setpoint methodology assumptions. The as-left and as-found tolerances listed in the SP define the OPERABILITY limits for a channel during a periodic CHANNEL CALIBRATION that requires trip setpoint verification.
NTSPs, in conjunction with the use of as-found and as-left tolerances, consistent with the requirements of the SP will ensure that SLs of Chapter 2.0, "SAFETY LIMITS (SLs)," are not violated during AOOs, and the consequences of DBAs will be acceptable, providing the unit is operated from within the LCOs at the onset of the AOO or DBA and the equipment functions as designed.
The MPS incorporates continuous system self-testingself checking features from the sensor input to the output switching logic, with the exception of the actuation and priority logic (APL). The self-testingself checking features evaluate whether the MPS is functioning correctly.
Surveillance testing verifies OPERABILITY of the APL. Self-testingSelf checking features include on-line diagnostics for the MPS hardware and communications tests. These self-testsself checking tests do not interfere with normal system operation.
In addition to the self-testingself checking features, the system includes functional testing features. Functional testing of the entire MPS, from SFM input through the opening of individual RTBs and actuation of ESFAS components, can be performed either at power or shutdown. The manual actuation switches in the MCR cannot be tested at power because they NuScale B 3.3.1-6 Draft Revision 2.0
Module Protection System Instrumentation B 3.3.1 BASES APPLICABLE SAFETY ANALYSES, LCO, and APPLICABILITY (continued)
RTS and ESFAS Operating Bypass Interlocks and Permissives Reactor protection permissives and interlocks are provided to ensure reactor trips and ESF actuations are in the correct configuration for the current unit status (Ref. 4). This is to ensure that the protection system functions are not bypassed during unit conditions under which the safety analysis assumes the functions are OPERABLE. Therefore, the permissive and interlock functions do not need to be OPERABLE when the associated reactor trip and ESF functions are outside the applicable MODES. Proper operation of these permissive and interlocks supports OPERABILITY of the associated reactor trip and ESF functions and/or the requirement for actuation logic OPERABILITY. The permissives and interlocks must be in the required state, as appropriate, to support OPERABILITY of the associated functions. The permissives and interlocks associated with each MPS Instrumentation Function channel, each Reactor Trip System (RTS) Logic and Actuation Function division, and each Engineered Safety Features Actuation System (ESFAS) Logic and Actuation Function division, respectively, must be OPERABLE for the associated Function channel or Function division to be OPERABLE. The combination of the continuous self-testingself checking features of the MPS and the CHANNEL CALIBRATION specified by SR 3.3.1.4 verify the OPERABILITY of the interlocks and permissives. The permissives and interlocks are:
Intermediate Range Log Power Permissive, N-1 The Intermediate Range Log Power, N-1 permissive is established when the Intermediate Range Log Power channel increases to approximately one decade above the channel lower range limit. The N-1 permissive performs the following:
- 1. On increasing power, the N-1 permissive allows the manual block of the following:
- High Source Range Count Rate Reactor Trip and Demineralized Water System Isolation actuation; and
- High Source Range Log Power Rate Reactor Trip and Demineralized Water System Isolation actuation.
This prevents the premature block of the High Source Range Count Rate and High Source Range Log Power Rate trips and allows the operator to ensure that the Intermediate Range channel is OPERABLE as power increases prior to leaving the source range.
NuScale B 3.3.1-11 Draft Revision 2.0
RTS Logic and Actuation B 3.3.2 BASES SURVEILLANCE SR 3.3.2.1 REQUIREMENTS An ACTUATION LOGIC TEST on each RTS Logic division is performed to ensure the division will perform its intended function when needed.
These tests verify that the RTS is capable of performing its intended function, from SFM input signals to the SVM through actuation of the RTBs. A Note is provided indicating that the SR does not need to be met for reactor trip breakers that are open. This allowance permits continued operation when a trip breaker may not be able to satisfy the requirements of the ACTUATION LOGIC TEST but is already open. When a reactor trip breaker is open it has performed its safety function.
MPS testing from the input sensors to the SVMs is addressed by surveillance requirements specified in LCO 3.3.1, Module Protection System (MPS) Instrumentation. The RTS logic and actuation circuitry functional testing is accomplished with continuous system self-testingself checking features on the SVMs and EIMs and the communication between them. The self-testingself checking features are designed to perform complete functional testing of all circuits on the SVM and EIM, with the exception of the actuation and priority logic (APL) circuitry. The self checkingself-testing includes testing of the voting and interlock/permissive logic functions. The built-in self-testingself checking will report a failure to the operator and place the SVM or EIM in a fail-safe state.
The only portion of the RTS logic and actuation circuitry that is not self checkedself-tested is the APL. The manual actuation switches, enable nonsafety control switches, and operating bypass switches do not include self checkingself-testing features and their OPERABILITY is verified by required surveillance testing. The manual actuation switches are addressed by surveillance requirements specified in LCO 3.3.4, "Manual Actuation Functions."
This ACTUATION LOGIC TEST includes testing of the APL on all RTS EIMs, the enable nonsafety control switches, and the operating bypass switches. The ACTUATION LOGIC TEST includes a review of any alarms or failures reported by the self-testingself checking features.
The Surveillance Frequency is controlled under the Surveillance Frequency Control Program.
NuScale B 3.3.2-4 Draft Revision 2.0
ESFAS Logic and Actuation B 3.3.3 BASES SURVEILLANCE SR 3.3.3.1 REQUIREMENTS An ACTUATION LOGIC TEST on each ESFAS division is performed to ensure the division will perform its intended function when needed. These tests verify that the ESFAS actuation functions are capable of performing their intended function, from the SVMs through actuation of the ESF Components.
MPS testing from the input sensors to the SVMs is addressed by surveillance requirements specified in LCO 3.3.1, Module Protection System (MPS) Instrumentation. The ESFAS logic and actuation circuitry functional testing is accomplished with continuous system self-testingself checking features on the SVMs and EIMs and the communication between them. The self-testingself checking features are designed to perform complete functional testing of all circuits on the SVM and EIM, with the exception of the actuation and priority logic (APL) circuitry. The self checkingself-testing includes testing of the voting and interlock/permissive logic functions. The built-in self checkingself-testing will report a failure to the operator and place the SVM or EIM in a fail-safe state.
The only portion of the ESFAS logic and actuation circuitry that is not self checkedself-tested is the APL. The manual actuation switches, enable nonsafety control switches, main control room isolation switches, override switches, and operating bypass switches do not include self checkingself-testing features and their OPERABILITY is verified by required surveillance testing. The manual actuation switches are addressed by surveillance requirements specified in LCO 3.3.4, "Manual Actuation Functions."
The ACTUATION LOGIC TEST includes testing of the APL on all ESFAS EIMs, the enable nonsafety control switches, the main control room isolation switches, the override switches, and the operating bypass switches. The ACTUATION LOGIC TEST includes a review of any alarms or failures reported by the self checkingself-testing features.
The Surveillance Frequency is controlled under the Surveillance Frequency Control Program.
NuScale B 3.3.3-9 Draft Revision 2.0