ML20076N139
| ML20076N139 | |
| Person / Time | |
|---|---|
| Site: | Crystal River  |
| Issue date: | 07/18/1983 |
| From: | Westafer G FLORIDA POWER CORP. |
| To: | Harold Denton Office of Nuclear Reactor Regulation |
| References | |
| RTR-NUREG-0737, RTR-NUREG-737, TASK-2.F.2, TASK-TM 3F-0783-15, 3F-783-15, NUDOCS 8307210209 | |
| Download: ML20076N139 (43) | |
Text
{{#Wiki_filter:_ .P..o..w...e.r July 18,1983 3F-0783-15 Mr. Harold R. Denton, Director Office of Nuclear Reactor Regulation U. S. Nuclear Regulatory Commission Washington, DC 20555
Subject:
Crystal River Unit 3 Docket Ho. 50-302 Operatinn License No. DPR-72 NUREG-0737, Item II.F.2 Insteementation for Detection of Jaadequate Core Ccoling
Dear Mr. Denton:
Florida Power Corporation (FPC) hereby provides the conceptual design; overall schedule for engineering, procurement, and installation; and the Nuclear Regulatory Commission (NRC) checklist for compliance with NUREG-0737, Item II.F.2. The above is included in the attached " Response to NRC Order for Modification of License - Section III, and Appendix A". This is submitted as stated in our letters to you dated April 15, 1983 and April 25, 1983. FPC has made significant progress in the development of a conceptual design and is able to submit to you the NRC checklist for compliance with NUREG-0737, Item II.F.2 at this time. FPC had previously stated it would be submitted by August 26, 1983. FPC has 90% confidence that the system can be installed and operational by the end of our Refuel V, which is scheduled to start in February, 1985. FPC has 100% confidence that the system can be installed and 8307210209 830718 O PDR ADOCK 05000302 f P PDR l l General Office 3201 Thrty-sourth street south. P O. Box 14042, si. Petersburg. Florda 33733 e 813-866-5151
g-g Mr. Harold R. Denton, Director July 18, 1983 Page 2 operational by the end of our Refuel VI. FPC requires NRC approval of our conceptual design and NRC checklist by September 2,1983 in order to proceed with our detailed design, procurement, and installation so-that we can fulfill our commitment to the NRC. As discussed with Mr. Ron Hernan, our Project Manager, ten (10) copies of the subject report are attached. i Sincerely, / G. R. Westafer Manager, Neclear Licensing and Fuel Management Attachments Westafer(R01)CS-1 cc: Mr. J. P. O'Reilly, Regional Administrator Office of Inspection & Enforcement, Region II U. S. Nuclear Regulatory Commission 101 Marietta Street NW, Suite 2900 Atlanta, GA 30303 1
.= ->). 1 j y RESPONSE TO NRC ORDER FOR MODIFICATION OF LICENSE - SECTION III, AND APPENDIX A RE: NUREG 0737, TMI Iten II.F.2, Inadequate ' Core Cooling (ICC) Crystal River - Unit 3 Nuclear Generating Plant Florida Power Corporation July 1983 9 Y i i 1. s 4 ', 4 e t r +-w y --gary y-p r73T-srs re--
o I RESPONSE TO NRC ORDER FOR MODIFICATION OF LICENSE - SECTION III, AND APPENDIX A RE: NUREG 0737, TMI Item II.F.2 Inadequate Core Cooling (ICC) Crystal River - Unit 3 Nuclear Generating Plant Florida Power Corporation INDEX .P, age, 1 ICC System Components 2-5 Response to Appendix A checklist, Plant-Specific Review of ICC Instrumentation Enclo sures 1. Technical Description of Existing Instruments Core Exit T' ermocouples (CETs) n a. b. Subcooling Margin Monitor (SMM) 2. Technical Description of Plant-Specific Reactor Coo} ant Inventory Tracking System (RCITS) 3. Technical Description of Plant-Specific Core Exit Thermocouple System 4. Summary of Requirements - Conformance with NUREG 0737,II.F.2, Attachment 1; and Proposed Mcdifications 5. Response to Appendix B, NUREG 0737,II.F.2 RCITS - 'With Deviations-6. Response to Appendix B, NUREG 0737,II.F.2 CETs - No Deviations 7. ICC Instrumentation Implementation Schedule l l l l
e a e Inadequate Core Cooling System for Crystal River - Unit 3_ Florida Power Corporation The CR3 Inadequate Core Cooling (ICC) system consists of the following major elements: 1. A reactor coolant inventory tracking system (RCITS) which indicates reactor vessel and hot leg coolant level when RC pumps are tripped and coolant inventory trends when RC pumps are running. 2. Extended range core exit thermocouple (CET) temperature dis-plays which indicate distribution of coolant temperature rise over all regions of the core. 3. A subcooling margin monitor (SMM) system which indicates the reactor coolant saturation and superheat temperatures. 4. Other instrumentation currently used by the operators to indicate core cooling conditions including T-hot, T-cold, T-average, RC pressure, pressurizer pressure and levei, and seconda ry side parameters. 1 I _ A
r Response to Appendix A Checklist for Plant-Specific Review of Inadequate Core Cooling (ICC) Instrumentation System 1. Description of the proposed final system, including: A final design description of additional instrumentation a. and displays. Re's ponse: Additional equipment will include analog instrumentation to measure and display coolant level in the reactor and in each hot leg. Void fraction instrumentation and dis-play equipment will be added. Core exit temperature currently is displayed by the plant c omput er. A Class lE qualified CET backup display will be added to the main centrol board together with the coolant level and void fraction indicators. All hardwired indicators are backed up by independent displays in the plant computer. All safety-related sig-nals will be electrically and physically isolated before transmission to nonsafety-related equipreent. Detailed design descriptions are included in the enclo-sures, as referenced below. y b. Detailed description of existing instrumentation systems. Res ponse: Design details of existing instrumentation were provided to the NRC in FPC Letter No. 3F-0483-19 dated April 25, 1983. Enclosures lA and IB are copies of the technical descrip-tions of existing instrumentation. Description of completed or planned modifications. c. [
Response
Conceptual design details of planned modifications were l l submitted to the NRC in FPC Letter No. 3F-0483-11 dated April 15, 1983. Specific details of the RCITS design are described in Enclosure 2. A detailed description of the proposed CET display system is included in Enclosure 3. Modifications of the CET and 94M systems are noted in Item 4. I 2 L
. _ ~ 't e 2. L A design analysis and evaluation of inventory trend instru-c,, mentation and test data to support design in Item 1.
Response
I a tor e olan inven ory water eve whc t e co an pumps are off.- - DP instruments have been used to accurately infer. liquid level for more than half a century. During that time, this relative-ly simple concept and its techniques have become well known. This extensive experience has rendered it a proven technology. DP sensing' devices have earned the reputation of being highly reliable, rugged, and easy to maintain. In recent decades, j they also have proven to be insensitive to radiation exposure. They-have been and are being used routinely in water level measurement in light water reactors where they provide safety - functions for SCRAM, containment isolation, emergency core cooling system initiation, automatic depressurization system initiation, recirculation pump shutoff, and main steam iso-lation valve closure. They also have been used to determine liquid level in +he pressurizet in tests conducted in the loss -of fluid test (LGFT) facility. A number of tests have been conducted at the Semiscale Test Facility to further test their performance. A design analysis of inventory trending methods with RC pumps running is contained in Babcock & Wilcox (B&W) Document No. 77-11?7950-00, Feasibility Study of Inventory Trendir.g Methods With RC Pumps Operating, October 1982. We plan to use pump power to infer density. j 3. Description of tests planned and results of tests completed 4 for evaluation, qualification, and calibration of additional ins trumentation.
Response
For RCPs operating, using pump motor' power: 'A description cover-l ing this question is contained in B&W Document No. 77-1137950-00, l Feasibility Study of Inventory Trending Methods With RC Pumps i Operating, October 1982. l-For~ RCPs off, using DP instruments to indicate" RC inventory: No e tests have been planned or conducted. DP sensing instruments l have been proven to be reliable, easy to maintain, and routinely f
- used uin water level measurement in the nuclear industry (refer l
to Response 2 above). No ' testing is ' considered necessary for evaluating or calibrating these instruments to support use in coolant inventory trending applications. I 3 1 I i j ~
S I All environmental qualification tests and documentation of results will be in accordance with IEEE 323-1974, Sections 6.3 and 8.0. Tests for equipment evaluation will be described in the procurement specifications, and test calibrction will be described in the plant surveillance procedures (SP series). 4. Provide a description covering the evaluation of conformance with NUREG 0737,II.F.2, Attachment 1 and Appendix B. Response: is a summary of requirements and an evaluation of conformance with NUREG 0737,II.F.2, Attachment 1, for the CETs and subcooling margin monitors. includes a chedklist of deviations and proposed modifications. Enclosures 5 and 6 evaluate the conformance of the proposed RCITS and CETs to Appendix B. All new Class 1E equipment required for the ICC instrumenta-tion system will be qualified in accordance with NUREG 0737, Appendix B, as modified by II.F.2, Attachment 1. Existing Clans IE equipment not presently qualified will te qualified in place or will be replaced with new qualified equipment. 5. Describe computer, sof tware, ar,d display functions associated i with ICC monitoring in the plant. kesponse: The computer is equipped to display a core map, indicating the temperature of all CETs, and highlighting the single highest 4 value in colec. CETs may be digitally trended in operator-selected groups. Four CETs may be selected for trending on analog recorders. The computer will provide a backup calcu-lation of void fraction. A digital trend display will be dVailable on demand. The system is redundant, that is, the central processor is backed up by a second processor for reliability. The computers j are energized from a high reliability uninterruptible power source which is battery backed. 6. Provide a proposed schedule for installation, testing, and calibration and implementation of any proposed new instrumenta-tion or information displays.
Response
The proposed schedule for these items is provided in Enclo-sure 7. 4
e 1 7. Describe guidelines for use of reactor coolant inventory tracking system, and analyses used to develop procedurec.
Response
B&W will revise and update its Abnormal Transient Operating Guidelines (AT0G), Document No. 74-1126473-00. This document has been forwarded previously to the NRC for review. Enclo-sure 7 provides the schedule for revision. Emergency Operating Procedures are being developed from the ATOG. 8. Operator instructions in emergency operating procedures for ICC and how these procedures will be modified when final monitoring system is implemented.
Response
Emergency Operating Procedures, including ICC, presently are being revised in accordance with the ATOG. Training in these new procedures for the operators will be conducted at the plant's training center. When the final monitoring system is approved, the ATOG and Emergency Operating Procedures will be revised to include the additicac/rodifications. Enclosure 7 provides the schedule for training of operators. 9. Provide a schedule for additiocal subrittals required.
Response
Neither the Combustion Enginecting HJTC system nor the Westinghouse dp systec is buing considered. A detailed description of the proposed RCITS is provided $n our response to Item Ic. No additional technicel submittals are anticipated. i l I 5
ENCLOSURE 1A 4 TECHNICAL DESCRIPTION OF EXISTING CORE EXIT THERM 0 COUPLES' DESIGN AS ADDRESSED IN IMI ITEM II.F.2, ATTACHMENT 1, IN APPENDIX A TO THE ORDER FOR MODIFICATION CRYSTAL RIVER 3 FLORIDA POWER CORPORATION k 4 e f-u WPC/6-4B/9834 j og ~ v----mey'qt-At y w M
i-1. DIAGRAM OF CORE EXIT THERMOCOUPLE LOCATION A diagram of the incore monitoring assembly locations is presented on Drawing No. 86522B. These assemblies each contain one core exit thermocouple (CET). A total of 52 CETs are distributed throughout the core. 2. DESCRIPTION OF PRIMARY OPERATOR DISPLAYS The primary operator display of CETs is provided by a core map dia-gram on the plant computer CRT monitor. The diagram includes all 52 CET temperature readings over a range of 0* to 900*F. Any tem-perature exceeding a high alarm limit (700*F) is alarmed and the hottest temperature is highlighted in color. Alarmed values flash in red until acknowledged by the operator. A printed hard copy of the core map may be requested by the operator. All alarmed values are printed on the alarm typer. Any CET or a group of CETs may be digitally trended on a line printer. Any single CET may be time trended in analog format on the CRT dieplay. Up to four CETs may be time trended on analog strip chart recorders. An independent and separate recording system provides alarming capability for all 52 CETs. A printed record of all CET temperatures over a range of -35* to 2,490*F is available on demand. 3. IMPLEMENTATION OF THE BACKUP DISPIAY Two subcooling margin monitor (SMM) digital displays are located on ) the main control board. These instruments acquire the hot leg (T } h and cold leg (T ) temperatures and the reactor pressure at each loop to calculaEe the corresponding saturation temperature (Tsat). Each monitor displays the degrees of subcooling of one loop continu-ously and the degrees of subcooling of the other loop on demand. In addition to T and T the hottest CET selected from a group of six is connected to eac0,SMM. These 12 CETs have been selected to h provide representative temperatures from each core quadrant and the central region. The location of these CETs is identified on the enclosed marked-up copy of Drawing No. 86522B. The hottest CET temperature over a range of 0* to 1,023*F is displayed on demand. Tsat corresponding to the hottest CET also is displayed on demand. The instruments include a low margin to saturation alarm indicator and an alarm signal to the plant annunciator and event recorder. Verification of SMM meter operability is performed semiannually by performing a calibration procedure using Surveillance Procedure SP-122.
4. USE OF THE PRIMARY AND BACKUP DISPLAYS Refer to Enclosure 3. 5. NUREG 0737 CRITERIA Refer to Enclosure 6. 6. PARTS OF SYSTEM POWERED FROM CLASS lE POWER SOURCES Thermocouple transmitters for the 12 CETs used by the subcooling margin monitors are powered from the same vital power sources as the respective SMMs. The CRT displays are powered from the battery-backed plant _ computer uninterruptible power supply. CETs connected only to the plant computer are not isolated. 7. ENVIRONMENTAL QUALIFICATION CRITERIA Refer to Enclosure 3. l t 2 i t t v
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r ENCLOSURE IB TECHNICAL DESCRIPTION OF EXISTING SUBC00 LING MARGIN MONITORS AS ADDRESSED IN ml ITEM II.F.2 AND NUREG 0737, APPENDIX B, TO THE ORDER FOR MODIFICATION CRYSTAL RIVER - UNIT 3 FLORIDA P0i4ER CORPORATION WPC6-4B/7567
1.0 ENVIRONMENTAL QUALIFICATION The subcooling margin monitors (SMMs) were tested by Babcock & Wilcox (B&W) for seismic and environmental qualification. The devices meet the requirements for installation in an eIectronic equipment room and the control room. 2.0 SINGLE-FAILURE ANALYSIS Two independent SMMs are provided for redundancy. Sensors and instru-mentation also are independent and redundant. The design of the SMM considered the most likely cause of failure is loss of the internal clock. A circuit is incorporated that will de-tect the loss of the clock at the display and will blank the display. 3.0 CLASS 1E POWER SOURCE The SMMs, sensors, and instrumentation are powered from separate vital (Station Class 1E) power sources. 4.0 AVAILABILITY PRIOR TO AN ACCIDENT Each SMM is capable of being manually switched to either loop. Because the SMMs are redundant, t. hey are designed to provide 99-percent availa-bility for each channel. 5.0 QUALITY ASSURANCE B&W considers the SMH to be a commercial-grade item, not a basic compo-nent as defined in 10CFR21. B&W hac certified that the SMMs conform to its quality assurance plan. 6.0 CONTINUOUS INDICATION The SMMs can be selected either to provide continuous indication of the degrees of subcooling or to provide other system parameters. An additional microprocessor-driven CRT display of saturation curves (both loops) is located in the control room. There are no plant opera-tor controls for this display. -7.0 RECORDING INSTRUMENT OUTPUTS The SMMs provide no outputs for recording. 8.0 IDENTIFYING INSTRUMENTS The SMMs are located in the main control board and are suitably identified. l i
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= - _ _ _. ENCLOSURE 3 P TECHNICAL DESCRIPTION OF PROPOSED CORE EXIT THERMOCOUPLE SYSTEM DESIGN RESPONSE TO II.F.2, ATTACHMENT 1 (- s 5 E e ( t-p-: 1. s
l. Diagram of Core Exit Thermocouple Location A diagram of the in-core monitoring assembly locations is presented on Babcock and Wilcox (B&W) Drawing No. 86522B. These assemblies each contain one CET. A total of 52 CETs are distributed through-out the core as shown. 2. Description of Primary Operator Displays The primary operator display of CETs is provided by a de-a. mandable core map diagram on the plant computer CRT monitor. The temperature at each of the 52 CET locations is displayed. Bad readings are identified. b. The highest temperature of all operable thermocouples is high-lighted in color and is updated continuously whenever the cae.- .aap is displayed. c. A hard copy of the core map is printed on demand by the com-puter line printer. The temperature of all CETs will be dis-played over a range of 0*F to 2,500*F. d. The computer provides a capability to display or to print a temperature-time digital trend history for any CET, singly or in groups, by operator selection. In addition, four analog strip chart recorders are driven by the computer. Each of these recorders can provide a trend record of any CET. Any CET temperature exceeding a 700 *F alarm limit will be e. alarmed on the dedicated alarm monitor and alarm printer. If the core map diagram is requested, the alarmed CET will be displayed in color. This capability is consistent with CR3 operating procedures. f. Human factor considerations were applied to the design of the display system. CET displays are consistent with all CR3 plant computer displays. 3. Description of Backup Displays Three multipen analog temperature recorders will be provided on the main control board. A minimum of 16 CETs, 4 from each core quadrant, will be recorded continuously over a range of 0*F to 2,500*F. The recorders will have alarm capability, can automatically change chart i speed on alarm, and will detect inoperable CETs. Two subcooling margin monitors are located on the main control board. These instruments continuously display saturation temperature for each loop. In addition to displaying saturation temperature, each 1 1
instrument can display on demand the hottest CET selected from a group of six CETs. A total of 12 CETs have been selected to pro-vide representative temperatures from each core quadrant and the control region. These instruments display temperatures over a range of 0*F to 1,023*F, well above saturation temperatures. 4. Use of Primary and Backup Displays A human factors analysis will be conducted to determine the loca-tion and display of alarms. a. During normal operations, the operator will have a continuous indication of the subcooling margin. b. Af ter an alarm condition by the SMM, the operator will be instructed in the emergency operating procedure to commence monitoring the CET primary display. The backup display on Channel B will be checked manually during the progress of the transient. c. The operators will be trained in the revised abnormal transient operating guidelines and the revised emergency operating proce-dures prior to implementation of the new instrumentation and displays. d. Other alarms occurring during the emergency will be prioritized in both the abnormal transient operating guidelines and the emergency operating procedures. 5. NUREG 0737 Criteria The core exit thermocouples have been evaluated to the criteria of NUREG 0737, Appendix B. The results of this evaluation are described in Enclosure 6. 6. Power Sources The primary and backup display channels will be electrically inde-pendent, energized from independent power sources, and physically separated in accordance with Regulatory Guide 1.75 up to and in-cJuding the isolators. The primary display and computers are not Class lE, but are energized from a battery backed high-reliability uninterruptible power supply. The backup display and its power sources will be Class IE. CETs connected only to the plant computer will not be isolated, since they are unpowered and are not associated with safety sys-tems. CETs connected to both safety and nonsafety systems will be isolated prior to the connection with nonsafety systems. 2
7. Environmental Qualification There have.been no problems with the existing in-core probe as-semblies. One-half of them have been replaced during the 1983 refueling outage with similar units. During the next refueling outage, all of the existing in-con-tainment cable for the in-core probe assemblies will be replaced with qualified cable. Also, during future outages, the in-core probe assemblies will be replaced with qualified units. 3-i
ENCLOSURE 4
SUMMARY
OF REQUIREMENTS; CONFORMAN.CE WITH NUREG 0737, II.F.2, ATTACHMENT 1; AND PROPOSED MODIFICATIONS 1. CORE EXIT THERMOCOUPLES (CETs) a. Requirements A minimum of 4 CETs from each quadrant is required. They should be environmentally qualified. Their outputs should be electrically isolated and physically separated from nonsafety-related circuits. The primary operator display of core exit temperature should be a core map available on demand. Temperature range should extend from 200*F to 1800*F minimum. A temperature-time trend history capability should be available on demand. The alatuing capability should be consistent with operator procedures. The display must be human factor designed to provide rapid access to displays. A backup CET display, qualified for Category 1E service, should be provided to display an additional 16 temperatures in 6 minutes. The temperature range should be 200*F to 2300*F. It should be powered from a separate 1E power source. b. Conformance of Existing Equipment The CETs, connectors, and cables are not environmentally qualified category 1E devices. Isolation and separation are not provided. The temperature range for CETs in the plant computer (primary display) is O'F to 900*F, which is less than the 1800*F required. An analog temperature-time trending display capability is not provided, but temperatures can be time recorded on f computer output analog recorders. Access to operator displays should be improved. A qualified backup display is not provided. An existing Esterline-Angus data logger does not meet the requirements. I c. Proposed Modifications Existing thermocouple cables will be replaced by qualified cables as part of the ICC modifications. CETs will be replaced by environmentally qualified thermocouples as the in-core probe assemblies are replaced during future refueling outages. 1
The primary display need not be qualified for Category lE service. However, separation in accordance with Regulatory Guide (RG) 1.75 will be provided between the primary and the backup. Isolators will be provided between the backup CETs and the computer. Seismically qualified racks and equipment, including type K thermocouple converters and analog isolators will be used to accomplish this. A Category lE qualified temperature display will be provided for backup. It will be located for rapid access by the operator and permit selective reading of 16 temperatures within 6 minutes. Qualified devices which meet the require-ments are supplied by TI (Tigraph 200). 2. SUBC00 LING MARGIN MONITORS a. Requirements NUREG 0737 II.F.2 provides little guidance to the design criteria for subcooling margin instrumentation (also called saturation temperature meters, Tsat). RG 1.97, Revision 2, specifies a range of 200*F subcooling to 35'F superheat. It also places SMM in Category 2. b. Conformance of Existing Equipment Although there is no requirement for isolation and separation for Category 2 instrumentation, if it is determined that the input signals for the SMM are derived from safety systems, proper isolation and separation up to and including the iso-lators will be provided. c. Proposed Modifications FPC will verify the existing conditions and correst them, as required. 2
~ j II.F.2, ATTACHMENT 1 CHECKLIST (FOR CORE EXIT THERMOCOUPLES) Criteria NonConformance Proposed Modifications 1. Provide sufficient CETs with proper distribution. 2. Primary display: a. -Core map b. Continuous display c. Range 200*F to Insufficient range Modify software. 1,800*F Direct readout - hard copy d. Trend capability e. Alarm capability f. Human factors design No rapid access 1. Detailed analysis 2. Add keyboard func-tion keya. 3. Backup display Not qualified Add qualified system. 4. Human factors analysis: a. Normal / abnormal use Normal use not Modify procedures. included b. Emergency use Insufficient Modify procedures, detail c. Training use Not included Modify procedures. d. Prioritization Not included Modify procedures. 5. Conformance to Appendix B See separate enclosure. 6. Independent ' power sources 7. Instrument qualification See Enclosure 3 See Enclosure 3 8. 99-percent availability New equipment will 9. Quality Assurance meet Regulatory Guide QA requirements. L --
+ ENCLOSURE 5 RESPONSE TO APPL 5 DIX B 0F NUREG 0737, II.F.2 Design and Qualification of the Reactor Coolant Inventory Tracking System (RCITS) 1. Environmental / Seismic Qualification The RCITS will be environmentally qualified in accordance with Regulatory Guide (RG) 1.89 (NUREG 0588), with the seismic portion of the qualification in accordance with RG 1.100, except as noted herein (see deviations). 2. Single Failure The RCITS will be designed so that no single failure of the instru-ments or auxiliaries prevents the operator from determining the safety status of the unit. Redundancy is provided by dual instrument t rains. The two dif ferential pressure sensing trains do have taps in common at the penetrations in the reactor vessel head and the decay heat suction line; however, there is a very low probability of tap failure (see deviations). 3. Class 1E Power Ecurces Each of the redundant dif ferential pressure systems used to infer reactor coolant level with RCPs tripped will be electrically pow-ered independently from separate Class lE sources. The coolant in-ventory trending system used with RCPs running will be non-Class 1E (see deviations). ( 4. Availability Prior to an Accident RCITS it.strument channels will be available prior to an accident, except as provided in paragraph 4.11, Exemption, in IEEE Standard 279. Y 5. Quality Assurance Requirements The QA requirements will be those imposed by the quality programs as stated in Section 1.7 of Crystal River - Unit 3 FSAR. 6. Continuous Indications ( RCITS instrumentation will provide a continuous indication of re-actor coolant inventory trending with RCPs running or tripped.
o 7. Recording Instrumentation RCITS instrumentation will provide analog strip chart records of reactor coolant inventory trending with RCPs running or tripped. 8. Identification of Instritments RCITS instruments mounted on the control panels will be speci-fically identified so that the operator can easily discern that they are for use under accident conditions. 9. Isolation The transmission of signals from Class 1E sensors to any non-Class IE instrument or device will be through isolation devices that are designated as part of the monitoring instrumentation. 10. Checking Operational Availability The Class 1E qualified electronic analog equipment racks will be located outside of containment for accessibility. Input and output terminals on the racks will be located at the front. Each of the input modules will have provision for insertion of a test jack, which will disconnect the normal transmitter input and connect a test input. This will be used for calibration, troubleshooting, and checking the operational availability of each monitoring channel. 11. Servicing, Testing, and Calibration Servicing, testing, and calibrating programs will be specified later in a technical specification change. See ICC Instrumentation Schedule for planned date of submittal. A capability for testing during power operation will be provided for those instruments where the required interval between testing will be less than the normal time interval between generating sta-tion shutdowns. Refer to Item 10 for details. 12. Administrative Control of Removal from Service Wherever means for removing channels from service are included in the design, the design will include locked cabinets and discreet distribution of keys to provide administrative control of the access to those removal means.
- 13. Administrative Control of Access to Adjustments i
Administrative control of the access to all setpoint adjustments, module calibration adjustments, and test points also will be accom-p11shed through the use of locked cabinets and discreet distribution of keys. 2
) o * * '. 14. Minimizing Anomalous Indications During normal operations with the RCPs runi.ing, or during the vent-ing operation, anomalous indications will be minimized by the trending characteristics of the void fraction monitoring system. Only a continued trend towards an undesirable condition, not a transitory deviation from normal, will cause an anomalous indica-i tion. When the RCPs are tripped, the coolant level indicators will pro-vide real indication of coolant inventory; therefore, anomalous indications will be genuine indications of anomalous inventory conditions and should not be confusing to the operator. 15. Detecting, Locating, and Correcting Malfunctions Instrument selection, location, and system design will be such as to facilitate the recognition, location, replacement, repair, or ad-justment of malfunctioning components or modules. Refer to Items 10 and 11 for details. 16. Direct Measurement of Desired Variables There is no practical means to directly measure all of the desired variables affecting the monitoring of coolant inventory. In the RCITS, measurement of the primary variables used to monitor coolant inventory are inferred from RCP motor power in normal operation and hydrostatic pressure when the RCPs are tripped. Measurements of the secondary variables of temperature and pressure used in the coolant inventory algorithms are made directly. 17. Normal / Accident Monitoring RCITS instrumentation covers the full range of coolant inventory for normal and accident situations. Monitoring of void fraction trends with the RCPs running, and coolant level in the reactor vessel and hot legs when the RCPs are tripped provides adequate instrumentation sensitivity under both normal and accident conditions. 18. Periodic Testing Same as Items 10 and 11. I 3
. ~. RESPONSE TO APPENDIX B, NUREG 0737, II.F.2 DEVIATIONS 1. Environmental Qualification / Class IE Power Source - RCITS with Reactor Coolant Pumps (RCPs) Running RCP motors and their associated electrical circuits currently are powered from non-Class IE sources and are not environmentally qual-ified in accordance with IEEE 323-1974. Since the RCITS is not a protection system, but a monitoring system with reliable backup f rom the core exit thermocouples and the saturation margin monitor, it is not intended that the RCP motors and their circuits be up-graded to meet the requirements of IEEE 323-1974. Rather, since the cost of such an upgrade would be exorbitant in terms of finan-cial expenditure, downtime, and man / rem exposure, it is intended to make the computational and readout devices used with the RCP motor power inputs non-Class 1E also. For maximum reliability in the RCITS with RCPs running, separate sets of analog computational devices will be used for each RCP loop and 100-percent computational backup will be provided by the com-puter, which will perform totally independent calculations and provide void trending indication upon demand. 2. Single-Failure Analysis - RCITS With RCPs Tripped ( Single, rather than dual, pressure taps are provided in the reactor vessel head and in the decay heat suction line. Since the RCITS is a monitoring system, not a protection system, it is considered more important to safety and reliability to minimize the number of pene-trations in the reactor coolant system than to increase them for { the sake of redundancy. Instead, the taps will be designed in size, configuration, and selection of construction material to minimize the possibility of plugging or leaking. From these common taps, separate connections will be made to completely redundant instrumentation with totally independent electrical power sources so that no single failure of the instruments, auxiliaries, or power f sources will prevent the operator from being presented with the information necessary for him to determine the safety status of the plant, to take corrective action, and to maintain a safe condition. s J
co e a ENCLOSURE 6 RESPONSE TO APPENDIX B 0F NUREG 0737, II.F.2 Design and Qualification of the Core Exit Thermocouple (CET) System 1. Environmental Qualification The CET instrumentat' ion will be environmentally qualified, except for the primary display and computers beyond the isolators. 2. Single-Failure Analysis Redundancy will be provided by independent primary and backup sys-tems. The primary system computer itself is redundant (see para-graph 5 in Response to Appendix A Checklist). Analog recorders will be provided for the backup system. The saturation meters, although not environmentally qualified, provide additional backup display consisting of the two highest CET temperatures selected from among 12 CETs, independent from the backup system. 3. Power Sources The primary and secondary systems will be energized from separate vital buses. The primary system is energized from a battery-backed uninterruptible power supply. 4. Availability Both channels will be available prior to an accident except as pro-vided in paragraph 4.11, Exemption, as defined in IEEE Standard 279. l 5. Quality Assurance (QA) The QA requirements will be those imposed by the quality program, as stated in Section 1.7 of CR3 FSAR. 6. Continuous Indication Continuous indication will be provided by the recorders in the backup system. 7. Recording L The backup system analog recorders will provide trend records. Hard copy of the computer display is available upon demand. L.
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8. Identifiestion ICC instruments will be located together on the main control board. The CET recorders will be identified for use under accident conditions. 9. Isolation Qualified isolators will be provided between Class 1E safety-related devices and nonsafety-related devices. L 4 4 C l T l 2 1
+ e ENCLOSURE 7 ICC INSTRUMENTATION IMPLEMENTATION SCHEDULE Month / Year o Complete operator guidelines, including analysis used in developing procedures 12/84 o Complete procurement of instrumentation 12/64 o Commence installation of instrumentation, 2/85 o Complete operating and emergency procedure modifications 2/85 o Submit technical specification 2/85 o Commence training of RO/SRO 1/85 o Complete installation 4/85 o Complete testing and calibration 4/85 o Complete training of R0/SRO 4/85 o Commence operation Dependent on date of NRC approval. __}}