ML17046A421
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7.5 SAFETY-RELATED DISPLAY INSTRUMENTATION 7.5.1 Description Table 7.5-1 lists the major process parameters available to the operator to enable him to perform required manual functions and to determine the effect of manual actions taken following a reactor trip due to operational occurrences or accident conditions discussed in Section 15. The table lists the readouts required to maintain the plant in a hot shutdown condition or to proceed to cold shutdown within the limits of the Technical Specifications. Reactivity control after operational occurrences will be maintained by administrative sampling of the reactor coolant for boron to insure that the concentration is sufficient to maintain the reactor subcritical. As shown in the table, sufficient duplication of information is provided. The information is part of the operational monitoring of the plant which is under surveillance by the operator during normal plant operation. This is functionally arranged on the control board to provide the operator with timely and pertinent information on plant conditions. Comparisons between duplicate information channels or between functionally related channels will enable the operator to readily identify a malfunction in a particular channel. The information system that provides the signals to the indicators and/or recorders listed in the table is described in Section 7.2, with the exceptions of the refueling water storage tank (RWST) level and the steam generator wide range water level. The Unit 1 RWST level is indicated by two independent single-channel systems (Unit 2 consists of four independent single-channel systems). Each steam generator water level (wide range) is indicated by independent single-channel systems and recorded by a single-channel system. No automatic protection or control functions are provided by these devices. The remaining signals are obtained through isolation amplifiers from the protection channels. 7.5-1 SGS-UFSAR Revision 16 January 31, 1998 This allows the automatic protection system to function independently of any failure of the non-protection equipment and provides the moat reliable means of obtaining the information. There is no basis for aaauming that the occurrence of an accident itself degrades the Display System. Therefore, the status and reliability of the information is known to the operator before, during, and after the accident. The design criteria used in the Display System are listed below: 1. Range and accuracy requirements are determined through the analyses of postulated occurrences as described in Section 15. The display meets the following requirements: a. The range of the readouts extends over the maximum expected range of the variable being measured. b. The combined indicated accuracies are within the errors assumed in the safety analyses. 2. Power for the display instruments is obtained from the 115 V power system described in Section 8. 3. Those channels which have been determined to provide useful information in charting the course of events are recorded. Table 7.5-2 lists the indications available to the operator to monitor significant plant parameters during normal operation. 7.5.2 Bypass Indication The containment Spray System is a typical Engineered Safety Features (ESF) System which incorporates status indications. The spray pumps and the system motor-operated valves have open/close 7.5-2 SGS-UFSAR Revision 6 February 15, 1987 lights on the main control console pushbutton stations and loss of control voltage alarms in the Auxiliary Alarm System. The spray additive tank valve, 1CS14, also has an "off-normal" position alarm on the overhead annunciator. Any equipment taken out of service for maintenance or other purposes is under the administrative control of the plant operating personnel, which includes logging of unavailable equipment and covering the control station with a plastic cover. Bypasses of the Solid State Protection System (SSPS) outputs associated with the spray system are described below. In general, if any analog channel in the ESF Actuation System is taken out of service for any reason, the channel is placed in the tripped mode, and a channel trip status light is lit in the Control Room. In addition, an alarm will sound and an associated annunciator panel light will be lit. This holds true for the containment pressure channel associated with safety injection and steam line isolation functions. The channel bistable output relays associated with the containment spray function are not tripped, to reduce the possibility of inadvertent actuation, but are bypassed for test and maintenance purposes. An alarm indicating a bypassed condition is provided for each channel. The plant design includes one or a combination of the following indications to show the operator the status of plant systems and to highlight the existence of an incorrect configuration: 1. Indication lights (red-open and green-closed) at the push-button control station for valves. 2. A separate monitor light indication grouped with lights for other devices having a similar function such that the lights in the group are all on or are all off to provide for quick operator evaluation of systems status 7.5-3 . SGS-UFSAR Revision 6 February 15, 1987 during the injection or recirculation mode of a Loss-of-Coolant Accident (LOCA). 3. Auxiliary annunciation redundant to the above indications which serves to alert the operator of the improper state, relative to plant conditions, of a critical device (pump, valve, etc.). By lookinq at equipment status indications, an operator can determine if components in the ESF Systems have been isolated or bypassed. The followinq alarms have been provided in the Control Room to indicate test of bypass for ESF Systems: Spray channel comparator tripped (4 alarms) Spray channel comparator on test (4 alarms) Solid state protection Train A trouble Solid state protection Train B trouble Solid state protection Train A on test Solid state protection Train B on test Reactor protection channel on test (4 alarms) Nuclear instrument channel on test Rod position indication on test Safequards Equipment Control Systems on test (3 alarms) NIS loss of detector of compensation voltage (5 alarms) 1 (2) PRl CHANNEL UNSAFE (comparator on test) 1 (2) PR2 CHANNEL UNSAFE (comparator on test) 1 (2) PR1 1/2 TRIP (channel comparator tripped) 1 (2) PR2 1/2 TRIP (channel comparator tripped) 7.5-4 SGS-UFSAR Revision 17 October 16, 1998
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- NIS source range high flux at shutdown blocked NIS source and intermediate range trip bypass Diesel generator urgent trouble (3 alarms) Diesel generator fuel oil day tank trouble 4 kV vital bus alarms (18 alarms) The following lights on the status panel indicate bypass conditions: Source range trip blocked (2 lights) Source range Trains A and B trip blocked Intermediate range trip blocked (2 lights) Intermediate range trip A and B trip blocked Power range (low setpoint) Trains A and B trip blocked Steamline isolation Trains A and B safety injection blocked Safety injection blocked Trains A and B Automatic Safety Injection blocked Overpower rod stop manual bypass (4 lights) Steam dump block T average bypass The system has been designed to meet the intent of IEEE Standard 279-1971, Paragraph 4.12; that is, bypasses are removed automatically when permissive conditions are not met . 7.5-5 SGS-UFSAR Revision 11 July 22, 1991
7.5.3 Evaluation
An evaluation of Salem Unit 2 Instrumentation Systems to determine the degree of compliance with Regulatory Guide 1.97 has been completed. Since the Salem design bases for instrument systems were developed and approved by the NRC significantly prior to the issuance of this ;uide, the evaluation was based on compliance with the overall intent of the Guide. Demonstration of compliance with the intent of the Regulatory Guide required that any specific differences between the Salem design bases and those of the Regulatory Guide be identified. The identification of these differences is specified in Section 7.5.3.1. The key elements of the overall evaluation can be summarized as follows: 1. Compliance of existing systems and instrumentation is based upon meeting the intent of the Regulatory Guide. 2. Compliance of new equipment is based upon application of the Regulatory Guide to the extent that existing design can accommodate the change without compromising the existing system. 3. Previous commitments to modify existing equipment or to add new equipment were considered (e.g., NUREG-0588 and NUREG-0737) in the context of those commitments which pre-date Regulatory Guide 1.97. The results of this evaluation have been classified into five basic types of "compliance levels." These compliance levels have been selected to illustrate the resolution actions planned for the equipment to demonstrate the overall plant compliance with Regulatory Guide 1.97. This information is included in Sections 7.5.3.2 and 7.5.3.3. 7.5-6 SGS-UFSAR Revision 6 February 15, 1987 * * *
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- 7.5.3.1 Identification of Design Basis Differences from Regulatory Guide 1.97 To establish a baseline set of criteria for this evaluation, Regulatory Guide 1. 97 recommendations have been reviewed for similarity to the Salem Station design bases. In those instances where the Salem bases agree with Regulatory Guide 1.97, no differences are listed below. For those cases which involve differences, a comparison is provided below to demonstrate that the intent of the Guide is adequately achieved. 1. The Salem Station design bases were effectively established prior to issuance of the Regulatory Guides referenced in Regulatory Guide 1.97. Although the Salem station conforms to the intent of the Regulatory Guides, strict compliance has not been required. In many cases, the Guides have been revised to incorporate subsequent revisions of referenced standards; and in some cases, the Guides are not applicable to the previously approved design (e.g., Regulatory Guide 1.75). For the purpose of compliance with Regulatory Guide 1.97, the Salem design will conform with the intent of the referenced Guides and Standards to the same extent as specified in previous responses to the NRC on the subject documents
- 2. Regulatory Guide 1.89 -"Qualification of Class lE Equipment for Nuclear Power Plants." The Salem Station review basis is NUREG-0588, category II for existing instrumentation and NUREG-0588, Category I (i.e., IEEE Standard 323-74) for new equipment. Evaluations for equipment in harsh environments have been completed. Evaluations for noncontrolled benign environments will be completed per NRC established schedules
- 7.5-7 SGS-UFSAR Revision 6 February 15, 1987 Recorders, indicators, and other instrumentation located in controlled benign environments, such as the Control Room, have been considered as meeting the intent of Regulatory Guide 1.97, pending the completion of the NUREG-0588 benign environment review. 3. Regulatory Guide 1.100 -"Seismic Qualification of Electric Equipment for Nuclear Power Plants." The Salem Station review basis is IEEE standard 344-71 for existing equipment and IEEE standard 344-74 for new equipment. 4. Regulatory Guide 1.75 -"Physical Independence of Electric Systems.* The Salem station Electric Systems do not conform to the recommendation in Regulatory Guide 1. 75, since this was not an original design criterion. New equipment will be integrated into our existing separation provisions. The salem separation criteria have been approved by the NRC staff as described in Section 7.8 of the original and Supplement 1, and Section 8. 4. 5 of Supplements 3 and 4 of the Safety Evaluation Report. 5. Regulatory Guide 1.32 -"Criteria for Safety-Related Electric Power systems for Nuclear Power Plants." The Salem Station review basis is IEEE Standard 308-71, "Class lE Electric Systems for Nuclear Power Generating Stations." 6. Quality Assurance: Regulatory Guides a. Regulatory Guide 1.28, "Quality Assurance Program Requirements (Design and Construction)" Revision 2, dated February 1979. The Salem station review basis is Safety Guide 28, which endorses ANSI 45.2.1 of 1971. 7.5-8 Revision 15 June 12, 1996 * * *
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- SGS-UFSAR b. Regula tory Guide 1. 38, "Quality Assurance Requirements for Packaging, Shipping, Receiving, Storage, and Handling of Items for Water-Cooled Nuclear Power Plants," Revision 2, dated May 1977. The Salem Station review basis is Regulatory Guide 1.38, Revision 1, dated October 1976. c. Regulatory Guide 1.64, "Quality Assurance d. e. Requirements for the Design of Nuclear Power Plants," dated June 1976. The Salem Station review basis is Regulatory Guide 1.64, Revision 0, dated October 1973. Regulatory Guide 1.123, "Quality Assurance Requirements for Control of Procurement of Items and Services for Nuclear Power Plants,11 dated July 7, 1977. The Salem Station review basis is ANSI 45.2.13, of 1976 . Regulatory Guide 1.144, "Auditing of Quality Assurance Programs for Nuclear Power Plants," Revision 1, dated September 1980. The Salem Station review basis is ANSI 45.2.12, Draft 4, Revision 2. f. Regulatory Guide 1.146, "Qualification of Quality Assurance Program Audit Personnel for Nuclear Power Plants," dated August 1980. The Salem Station review basis does not include a commitment to Regulatory Guide 1.146. Unique Identification: The instruments are not specifically identified on the control panels as those intended for use under accident conditions. The instrumentation on the control panels in the Salem Control Room is presently grouped on a functional basis . Additional markings could add confusion to a control 7.5-9 Revision 6 February 15, 1987 panel layout that was favorably reviewed during the NRC "Human Factors Review of the Salem No. 2 Unit Control Room" in March 1980. 8. Regulatory Guide 1.118 -"Periodic Testing of Electric Power and Protection Systems". The Regulatory Guide invokes the requirements of IEEE Standard 338-1975, which is applicable to protection for Regulatory Guide 1.97, is not considered to be part of the Protection System and does not require all of the testing specified in IEEE Standard 338. The plant equipment Guide 1.97 being used for compliance with Regulatory has been designed to incorporate testing as discussed in Section 7.2. Testing capabilities frequencies will be in accordance with the applicable Technical Specifications. 9. Type 11A11 Variables (Plant Specific) The The definition of Type "A" Variables given by Regulatory Guide 1.97, Paragraph 1.1 is: 11Those variables to be monitored that provide the primary information required to permit the control room operators to take the specified manually controlled actions for which no automatic control is provided and that are required for safety systems to accomplish their safety functions for design basis events." The Salem Emergency Operating Procedures were reviewed to determine which Regulatory Guide 1. 97, Type "A" parameters are required using the following baseline interpretation of Regulatory Guide 1.97, Paragraph 1.1. operating procedures specify certain operator verification of automatic actions and, if the automatic actions have not been performed (presumably due to system 7.5-10 SGS-UFSAR Revision 6 February 15, 1987 * * *
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- failure), the operator is required to manually perform those actions. The parameter selection does not include either the verification step or the manual backup action. The parameter selection includes those required for operator actions needed for system functioning where no automatic signal/system exists. Where important, the manual Type "A" operator actions must be monitored to assure that the action has been performed. This monitoring of Type "A" operation is performed by "Type B" variables as defined by Regulatory Guide 1.97. In reviewing the Emergency Operating Procedures, the event "end point" for parameter selection is a stable hot condition for all events except LOCAs (large or small) that cannot be isolated. The "end point" for LOCAs that cannot be isolated is a cold depressurized condition. See Table 7.5-3 for an index of Class "A" Variables. 7.5.3.2 Regulatory Guide 1.97 compliance Levels The evaluation revealed varying degrees of compliance with Regulatory Guide 1.97 which were classified into five "compliance levels." These classifications evolved from consideration of the design bases, existing NRC commitments and specific new changes, where possible, to meet the Regulatory Guide. The overall results of this effort are summarized in Table 7.5-4. Table 7.5-5 provides justification for Regulatory Guide nonconformances. Most Regulatory Guide 1.97 variables are displayed on the Safety Parameter Display System (SPDS). SPDS monitors are located in the Unit l and Unit 2 Control Rooms, Technical Support Center and the Emergency Operations Facility. The SPDS is discussed in Section 7.10. The description of each "compliance level" is provided below
- 7. 5-11 SGS-UFSAR Revision 14 December 29, 1995 Items in Compliance The items categorized under this heading meet the Public Service Electric & Gas (PSE&G) design basis as outlined in Section 7.5.3.1. Items Where Design Precludes Compliance The items categorized under this heading are presently installed, but, by nature of the present design, may not meet the recommendations in the Guide, such as environmental and seismic qualifications. These items are generic to Westinghouse plants. Items Which Are Being Replaced/Added The items categorized under this heading deviate from one or more recommendations in the Guide. These items will be replaced with devices modified to meet the appropriate recommendations. Replacement/installation/ modification for each item will be made to: 1. Meet requirements imposed by other documents such as NUREG-0588 and NUREG-0737. 2. Meet the recommendations of Regulatory Guide 1.97. Items Which Are Not Being Replaced The items categorized under this heading are presently installed, but deviate from one or more recommendations of the Guide. This is based on: 1. Devices located in non-harsh environment that require qualification review in accordance with NUREG-0588 for benign environments which will be completed by June 30, 1982. 7.5-12 SGS-UFSAR Revision 6 February 15, 1987 * * *
- 2. Devices located in a harsh environment that are not utilized in accident emergency instructions for operators to maintain plant safety. 3. Devices currently meeting Technical Specification requirements but the specified ranges do not meet the recommendations in Regulatory Guide 1. 97. Items Not Part of Salem Design The items categorized under this heading are not part of the Salem design and are not being installed. Alternate capabilities are available which meet or will meet our requirements and provide adequate information for maintenance of plant safety. 7.5.3.3 Planned Actions Compliance Level 1 N9 action planned. The instrumentation in this compliance level meets the intent of Regulatory Guide 1. 97 in accordance with the criteria specified in Section 7
- 5. 3. 1. Compliance Level 2 No equipment replacement is planned at this time pending resolution of generic problems. Compliance Level 3a Instruments are being replaced or upgraded as a result of prior commitments related to NUREG-0588 and NUREG-0737. The devices will comply with Regulatory Guide 1.97 in accordance with the 7.5-13 SGS-UFSAR Revision 20 May 6, 2003 criteria specified in Section 7.5.3.1 by the dates specified in previous correspondence to the NRC staff. Compliance Level 3b Instruments will be upgraded to meet Regulatory Guide 1.97 in accordance with the criteria specified in Section 7.5.3.1 by June 1, 1983, or as otherwise committed on a case-by-case basis with the NRC. Compliance Level 4a The equipment will be evaluated in accordance with the requirements of the NUREG-0588 benign environment review, and appropriate actions will be taken where required. Compliance Level 4b No action planned. The importance of the device is deemed to be relatively low or insignificant. Compliance Level 4c The existing devices comply with Technical Specification requirements and should not be modified. Compliance Level 5 No action planned. Other provisions exist which negate the need for the instrumentation. All items currently planned to remain unchanged have been evaluated for potential effects on plant safety. This evaluation concludes that plant safety is not affected by the lack of compliance to Regulatory Guide 1.97. SGS-UFSAR Revision 11 July 22, 1991 * * *