IEC 63147:2017 pdf download

IEC 63147:2017 pdf download.Criteria for accident monitoring instrumentation for nuclear power generating stations
1. Overview
1.1 Scope
This standard contains the functional and design criteria for accident monitoring instrumentation for new plant designs and nuclear power generating stations desiring to perform design modifications.
1.2 Purpose
The purpose of this standard is to establish selection, design, performance, qualification, and display criteria for accident monitoring instrumentation for anticipated operational occurrences, design basis events, and severe accidents.
1.3 Application
This standard applies to accident monitoring instrumentation intended for use during the following operations:
– As required for planned operator action related to accident mitigation
3. Definitions
For the purposes of this document, the following terms and definitions apply. The IEEE Standards Dictionary Online should be consulted for terms not defined in this clause. 7 accident analysis licensing basis: The portions of the licensing basis documentation that describe the design basis events (including anticipated operational occurrences), the thermal-hydraulic response of the nuclear power generating station, and the subsequent response of the safety systems. accident management personnel: The personnel authorized to make command and control decisions during an accident. accuracy: A measure of the degree by which the actual output of a device approximates the output of an ideal device nominally performing the same function. anticipated operational occurrence (AOO): An operational process deviating from normal operation which is expected to occur at least once during the operating lifetime of a facility but which, in view of appropriate design provisions, does not cause any significant damage to items important to safety or lead to accident conditions. auxiliary supporting features: Systems or components that provide services (such as cooling, lubrication, and energy supply) required for the safety systems to accomplish their safety functions.common cause failure: Failure of two or more structures, systems, or components due to a shared root cause. contingency actions: Alternative actions taken to address unexpected responses of the plant or conditions beyond its licensing basis (e.g., actions taken for multiple equipment failures). current value: That magnitude of a variable that is associated with the present time and is available for display within the response time limits of an information display channel. design basis event (DBE): Postulated events specified by the safety analysis for the station to establish the acceptable performance requirements of the structures and systems. design extension conditions (DEC): Postulated accident conditions that are not considered for design basis accidents, but that are considered in the design process of the facility in accordance with best estimate methodology, and for which releases of radioactive material are kept within acceptable regulatory limits. NOTE—Design extension conditions include conditions in events without significant fuel degradation and conditions with core melting. Severe accidents are included in design extension conditions. 8 display channel: An arrangement of electrical and mechanical components or modules, or both, from the measured process variable to the display device as required to sense, process, and display conditions within the nuclear power generating station. NOTE—See Figure 1. display segment: The electrical components or modules in an information display channel that receive the processing electronics output and process the signal for input to the applicable display device, such as a video display unit (VDU) or indicator (IND). The display segment may include data validation algorithms, storage of digital display graphics, and analog or digital display devices. power sources: The electrical and mechanical equipment and their interconnections necessary to generate or convert power. NOTE—Power source and power supply are considered interchangeable in this standard. precision: The degree of mutual agreement between individual measurements, namely repeatability and reproducibility. processing segment: The electrical components or modules in an information display channel that receive the sensing segment outputs and perform various conversions and compensation on the sensed signal. The processing electronics may include sensor power supply, analog-to-digital (A/D) conversion, signal compensation, signal validation, electrical to engineering unit conversion, digital-to-analog (D/A) conversion, and electrical isolation devices for signal interfacing between safety systems and other systems.