IEEE Std 308-2020 pdf free.IEEE Standard Criteria for Class 1E Power Systems for Nuclear Power Generating Stations.
1.3 Word usage
The word shall indicates mandatory requirements strictly to be followed in order to conform to the standard and from which no deviation is permitted (shall equals is required to).
The word should indicates that among several possibilities one is recommended as particularly suitable, without mentioning or excluding others; or that a certain course of action is preferred but not necessarily required (should equals is recommended that).
The word may is used to indicate a course of action permissible within the limits of the standard (may equals is permitted to).
The word can is used for statements of possibility and capability, whether material, physical, or causal (can equals is able to).
2. Normative references
The following referenced documents are indispensable for the application of this document (i.e, they must be understood and used, so each referenced document is cited in text and its relationship to this document is explained). For dated references, only the edition cited applies. For undated references, the latest edition ofthe referenced document (including any amendments or corrigenda) applies.
ASME NQA-1, Quality Assurance Requirements for Nuclear Facilities Applications. Code of Federal Regulations Title 10 Part 100(10 CFR 100), Reactor Site Criteria.
IEC/IEEE 60780-323， IEC/IEEE Intermational Standard- Nuclear Facilities- Electrical Equipment Important to Safety- Qualification.
IEEE Std 7-4.3.2TM, IEEE Standard Criteria for Programmable Digital Devices in Safety Systems of Nuclear Power Generating Stations.
division: The designation applied to a given system or set of components that enables the establishment and maintenance of physical, electrical, and functional independence from other redundant sets of components.
documentation Any wriflen or pictorial infurmation describing, defining, specifying, reporting, or certit’ing activities, requirements. procedures, or results.
engineered safety features: Features of a unit, other than reactor trip or features used only for normal operation. that are provided to prevent, limit, or mitigate the release of radioactive material.
eccue features: The electrical and mechanical equipment and interconnections that perfiirm a function, associated directly or indirectly with a safety function, upon receipt of a signal from the sense and command features. The scope of the execute features extends from the sense and command features output to and including the actuated equipment-to-process coupling.
independence: The state in which no mechanism exists by which any single design basis event can cause redundant equipment to be inoperable.
isolating device: A device in a circuit that prevents malfunction in one section of a circuit from causing unacceptable influences in other sections of the circuit or in other circuits.
load group: An arrangement of buses, transtbrmers, switching equipment, and loads tCd from a common power supply within a division.
module: Any assembly of interconnected components that constitutes an identifiable device, instrument, or piece of equipment. A module can be disconnected, removed as a unit, and replaced with a spare unit.IEEE Std 308 pdf download.