BS IEC 61226 pdf download

BS IEC 61226 pdf download Nuclear power plants – Instrumentation and control important to safety – Classification of instrumentation and control functions
1scope
This International Standard establishes a method of classification of the information andcommand functions for nuclear power plants，and the l&C systems and equipment thatprovide those functions，into categories that designate the importance to safety of thefunction.The resulting classification then determines relevant design criteria.
The design criteria are the measures of quality by which the adequacy of each function inrelation to its importance to plant safety is ensured. In this standard, the criteria are those offunctionality，reliability,performance,environmental durability (including seismic) and qualityassurance (QA).
This standard is applicable to all the information and command functions and the instrument-ation and control (l&C) systems and equipment that provide those functions.The functions,systems and equipment under consideration provide automated protection，closed or openloop control and information to the operating staff. They keep the’NPP conditions inside thesafe operating envelope and provide automatic actions，or enable manual actions，thatprevent or mitigate accidents, or that prevent or minimize radioactive releases to the site orwider environment.The l&C functions that fulfil these roles safeguard the health and safety ofthe NPP operators and the public.
This standard follows the general principles given in lAEA safety code NS-R-1 and safetyguide NS-G-1.3, and it defines a structured method of applying the guidance contained inthose codes and standards to the l&C systems that perform functions important to safety in aNPP. This standard should be read in association with the IAEA guides and lEC 61513 inimplementing the requirements of lEC61508 series.
Normative references
The following referenced documents are indispensable for the application of this document.For dated references,only the edition cited applies. For undated references, the latest editionof the referenced document (including any amendments) applies.
IEC 60671:2007，Nuclear power plants – Instrumentation and control systems important tosafety – surveillance testing
IEC 60709，Nuclear power plants – Instrumentation and control systems important to safety -Separation
IEC 60780，Nuclear power plants – Electrical equipment of the safety system – Qualification
IEC 60812,Analysis techniques for system reliability – Procedure for failure mode and effectsanalysis (FMEA)
IEC 60880:2006，Nuclear power plants – Instrumentation and control systems important tosafety – Software aspects for computer-based systems performing category A functions
lEc 60964,Nuclear power plants – Control rooms – Design
IEC 60965, Supplementary control points for reactor shutdown without access to the main control room
IEC 60980, Recommended practices for seismic qualification of electrical equipment of the safety system for nuclear generating stations
IEC 60987, Nuclear power plants – Instrumentation and control important to safety – Hardware design requirements for computer-based systems
IEC 61 000-4 (all parts), Electromagnetic compatibility (EMC) – Part 4: Testing and measurement techniques
IEC 61 000-6-2, Electromagnetic compatibility (EMC) – Part 6-2: Generic standards – Immunity for industrial environments