BS EN IEC 60709:2019 pdf download

BS EN IEC 60709:2019 pdf download.Nuclear power plants – Instrumentation, control and electrical systems important to safety – Separation.
ISOURCE: IAEA Safety Glossary, edition 20161
design extension condition
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 lim,ts Design extension conditions comprise conditions in events without significant fuel degradation and conditions In events with melting of the reactor core
ISOURCE IAEA Safety Glossary, edition 20161
3.7
distance
placement of the components being protected sufficiently far away from one another so as to ensure that they cannot be simultaneously damaged by the considered event
3.8
diversity
presence of two or more independent (redundant) systems or components to perform an identified function, where the different systems or components have different attributes so as to reduce the possibility of common cause failure, including common mode failure
ISOURCE: IAEA Safety Glossary, edition 20161
3.9
dIvisIon
collection of items, including their interconnections, that form one redundancy of a redundant system or safety group. Divisions may include multiple channels
Note 1 to entry In the context of thu document, •dlvlsiori includes a grv.n system or set of co’nponents that enables the establishment arid maintenance 01 physical, electrical. and functional independence from other redundant sets of components
(SOURCE: IAEA SSG-39, 2016]
3.10
electrical isolation
electrical isolation is used to prevent electrical failures in one system from affecting connected systems. Electrical isolation controls or prevents adverse interactions between equipment and components caused by factors such as electromagnetic interference. electrostatic pickup, short circuits, open circuits grounding, or application of the maximum credible voltage (AC or DC)
(SOURCE: IAEA SSG-34 and SSG-39, 20161
3.11
electromagnetic compatibility
EMC
ability of an equipment or system to function satisfactorily in its electromagnetic environment without introducing intolerable electromagnetic disturbances to anything in that environment
(SOURCE: IEC 60050-161:1990, 161-01-07)
3.12
electromagnetic interference
EMI
degradation of the performance of an equipment, transmission channel or system caused by an electromagnetic disturbance
(SOURCE: IEC 60050-161:1990. 161-01-061
3.13
lnd.p.ndenc.
condition that exists when successful completion of a system’s required functions Is not dependent upon any behaviour including failures and normal operation of another system, or upon any signals, data, or information derived from the other system
Not. Ito entry: lb. loliowing definition is to be found in th. IAEA Safety Glossary, edition 2016 to, independ.nt equipinenr ‘Equipment that possesses both of the following acIeflIUcs. a) The ability to perform its required function Is unaffected by liv. operation or failure of olti.r equipment: b) The ability to perform its required function is unaffected by the occurrence of lie .1f.cts resuitrng from th. initiating event for .tiiclv it is required to function. This IAEA definition ii lwviited to equipment but is consistent with the definition given in title document
3.14
Isolation device
device in a circuit that prevents malfunctions in one section of a circuit from causing unacceptable influences In other sections of the circuit or other circuits
(SoURCE’ IEC 62808’2015, 3.4J
3.15
physical separation
separation by geometry (distance, ortentation, etc.). by appropriate barriers, or by a combination thereof
(SOURCE: IAEA Safety Glossary, edition 20161
3.16
postulated initiating event
PIE
postulated event identified in design as capable of leading to anticipated operational occurrences or accident conditions
(SOURCE. IAEA Safety Glossary, edition 2016)
3.17
redundancy
provision of alternative (identical or diverse) structures, systems and components, so that any single structure. system or component can perform the required function regardless of the state of operation or failure of any other
(SOURCE: IAEA Safety Glossary, edition 201611
3.18
safety group
assembly of equipment designated to perform all actions required for a particular initiating event to ensure that the limits specified In the design basis for anticipated operational occurrences and design basis accidents are not exceeded
(SOURCE: IAEA Safety Glossary, edition 2016).