The object of this standard is to describe and interpret various terms considered to be of basic importance to concepts and practical application in the design and evaluation of electromagnetically compatible systems. In addition, attention is drawn to the distinction between electromagnetic compatibility (EMC) tests carried out in a standardized Set-up and those carried out at the location where a device (equipment or system) is installed (in situ tests).
The terms and their definitions are given in Clause 2, with reference to chapter 161 of the IEV [1]. The application of the terms is described in Clause 3 and an interpretation of their definitions is presented in the annexes.
Note: The figures in square brackets indicate the references listed in Annex C.
2 Definition of Terms
The terms of importance in the context of this standard are defined below. Each definition is followed by its IEV number when it is identical with the definition (and any note accompanying it) given in [1]. Where it differs, the IEV number is followed by "/A", or it is indicated that the term has not been defined in IEC 60050(161).
The terms and their definitions can be divided into three groups:
a) Basic terms, for exampie electromagnetic compatibility, emission, immunity and level;
b) Combined terms, which combine basic terms, for example emission level, compatibility level and immunity limit.
c) Interrelated terms, which interrelate combined terms, for example emission margin and compatibility margin.
2.1 Basic Terms
electromagnetic environment (161-01-01)
the totality of electromagnetic phenomena existing at a given location
Note/A: In general, this totality is time dependent and its description may need a statistical approach.
electromagnetic disturbance (161-01-05)
any electromagnetic phenomenon which may degrade the performance of a device, equipment or system, or adversely affect living or inert matter
Note: An electromagnetic disturbance may be an electromagnetic noise, an unwanted signal or a change in the propagation medium itself.
electromagnetic interference (EMI) (161-01-06)
degradation of the performance of a device, equipment or system caused by an electromagnetic disturbance
Note/A: Disturbance and interference are cause and effect respectively.
electromagnetic compatibility (EMC) (161-01-07)
the ability of an equipment or system to function satisfactorily in its electromagnetic environment without introducing intolerable electromagnetic disturbances to anything in that environment
(electromagnetic) emission (161-01-08)
the phenomenon by which electromagnetic energy emanates from a source
degradation (of performance) (161-01-19)
an undesired departure in the operational performance of any device, equipment or system from its intended performance
Note: The term "degradation" can apply to temporary or permanent failure.
immunity (to a disturbance) (161-01-20)
the ability of a device, equipment or system to perform without degradation in the presence of an electromagnetic disturbance
(electromagnetic) susceptibility (161-01-21)
The inability of a device, equipment or system to perform without degradation in the presence of an electromagnetic disturbance
Note: Susceptibility is a lack of immunity
level (of a quantity) (not defined in IEC 60050(161)
the magnitude of a quantity evaluated in a specified manner
Note: The level of a quantity may be expressed in logarithmic units, for example decibels with respect to a reference value.
2.2 Combined Terms
emission level (of a disturbing source) (161-03-11)
the level of a given electromagnetic disturbance emitted from a particular device, equipment or system, measured in a specified way
emission limit (from a disturbing source) (161-03-12/A)
the maximum permissible emission level
immunity level (161-03-14/A)
the maximum level of a given electromagnetic disturbance, incident in a specified way on a particular device, equipment or system, at which no degradation of operation occurs
immunity limit (161-03-15/A)
the minimum required immunity level
disturbance level (not defined in IEC 60050(161)
The level of a given electromagnetic disturbance, measured in a specified way
the ratio of the immunity limit to the emission limit
Note/A: the compatibility margin is the product of the emission margin and the immunity margin General note: If the levels are expressed in dB(...), in the above margin definitions "difference" should be read instead of "ratio" and "sum" instead of "product".
Foreword II IEC Foreword III Introduction IV 1 Scope 2 Definition of Terms 3 Application of EMC Terms and Definitions Annex A (Normative) Interpretation of EMC Terms and Definitions Annex B (Normative) Standardized and In-situ Tests Annex C (Informative) References
1 Scope
The object of this standard is to describe and interpret various terms considered to be of basic importance to concepts and practical application in the design and evaluation of electromagnetically compatible systems. In addition, attention is drawn to the distinction between electromagnetic compatibility (EMC) tests carried out in a standardized Set-up and those carried out at the location where a device (equipment or system) is installed (in situ tests).
The terms and their definitions are given in Clause 2, with reference to chapter 161 of the IEV [1]. The application of the terms is described in Clause 3 and an interpretation of their definitions is presented in the annexes.
Note: The figures in square brackets indicate the references listed in Annex C.
2 Definition of Terms
The terms of importance in the context of this standard are defined below. Each definition is followed by its IEV number when it is identical with the definition (and any note accompanying it) given in [1]. Where it differs, the IEV number is followed by "/A", or it is indicated that the term has not been defined in IEC 60050(161).
The terms and their definitions can be divided into three groups:
a) Basic terms, for exampie electromagnetic compatibility, emission, immunity and level;
b) Combined terms, which combine basic terms, for example emission level, compatibility level and immunity limit.
c) Interrelated terms, which interrelate combined terms, for example emission margin and compatibility margin.
2.1 Basic Terms
electromagnetic environment (161-01-01)
the totality of electromagnetic phenomena existing at a given location
Note/A: In general, this totality is time dependent and its description may need a statistical approach.
electromagnetic disturbance (161-01-05)
any electromagnetic phenomenon which may degrade the performance of a device, equipment or system, or adversely affect living or inert matter
Note: An electromagnetic disturbance may be an electromagnetic noise, an unwanted signal or a change in the propagation medium itself.
electromagnetic interference (EMI) (161-01-06)
degradation of the performance of a device, equipment or system caused by an electromagnetic disturbance
Note/A: Disturbance and interference are cause and effect respectively.
electromagnetic compatibility (EMC) (161-01-07)
the ability of an equipment or system to function satisfactorily in its electromagnetic environment without introducing intolerable electromagnetic disturbances to anything in that environment
(electromagnetic) emission (161-01-08)
the phenomenon by which electromagnetic energy emanates from a source
degradation (of performance) (161-01-19)
an undesired departure in the operational performance of any device, equipment or system from its intended performance
Note: The term "degradation" can apply to temporary or permanent failure.
immunity (to a disturbance) (161-01-20)
the ability of a device, equipment or system to perform without degradation in the presence of an electromagnetic disturbance
(electromagnetic) susceptibility (161-01-21)
The inability of a device, equipment or system to perform without degradation in the presence of an electromagnetic disturbance
Note: Susceptibility is a lack of immunity
level (of a quantity) (not defined in IEC 60050(161)
the magnitude of a quantity evaluated in a specified manner
Note: The level of a quantity may be expressed in logarithmic units, for example decibels with respect to a reference value.
2.2 Combined Terms
emission level (of a disturbing source) (161-03-11)
the level of a given electromagnetic disturbance emitted from a particular device, equipment or system, measured in a specified way
emission limit (from a disturbing source) (161-03-12/A)
the maximum permissible emission level
immunity level (161-03-14/A)
the maximum level of a given electromagnetic disturbance, incident in a specified way on a particular device, equipment or system, at which no degradation of operation occurs
immunity limit (161-03-15/A)
the minimum required immunity level
disturbance level (not defined in IEC 60050(161)
The level of a given electromagnetic disturbance, measured in a specified way
(electromagnetic) compatibility level (161-03-10/A)
the specified disturbance level at which an acceptable, high probability of electromagnetic compatibility should exist
2.3 Interrelated Terms
emission margin (161-03-13/A)
the ratio of the electromagnetic compatibility level to the emission limit
immunity margin (161-03-16/A)
The ratio of the immunity limit to the electromagnetic compatibility level
(electromagnetic) compatibility margin (161-03-17/A)
the ratio of the immunity limit to the emission limit
Note/A: the compatibility margin is the product of the emission margin and the immunity margin General note: If the levels are expressed in dB(...), in the above margin definitions "difference" should be read instead of "ratio" and "sum" instead of "product".
Contents of GB/T 17624.1-1998
Foreword II
IEC Foreword III
Introduction IV
1 Scope
2 Definition of Terms
3 Application of EMC Terms and Definitions
Annex A (Normative) Interpretation of EMC Terms and Definitions
Annex B (Normative) Standardized and In-situ Tests
Annex C (Informative) References
