IEC 61000-4-5:2014

IEC 61000-4-5 ®
Edition 3.0 2014-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
BASIC EMC PUBLICATION
PUBLICATION FONDAMENTALE EN CEM
Electromagnetic compatibility (EMC) –
Part 4-5: Testing and measurement techniques – Surge immunity test

Compatibilité électromagnétique (CEM) –
Partie 4-5: Techniques d'essai et de mesure – Essai d'immunité aux ondes de
choc
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IEC 61000-4-5 ®
Edition 3.0 2014-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
BASIC EMC PUBLICATION
PUBLICATION FONDAMENTALE EN CEM

Electromagnetic compatibility (EMC) –

Part 4-5: Testing and measurement techniques – Surge immunity test

Compatibilité électromagnétique (CEM) –

Partie 4-5: Techniques d'essai et de mesure – Essai d'immunité aux ondes de

choc
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX XC
ICS 33.100.20 ISBN 978-2-8322-1532-6

– 2 – IEC 61000-4-5:2014 © IEC 2014
CONTENTS
FOREWORD . 6
INTRODUCTION . 8
1 Scope and object . 9
2 Normative references . 9
3 Terms, definitions and abbreviations . 10
3.1 Terms and definitions . 10
3.2 Abbreviations . 13
4 General . 13
4.1 Power system switching transients . 13
4.2 Lightning transients . 14
4.3 Simulation of the transients . 14
5 Test levels . 14
6 Test instrumentation . 15
6.1 General . 15
6.2 1,2/50 µs combination wave generator . 15
6.2.1 General . 15
6.2.2 Performance characteristics of the generator . 16
6.2.3 Calibration of the generator . 18
6.3 Coupling/decoupling networks . 19
6.3.1 General . 19
6.3.2 Coupling/decoupling networks for a.c./d.c. power port rated up
to 200 A per line . 20
6.3.3 Coupling/decoupling networks for interconnection lines . 24
6.4 Calibration of coupling/decoupling networks . 27
6.4.1 General . 27
6.4.2 Calibration of CDNs for a.c./d.c. power port rated up to 200 A
per line . 27
6.4.3 Calibration of CDNs for interconnection lines . 28
7 Test setup . 30
7.1 Test equipment . 30
7.2 Verification of the test instrumentation . 31
7.3 Test setup for surges applied to EUT power ports . 31
7.4 Test setup for surges applied to unshielded unsymmetrical
interconnection lines . 32
7.5 Test setup for surges applied to unshielded symmetrical interconnection
lines . 32
7.6 Test setup for surges applied to shielded lines . 32
8 Test procedure . 33
8.1 General . 33
8.2 Laboratory reference conditions . 34
8.2.1 Climatic conditions . 34
8.2.2 Electromagnetic conditions . 34
8.3 Execution of the test . 34
9 Evaluation of test results . 35
10 Test report . 35

Annex A (normative) Surge testing for unshielded outdoor symmetrical communication
lines intended to interconnect to widely dispersed systems . 37
A.1 General . 37
A.2 10/700 µs combination wave generator . 37
A.2.1 Characteristics of the generator . 37
A.2.2 Performances of the generator . 38
A.2.3 Calibration of the generator . 40
A.3 Coupling/decoupling networks . 40
A.3.1 General . 40
A.3.2 Coupling/decoupling networks for outdoor communication

lines . 41
A.4 Calibration of coupling/decoupling networks . 41
A.5 Test setup for surges applied to outdoor unshielded symmetrical
communication lines . 42
Annex B (informative) Selection of generators and test levels . 44
B.1 General . 44
B.2 The classification of environments . 44
B.3 The definition of port types. 44
B.4 Generators and surge types . 45
B.5 Tables. 45
Annex C (informative) Explanatory notes . 47
C.1 Different source impedance . 47
C.2 Application of the tests . 47
C.2.1 Equipment level immunity . 47
C.2.2 System level immunity . 47
C.3 Installation classification . 48
C.4 Minimum immunity level of ports connected to the a.c./d.c. mains supply . 49
C.5 Equipment level immunity of ports connected to interconnection lines . 49
Annex D (informative) Considerations for achieving immunity for equipment
connected to low voltage power distribution systems . 51
Annex E (informative) Mathematical modelling of surge waveforms . 53
E.1 General . 53
E.2 Normalized time domain voltage surge (1,2/50 µs) . 54
E.3 Normalized time domain current surge (8/20 µs) . 55
E.4 Normalized time domain voltage surge (10/700 µs) . 57
E.5 Normalized time domain current surge (5/320 µs) . 59
Annex F (informative) Measurement uncertainty (MU) considerations . 62
F.1 Legend . 62
F.2 General . 62
F.3 Uncertainty contributors to the surge measurement uncertainty . 63
F.4 Uncertainty of surge calibration . 63
F.4.1 General . 63
F.4.2 Front time of the surge open-circuit voltage . 63
F.4.3 Peak of the surge open-circuit voltage . 65
F.4.4 Duration of the surge open-circuit voltage . 66
F.4.5 Further MU contributions to time and amplitude
measurements . 67
F.4.6 Rise time distortion due to the limited bandwidth of the

measuring system . 67

– 4 – IEC 61000-4-5:2014 © IEC 2014
F.4.7 Impulse peak and width distortion due to the limited
bandwidth of the measuring system . 68
F.5 Application of uncertainties in the surge generator compliance criterion . 69
Annex G (informative) Method of calibration of impulse measuring systems . 70
G.1 General . 70
G.2 Estimation of measuring system response using the convolution integral . 70
G.3 Impulse measuring system for open-circuit voltage (1,2/50 µs, 10/700 µs) . 71
G.4 Impulse measuring system for short-circuit current (8/20 µs, 5/320 µs) . 71
Annex H (informative) Coupling/decoupling surges to lines rated above 200 A . 73
H.1 General . 73
H.2 Considerations of coupling and decoupling . 73
H.3 Additional precautions . 74
Bibliography . 75

Figure 1 – Simplified circuit diagram of the combination wave generator . 16
Figure 2 – Waveform of open-circuit voltage (1,2/50 µs) at the output of the generator
with no CDN connected . 17
Figure 3 – Waveform of short-circuit current (8/20 µs) at the output of the generator
with no CDN connected . 18
Figure 4 – Selection of coupling/decoupling method. 20
Figure 5 – Example of coupling network and decoupling network for capacitive
coupling on a.c./d.c. lines line-to-line coupling . 22
Figure 6 – Example of coupling network and decoupling network for capacitive
coupling on a.c./d.c. lines: line-to-ground coupling . 23
Figure 7 – Example of coupling network and decoupling network for capacitive
coupling on a.c. lines (3 phases): line L2-to-line L3 coupling . 23
Figure 8 – Example of coupling network and decoupling network for capacitive
coupling on a.c. lines (3 phases): line L3-to-ground coupling . 24
Figure 9 – Example of coupling network and decoupling network for unshielded
unsymmetrical interconnection lines: line-to-line and line-to-ground coupling . 25
Figure 10 – Example of coupling and decoupling network for unshielded symmetrical
interconnection lines: lines-to-ground coupling . 26
Figure 11 – Example of coupling and decoupling network for unshielded symmetrical
interconnection lines: lines-to-ground coupling via capacitors . 27
Figure 12 – Example of test setup for surges applied to shielded lines . 33
Figure A.1 – Simplified circuit diagram of the combination wave generator (10/700 µs
– 5/320 µs) . 38
Figure A.2 – Waveform of open-circuit voltage (10/700 µs) . 39
Figure A.3 – Waveform of the 5/320 µs short-circuit current waveform . 39
Figure A.4 – Example of test setup for unshielded outdoor symmetrical communication
lines: lines-to-ground coupling, coupling via gas arrestors (primary protection fitted) . 41
Figure E.1 – Voltage surge (1,2/50 µs): width time response T . 54
w
Figure E.2 – Voltage surge (1,2/50 µs): rise time response T . 55
Figure E.3 – Voltage surge (1,2/50 µs): spectral response with ∆f = 3,333 kHz . 55
Figure E.4 – Current surge (8/20 µs): width time response T . 56
w
Figure E.5 – Current surge (8/20 µs): rise time response T . 57
r
Figure E.6 – Current surge (8/20 µs): spectral response with ∆f = 10 kHz . 57

Figure E.7 – Voltage surge (10/700 µs): width time response T . 58
w
Figure E.8 – Voltage surge (10/700 µs): rise time response T . 59
Figure E.9 – Voltage surge (10/700 µs): spectral response with ∆f = 0,2 kHz . 59
Figure E.10 – Current surge (5/320 µs): width time response T . 60
w
Figure E.11 – Current surge (5/320 µs): rise time response T . 61
r
Figure E.12 – Current surge (5/320 µs): spectral response with ∆f = 0,4 kHz . 61
Figure G.1 – Simplified circuit diagram of the current step generator . 72

Table 1 – Test levels. 15
Table 2 – Definitions of the waveform parameters 1,2/50 µs and 8/20 µs . 17
Table 3 – Relationship between peak open-circuit voltage and peak short-circuit
current . 17
Table 4 – Voltage waveform specification at the EUT port of the CDN . 21
Table 5 – Current waveform specification at the EUT port of the CDN. 21
Table 6 – Relationship between peak open-circuit voltage and peak short-circuit
current at the EUT port of the CDN . 22
Table 7 – Summary of calibration process for CDNs for unsymmetrical interconnection

lines . 28
Table 8 – Surge waveform specifications at the EUT port of the CDN for unsymmetrical
interconnection lines . 29
Table 9 – Summary of calibration process for CDNs for symmetrical interconnection
lines . 30
Table 10 – Surge waveform specifications at the EUT port of the CDN for symmetrical

interconnection lines . 30
Table A.1 – Definitions of the waveform parameters 10/700 µs and 5/320 µs . 39
Table A.2 – Relationship between peak open-circuit voltage and peak short-circuit
current . 40
Table A.3 – Summary of calibration process for CDNs for unshielded outdoor
symmetrical communication lines . 42
Table A.4 – Surge waveform specifications at the EUT port of the CDN for unshielded
outdoor symmetrical communication lines . 42
Table B.1 – Power ports: selection of the test levels (depending on the installation
class) . 45
Table B.2 – Circuits/lines: selection of the test levels (depending on the installation
class) . 46
Table F.1 – Example of uncertainty budget for surge open-circuit voltage front time
(T ) . 64
fV
Table F.2 – Example of uncertainty budget for surge open-circuit voltage peak value

(V ) . 65
P
Table F.3 – Example of uncertainty budget for surge open-circuit voltage duration (T ) . 66
d
Table F.4 – α factor, Equation (F.5), of different unidirectional impulse responses
corresponding to the same bandwidth of the system B . 68
Table F.5 – β factor, Equation (F.9), of the standard surge waveforms . 69
Table H.1 – Recommended inductance values for decoupling lines (> 200 A) . 73

– 6 – IEC 61000-4-5:2014 © IEC 2014
COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
____________
ELECTROMAGNETIC COMPATIBILITY (EMC) –

Part 4-5: Testing and measurement techniques –
Surge immunity test
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61000-4-5 has been prepared by subcommittee 77B: High
frequency phenomena, of IEC technical Committee 77: Electromagnetic compatibility.
It forms Part 4-5 of IEC 61000. It has the status of a basic EMC publication in accordance
with IEC Guide 107.
This third edition cancels and replaces the second edition published in 2005, and constitutes
a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) new Annex E on mathematical modelling of surge waveforms;
b) new Annex F on measurement uncertainty;
c) new Annex G on method of calibration of impulse measuring systems;

d) new Annex H on coupling/decoupling surges to lines rated above 200 A;
e) moreover while surge test for ports connected to outside telecommunication lines was
addressed in 6.2 of the second edition (IEC 61000-4-5:2005), in this third edition
(IEC 61000-4-5:2014) the normative Annex A is fully dedicated to this topic. In particular it
gives the specifications of the 10/700 µs combined wave generator.
The text of this standard is based on the following documents:
FDIS Report on voting
77B/711/FDIS 77B/715/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 61000 series, published under the general title Electromagnetic
compatibility (EMC), can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
– 8 – IEC 61000-4-5:2014 © IEC 2014
INTRODUCTION
IEC 61000 is published in separate parts according to the following structure:
Part 1: General
General considerations (introduction, fundamental principles)
Definitions, terminology
Part 2: Environment
Description of the environment
Classification of the environment
Compatibility levels
Part 3: Limits
Emission limits
Immunity limits (insofar as they do not fall under the responsibility of the product
committees)
Part 4: Testing and measurement techniques
Measurement techniques
Testing techniques
Part 5: Installation and mitigation guidelines
Installation guidelines
Mitigation methods and devices
Part 6: Generic standards
Part 9: Miscellaneous
Each part is further subdivided into several parts, published either as international standards
or as technical specifications or technical reports, some of which have already been published
as sections. Others will be published with the part number followed by a dash and a second
number identifying the subdivision (example: IEC 61000-6-1).
This part is an International Standard which gives immunity requirements and test procedures
related to surge voltages and surge currents.

ELECTROMAGNETIC COMPATIBILITY (EMC) –

Part 4-5: Testing and measurement techniques –
Surge immunity test
1 Scope and object
This part of IEC 61000 relates to the immunity requirements, test methods, and range of
recommended test levels for equipment with regard to unidirectional surges caused by over-
voltages from switching and lightning transients. Several test levels are defined which relate
to different environment and installation conditions. These requirements are developed for
and are applicable to electrical and electronic equipment.
The object of this standard is to establish a common reference for evaluating the immunity of
electrical and electronic equipment when subjected to surges. The test method documented in
this part of IEC 61000 describes a consistent method to assess the immunity of an equipment
or system against a defined phenomenon.
NOTE As described in IEC Guide 107, this is a basic EMC publication for use by product committees of the IEC.
As also stated in Guide 107, the IEC product committees are responsible for determining whether this immunity
test standard is applied or not, and if applied, they are responsible for determining the appropriate test levels and
performance criteria. TC 77 and its sub-committees are prepared to co-operate with product committees in the
evaluation of the value of particular immunity test levels for their products.
This standard defines:
– a range of test levels;
– test equipment;
– test setups;
– test procedures.
The task of the described laboratory test is to find the reaction of the equipment under test
(EUT) under specified operational conditions to surge voltages caused by switching and
lightning effects.
It is not intended to test the capability of the EUT's insulation to withstand high-voltage stress.
Direct injections of lightning currents, i.e. direct lightning strikes, are not considered in this
standard.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60050 (all parts), International Electrotechnical Vocabulary (IEV) (available at
www.electropedia.org)
– 10 – IEC 61000-4-5:2014 © IEC 2014
3 Terms, definitions and abbreviations
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60050 as well as
the following apply.
3.1.1
avalanche device
diode, gas tube arrestor, or other component that is designed to break down and conduct at a
specified voltage
3.1.2
calibration
set of operations which establishes, by reference to standards, the relationship which exists,
under specified conditions, between an indication and a result of a measurement
Note 1 to entry: This term is based on the "uncertainty" approach.
Note 2 to entry: The relationship between the indications and the results of measurement can be expressed, in
principle, by a calibration diagram.
[SOURCE: IEC 60050-311:2001, 311-01-09]
3.1.3
clamping device
diode, varistor or other component that is designed to prevent an applied voltage from
exceeding a specified value
3.1.4
combination wave generator
CWG
generator with 1,2/50 µs or 10/700 µs open-circuit voltage waveform and respectively 8/20 µs
or 5/320 µs short-circuit current waveform
3.1.5
coupling network
CN
electrical circuit for the purpose of transferring energy from one circuit to another
3.1.6
coupling/decoupling network
CDN
combination of a coupling network and a decoupling network
3.1.7
decoupling network
DN
electrical circuit for the purpose of preventing surges applied to the EUT from affecting other
devices, equipment or systems which are not under test
3.1.8
duration
3.1.8.1
duration
T
d
time interval between the instant at which the surge voltage rises to 0,5 of its
peak value, and then falls to 0,5 of its peak value (T )
w
T = T
d w
SEE: Figures 2 and A.2
3.1.8.2
duration
T
d
virtual parameter defined as the time interval between the instant
at which the surge current rises to 0,5 of its peak value, and then falls to 0,5 of its peak value
(T ), multiplied by 1,18
w
T = 1,18 × T
d w
SEE: Figure 3.
3.1.8.3
duration
T
d
time interval between the instant at which the surge current rises
to 0,5 of its peak value, and then falls to 0,5 of its peak value (T )
w
T = T
d w
SEE: Figure A.3.
3.1.9
effective output impedance
ratio of the peak open-circuit voltage to the peak short-circuit current at the
same output port
3.1.10
electrical installation
assembly of associated electrical equipment having co-ordinated characteristics to fulfil
purposes
[SOURCE: IEC 60050-826:2004, 826-10-01]
3.1.11
front time
3.1.11.1
front time
T
f
virtual parameter defined as 1,67 times the interval T between the instants
when the impulse is 30 % and 90 % of the peak value
SEE: Figures 2 and A.2.
3.1.11.2
front time
T
f
virtual parameter defined as 1,25 times the interval T between the instants
r
when the impulse is 10 % and 90 % of the peak value
SEE: Figures 3 and A.3.
3.1.12
high-speed communication lines
input/output lines which operate at transmission frequencies above 100 kHz

– 12 – IEC 61000-4-5:2014 © IEC 2014
3.1.13
immunity
ability of a device, equipment or system to perform without degradation in the presence of an
electromagnetic disturbance
[SOURCE: IEC 60050-161:1990, 161-01-20]
3.1.14
interconnection lines
I/O lines (input/output lines) and/or communication lines and/or low voltage d.c. input/output
lines (≤ 60 V), where secondary circuits (isolated from the a.c. mains supply) are not subject
to transient over-voltages (i.e. reliably-grounded, capacitively-filtered d.c. secondary circuits
where the peak-to-peak ripple is less than 10 % of the d.c. component)
3.1.15
power port
port, at which the conductor or cable carrying the primary electrical power needed for the
operation (functioning) of an apparatus or associated apparatus is connected to the apparatus
3.1.16
primary protection
means by which the majority of stressful energy is prevented from propagating beyond a
designated interface
3.1.17
reference ground
part of the Earth considered as conductive, the electrical potential of which is conventionally
taken as zero, being outside the zone of influence of any earthing (grounding) arrangement
[SOURCE: IEC 60050-195:1998, 195-01-01]
3.1.18
rise time
T
r
interval of time between the instants at which the instantaneous value of an impulse first
reaches 10 % value and then 90 % value
SEE: Figures 3 and A.3.
[SOURCE: IEC 60050-161:1990, 161-02-05, modified – the content of the note has been
included in the definition and “pulse” has been changed to “impulse”.]
3.1.19
secondary protection
means by which the let-through energy from primary protection is suppressed
Note 1 to entry: It may be a special device or an inherent characteristic of the EUT.
3.1.20
surge
transient wave of electrical current, voltage or power propagating along a line or a circuit and
characterized by a rapid increase followed by a slower decrease
[SOURCE: IEC 60050-161:1990, 161-08-11, modified – “surge” here applies to voltage,
current and power]
3.1.21
symmetrical lines
pair of symmetrically driven conductors with a conversion loss from differential to common
mode of greater than 20 dB
3.1.22
system
set of interdependent elements constituted to achieve a given objective by performing a
specified function
Note 1 to entry: The system is considered to be separated from the environment and other external systems by an
imaginary surface which cuts the links between them and the considered system. Through these links, the system
is affected by the environment, is acted upon by the external systems, or acts itself on the environment or the
external systems.
3.1.23
transient, adjective and noun
pertaining to or designating a phenomenon or a quantity which varies between two
consecutive steady states during a time interval short compared to the time scale of interest
[SOURCE: IEC 60050-161:1990, 161-02-01]
3.1.24
verification
set of operations which is used to check the test equipment system (e.g. the test generator
and its interconnecting cables) to demonstrate that the test system is functioning
Note 1 to entry: The methods used for verification may be different from those used for calibration.
Note 2 to entry: For the purposes of this basic EMC standard this definition is different from the definition given in
IEC 60050-311:2001, 311-01-13.
3.2 Abbreviations
AE Auxiliary equipment
CD Coupling device
CDN Coupling/decoupling network
CLD Clamping device
CN Coupling network
CWG Combination wave generator
DN Decoupling network
EFT/B Electrical fast transient/burst
EMC Electromagnetic compatibility
ESD Electrostatic discharge
EUT Equipment under test
GDT Gas discharge tube
MU Measurement uncertainty
PE Protective earth
SPD Surge protective device
4 General
4.1 Power system switching transients
Power system switching transients can be separated into transients associated with:

– 14 – IEC 61000-4-5:2014 © IEC 2014
a) major power system switching disturbances, such as capacitor bank switching;
b) minor local switching activity or load changes in the power distribution system;
c) resonating circuits associated with switching devices, e.g. thyristors, transistors;
d) various system faults, such as short-circuits and arcing faults to the grounding system of
the installation.
4.2 Lightning transients
The major mechanisms by which lightning produces surge voltages are the following:
a) direct lightning stroke to an external (outdoor) circuit injecting high currents that produce
voltages by either flowing through ground resistance or flowing through the impedance of
the external circuit;
b) indirect lightning stroke (i.e. a stroke between or within clouds or to nearby objects which
produces electromagnetic fields) that induces voltages/currents on the conductors outside
and/or inside a building;
c) lightning ground current flow resulting from nearby direct-to-earth discharges coupling into
the common ground pa
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