ISO 7637-1:2015

INTERNATIONAL ISO
STANDARD 7637-1
Third edition
2015-10-01
Road vehicles — Electrical
disturbances from conduction and
coupling —
Part 1:
Definitions and general
considerations
Véhicules routiers — Perturbations électriques par conduction et
par couplage —
Partie 1: Définitions et généralités
Reference number
©
ISO 2015
© ISO 2015, Published in Switzerland
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ii © ISO 2015 – All rights reserved

Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 General aim and practical use of ISO 7637. 4
5 General test conditions . 5
5.1 General . 5
5.2 Test temperature . 5
5.3 Supply voltage . . 6
Annex A (normative) Function performance status classification (FPSC) . 7
Bibliography .10
Foreword
ISO (the International Organization for Standardization) is a worldwide federation of national standards
bodies (ISO member bodies). The work of preparing International Standards is normally carried out
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ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
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Barriers to Trade (TBT) see the following URL: Foreword - Supplementary information.
The committee responsible for this document is ISO/TC 22, Road vehicles, Subcommittee SC 32, Electrical
and electronic components and general system aspects.
This third edition cancels and replaces the second edition (ISO 7637-1:2002), which has been technically
revised. It also incorporates the Amendment ISO 7637-1:2002/Amd 1: 2008.
ISO 7637 consists of the following parts, under the general title Road vehicles — Electrical disturbances
from conduction and coupling:
— Part 1: Definitions and general considerations
— Part 2: Electrical transient conduction along supply lines only
— Part 3: Electrical transient transmission by capacitive and inductive coupling via lines other than supply
lines
The following parts are under preparation:
— Part 4: Electrical transient conduction along shielded high voltage supply lines only
— Part 5: Enhanced definitions and verification methods for harmonization of pulse generators according
to ISO 7637–2 [Technical Report]
Annex A forms an integral part of this part of ISO 7637.
iv © ISO 2015 – All rights reserved

Introduction
Electrical and radio-frequency disturbances occur during normal operation of many items of motor
vehicle equipment. They are generated over a wide frequency range and can be distributed to on-board
electronic devices and systems by conduction, coupling or radiation.
In recent years, an increasing number of electronic devices for controlling, monitoring and displaying a
variety of functions have been introduced into vehicle designs. It is necessary to consider the electrical
and electromagnetic environment in which these devices operate and, in particular, the disturbances
generated in the vehicle electrical system itself. Such disturbances can cause degradation (temporary
malfunction or even permanent damage) of the electronic equipment. Moreover, “worst-case” situations
are usually those resulting from disturbances generated inside the vehicle by, for example, ignition
systems, generator and alternator systems, electric motors and actuators.
Annex A specifies a general method for function performance status classification (FPSC). Typical
severity levels are included in an annex of each of the other parts of ISO 7637.
While narrowband signals generated on or outside the vehicle (by broadcasting and radio-transmitters)
can also affect the performance of electronic devices, and recognizing that protection from such
potential disturbances has to be considered as part of total system certification, these matters are
nevertheless outside the scope of ISO 7637 and are not covered by it.
ISO 11451 and ISO 11452 specify test methods for immunity to radiated disturbances for vehicles
and for components, respectively. ISO 10605 specifies test methods for immunity to electrostatic
discharge (ESD) for vehicle and for components.
INTERNATIONAL STANDARD ISO 7637-1:2015(E)
Road vehicles — Electrical disturbances from conduction
and coupling —
Part 1:
Definitions and general considerations
1 Scope
This part of ISO 7637 defines the basic terms relating to electrical disturbances from conduction and
coupling used in the other parts of ISO 7637. It also gives general information on the whole ISO 7637 series.
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 60050–151, International Electrotechnical Vocabulary — Part 151: Electrical and magnetic devices
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60050–151 and the
following apply.
3.1
artificial network
AN
network inserted in the supply lead or signal/load lead of apparatus to be tested which provides, in a
given frequency range, a specified load impedance for the measurement of disturbance voltages and
which can isolate the apparatus from the supply or signal sources/loads in that frequency range
Note 1 to entry: Network inserted in the d.c. power lines of the DUT which provides, in a given frequency range, a
specified load impedance and which isolates the DUT from the d.c. power supply in that frequency range.
3.2
burst
transient comprised of a complex series of transient voltage variations
Note 1 to entry: For bursts, in addition to the parameters given in the definitions; 3.2.1, 3.2.2 and 3.2.3 are also
relevant. For an illustration of a burst transient waveform, see ISO 7637–2.
3.2.1
burst cycle time
time between the start of the first pulse (3.13) of two consecutive bursts (3.2)
3.2.2
burst duration
time during which a complex series of transient voltage variations occurs during a single burst (3.2)
3.2.3
time between bursts
time between the end of one burst (3.2) and the start of the next one
3.3
coupling
means or device for transferring power between systems
Note 1 to entry: For coupling, in addition to the parameters given in the definitions; 3.3.1 and 3.3.2 are also relevant.
[SOURCE: IEC 60050–726–14–01, modified]
3.3.1
coupling clamp
device of defined dimensions and electromagnetic characteristics designed for common-mode coupling
(3.3) of the disturbance transient to the circuit under test without any galvanic connection to it
3.3.1.1
capacitive coupling clamp
CCC
special fixture that facilitates capacitive coupling (3.3) of fast transient test pulses (3.15) into signal lines
under test without any galvanic connection to the terminals of the circuits, or any other part of the DUT
3.3.1.2
inductive coupling clamp
ICC
bulk current injection (BCI) type probe to provide the means of coupling (3.3) slow transient test pulses
(3.15) into signal lines under test without any galvanic connection to the terminals of the circuits, or
any other part of the DUT
3.3.2
coupling network
electrical circuit for the purpose of transferring energy from one circuit to another
3.3.3
direct capacitive coupling
DCC
method using discrete, non-polarized capacitor to couple fast and slow transient test pluses into the
DUT’s signal lines under test
3.4
degradation
〈of performance〉 undesired departure in the operational performance of any device, equipment or
system from its intended performance
Note 1 to entry: The term “degradation” can apply to temporary or permanent failure.
[SOURCE: IEC 60050-161-01-19]
3.5
electromagnetic compatibility
EMC
ability of an equipment or system to function satisfactorily in its electromagnetic environment without
introducing intolerable electromagnetic disturbances (3.6) to anything in that environment
[SOURCE: IEC 60050-161-01-07]
3.6
electromagnetic disturbance
any electromagnetic phenomenon which can degrade the performance of a device, equipment or system,
or adversely affect living or inert matter
Note 1 to entry: An electromagnetic disturbance may be an electromagnetic noise, an unwanted signal or a
change in the propagation medium itself.
[SOURCE: IEC 60050-161-01-05]
2 © ISO 2015 – All rights reserved

3.7
electromagnetic interference
EMI
degradation (3.4) of the performance of equipment, transmission channel or system caused by an
electromagnetic disturbance (3.6)
Note 1 to entry: The English words “interference” and “disturbance” are often used indiscriminately.
[SOURCE: IEC 60050-161-01-06, modified]
3.8
electromagnetic radiation
phenomenon by which energy in the form of electromagnetic waves emanates from a source into space;
energy transferred through space in the form of electromagnetic waves
Note 1 to entry: By extension, the term “electromagnetic radiation” sometimes also covers induction phenomena.
[SOURCE: IEC 60050-731-01-01, modified]
3.9
susceptibility
〈electromagnetic〉 inability of a device, equipment or system to perform without degradation (3.4) in
the presence of an electromagnetic disturbance (3.6)
Note 1 to entry: Susceptibility is a lack of immunity.
[SOURCE: IEC 60050-161-01-21]
3.10
ground (reference) plane
flat conductive surface whose potential is used as a common reference
[SOURCE: IEC 60050-161]
3.11
immunity (to a disturbance)
ability of a device, equipment or system to perform without degradation (3.4) in the presence of an
electromagnetic disturbance (3.6)
[SOURCE: IEC 60050-161-01-20]
3.12
peak amplitude
highest absolute value of the amplitude of a transient (3.17)
3.13
pulse
comparatively smooth transient (3.17) with defined shape and time characteristics
Note 1 to entry: For pulses, the definitions given in 3.13.1, 3.13.2, 3.13.3, and 3.13.4 relative to pulse characteristics
are also relevant.
3.13.1
pulse duration
time from the instant the absolute value of the pulse (3.13) rises above 10 % of the absolute value of the
peak amplitude (3.12) to the instant it falls below 10 % of this
3.13.2
pulse fall time
time taken for the absolute value of the pulse (3.13) to decrease from 90 % to 10 % of the absolute va
...