ISO 11451-1:2015
(Main)Road vehicles — Vehicle test methods for electrical disturbances from narrowband radiated electromagnetic energy — Part 1: General principles and terminology
Road vehicles — Vehicle test methods for electrical disturbances from narrowband radiated electromagnetic energy — Part 1: General principles and terminology
ISO 11451-1:2015 specifies general conditions, defines terms, gives practical guidelines, and establishes the basic principles of the vehicle tests used in the other parts of ISO 11451, for determining the immunity of passenger cars and commercial vehicles to electrical disturbances from narrowband radiated electromagnetic energy, regardless of the vehicle propulsion system (e.g. spark-ignition engine, diesel engine, electric motor). The electromagnetic disturbances considered are limited to continuous narrowband electromagnetic fields. A wide frequency range (0,01 MHz to 18 000 MHz) is allowed for the immunity testing in this and the other parts of ISO 11451.
Véhicules routiers — Méthodes d'essai d'un véhicule soumis à des perturbations électriques par rayonnement d'énergie électromagnétique en bande étroite — Partie 1: Principes généraux et terminologie
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Standards Content (Sample)
INTERNATIONAL ISO
STANDARD 11451-1
Fourth edition
2015-06-01
Road vehicles — Vehicle test methods
for electrical disturbances from
narrowband radiated electromagnetic
energy —
Part 1:
General principles and terminology
Véhicules routiers — Méthodes d’essai d’un véhicule soumis
à des perturbations électriques par rayonnement d’énergie
électromagnétique en bande étroite —
Partie 1: Principes généraux et terminologie
Reference number
ISO 11451-1:2015(E)
©
ISO 2015
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ISO 11451-1:2015(E)
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ISO 11451-1:2015(E)
Contents Page
Foreword .iv
Introduction .v
1 Scope . 1
2 Normative references . 1
3 Terms and definitions . 1
4 General aim and practical use . 5
5 General test conditions . 6
5.1 General . 6
5.2 Test temperature . 7
5.3 Supply voltage . . 7
5.3.1 Vehicle Low Voltage (LV) power supply. 7
5.3.2 Hybrid or electric vehicle not connected to power mains . 7
5.3.3 Hybrid or electric vehicle in charging mode (AC or DC) . 7
5.4 Modulation . 7
5.5 Dwell time . 8
5.6 Frequency step sizes . 8
5.7 Definition of test severity levels . 9
5.8 Disturbance application . 9
6 Instrumentation . 9
6.1 AN, AMN, and AAN . 9
6.2 Test signal quality . 9
7 Test procedure .10
7.1 Test plan .10
7.2 Test methods .10
7.2.1 General.10
7.2.2 Substitution .10
7.2.3 Closed loop levelling .11
7.2.4 Vehicle immunity measurement .11
7.3 Test report .12
Annex A (normative) Function Performance Status Classification (FPSC) .13
Annex B (normative) Artificial Networks (AN), Artificial Mains Networks (AMN) and
Asymmetric Artificial Networks (AAN) .16
Annex C (informative) Constant peak test level .22
Bibliography .25
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ISO 11451-1:2015(E)
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
through ISO technical committees. Each member body interested in a subject for which a technical
committee has been established has the right to be represented on that committee. International
organizations, governmental and non-governmental, in liaison with ISO, also take part in the work.
ISO collaborates closely with the International Electrotechnical Commission (IEC) on all matters of
electrotechnical standardization.
The procedures used to develop this document and those intended for its further maintenance are
described in the ISO/IEC Directives, Part 1. In particular the different approval criteria needed for the
different types of ISO documents should be noted. This document was drafted in accordance with the
editorial rules of the ISO/IEC Directives, Part 2 (see www.iso.org/directives).
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. ISO shall not be held responsible for identifying any or all such patent rights. Details of
any patent rights identified during the development of the document will be in the Introduction and/or
on the ISO list of patent declarations received (see www.iso.org/patents).
Any trade name used in this document is information given for the convenience of users and does not
constitute an endorsement.
For an explanation on the meaning of ISO specific terms and expressions related to conformity
assessment, as well as information about ISO’s adherence to the WTO principles in the Technical 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 fourth edition cancels and replaces the third edition (ISO 11451-1:2005), which has been technically
revised. It also incorporates the Amendment ISO 11451-1:2005/Amd 1:2008.
ISO 11451 consists of the following parts, under the general title Road vehicles — Vehicle test methods for
electrical disturbances from narrowband radiated electromagnetic energy:
— Part 1: General principles and terminology
— Part 2: Off-vehicle radiation sources
— Part 3: On-board transmitter simulation
— Part 4: Bulk current injection (BCI)
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ISO 11451-1:2015(E)
Introduction
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.
Electrical and radio-frequency disturbances occur during the normal operation of many items of
motor vehicle equipment. They are generated over a wide frequency range with various electrical
characteristics and can be distributed to on-board electronic devices and systems by conduction,
radiation, or both. Narrowband signals generated from sources on or off the vehicle can also be coupled
into the electrical and electronic system, affecting the normal performance of electronic devices. Such
sources of narrowband electromagnetic disturbances include mobile radios and broadcast transmitters.
The characteristics of the immunity of a vehicle to radiated disturbances have to be established.
ISO 11451 provides various test methods for the evaluation of vehicle immunity characteristics (not all
methods need be used to test a vehicle).
ISO 11451 is not intended as a product specification and cannot function as one (see A.1). Therefore, no
specific values for the test severity level are given.
Annex A specifies a general method for function performance status classification (FPSC), Annex
B specifies Artificial Networks (AN), Artificial Mains Networks (AMN) and Asymmetric Artificial
Networks (AAN), while annex C explains the principle of constant peak test level. Typical severity levels
are included in an annex of each of the other parts of ISO 11451.
Protection from potential disturbances needs to be considered in a total system validation, and this can
be achieved using the various parts of ISO 11451.
NOTE Immunity measurements of complete vehicles are generally able to be carried out only by the vehicle
manufacturer, owing to, for example, high costs of absorber-lined shielded enclosures, the desire to preserve
the secrecy of prototypes or a large number of different vehicle models. ISO 11452 specifies test methods for the
analysis of component immunity, which are better suited for supplier use.
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INTERNATIONAL STANDARD ISO 11451-1:2015(E)
Road vehicles — Vehicle test methods for electrical
disturbances from narrowband radiated electromagnetic
energy —
Part 1:
General principles and terminology
1 Scope
This part of ISO 11451 specifies general conditions, defines terms, gives practical guidelines, and
establishes the basic principles of the vehicle tests used in the other parts of ISO 11451, for determining
the immunity of passenger cars and commercial vehicles to electrical disturbances from narrowband
radiated electromagnetic energy, regardless of the vehicle propulsion system (e.g. spark-ignition engine,
diesel engine, electric motor).
The electromagnetic disturbances considered are limited to continuous narrowband electromagnetic
fields. A wide frequency range (0,01 MHz to 18 000 MHz) is allowed for the immunity testing in this and
the other parts of ISO 11451.
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.
CISPR 16-1-2, Specification for radio disturbance and immunity measuring apparatus and methods —
Part 1-2: Radio disturbance and immunity measuring apparatus — Ancillary equipment — Conducted
disturbances; Edition 1.2.
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
absorber-lined shielded enclosure
shielded enclosure/screened room with radio frequency absorbing material on its internal ceiling and
walls
Note 1 to entry: The common practice is for the room to have a metallic floor, but absorbing material can also be
used on the floor.
3.2
amplitude modulation
AM
process by which the amplitude of a carrier wave is varied following a specified law, resulting in an AM
signal
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ISO 11451-1:2015(E)
3.3
artificial mains network
AMN
provides a defined impedance to the EUT at radio frequencies, couples the disturbance voltage to the
measuring receiver, and decouples the test circuit from the supply mains
Note 1 to entry: There are two basic types of AMN, the V-network (V-AMN) which couples the unsymmetrical
voltages and the delta-network which couples the symmetric and the asymmetric voltages separately. The terms
line impedance stabilization network (LISN) and V-AMN are used.
Note 2 to entry: This network is inserted in the power mains of the vehicle in charging mode and provides, in a
given frequency range, a specified load impedance and which isolates the vehicle from the power mains in that
frequency range.
3.4
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: This network is inserted in the DC power lines of the vehicle in charging mode and provides, in
a given frequency range, a specified load impedance and which isolates the vehicle from the DC power supply in
that frequency range.
3.5
asymmetric artificial network
AAN
network used to measure (or inject) asymmetric (common mode) voltages on unshielded symmetric
signal (e.g. telecommunication) lines while rejecting the symmetric (differential mode) signal
Note 1 to entry: This network is inserted in the communication/signal lines of the vehicle in charging mode to
provide a specific load impedance and/or a decoupling (e.g. between communication/signal lines and power
mains).
3.6
bonded (ground connection and DC resistance)
grounding connection where the purpose of the bonding is to provide the lowest possible impedance
(resistance and inductance) connection between two metallic parts with a d.c. resistance which shall
not exceed 2,5 mΩ
Note 1 to entry: A low current (≤100 mA) 4-wire milliohm meter is recommended for this measurement.
3.7
bulk current
total amount of common mode current in a harness
3.8
compression point
input signal level at which the measurement system becomes non-linear
Note 1 to entry: When the measurement system is non-linear, the output value will deviate from the value given
by an ideal linear system.
3.9
coupling
means or device for transferring power between systems
[SOURCE: IEC 60050-726]
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ISO 11451-1:2015(E)
3.10
current injection probe
device for injecting current in a conductor without interrupting the conductor and without introducing
significant impedance into the associated circuits
3.11
current (measuring) probe
device for measuring the current in a conductor without interrupting the conductor and without
introducing significant impedance into the associated circuits
[SOURCE: IEC 60050-161]
3.12
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]
3.13
dual directional coupler
four-port device consisting of two transmission lines coupled together in such a manner that a single
travelling wave in any one transmission line will induce a single travelling wave in the other, the direction
of propagation of the latter wave being dependent upon that of the former
[SOURCE: IEC 60050-726]
3.14
electromagnetic compatibility
EMC
ability of equipment or system to function satisfactorily in its electromagnetic environment without
introducing intolerable electromagnetic disturbance to anything in that environment
[SOURCE: IEC 60050-161]
3.15
electromagnetic disturbance
any electromagnetic phenomenon which can degrade the performance of a device, equipment, or system
or adversely affect living or inert matter
EXAMPLE An electromagnetic disturbance can be an electromagnetic noise, an unwanted signal, or a change
in the propagation medium itself.
[SOURCE: IEC 60050-161]
3.16
electromagnetic interference
EMI
degradation of the performance of equipment, transmission channel, or system caused by electromagnetic
disturbance
Note 1 to entry: The English words “interference” and “disturbance” are often used indiscriminately.
[SOURCE: IEC 60050-161]
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ISO 11451-1:2015(E)
3.17
(electromagnetic) susceptibility
inability of a device, equipment, or system to perform without degradation in the presence of an
electromagnetic disturbance
Note 1 to entry: Susceptibility is the lack of immunity.
[SOURCE: IEC 60050-161]
3.18
forward power
power supplied by the output of an amplifier or generator
3.19
ground (reference) plane
flat conductive surface whose potential is used as a common reference
[SOURCE: IEC 60050-161]
3.20
immunity (to a disturbance)
ability of a device, equipment, or system to perform without degradation in the presence of an
electromagnetic disturbance
[SOURCE: IEC 60050-161]
3.21
immunity level
maximum level of a given electromagnetic disturbance incident on a particular device, equipment, or
system for which it remains capable of operating at a required degree of performance
[SOURCE: IEC 60050-161]
3.22
narrowband emission
emission which has a bandwidth less than that of a particular measuring apparatus or receiver
[SOURCE: IEC 60050-161]
3.23
polarization (of wave or field vector)
property of sinusoidal electromagnetic wave or field vector defined at a fixed point in space by the
direction of the electric field strength vector or of any specified field vector, when this direction varies
with time
Note 1 to entry: The property can be characterized by the locus described by the extremity of the considered field
vector.
[SOURCE: IEC 60050-726]
3.24
portable transmitter
hand-held radio frequency communication device
Note 1 to entry: A portable transmitter could be a commercial device (e.g. cellular phone) or a simulated one.
3.25
power mains
general purpose alternating current (AC) or direct current (DC) electric power supply
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ISO 11451-1:2015(E)
3.26
pulse modulation
PM
process by which the amplitude of a carrier wave is varied following a specified law, resulting in a PM
signal
3.27
(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 60050-161]
3.28
reflected power
power reflected by the load due to impedance mismatch between RF-source and load
3.29
shielded enclosure
screened room
mesh or sheet metallic housing designed expressly for the purpose of separating electromagnetically
the internal and external environment
[SOURCE: IEC 60050-161]
3.30
voltage standing wave ratio
VSWR
ratio along a transmission line of a maximum to an adjacent minimum magnitude of a particular field
component of a standing wave
()1+r
VSWR =
()1−r
where r is the absolute value of the coefficient of reflection
[SOURCE: IEC 60050-726]
3.31
transmission line system
TLS
field-generating device that works in a similar way to a TEM (transverse electromagnetic) wave generator
EXAMPLE Stripline, TEM cell, parallel plate.
4 General aim and practical use
The test methods, procedures, test instrumentation, and levels specified in ISO 11451 are intended
to facilitate vehicle specification for electrical disturbances by narrowband radiated electromagnetic
energy. A basis is provided for mutual agreement between vehicle manufacturers and component
suppliers intended to assist rather than restrict.
Certain devices are particularly susceptible to some characteristics of electromagnetic disturbance,
such as frequency, severity level, type of coupling, or modulation.
Electronic devices are sometimes more susceptible to modulated, as opposed to unmodulated, radio-
frequency (RF) signals. The reason is that high-frequency disturbances can be demodulated by
semiconductors. In the case of unmodulated signals, this leads to a continuous shift of, for example, a
voltage; in the case of amplitude-modulated signals, the resulting low-frequency fluctuations can be
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ISO 11451-1:2015(E)
interpreted as intentional signals (e.g. speed information) and therefore disturb the function of the
device under test (DUT) more severely.
A single standard test may not reveal all the needed information about the DUT. It is thus necessary for
users of ISO 11451 to anticipate the appropriate test conditions, select applicable parts of ISO 11451, and
define function performance objectives. The main characteristics of each test method in ISO 11451-2 to
ISO 11451-4 are presented in Table 1.
Table 1 — Main characteristics of test methods in ISO 11451
Test severity
Applicable fre-
Part of ISO 11451 Coupling to parameter and Provisions
quency range
unit
ISO 11451-2
Components and Absorber-lined shielded
10 kHz to 18 GHz Electric field (V/m)
Off-vehicle radiation
wiring harness enclosure required
sources
ISO 11451-3
Absorber-lined shielded
Components and
1,8 MHz to 5,85 GHz Power (W) enclosure recom-
On-board transmitter
wiring harness
mended
simulation
ISO 11451-4
Shielded enclosure rec-
1 MHz to 400 MHz Wiring harness Current (mA)
Bulk current injection
ommended
(BCI)
5 General test conditions
5.1 General
Unless otherwise specified, the following test conditions are common to all parts of ISO 11451:
— test temperature;
— supply voltage;
— modulation;
— dwell time;
— frequency step sizes;
— definition of test severity level;
— test signal quality.
NOTE The use of the same parameters as those used for the component test methods given in the corresponding
parts of ISO 11451 will achieve better correlation.
Unless otherwise specified, the variables used shall have the following tolerances:
— ±10 % for durations and distances;
— ±10 % for resistances and impedances;
— and the following magnitude accuracy:
— ±1 dB for power meter including power sensor;
— ±3 dB for field probe.
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ISO 11451-1:2015(E)
5.2 Test temperature
Heat is generated in the test facility when the vehicle is operated during the performance of the test.
Sufficient cooling shall be provided to ensure that the engine does not overheat.
The ambient temperature during the test should be (23 ± 5) °C.
5.3 Supply voltage
5.3.1 Vehicle Low Voltage (LV) power supply
LV is used for d.c. operating voltages below 60 V (e.g. 12 V, 24 V, 48 V). For tests that require the vehicle
engine to be running, the electrical charging system shall be functional. For tests where the vehicle
engine is not required to be running, unless other values are specified in the test plan, the battery
voltage shall be maintained above 12 V for 12 V systems and above 24 V for 24 V systems.
5.3.2 Hybrid or electric vehicle not connected to power mains
HV is used for operating voltages from 60 V to 1000 V d.c. The minimum high voltage value shall be
defined in the test plan.
5.3.3 Hybrid or electric vehicle in charging mode (AC or DC)
The DC power supply voltage during the test shall be nominal ±10 %.
The AC power supply voltage during the test shall be nominal −15 % +10 %. The rated value of the
frequency shall be nominal ±1 %.
5.4 Modulation
The characteristics of the DUT determine the type and frequency of modulation to be used. If no values
or specific modulation techniques are agreed between the users of ISO 11451, the following shall be
used:
a) unmodulated sine wave (CW). See Figure 1 a);
b) sine wave amplitude modulated (AM) by 1 kHz sine wave at 80 % (modulation index m = 0,8) [see
Annex C and Figure 1 b)];
c) sine wave pulse modulated type 1 (PM, similar to GSM), with ton = 577 µs and period = 4 600 µs [see
Figure 1 c)];
d) sine wave pulse modulated type 2 (PM, similar to radar), with ton = 3 µs and period = 3333 µs; [see
Figure 1 d)].
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ISO 11451-1:2015(E)
In practice, PM modulation shall not be obtained using either the blanking of the amplifier or a 100 %
(modulation index m = 1) AM modulation type.
a) CW signal b) AM signal
c) PM type 1 signal d) PM type 2 signal
Key
f frequency
Figure 1 — Modulation
The following modulations should be used for all applicable parts of ISO 11451:
— CW: 0,01 MHz to 18 GHz;
— AM: 0,01 MHz to 800 MHz;
— PM type 1: 800 MHz to 1,2 GHz; 1,4 GHz to 2,7 GHz;
— PM type 2: 1,2 GHz to 1,4 GHz and 2,7 GHz to 18 GHz.
5.5 Dwell time
At each frequency, the vehicle shall be exposed to the test level for a time equal to the response time
of the vehicle system. If a dwell time is not specified in the test plan, or system response time is not
specified, then the dwell time shall be a minimum of 1 s.
5.6 Frequency step sizes
All tests in ISO 11451 shall be conducted with frequency step sizes (logarithmic or linear) not greater
than those specified in Table 2. The step sizes agreed upon by the users of this part of ISO 11451 shall be
documented in the test report.
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ISO 11451-1:2015(E)
Table 2 — Maximum frequency step sizes
Frequency band Linear steps Logarithmic steps
10 kHz to 100 kHz 10 kHz 10 %
>100 kHz to 1 MHz 100 kHz 10 %
>1 MHz to 10 MHz 1 MHz 10 %
>10 MHz to 200 MHz 5 MHz 5 %
>200 MHz to 400 MHz 10 MHz 5 %
>400 MHz to 1 GHz 20 MHz 2 %
>1 GHz to 18 GHz 40 MHz 2 %
If it appears that the susceptibility thresholds of the DUT are very near to the chosen test level, these
frequency step sizes should be reduced in the frequency range concerned in order to find the minimum
susceptibility thresholds.
5.7 Definition of test severity levels
The user should specify the test severity level or levels over the frequency range. The concept of FPSC
is detailed in Annex A. For both the substitution and closed loop levelling methods, and for tests with
unmodulated and amplitude-modulated signals, the test severity levels of ISO 11451 (electric field,
current, voltage, or power) are expressed in terms of the equivalent root-mean-square level value of the
unmodulated wave.
Both these methods use a constant peak test level for tests with unmodulated and amplitude-modulated
signals. The relationship between the mean power for the amplitude-modulated signal and the mean
power for
...
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