ISO 11452-2:1995

INTERNATIONAL
IS0
STANDARD
11452-2
First edition
1995-l Z-01
Road vehicles - Electrical disturbances
by narrowband radiated electromagnetic
energy - Component test methods -
Part 2:
Absorber-lined chamber
VGhicules routiers - Perturbations Blectriques par rayonnemen t d’energie
Glectromagnti tique en bande &roite - M6 thodes d’essai d’un
composant -
Partie 2: Chambre ankhoi’que
Reference number
IS0 11452-z: 1995(E)

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IS0 11452=2:1995(E)
Contents
Page
1
1 Scope . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1
2 Normative reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1
3 Test conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1
....................................
3.1 Test temperature and supply voltage
2
.....................................................................
3.2 Frequency range
2
..............................................................................
3.3 Modulation
2
3.4 Dwell time .
.............................................................. 2
3.5 Frequency step sizes
2
3.6 Test severity levels .
........................ 2
4 Test instrument description and specifications
2
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4.1 Absorber-lined chamber
3
......................................................................
4.2 Instrumentation
.............................................................................. 3
4.3 Test set-up
7
5 Test procedures .
7
5.1 Test plan .
7
5.2 Test methods . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5.3 Test report
Annex
9
. . . . . . . . . . . . . . . . .
A Function performance status classification (FPSC)
0 IS0 1995
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced
or utilized in any form or by any means, electronic or mechanical, including photocopying and
microfilm, without permission in writing from the publisher.
International Organization for Standardization
Case Postale 56 l CH-1211 Geneve 20 l Switzerland
Printed in Switzerland
ii

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0 IS0
IS0 11452=2:1995(E)
Foreword
IS0 (the International Organization for Standardization) is a worldwide
federation of national standards bodies (IS0 member bodies). The work
of preparing International Standards is normally carried out through IS0
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. IS0
collaborates closely with the International Electrotechnical Commission
(IEC) on all matters of electrotechnical standardization.
Draft International Standards adopted by the technical committees are
circulated to the member bodies for voting. Publication as an International
Standard requires approval by at least 75 % of the member bodies casting
a vote.
International Standard IS0 114522 was prepared by Technical Committee
lSO/TC 22, Road vehicles, Subcommittee SC 3, Electrical and electronic
equipment.
IS0 11452 consists of the following parts, under the general title Road
vehicles - Electrical disturbances by narrowband radiated electro-
magnetic energy - Component test methods:
- Part 1: General and definitions
- Part 2: Absorber-lined chamber
- Part 3: Transverse electromagnetic mode (TEM) cell
- Part 4: Bulk current injection (BCI)
- Part 5: Stripline
- Part 6: Parallel plate antenna
- Part 7: Direct radio frequency (RF) power injection
Annex A of this part of IS0 11452 is for information only.
. . .
III

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IS0 11452-2:1995(E)
INTERNATIONAL STANDARD 0 IS0
Road vehicles - Electrical disturbances
by narrowband radiated electromagnetic energy -
Component test methods -
Part 2:
Absorber-lined chamber
1 Scope 2 Normative reference
The following standard contains provisions which,
This part of IS0 11452 specifies test methods and
through reference in this text, constitute provisions
procedures for testing electromagnetic immunity (off-
of this part of IS0 11452. At the time of publication,
vehicle radiation sources) of electronic components
the edition indicated was valid. All standards are sub-
for passenger cars and commercial vehicles regard-
ject to revision, and parties to agreements based on
less of the propulsion system (e.g. spark-ignition en-
this part of IS0 11452 are encouraged to investigate
gine, diesel engine, electric motor). To perform this
the possibility of applying the most recent edition of
test method, the electronic module along with the
the standard indicated below. Members of IEC and
wiring harness (prototype or standard test harness)
IS0 maintain registers of currently valid International
and peripheral devices are subjected to the electro-
Standards.
magnetic disturbance generated inside an absorber-
lined chamber. The electromagnetic disturbances IS0 11452-l : 1995, Road vehicles - Electrical dis-
considered in this part of IS0 11452 are limited to turbances by narrowband radiated electromagnetic
continuous narrowband electromagnetic fields. energy - Component test methods - Part 1: Gen-
eral and definitions.
Immunity measurements of complete vehicles are
generally only possible by the vehicle manufacturer.
The reasons,, for example, are the high costs of an
3 Test conditions
absorber-lined chamber, preserving the secrecy of
prototypes, or the large number of different vehicle
3.1 Test temperature and supply voltage
models. Therefore, for research, development and
quality control, a laboratory measuring method is used
The ambient temperature during the test shall be
by the manufacturer.
(23 + 5) “C.
The supply voltage during the test shall be
Part 1 of IS0 11452 gives general information, defi-
(13,5 + 0,5) V for 12 V electrical systems and
nitions, practical use and basic principles of the test
(27 +T) V for 24 V electrical systems.
procedure. -

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0 IS0
IS0 11452-2:1995(E)
If other values are agreed by the users of this part of
3.6 Test severity levels
IS0 11452, the values shall be documented in the
test report.
The user should specify the test severity level(s) for
the field strength over the frequency range.
Suggested test severity levels are given in annex A.
3.2 Frequency range
These test severity levels are expressed in terms of
The applicable frequency range of the test method is
the equivalent root-mean-square value of the unmod-
200 MHz to 18 000 MHz.
ulated wave.
Tests are generally performed in both horizontal and
3.3 Modulation
vertical polarizations over the test frequency range.
Any exceptions to this practice shall be specified in
The device under test determines tt- e type and fre-
the test plan.
quency of modulation. If no values
are agreed be-
tween the users of this part of SO 11452, the
following shall be used:
- no modulation (CW);
4 Test instrument description and
specifications
- 1 kHz sine-wave amplitude modulation (AM) of
80 %.
For the test, radiated electromagnetic fields are gen-
erated by using antenna sets with radio frequency
(RF) sources capable of producing the desired field
3.4 Dwell time
strengths over the range of test frequencies. The
fields are monitored with small probes to ensure
At each frequency, the device under test shall be ex-
proper test levels. To reduce test error, the operation
posed to the test level for the minimum response
of the device under test is usually monitored by op-
time needed to control it. In all cases, this minimum
tical couplers.
time of exposure shall not be less than 2 s.
3.5 Frequency step sizes
4.1 Absorber-lined chamber
All tests in this part of IS0 11452 shall be conducted
The objective of an absorber-lined chamber is to cre-
with linear frequency step sizes not greater than
ate an indoor electromagnetic compatibility test fa-
those specified in table 1.
cility which simulates open field testing. The chamber
is lined with absorbing material on as many surfaces
Table 1 - Frequency step sizes
in the chamber as possible to minimize reflections and
resonances. The design objective is to reduce the
Maximum
Frequency band
reflectivity in the test area to - 10 dB or less.
frequency step size
MHz MHz
The size, shape and construction of an absorber-lined
chamber can vary considerably. The chamber shape
>200 to is a function of the types of tests to be per-formed, the
>I 000 to size of the device to be tested and the frequency
range to be covered. Basically, an absorber-lined
chamber consists of a shielded room with absorbing
Alternatively, logarithmic frequency steps, with the
material on its internal reflective surfaces, optionally
same minimum number of frequency steps in each
excluding the floor. The minimum size of the room is
frequency band, may be used. The values, as agreed
determined by the size of the test region needed, the
by the users of this part of IS0 11452 shall be docu-
size of the field generation device and the clearances
mented in the test report.
required between them and the largest device that is
to be tested. To create the test region, the absorber,
If it appears that the susceptibility thresholds of the
device under test are very near the chosen test level, field generation system, and chamber shape are
these frequency step sizes should be reduced in the selected to reduce the amount of extraneous energy
frequency range concerned in order to find the mini- in the test region below a minimum value which will
mum susceptibility thresholds. give the desired measurement accuracy.
2

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0 IS0 IS0 11452-2:1995(E)
Power shall be applied to the device under test via a
4.2 Instrumentation
5 pH/50 Sz artificial network.
4.2.1 Field generating device
4.3.2 Location of field generating device
The field generatin
...