IEC 61000-4-28:1999+AMD1:2001+AMD2:2009 CSV

Electromagnetic compatibility (EMC) - Part 4-28: Testing and measurement techniques - Variation of power frequency, immunity test for equipment with input current not exceeding 16 A per phase

IEC 61000-4-28:1999+A1:2001+A2:2009 establishes a reference for evaluating the immunity of electric and electronic equipment when subjected to variations of the power frequency. Only conducted phenomena are considered, including immunity tests for equipment connected to public and industrial networks. This consolidated version consists of the first edition (1999), its amendment 1 (2001) and its amendment 2 (2009). Therefore, no need to order amendments in addition to this publication.

Compatibilité électromagnétique (CEM) - Partie 4-28: Techniques d'essai et de mesure - Essai d'immunité à la variation de la fréquence d'alimentation pour des matériels avec un courant appelé n'excédant pas 16 A par phase

La CEI 61000-4-28:1999+A1:2001+A2:2009 définit une référence pour évaluer l'immunité des matériels électriques et électroniques lorsque ceux-ci sont soumis à des variations de la fréquence de l'alimentation. Ne sont pris en compte que les phénomènes conduits, notamment les essais d'immunité des matériels raccordés aux réseaux de distribution publics ou industriels.  Cette version consolidée comprend la première édition (1999), son amendement 1 (2001) et son amendement 2 (2009). Il n'est donc pas nécessaire de commander les amendements avec cette publication.

General Information

• Status: Published
• Publication Date: 06-Apr-2009
• ICS: 01 - GENERALITIES. TERMINOLOGY. STANDARDIZATION. DOCUMENTATION
• ICS: 27.120.10 - Reactor engineering
• ICS: 27.120.20 - Nuclear power plants. Safety
• ICS: 33.100.20 - Immunity
• Technical Committee: SC 77A - EMC - Low frequency phenomena
• Current Stage: PPUB - Publication issued
• Start Date: 07-Apr-2009
• Completion Date: 07-Apr-2009

Standards Content (Sample)

IEC 61000-4-28
®
Edition 1.2 2009-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
BASIC EMC PUBLICATION
PUBLICATION FONDAMENTALE EN CEM
Electromagnetic compatibility (EMC) –
Part 4-28: Testing and measurement techniques – Variation of power frequency,
immunity test for equipment with input current not exceeding 16 A per phase

Compatibilité électromagnétique (CEM) –
Partie 4-28: Techniques d'essai et de mesure – Essai d'immunité à la variation de
la fréquence d'alimentation pour des matériels avec un courant appelé
n’excédant pas 16 A par phase
IEC 61000-4-28:1999+A1:2001+A2:2009

---------------------- Page: 1 ----------------------
THIS PUBLICATION IS COPYRIGHT PROTECTED
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IEC 61000-4-28
®
Edition 1.2 2009-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
BASIC EMC PUBLICATION
PUBLICATION FONDAMENTALE EN CEM
Electromagnetic compatibility (EMC) –
Part 4-28: Testing and measurement techniques – Variation of power frequency,
immunity test for equipment with input current not exceeding 16 A per phase

Compatibilité électromagnétique (CEM) –
Partie 4-28: Techniques d'essai et de mesure – Essai d'immunité à la variation
de la fréquence d'alimentation pour des matériels avec un courant appelé
n’excédant pas 16 A par phase

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CF
CODE PRIX
ICS 33.100.20 ISBN 978-2-88910-390-4
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

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– 2 – 61000-4-28 © IEC:1999+A1:2001
+A2:2009
CONTENTS
FOREWORD.3
INTRODUCTION.5

1 Scope.6
2 Normative references.6
3 General.7
4 Definitions.7
5 Test levels.7
6 Test equipment.8
6.1 Test generators: characteristics and performances .8
6.2 Verification of the characteristics .9
7 Test set-up.10
8 Test procedure.10
8.1 Climatic conditions.10
8.2 Execution of the test .10
9 Evaluation of test results.11
10 Test report.11

Annex A (informative) Sources and effects of variation of the power frequency .14
Annex B (informative) Electromagnetic environment classes.15

Figure 1 – Frequency variation sequence .12
Figure 2 – Example of transitional period t .12
p
Figure 3 – Schema of test instrumentation with power amplifier .13
Figure 4 – Example of test generator verification load.9

Table 1 – Test levels for frequency variations .8
Table 2 – Characteristics of the generator .8

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61000-4-28 © IEC:1999+A1:2001 – 3 –
+A2:2009
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ELECTROMAGNETIC COMPATIBILITY (EMC) –

Part 4-28: Testing and measurement techniques –
Variation of power frequency, immunity test for equipment
with input current not exceeding 16 A per phase



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 61000-4-28 has been prepared by subcommittee 77A: Low-
frequency phenomena, of IEC technical committee 77: Electromagnetic compatibility.
This standard forms part 4-28 of the IEC 61000 series. It has the status of a basic EMC
publication in accordance with IEC Guide 107.
This consolidated version of IEC 61000-4-28 consists of the first edition (1999) [77A/287/FDIS
and 77A/299/RVD], its amendment 1 (2001) [77B/291+293/FDIS and 77B/298+300/RVD] and
its amendment 2 (2009) [77A/673/FDIS and 77A/676/RVD].
The technical content is therefore identical to the base edition and its amendments and has
been prepared for user convenience.
It bears the edition number 1.2.

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+A2:2009
A vertical line in the margin shows where the base publication has been modified by
amendments 1 and 2.
Annexes A and B are for information only.
The committee has decided that the contents of the base publication and its amendments will
remain unchanged until the maintenance result 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.

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61000-4-28 © IEC:1999+A1:2001 – 5 –
+A2:2009
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 (in so far 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 Standard,
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 completed by a
second number identifying the subdivision.

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+A2:2009
ELECTROMAGNETIC COMPATIBILITY (EMC) –

Part 4-28: Testing and measurement techniques –
Variation of power frequency, immunity test for equipment
with input current not exceeding 16 A per phase



1 Scope
This part of IEC 61000 is a basic EMC (electromagnetic compatibility) publication. It considers
immunity tests for electric and/or electronic equipment in its electromagnetic environment. Only
conducted phenomena are considered, including immunity tests for equipment connected to
public and industrial networks.
The object of this part is to establish a reference for evaluating the immunity of electric and
electronic equipment when subjected to variations of the power frequency.
This standard applies to electric and/or electronic equipment connected to 50 Hz or 60 Hz
distributed network with rated line current up to 16 A per phase.
It does not apply to electric and/or electronic equipment connected to a.c. 400 Hz distribution
networks. Tests concerning these networks will be covered by other IEC standards.
In general, electrical and electronic equipment is not susceptible to minor variations of the
power frequency. Testing according to this standard should be limited to products which are
assessed to be susceptible to power frequency variations by virtue of design, environment or
failure consequences.
The immunity test levels required for a specific electromagnetic environment together with the
performance criteria are indicated in the product, product family or generic standards as
applicable.
2 Normative references
The following referenced documents are indispensable for the application of this document. For
dated references, only the edition cited applies. For undated references, the latest edition of
the referenced document (including any amendments) applies.
IEC 60050(161), International Electrotechnical Vocabulary (IEV) – Chapter 161 Electro-
magnetic compatibility
IEC 60068-1, Environmental testing – Part 1: General and guidance
IEC 61000-2-4, Electromagnetic compatibility (EMC) – Part 2: Environment – Section 4: Com-
patibility levels in industrial plants for low-frequency conducted disturbances

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61000-4-28 © IEC:1999+A1:2001 – 7 –
+A2:2009
3 General
The purpose of the test is to investigate effects of power frequency variations on equipment
which may be sensitive to this disturbance. The effects are generally instantaneous.
Electrical and electronic equipment may be affected by variations of the power frequency.
The frequency of a.c. power derived from public systems is directly related to the rotational
speed of the generators, as is the frequency of a.c. power derived from an alternator which is
separate from the public network. The frequency depends at any instant on the dynamic
balance between the loads and the capacity of the generating plants. Consequently, as this
dynamic balance changes, small changes in frequency will occur. The size and duration of
these changes depends on the characteristics of the load changes and response of the
generating plant to the load changes. Where the supply is derived from an independent
inverter, the frequency may be derived from the control circuitry and is then fixed.
The frequency of public systems is, under normal conditions, generally declared by the supplier
in terms of a nominal value (50 Hz or 60 Hz) with a small bandwidth within which these
changes in frequency will normally be limited. However, in non-interconnected systems (small
networks isolated like islands), variations of frequency are likely to be greater and
consequently more important.
Frequency variations can affect
– control systems referring to time (measurement errors, loss of synchronization, etc.);
– equipment including passive filter (de-tuned).

4 Definitions
For the purposes of this part of IEC 61000, the following definitions and terms apply as well as
the definitions of IEC 60050(161).
4.1
immunity
ability of a device, equipment or system to perform without degradation in the presence of an
electromagnetic disturbance [IEV 161-01-20]
4.2
malfunction
termination of the ability of an equipment to carry out intended functions or the execution of
unintended functions by the equipment
5 Test levels
The test is performed at nominal mains voltage.
The equipment under test (EUT) is initially in operation at a mains frequency f and is then
1
subjected to frequency variation sequence according to figure 1.
Δf/f is specified as a percentage of nominal frequency f .
1 1

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+A2:2009
Test values are specified in table 1.
Table 1 – Test levels for frequency variations
Test levels Transitional period t
Frequency variation (Δf/f )
p
1
Level 1 No test required No test required
Level 2 ±3 % 10 s
Level 3 +4 % 10 s
–6 %
Level 4 ±15 % 1 s
Level X Open Open

During the transitional period, t , (figure 2), the maximum change in frequency per cycle shall
p
be less than 0,5 % of f .
1
Levels 1 and 2 are specified for equipment in relation to class 1 and 2 in IEC 61000-2-4
respectively (see annex B).
Levels 3 and 4 are specified for equipment of which the misoperation is critical for specific
application. These two test levels cover the frequency variations 100 % of the week.
Level 3 is specified for interconnected networks and level 4 is specified for non-interconnected
networks.
X is an open test level. All of the levels can be proposed by a product committee, however, the
value shall not be less than level 2 for equipment connected to public networks
NOTE The upper and the lower frequency operation limits defined by the product manufacturer should not,
however, be exceeded.
6 Test equipment
6.1 Test generators: characteristics and performances
The generator shall have provisions to prevent the emission of heavy disturbances which, if
injected in the power supply network, may influence the test results.
Table 2 – Characteristics of the generator
Output voltage accuracy ±2 %
Output voltage and current capability The generator shall be able to supply enough voltage
and current according to the type of EUT
Phase accuracy for each phase 2° (0,5 % of 360°)
Frequency accuracy 0,3 % of f (50 Hz or 60 Hz)
1
Frequency capability range f ± 20 %
1
Test duration accuracy ±10 %

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61000-4-28 © IEC:1999+A1:2001 – 9 –
+A2:2009
6.2 Verification of the characteristics
It is recognized that there is a wide range of EUTs, and that consequently test generators with
different output power capabilities may be utilized, as required by particular tests.
It shall be verified that the test generator meets the characteristics and performance
specifications as listed in Table 2.
Performance of the test generator shall be verified with a resistive load drawing an r.m.s.
current of no more than the output capability of the generator. For example, a 230V/16A
generator shall be verified with a 14,3 Ω load.
In addition, the generator’s output current capability shall be verified as being able to provide a
crest factor of at least 3 when U is applied to a single phase load drawing an rms current of
N
no more than the output capability of the generator. Each output phase of the generator shall
be verified in turn. An example of a 230 V/16 A verification load is given in Figure 4.
R
a
B
G
+
R
C
IEC  229/09


Components
G Test generator
B Bridge rectifier
C 11 000 μF ± 20 % electrolytic capacitor
R 61 Ω ± 1 % resistor
R Additional resistor
a
NOTE R is selected so that the total series resistance (sum of the additional resistor R , the wiring resistance
a a
R , the internal resistance of two conducting diodes R and the internal resistance of the capacitor R ) is
wire diodes c
92 mΩ (±10 %).
Figure 4 – Example of test generator verification load

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+A2:2009
7 Test set-up
Figure 3 shows the test configuration for mains supply simulation.
Waveform generators and power amplifiers are used.
Tests on the threephase EUT are accomplished by using generators with synchronization
between each phase.
8 Test procedure
Before starting the test of a given equipment, a test plan shall be prepared.
It is recommended that the test plan shall identify the following:
– the type designation of the EUT;
– information on possible connections (plugs, terminals, etc.) and corresponding cables and
peripherals;
– input power port of equipment to be tested;
– representative operational modes of the EUT for the test;
– performance criteria used and defined in the technical specifications;
– description of the test set-up.
If the actual operating signal sources are not available to the EUT, they may be simulated.
For each test, any degradation of performance shall be recorded. The monitoring equipment
should be capable of displaying the status of the operational mode of the EUT during and after
the tests. After the test, a representative functional check shall be performed.
8.1 Climatic conditions
Unless otherwise specified by the committee responsible for the generic or product standard,
the climatic conditions in the laboratory shall be within any limits specified for the operation of
the EUT and the test equipment by their respective manufacturers.
Tests shall not be performed if the relative humidity is so high as to cause condensation on the
EUT or the test equipment.
NOTE Where it is considered that there is sufficient evidence to demonstrate that the effects of the phenomenon
covered by this standard are influenced by climatic conditions, this should be brought to the attention of the
committee responsible for this standard.
8.2 Execution of the test
The EUT shall be tested using the appropriate test level. Each test shall be performed three
times according to figure 2. Each representative mode of operation shall be tested.
For the three-phase system, all three phases shall be tested simultaneously. The frequency
variation is applied simultaneously on the three phases.

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61000-4-28 © IEC:1999+A1:2001 – 11 –
+A2:2009
9 Evaluation of test results
The test results shall be classified in terms of the loss of function or degradation of
performance of the equipment under test, relative to a performance level defined by its
manufacturer or the requestor of the test, or agreed between the manufacturer and the
purchaser of the product. The recommended classification is as follows:
a) normal performance within limits specified by the manufacturer, requestor or purchaser;
b) temporary loss of function or degradation of performance which ceases after the
disturbance ceases, and from which the equipment under test recovers its normal
performance, without operator intervention;
c) temporary loss of function or degradation of performance, the correction of which requires
operator intervention;
d) loss of function or degradation of performance which is not recoverable, owing to damage
to hardware or software, or loss of data.
The manufacturer’s specification may define effects on the EUT which may be considered
insignificant, and therefore acceptable.
This classification may be used as a guide in formulating performance criteria, by committees
responsible for generic, product and product-family standards, or as a framework for the
agreement on performance criteria between the manufacturer and the purchaser, for example
where no suitable generic, product or product-family standard exists.
10 Test report
The test report shall contain all the information necessary to reproduce the test. In particular,
the following shall be recorded:
– the items specified in the test plan required by clause 8 of this standard;
– identification of the EUT and any associated equipment, for example, brand name, product
type, serial number;
– identification of the test equipment, for example, brand name, product type, serial number;
– any special environmental conditions in which the test was performed, for example, shielded
enclosure;
– any specific conditions necessary to enable the test to be performed;
– performance level defined by the manufacturer, requestor or purchaser;
– performance criterion specified in the generic, product or product-family standard;
– any effects on the EUT observed during or after the application of the test disturbance, and
the duration for which these effects persist;
– the rationale for the pass/fail decision (based on the performance criterion specified in the
generic, product or product-family standard, or agreed between the manufacturer and the
purchaser);
– any specific conditions of use, for example cable length or type, shielding or grounding, or
EUT operating conditions, which are required to achieve compliance.

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+A2:2009
f f − Δf f
1 1 1
t
t p
p
t t
p p
f + Δf
f f
1 1 1
60 s 120 s
120 s 60 s
IEC  1588/99


Figure 1 – Frequency variation sequence

tp
f1f t f1+  ff + ΔΔf
1 p 1

IEC  1589/99
Figure 2 – Example of transitional period t
p

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61000-4-28 © IEC:1999+A1:2001 – 13 –
+A2:2009

One or
three
phases
Controller
Waveform
Power
generator
amplifier
Power
Voltmeter
supply
oscilloscope
EUT
Neutral
IEC  1590/99


Figure 3 – Schema of test instrumentation with power amplifier

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+A2:2009
Annex A
(informative)

Sources and effects of variation of the power frequency

A.1 Sources
In public supply systems, there is normally an excess of capacity over load demand in order to
maintain frequency changes within the declared bandwidth. However, rare fault conditions may
arise under which, for example, a large block of load or generation is disconnected with a
resultant change in frequency outside the normal tolerance band. In such cases, some of the
load or generation will be automatically or manually disconnected to restore the balance as far
as possible.
Rotating loads which are not speed-controlled usually take less power at a lower frequency so
that loss of generation may to some extent be compensated by lower demand.
A.2 Effects
Within the normal tolerances encountered, the main effect of a change in power frequency is
on the speed of rotation machines. Hence, mains electrical clocks will lose or gain time and
other motors will del
...