IEC TR 61547-1:2020

IEC TR 61547-1 ®
Edition 3.0 2020-07
TECHNICAL
REPORT
colour
inside
Equipment for general lighting purposes – EMC immunity requirements –
Part 1: Objective light flickermeter and voltage fluctuation immunity test method
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
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local IEC member National Committee for further information.

IEC Central Office Tel.: +41 22 919 02 11
3, rue de Varembé info@iec.ch
CH-1211 Geneva 20 www.iec.ch
Switzerland
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigendum or an amendment might have been published.

IEC publications search - webstore.iec.ch/advsearchform Electropedia - www.electropedia.org
The advanced search enables to find IEC publications by a The world's leading online dictionary on electrotechnology,
variety of criteria (reference number, text, technical containing more than 22 000 terminological entries in English
committee,…). It also gives information on projects, replaced and French, with equivalent terms in 16 additional languages.
and withdrawn publications. Also known as the International Electrotechnical Vocabulary

(IEV) online.
IEC Just Published - webstore.iec.ch/justpublished
Stay up to date on all new IEC publications. Just Published IEC Glossary - std.iec.ch/glossary
details all new publications released. Available online and 67 000 electrotechnical terminology entries in English and
once a month by email. French extracted from the Terms and Definitions clause of
IEC publications issued since 2002. Some entries have been
IEC Customer Service Centre - webstore.iec.ch/csc collected from earlier publications of IEC TC 37, 77, 86 and
If you wish to give us your feedback on this publication or CISPR.

need further assistance, please contact the Customer Service

Centre: sales@iec.ch.
IEC TR 61547-1 ®
Edition 3.0 2020-07
TECHNICAL
REPORT
colour
inside
Equipment for general lighting purposes – EMC immunity requirements –

Part 1: Objective light flickermeter and voltage fluctuation immunity test method

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.140.20 ISBN 978-2-8322-8532-9

– 2 – IEC TR 61547-1:2020 © IEC 2020
CONTENTS
FOREWORD . 5
INTRODUCTION . 7
1 Scope . 8
2 Normative references . 8
3 Terms, definitions, abbreviated terms and symbols . 9
3.1 Terms and definitions . 9
3.2 Abbreviated terms . 10
3.3 Symbols . 11
4 General . 11
5 Light flickermeter . 13
6 Voltage fluctuation disturbance signal . 13
6.1 General . 13
6.2 Mains signal parameters . 14
6.3 Disturbance signal parameters and test levels . 15
7 Test setup and equipment . 16
7.1 General . 16
7.2 Test voltage . 17
7.3 Optical test environment . 17
7.4 Light sensor and amplifier . 18
7.5 Signals to be measured . 18
7.6 Signal processing . 18
7.6.1 Anti-aliasing filter . 18
7.6.2 Sampling frequency . 19
7.6.3 Signal resolution . 19
8 Verification procedure . 21
8.1 General . 21
8.2 Light flickermeter . 21
8.3 Mains voltage parameters without modulation . 22
8.3.1 Nominal voltage level . 22
8.3.2 Mains frequency . 22
8.4 Voltage fluctuation level . 22
8.4.1 General . 22
8.4.2 Option 1: measure the actual modulation frequencies and voltage levels . 22
V
8.4.3 Option 2: measure values using a flickermeter . 22
P
st
8.5 Light sensor and amplifier . 23
8.6 Test environment . 23
8.7 Light flicker noise . 23
9 Test procedure . 24
9.1 General . 24
9.2 Measuring the intrinsic flicker performance . 25
9.3 Testing the flicker immunity against voltage fluctuations . 26
9.4 Dimmer compatibility testing . 26
9.5 Controlgear testing . 27
10 Conditions during testing . 27
11 Evaluation of the test result . 28

12 Test report . 28
Annex A (informative) Specification of the light flickermeter . 29
A.1 Voltage flickermeter modifications . 29
A.2 Specification of the light flickermeter . 30
A.2.1 General . 30
A.2.2 Block a: illuminance adapter . 30
A.2.3 Block b: weighting filters . 30
A.2.4 Block c: squaring multiplier, sliding mean filter and scaling . 31
A.2.5 Block d: statistical analysis . 31
A.3 Verification of the light flickermeter . 32
LM ®
A.4 Example of implementation in MATLAB . 33
P
st
Annex B (informative) Uncertainty considerations . 34
B.1 General . 34
B.2 General symbols . 34
B.3 Measurand . 34
B.4 Influence quantities . 34
B.5 Uncertainty budget . 36
Annex C (informative) Examples of test results of lighting equipment . 38
LM
C.1 Test without voltage fluctuations ( ) . 38
P
st
LM
C.2 Test with (intentional) voltage fluctuations (I) . 38
P
st
C.3 Test under dimming conditions. 42
LM
Annex D (informative) Guidance for testing based on test type . 44
P
st
Bibliography . 45

Figure 1 – Full EMC approach for mains voltage fluctuations . 12
Figure 2 – Illustration of the mains test signal including a rectangular modulated
voltage fluctuation (see Equation (1)) . 14
Figure 3 – Block diagram voltage-fluctuation immunity test . 17
Figure 4 – Example of a recorded mains voltage fluctuation and illuminance signal of a

60 W incandescent lamp . 21
LM
P
Figure 5 – Measuring . 26
st
LM
P
Figure 6 – Measuring (I) . 26
st
Figure 7 – Dimmer compatibility testing . 26
Figure 8 – Controlgear testing . 27
Figure A.1 –Structure of the IEC 61000-4-15 flickermeter that uses voltage as input . 29
Figure A.2 – Structure of the light flickermeter based on a modified voltage flickermeter . 29
Figure A.3 – Flickermeter response to different waveshapes . 33
LM
Figure C.1 – Graphical P I results for three EUTs with rectangular modulation at
( )
st
V
five frequencies ( P = 1) . 39
st
Figure C.2 – EUT1: recorded signals (no mains voltage modulation) . 40
Figure C.3 – EUT1: recorded signals (with modulation) . 41

– 4 – IEC TR 61547-1:2020 © IEC 2020
Figure C.4 – EUT2: relative illuminance – Mains voltage modulation d = 0,407 % at
V
13,5 Hz ( P = 1) . 42
st
Figure C.5 – EUT3: relative illuminance – Mains voltage modulation d = 0,407 % at
V
13,5 Hz ( P = 1) . 42
st
LM
Figure C.6 – Graphical (C) results for four EUTs under dimming conditions . 43
P
st
Table 1 – Voltage fluctuations – Test specification of voltage fluctuations applied at
input AC mains 120/230 V and 50/60 Hz . 16
LM
Table 2 – Guidance for P testing . 25
st
Table A.1 – Test specification of illuminance fluctuations for lightmeter classifier . 32
Table B.1 – Influence quantities and their recommended tolerances . 35
Table B.2 – Uncertainty budget of the voltage fluctuation immunity test . 37
LM
Table C.1 – Numerical results P calculations for three EUTs without voltage
st
modulation . 38
LM
Table C.2 – Numerical results P (I) calculations for three EUTs with voltage
st
modulation . 38
LM
Table C.3 – Numerical results (C) calculations for four EUTs under dimming
P
st
conditions . 43
LM
Table D.1 – Guidance for testing based on test conditions . 44
P
st
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
EQUIPMENT FOR GENERAL LIGHTING PURPOSES –
EMC IMMUNITY REQUIREMENTS –
Part 1: Objective light flickermeter and voltage fluctuation
immunity test method
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
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
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.
The main task of IEC technical committees is to prepare International Standards. However, a
technical committee may propose the publication of a Technical Report when it has collected
data of a different kind from that which is normally published as an International Standard, for
example "state of the art".
IEC TR 61547-1, which is a Technical Report, has been prepared by IEC technical
committee 34: Lighting.
This third edition cancels and replaces the second edition published in 2017. This edition
constitutes a technical revision.

– 6 – IEC TR 61547-1:2020 © IEC 2020
This edition includes the following significant technical changes with respect to the previous
edition:
a) the scope of this document has been clarified to make a distinction between flicker testing
without voltage fluctuations to measure the intrinsic performance of lighting equipment and
flicker testing in which a specific set of voltage fluctuations are applied in order to
measure the immunity of the lighting equipment to voltage fluctuations present on the
mains;
b) the test procedure for flicker testing has been clarified.
The text of this Technical Report is based on the following documents:
Draft TR Report on voting
34/668/DTR 34/701/RVDTR
Full information on the voting for the approval of this Technical Report can be found in the
report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 61547 series, published under the general title Equipment for
general lighting purposes – EMC immunity requirements, can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document 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.
INTRODUCTION
The fast rate at which solid state light (SSL) sources can change their intensity is one of the
main drivers behind the revolution in the lighting world and applications of lighting. Linked to
the fast rate of the intensity change is a direct transfer of the modulation of the driving
current, both intended and unintended, to a modulation of the luminous output. This light
modulation can give rise to changes in the perception of the environment. While in some very
specific entertainment, scientific or industrial applications a change of perception due to light
modulation is desired, for most everyday applications and activities the change is detrimental
and undesired. These changes in the perception of the environment are called "temporal light
artefacts" (TLAs) and can have a large influence on the judgment of the light quality.
Moreover, the visible modulation of light can lead to a decrease in performance, increased
fatigue as well as health problems like epileptic seizures and migraine episodes [17][18] .
Different terms exist to describe the different types of TLAs that may be perceived by humans.
The term "flicker" refers to light variation that may be directly perceived by an observer.
"Stroboscopic effect" is an effect which may become visible for an observer when a moving or
rotating object is illuminated (CIE TN 006:2016 [26]).
Possible causes for light modulation of lighting equipment that may give rise to flicker or
stroboscopic effect are:
– AC supply combined with light source technology and its driver topology;
– light regulation technology of externally applied light level regulators or internal light level
regulators;
– mains voltage fluctuations caused by electrical apparatus connected to the mains
(conducted electromagnetic disturbances) or intentionally applied for mains-signalling
purposes.
Lighting products that show unacceptable flicker are considered as poor-quality lighting.
This document provides a description of an objective light flickermeter and a method for
measuring the intrinsic flicker of lighting equipment as well as testing the immunity of lighting
equipment against mains voltage fluctuations caused by electrical apparatus connected to the
mains at levels that are allowed through IEC 61000-3-3.
Flicker perception, as well as IEC 61000-3-3 and IEC 61000-4-15, the associated standards
for voltage fluctuations and the flickermeter, are based on the 60 W incandescent lamp. As a
result of the phasing out of incandescent lamps and the widespread introduction of alternative
lighting equipment technologies, a new reference lamp was considered. It has been
demonstrated that new lighting technologies are in general less but sometimes also more
sensitive to supply voltage fluctuations than the current 60 W incandescent lamp. A CIGRE
working group has assessed the impact of new lighting technologies on the existing flicker
standards [16]. For the moment, the present flicker sensitivity curve of IEC 61000-3-3 remains
as the reference. However, because of the increased diversity of sensitivity of lighting
equipment to voltage fluctuations, there is a future need for a voltage-fluctuation immunity test
specifically for lighting equipment. In this way, the full EMC approach (Figure 1) is introduced
for flicker, i.e. with a view to limiting voltage fluctuations caused by equipment connected to
the grid, and in addition to establishing a minimum level of flicker immunity of lighting
equipment against these voltage fluctuations.
This document will allow the lighting industry to gain experience in flicker immunity test
methods. Results of actual tests will be reported in a separate IEC Technical Report. Based
on the experience gained on this immunity test method, the adoption of a similar test to be
applied for IEC 61547, the immunity standard for lighting equipment, will be considered.
___________
Numbers in square brackets refer to the Bibliography.

– 8 – IEC TR 61547-1:2020 © IEC 2020
EQUIPMENT FOR GENERAL LIGHTING PURPOSES –
EMC IMMUNITY REQUIREMENTS –
Part 1: Objective light flickermeter and voltage fluctuation
immunity test method
1 Scope
This part of IEC 61547 describes an objective light flickermeter, which can be applied for the
following purposes:
– measuring the intrinsic performance of all lighting equipment without the application of
voltage fluctuations in terms of illuminance flicker; during this measurement, the lighting
equipment is supplied with a stable mains;
– testing the immunity performance of lighting equipment against (unintentional) voltage
fluctuation disturbance on the AC mains in terms of illuminance flicker; during this test a
set of defined voltage fluctuations are applied to the AC mains and the immunity of the
lighting equipment to the disturbance is determined.
Apart from the above two purposes, the immunity performance of lighting equipment can also
be tested against intentional voltage fluctuation on the AC mains arising for example from
mains signalling. This is however not described in further detail in this document.
NOTE 1 IEC 61000-4-13:2015 [24] provides guidance regarding test levels and frequencies for mains signalling.
The object of this document is to establish a common and objective reference for evaluating
the performance of lighting equipment in terms of illuminance flicker. Temporal changes in the
colour of light (chromatic flicker) are not considered in this test.
This method can be applied to lighting equipment which is within the scope of IEC technical
committee 34, such as lamps and luminaires, intended for connection to a low voltage
electricity supply. Independent auxiliaries such as drivers can also be tested by application of
a representative light source to that auxiliary.
The objective light flickermeter and voltage fluctuation immunity method described in this
document are based on the IEC 61000-3-3 standard for voltage fluctuation limits and the
flickermeter standard IEC 61000-4-15.
The objective light flickermeter described in this document can be applied to objectively
assess flicker of lighting equipment that is powered from any type of source, AC mains, DC
mains, battery fed or fed through an external light level regulator. The specific voltage
fluctuation immunity test method described in this document applies to lighting equipment
rated for 120 V AC and 230 V AC, 50 Hz and 60 Hz.
NOTE 2 The principle of the method can be applied for other nominal voltages and frequency ratings.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their
content constitutes requirements 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 61000-3-3:2013, Electromagnetic compatibility (EMC) – Part 3-3: Limits – Limitation of
voltage changes, voltage fluctuations and flicker in public low-voltage supply systems, for
equipment with rated current ≤ 16 A per phase and not subject to conditional connection
IEC 61000-4-15:2010, Electromagnetic compatibility (EMC) – Part 4-15: Testing and
measurement techniques – Flickermeter – Functional and design specifications
3 Terms, definitions, abbreviated terms and symbols
3.1 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 61000-3-3 and
IEC 61000-4-15 and the following apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1.1
flicker
perception of visual unsteadiness induced by a light stimulus the luminance or spectral
distribution of which fluctuates with time, for a static observer in a static environment
Note 1 to entry: The fluctuations of the light stimulus with time include periodic and non-periodic fluctuations and
can be induced by the source itself, the power source or other influencing factors.
[SOURCE: CIE TN 006:2016]
3.1.2
flickermeter
instrument designed to measure any quantity representative of flicker
[SOURCE: IEC 60050-614:2016, 614-01-30]
3.1.3
voltage flickermeter
instrument which is designed to measure any quantity representative of flicker resulting from
mains voltage fluctuations
Note 1 to entry: Specifications of the voltage flickermeter can be found in IEC 61000-4-15.
3.1.4
illuminance
quotient of the luminous flux dΦ incident on an element of the surface containing the point,
v
by the area dA of that element
Equivalent definition. Integral, taken over the hemisphere visible from the given point, of the
expression L ·cos θ·dΩ where L is the luminance at the given point in the various directions
v v
of the incident elementary beams of solid angle dΩ, and θ is the angle between any of these
beams and the normal to the surface at the given point
dΦ
v
EL= = ⋅⋅cosθ dΩ
vv
∫
dA 2π sr
–2
Note 1 to entry: Illuminance is expressed in lx or lm·m .

– 10 – IEC TR 61547-1:2020 © IEC 2020
[SOURCE: IEC 60050-845:1987, 845-01-38]
3.1.5
light flickermeter
instrument designed to measure flicker resulting from temporal changes in the intensity of the
light in an objective way
Note 1 to entry: The light flickermeter is based on the IEC 61000-4-15 specifications.
3.1.6
threshold of flicker irritability
maximum value of a fluctuation of luminance or of spectral distribution which gives rise to a
flicker tolerated without discomfort by a specified sample of the population
[SOURCE: IEC 60050-161:1990, 161-08-16]
3.1.7
short-term flicker indicator
P
st
measure of flicker evaluated over a specified time interval of a relatively short duration
Note 1 to entry: The duration is typically 10 min, in accordance with IEC 61000-4-15.
Note 2 to entry: The alternative term "short term flicker severity" is used in IEC 61000-3-3 and IEC 61000-4-15.
[SOURCE: IEC 60050-161:1990, 161-08-18, modified – Note 2 has been added.]
3.2 Abbreviated terms
AC alternating current
CFL compact fluorescent lamp
CIE Commission Internationale de l'Éclairage
cpm changes per minute
DC direct current
EUT equipment under test
EMC electromagnetic compatibility
Hz hertz
IEEE Institute of Electrical and Electronics Engineers
kHz kilohertz
LED light emitting diode
ms millisecond
RMS root mean square
SSL solid state lighting
V volt
W watt
3.3 Symbols
α multiplication factor
C gain of the light amplifier
A
d relative voltage change
d  relative change of the rectangular modulation of the illuminance
E
d  relative change of the 100 Hz-illuminance ripple
r
∆L instantaneous total light variation after a voltage fluctuation

∆u instantaneous total voltage variation after a voltage fluctuation

∆U total voltage variation of the half-period RMS value after a voltage fluctuation

f  mains frequency (50 Hz or 60 Hz)
f  modulation frequency
m
L light
m modulation index
% percent
pp percentage point
P instantaneous flicker sensation
inst
P short-term flicker indicator
st
LM
P
flicker metric of the illuminance of an EUT without the application of voltage
st
fluctuations and measured with a light flickermeter
LM
P I flicker metric of the illuminance of an EUT with the application of voltage fluctuations
( )
st
and measured with a light flickermeter
LM
P (C) flicker metric of the illuminance of the combination of a light source and a dimmer
st
measured with a light flickermeter
V
P flicker metric of the supply voltage measured with a voltage flickermeter
st
V
P N flicker metric of the noise level from an unmodulated supply voltage measured with a
( )
st
voltage flickermeter
s complex Laplace variable
ˆ
u amplitude of the mains voltage
u(t) mains voltage signal
u (t) output voltage of the light sensor amplifier
E
T modulation period
m
T period of time over which the illuminance is measured during application of the
test
voltage fluctuation
U half-period RMS-value
4 General
The immunity of lighting equipment to voltage fluctuations may be tested by applying specific
types and levels of voltage fluctuations to the mains, in accordance with the short-term flicker
indicator P = 1 curve for the reference incandescent lamp of 60 W specified in
st
IEC 61000-3-3. In this way, the full EMC approach is applied for flicker, i.e. voltage
fluctuations caused by equipment connected to the grid are limited by the voltage fluctuation
emission test of IEC 61000-3-3, while the level of flicker immunity of lighting equipment

– 12 – IEC TR 61547-1:2020 © IEC 2020
V
against these = 1 voltage fluctuations is tested using the method specified in this
P
st
document (see Figure 1).
V
During the test, the supply voltage is modulated with a fluctuation of = 1 which is
P
st
extracted from the threshold of the flicker irritability curve. The luminous intensity variation of
the lighting equipment is measured and recorded. A light flickermeter is applied to measure
LM
the value of the metric which is denoted by P I , which indicates that the test is carried out
( )
st
with the application of voltage fluctuations and the letter I stands for immunity. Further details
of the voltage fluctuations can be found in Table 1.
A flicker measurement can also be performed in order to determine the intrinsic flicker
performance of the lighting equipment. During this test, a stable mains source (see 6.2) is
used (i.e. no voltage fluctuations are applied). Similar to the above, the luminous intensity
variation of the lighting equipment is measured and recorded. A light flickermeter is applied to
LM
measure the value of the metric which is denoted by P .
st
NOTE In principle, flicker perfomance tests can be applied to an individual product as well as to test the flicker
performance of installations in actual applications (in-situ). However, the latter in-situ testing is much more prone
to measurement uncertainties due to various influence quantities such as ambient light, light modulations from
other light sources or daylight or moving subjects and (undefined/irregular) voltage fluctuation on the network.
LM
Therefore, P measurements are normally done at product level. The TLA performance of an actual application
st
environment of multiple light sources is generally better than the TLA performance of a single light source due to
the averaging out of the light modulation from the different light sources. Note that the flicker immunity test against
LM
voltage fluctuations ( ) cannot be performed in-situ.
P (I)
st
a) Voltage fluctuation emission test in IEC 61000-3-3, using the IEC voltage
flickermeter in IEC 61000-4-15

b) Voltage fluctuation immunity test specified in this document
Figure 1 – Full EMC approach for mains voltage fluctuations

5 Light flickermeter
For an objective assessment of flicker due to low-frequency light modulation, the flickermeter
specified in Annex A is used. Additional requirements for this light flickermeter are given in
7.3, 7.4, 7.5 and 7.6.
This light flickermeter can be applied to objectively assess the flicker of lighting equipment
that is powered from any type of source, AC mains, DC mains, battery powered or powered
through an external light level regulator. In this document, specific mains voltage disturbance
signals are given in Clause 6 for 120 V AC and 230 V AC, 50 Hz and 60 Hz networks.
6 Voltage fluctuation disturbance signal
6.1 General
The immunity test against voltage fluctuations is carried out in accordance with the test
method specified in Clause 7. The disturbances are rectangular amplitude modulations that
are applied on the AC mains.
The mains signal is amplitude modulated with rectangular signals with frequencies between
approximately 0,3 Hz and 40 Hz. For the rectangular modulated mains signal u(t), the
following Equation (1) applies:
ˆ
u( t)=u⋅sin( 2πft)⋅+1 m⋅signum ( sin( 2πf t)) (1)
{ }
m
where
ˆ
u is the amplitude of the mains voltage;
f is the mains frequency;
m is the modulation index;
signum(x) = the signum function, signum(x) = 1 for x > 0
signum(x) = 0 for x = 0
signum(x) = –1 for x < 0
f is the modulation frequency = 1/T .
m m
Furthermore, the half-period RMS value U of the unmodulated mains signal can be written as:
U = u/ˆ 2 (2)
In IEC 61000-4-15, the relative voltage change d is applied:
ˆ
d = ∆u / u = ∆U /U , (3)
for rectangular amplitude modulation with modulation frequencies < f
where
∆u is the instantaneous total voltage variation after a voltage fluctuation;
∆U is the total voltage variation of the half-period RMS value after a voltage fluctuation.
For a rectangular modulated mains signal with modulation index m the relative voltage change
d is:
– 14 – IEC TR 61547-1:2020 © IEC 2020
d = 2m. (4)
The relative voltage change (or voltage fluctuation) d is often expressed as a percentage.
An example of the parameters is shown in Figure 2.

EXAMPLE Amplitude modulated mains signal (230 V; 50 Hz). Rectangular modulation; frequency 5 Hz (600 cpm);
T = 0,2 s; modulation index m = 0,1 (relative voltage change d = 20 %).
m
Figure 2 – Illustration of the mains test signal including
a rectangular modulated voltage fluctuation (see Equation (1))
Voltage fluctuations frequencies are often expressed in terms of voltage changes per minute
(cpm). The relation between the voltage fluctuation frequency f (in Hz) and the cpm (one
m
cycle contains two changes) is:
f = cpm / 120. (5)
m
6.2 Mains signal parameters
The unmodulated test voltage level U should be set and maintained at the nominal value of
120 V or 230 V, with a tolerance of ±0,5 %.
The mains frequency f should be set and maintained with a tolerance of ±0,5 % of the nominal
value of 50 Hz or 60 Hz.
Residual fluctuations of the unmodulated test supply voltage during a test may give rise to a
V V
noise level P N that is not exactly zero. It is recommended to keep this P N level below
( ) ( )
st st
0,2. See Clause B.5 for the impact on the uncertainty of the test.
When the above mains signal parameters are achieved, it is referred to as a stable mains
source in this document.
V
NOTE In IEC 61000-3-3, the (N) level is specified to be less than 0,4 which can induce an uncertainty of 8 %
P
st
in the IEC 61000-4-15 measurement. However, in this test protocol there are many sources of uncertainty and that
V
is the reason to set a more strict (N) level tolerance.
P
st
6.3 Disturbance signal parameters and test levels
Specific test frequencies and types of modulation are specified in the IEC flickermeter
standard IEC 61000-4-15 for performance verification purposes. It is recommended to use the
test frequencies and the rectangular modulation given in IEC 61000-4-15:2010, Table 5 also
as test signals for voltage fluctuation immunity testing of lighting equipment.
The recommended specific levels of relative voltage changes and modulation frequencies to
be applied are given in Table 1. The test levels in this table are partly taken from the
flickermeter performance test specifications given in IEC 61000-4-15:2010, Table 5, and from
the test level at 8,8 Hz given in IEC 61000-4-15:2010, Table 2b. The latter frequency is the
most sensitive frequency over the frequency range of interest.
LM
V
The voltage fluctuation test levels given in Table 1 (i.e. P = 1 levels) give P I = 1 if a
( )
st
st
typical 60 W incandescent lamp is used.
V
NOTE 1 Not all 60 W incandescent lamps have exactly the same response to = 1 [15].
P
st
LM
NOTE 2 For a 60 Hz voltage source a higher deviation in P (I) at a modulation frequency of 40 Hz is observed
st
because of the cut-off frequency of the low pass filter (LPF) of the flickermeter. The tolerance for this specific point
can be increased to ±10 %.
The rectangular modulation pattern should be applied with a duty cycle of
50 % ± 2 percentage point (pp), and the transition time from one voltage level to the next
should be less than 0,5 ms. All test frequencies and level combinations will give a short-term
V
flicker value of = 1 corresponding to the threshold of the flicker irritability curve.
P
st
The duration of the voltage fluctuation applied to the EUT should be a minimum of 180 s (see
footnote c of Table 1).
– 16 – IEC TR 61547-1:2020 © IEC 2020
Table 1 – Voltage fluctuations – Test specification of voltage
fluctuations applied at input AC mains 120/230 V and 50/60 Hz
a c d f
Rectangular amplitude modulations with duty cycle of 50 %
Voltage changes Modulation Relative voltage fluctuation
per minute frequency
cpm f d = ∆U/U
m
Hz %
120 V 120 V 230 V 230 V
50 Hz 60 Hz 50 Hz 60 Hz
39 0,325 0 1,045 1,040 0,894 0,895
110 0,916 7 0,844 0,844 0,722 0,723
b b b
1 056 8,8 0,353 b 0,353 0,275 0,275
1 620 13,5 0,545 0,548 0,407 0,409
Test not Test not
e
4 000 33 1/3 3,426 required 2,343 required
Test not 4,837 Test not 3,263
e
4 800 40,0 required required
a
See Table 5 of IEC 61000-4-15:2010 and Table D1 of IEC 61000-3-3:2013.
b
See Tables 2a and 2b of IEC 61000-4-15:2010 for P = 1; the values of d = 0,252 % and d = 0,196 % are
inst
LM
increased to respectively 0,353 % and 0,275 % to give P I = 1.
( )
st
c
The duration of the voltage fluctuation and recording of the illuminance is recommended to be a minimum of
180 s (60 s for the transient response of the flickermeter’s filters and 120 s for the duration of the statistical
evaluation of the flicker level in block d, see A.2.5). First of all, the transient response of the light
flickermeter’s filters should be considered, which is dominated by the illuminance adapter (block a, see A.2.2).
The time constant of this filter is set at 10 s, reaching the 90 % of the value corresponding to the steady state
response at approximately 50 s. In addition, the evaluation period should contain an integer number of voltage
fluctuation periods. For the set of test modulation frequencies given in this table, the minimum duration to
achieve an integer number of voltage fluctuation periods in all the test cases is 120 s.
d
Recommended absolute
...