IEC 61000-3-3:2008

IEC 61000-3-3
Edition 2.0 2008-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
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

Compatibilité électromagnétique (CEM) –
Partie 3-3: Limites – Limitation des variations de tension, des fluctuations de
tension et du papillotement dans les réseaux publics d'alimentation basse
tension, pour les matériels ayant un courant assigné ≤16 A par phase et non
soumis à un raccordement conditionnel

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IEC 61000-3-3
Edition 2.0 2008-06
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
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

Compatibilité électromagnétique (CEM) –
Partie 3-3: Limites – Limitation des variations de tension, des fluctuations de
tension et du papillotement dans les réseaux publics d'alimentation basse
tension, pour les matériels ayant un courant assigné ≤16 A par phase et non
soumis à un raccordement conditionnel

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
T
CODE PRIX
ICS 33.100.10 ISBN 2-8318-9831-5

– 2 – 61000-3-3 © IEC:2008
CONTENTS
FOREWORD.3
INTRODUCTION.5
1 Scope.6
2 Normative references.6
3 Definitions.7
4 Assessment of voltage changes, voltage fluctuations and flicker .8
4.1 Assessment of a relative voltage change, "d" .8
4.2 Assessment of the short-term flicker value, P .9
st
4.2.1 Flickermeter.9
4.2.2 Simulation method.9
4.2.3 Analytical method.9
4.2.4 Use of P = 1 curve.10
st
4.3 Assessment of long-term flicker value, P .10
lt
5 Limits.10
6 Test conditions.11
6.1 General.11
6.2 Measurement accuracy.12
6.3 Test supply voltage.12
6.4 Reference impedance.12
6.5 Observation period.12
6.6 General test conditions.13
Annex A (normative) Application of limits and type test conditions
for specific equipment.18
Annex B (normative) Test conditions and procedures for measuring d voltage
max
changes caused by manual switching .25

Figure 1 – Reference network for single-phase and three-phase supplies derived
from a three-phase, four-wire supply.14
Figure 2 – Histogram evaluation of U(t).15
Figure 3 – Relative voltage change characteristic .15
Figure 4 – Curve for P =1 for rectangular equidistant voltage changes .16
st
Figure 5 – Shape factors F for double-step and ramp-voltage characteristics.16
Figure 6 – Shape factors F for rectangular and triangular voltage characteristics.17
Figure 7 – Shape factor F for motor-start voltage characteristics
having various front times .17

Table 1 – Assessment method .9
Table A.1 – Electrode parameters.23
Table A.2 – Frequency factor R related to repetition rate "r" .24

61000-3-3 © IEC:2008 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
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
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
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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 61000-3-3 has been prepared by subcommittee 77A: Low-
frequency phenomena, of IEC technical committee 77: Electromagnetic compatibility.
This second edition IEC 61000-3-3 cancels and replaces the first edition published in 1994,
amendment 1 (2001) and amendment 2 (2005). This edition constitutes a revised edition.
The document 77A/644/FDIS, circulated to the National Committees as amendment 3, led to
the publication of the new edition.

– 4 – 61000-3-3 © IEC:2008
The text of this standard is based on the first edition, its amendment 1, amendment 2 and on
the following documents:
FDIS Report on voting
77A/644/FDIS 77A/650/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
The committee has decided that the contents of this amendment and the base publication 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.
61000-3-3 © IEC:2008 – 5 –
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 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 9: Miscellaneous
Each part is further subdivided into sections which are to be published either as International
Standards or as Technical Reports.
These standards and reports will be published in chronological order and numbered
accordingly.
This part is a Product Family Standard.
The limits in this standard relate to the voltage changes experienced by consumers connected
at the interface between the public supply low-voltage network and the equipment user’s
installation. Consequently, if the actual impedance of the supply at the supply terminals of
equipment connected within the equipment user’s installation exceeds the test impedance,
it is possible that supply disturbance exceeding the limits may occur.

– 6 – 61000-3-3 © IEC:2008
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
1 Scope
This part of IEC 61000 is concerned with the limitation of voltage fluctuations and flicker
impressed on the public low-voltage system.
It specifies limits of voltage changes which may be produced by an equipment tested under
specified conditions and gives guidance on methods of assessment.
This part of IEC 61000 is applicable to electrical and electronic equipment having an input
current equal to or less than 16 A per phase, intended to be connected to public low-voltage
distribution systems of between 220 V and 250 V line to neutral at 50 Hz, and not subject to
conditional connection.
Equipment which does not comply with the limits of this part of IEC 61000 when tested with
the reference impedance Z of 6.4, and which therefore cannot be declared compliant with

ref
this part, may be retested or evaluated to show conformity with IEC 61000-3-11. Part 3-11 is
applicable to equipment with rated input current ≤75 A per phase and subject to conditional
connection.
The tests according to this part are type tests. Particular test conditions are given in annex A
and the test circuit is shown in Figure 1.
NOTE The limits in this part of IEC 61000 are based mainly on the subjective severity of flicker imposed on the
light from 230 V/60 W coiled-coil filament lamps by fluctuations of the supply voltage. For systems with nominal
voltage less than 220 V line to neutral and/or frequency of 60 Hz, the limits and reference circuit values are under
consideration.
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):1990, International Electrotechnical Vocabulary (IEV) – Chapter 161:
Electromagnetic compatibility
IEC/TR 60725, Consideration of reference impedances and public supply impedances for use
in determining disturbance characteristics of electrical equipment having a rated current
≤75 A per phase
IEC 60974-1, Arc welding equipment – Part 1: Welding power sources
IEC 61000-3-2:2005, Electromagnetic compatibility (EMC) – Part 3-2: Limits – Limits for
harmonic current emissions (equipment input current ≤16 A per phase)

61000-3-3 © IEC:2008 – 7 –
IEC 61000-3-11, Electromagnetic compatibility (EMC) – Part 3-11: Limits – Limitation of
voltage changes, voltage fluctuations and flicker in public low-voltage supply systems –
Equipment with rated current ≤75 A and subject to conditional connection
IEC 61000-4-15, Electromagnetic compatibility (EMC) – Part 4: Testing and measurement

techniques – Section 15: Flickermeter – Functional and design specifications
3 Definitions
For the purpose of this part of IEC 61000-3, the following definitions apply.
3.1
r.m.s. voltage shape, U(t)
the time function of r.m.s. voltage, evaluated as a single value for each successive half period
between zero-crossings of the source voltage (see Figure 2)
3.2
voltage change characteristic, ΔU(t)
the time function of the r.m.s. voltage change evaluated as a single value for each successive
half period between zero-crossings of the source voltage between time intervals in which the
voltage is in a steady-state condition for at least 1 s (see Figure 2)
NOTE Since this characteristic is only used for assessments using calculations, the voltage in the steady-state
condition is assumed to be constant within the measurement accuracy (see 6.2).
3.3
maximum voltage change characteristic, ΔU
max
the difference between maximum and minimum r.m.s. values of a voltage change
characteristic (see Figure 2)
3.4
steady-state voltage change, ΔU
c
the difference between two adjacent steady-state voltages separated by at least one voltage
change characteristic (see Figure 2)
NOTE Definitions 3.2 to 3.4 relate to absolute phase-to-neutral voltages. The ratios of these magnitudes to the
phase-to-neutral value of the nominal voltage (U ) of the reference network in Figure 1 are called:
n
– relative voltage change characteristic: d(t) (definition 3.2);
– maximum relative voltage change: d (definition 3.3);
max
– relative steady-state voltage change: d (definition 3.4).
c
These definitions are explained by the example in Figure 3.
3.5
voltage fluctuation
series of changes of r.m.s. voltage evaluated as a single value for each successive half-
period between zero-crossings of the source voltage
3.6
flicker
impression of unsteadiness of visual sensation induced by a light stimulus whose luminance
or spectral distribution fluctuates with time. [IEV 161-08-13]
3.7
short-term flicker indicator, P
st
the flicker severity evaluated over a short period (in minutes); P = 1 is the conventional
st
threshold of irritability
– 8 – 61000-3-3 © IEC:2008
3.8
long-term flicker indicator, P
lt
the flicker severity evaluated over a long period (a few hours) using successive P values
st
3.9
flickermeter:
an instrument designed to measure any quantity representative of flicker
NOTE Measurements are normally P and P . [IEV 161-08-14]
st lt
3.10
flicker impression time, t
f
value with a time dimension which describes the flicker impression of a voltage change
characteristic
3.11
conditional connection
connection of equipment requiring the user’s supply at the interface point to have an
impedance lower than the reference impedance Z in order that the equipment emissions
ref
comply with the limits in this part.
NOTE Meeting the voltage change limits may not be the only condition for connection; emission limits for other
phenomena such as harmonics, may also have to be satisfied.
3.12
interface point
interface between a public supply network and a user’s installation
4 Assessment of voltage changes, voltage fluctuations and flicker
4.1 Assessment of a relative voltage change, "d"
The basis for flicker evaluation is the voltage change characteristic at the terminals of
the equipment under test, that is the difference ΔU of any two successive values of the phase-
to-neutral voltages U(t ) and U(t ):
1 2
ΔU = U(t ) – U(t) (1)
1 2
The r.m.s. values U(t ), U(t ) of the voltage shall be measured or calculated. When deducing
1 2
r.m.s. values from oscillographic waveform, account should be taken of any waveform
distortion that may be present. The voltage change ΔU is due to the change of the voltage
drop across the complex reference impedance Z, caused by the complex fundamental input
current change, ΔI, of the equipment under test. ΔI and ΔI are the active and reactive parts
p q
respectively of the current change, ΔI.
ΔI = ΔI – j · ΔI = I(t ) – I(t) (2)
p q 1 2
NOTE 1 I is positive for lagging currents and negative for leading currents.
q
NOTE 2 If the harmonic distortion of the currents I(t ) and I(t ) is less than 10 %, the total r.m.s. value may be
1 2
applied instead of the r.m.s. values of their fundamental currents.
NOTE 3 For single-phase and symmetrical three-phase equipment the voltage change can, provided X is positive
(inductive), be approximated to:
ΔU = ⏐ΔI · R + ΔI · X ⏐ (3)
p q
where
ΔI and ΔI are the active and reactive parts respectively of the current change ΔI;
p q
R and X are the elements of the complex reference impedance Z (see Figure 1).
The relative voltage change is given by:
"d" = ΔU/U (4)
n
61000-3-3 © IEC:2008 – 9 –
4.2 Assessment of the short-term flicker value, P
st
The short-term flicker value P is defined in IEC 61000-4-15.
st
Table 1 shows alternative methods for evaluating P , due to voltage fluctuations of different
st
types:
Table 1 – Assessment method
Types of voltage fluctuations Methods of evaluation P
st
All voltage fluctuations
Direct measurement
(on-line evaluation)
All voltage fluctuations where U(t) is defined Simulation
Direct measurement
Voltage change characteristics according Analytical method
to Figures 5 to 7 with an occurrence rate Simulation
less than 1 per second Direct measurement
Rectangular voltage change at equal intervals Use of the P = 1 curve of Figure 4
st
4.2.1 Flickermeter
All types of voltage fluctuations may be assessed by direct measurement using a flickermeter
which complies with the specification given in IEC 61000-4-15, and is connected as described
in Clause 6 of this part. This is the reference method for application of the limits.
4.2.2 Simulation method
In the case where the relative voltage change characteristic d(t) is known, P can be
st
evaluated using a computer simulation.
4.2.3 Analytical method
value can
For voltage change characteristics of the types shown in Figures 5, 6 and 7, the P
st
be evaluated by an analytical method using equations (5) and (6).
NOTE 1 The value of P obtained using this method is expected to be within ±10 % of the result which would be
st
obtained by direct measurement (reference method).
NOTE 2 This method is not recommended if the time duration between the end of one voltage change and the
start of the next is less than 1 s.
4.2.3.1 Description of the analytical method
Each relative voltage change characteristic shall be expressed by a flicker impression time, t ,
f
in seconds:
3,2
t = 2,3 (F · d ) (5)
f max
– the maximum relative voltage change d is expressed as a percentage of the nominal
max
voltage;
– the shape factor, F, is associated with the shape of the voltage change characteristic
(see 4.2.3.2).
The sum of the flicker impression times, Σt , of all evaluation periods within a total interval of
f
the length T , in seconds, is the basis for the P evaluation. If the total time interval T is
p st p
chosen according to 6.5, it is an "observation period", and:
1/3,2
P = (Σt /T ) (6)
st f p
– 10 – 61000-3-3 © IEC:2008
4.2.3.2 Shape factor
The shape factor, F, converts a relative voltage change characteristic d(t) into a flicker
equivalent relative step voltage change (F · d ).
max
NOTE 1 The shape factor, F, is equal to 1,0 for step voltage changes.
NOTE 2 The relative voltage change characteristic may be measured directly (see Figure 1) or calculated from
the r.m.s. current of the equipment under test (see equations (1) to (4)).
The relative voltage change characteristic shall be obtained from a histogram of U(t)
(see Figure 3).
The shape factor may be deduced from Figures 5, 6 and 7, provided that the relative voltage
change characteristic matches a characteristic shown in the Figures. If the characteristics
match, proceed as follows:
– find the maximum relative voltage change d (according to Figure 3); and
max
– find the time T(ms) appropriate to the voltage change characteristic as shown in Figures 5,
6 and 7 and, using this value, obtain the required shape factor, F.
NOTE 3 Extrapolation outside the range of the Figures may lead to unacceptable errors.
4.2.4 Use of P = 1 curve
st
In the case of rectangular voltage changes of the same amplitude "d" separated by equal time
intervals, the curve of Figure 4 may be used to deduce the amplitude corresponding to P = 1
st
for a particular rate of repetition; this amplitude is called d . The P value corresponding to
lim st
the voltage change "d" is then given by P = d/d .
st lim
4.3 Assessment of long-term flicker value, P
lt
The long-term flicker value P is defined in IEC 61000-4-15 and shall be applied with the
lt
value of N = 12 (see 6.5).
It is generally necessary to assess the value of P for equipment which is normally operated
lt
for more than 30 min at a time.
5 Limits
The limits shall be applicable to voltage fluctuations and flicker at the supply terminals of the
equipment under test, measured or calculated according to Clause 4 under test conditions
described in Clause 6 and Annex A. Tests made to prove compliance with the limits are
considered to be type tests.
The following limits apply:
– the value of P shall not be greater than 1,0;
st
– the value of P shall not be greater than 0,65;
lt
– the value of d(t) during a voltage change shall not exceed 3,3 % for more than 500 ms;
– the relative steady-state voltage change, d , shall not exceed 3,3 %;
c
– the maximum relative voltage change d , shall not exceed
max
a) 4 % without additional conditions;
b) 6 % for equipment which is:
– switched manually, or
– switched automatically more frequently than twice per day, and also has either a
delayed restart (the delay being not less than a few tens of seconds), or manual
restart, after a power supply interruption.

61000-3-3 © IEC:2008 – 11 –
NOTE The cycling frequency will be further limited by the P and P limit. For example: a d of 6 % producing a
st lt max
rectangular voltage change characteristic twice per hour will give a P of about 0,65.
lt
c) 7 % for equipment which is
– attended whilst in use (for example: hair dryers, vacuum cleaners, kitchen
equipment such as mixers, garden equipment such as lawn mowers, portable tools
such as electric drills), or
– switched on automatically, or is intended to be switched on manually, no more than
twice per day, and also has either a delayed restart (the delay being not less than a
few tens of seconds) or manual restart, after a power supply interruption.
In the case of equipment having several separately controlled circuits in accordance with 6.6,
limits b) and c) shall apply only if there is delayed or manual restart after a power supply
interruption; for all equipment with automatic switching which is energised immediately on
restoration of supply after a power supply interruption, limits a) shall apply; for all equipment
with manual switching, limits b) or c) shall apply depending on the rate of switching.
P and P requirements shall not be applied to voltage changes caused by manual switching.
st lt
The limits shall not be applied to voltage changes associated with emergency switching or
emergency interruptions.
6 Test conditions
6.1 General
Tests need not be made on equipment which is unlikely to produce significant voltage
fluctuations or flicker.
It may be necessary to determine, by examination of the circuit diagram and specification of
the equipment and by a short functional test, whether significant voltage fluctuations are likely
to be produced.
For voltage changes caused by manual switching, equipment is deemed to comply without
further testing if the maximum r.m.s. input current (including inrush current) evaluated over
each 10 ms half-period between zero-crossings does not exceed 20 A, and the supply current
after inrush is within a variation band of 1,5 A.
If measurement methods are used, the maximum relative voltage change d caused by
max
manual switching shall be measured in accordance with Annex B.
Tests to prove the compliance of the equipment with the limits shall be made using the test
circuit in Figure 1.
The test circuit consists of:
– the test supply voltage (see 6.3);
– the reference impedance (see 6.4);
– the equipment under test (see Annex A);
– if necessary, a flickermeter (see IEC 61000-4-15).
The relative voltage change d(t) may be measured directly or derived from the r.m.s. current
as described in 4.1. To determine the P value of the equipment under test, one of the
st
methods described in 4.2 shall be used. In case of doubt, the P shall be measured using
st
the reference method with a flickermeter.
NOTE If balanced multiphase equipment is tested, it is acceptable to measure only one of the three line-to-neutral
vol t a ges .
– 12 – 61000-3-3 © IEC:2008
6.2 Measurement accuracy
The magnitude of the current shall be measured with an accuracy of ±1 % or better. If instead
of active and reactive current the phase angle is used, its error shall not exceed ±2°.
The relative voltage change "d" shall be determined with a total accuracy better than ±8 %
with reference to the maximum value d . The total impedance of the circuit, excluding the
max
appliance under test, but including the internal impedance of the supply source, shall be equal
to the reference impedance. The stability and tolerance of this total impedance shall be
adequate to ensure that the overall accuracy of ±8 % is achieved during the whole
assessment procedure.
NOTE The following method is not recommended where the measured values are close to the limits.
When the source impedance is not well defined, for example where the source impedance is
subject to unpredictable variations, an impedance having resistance and inductance equal to
the reference impedance may be connected between the supply and the terminals of the
equipment under test. Measurements can then be made of the voltages at the source side of
the reference impedance and at the equipment terminals. In that case, the maximum relative
voltage change, d , measured at the supply terminals shall be less than 20 % of the
max
measured at the equipment terminals.
maximum value d
max
6.3 Test supply voltage
The test supply voltage (open-circuit voltage) shall be the rated voltage of the equipment. If a
voltage range is stipulated for the equipment, the test voltage shall be 230 V single-phase or
400 V three-phase. The test voltage shall be maintained within ±2 % of the nominal value.
The frequency shall be 50 Hz ± 0,5 %.
The percentage total harmonic distortion of the supply voltage shall be less than 3 %.
Fluctuations of the test supply voltage during a test may be neglected if the P value is less
st
than 0,4. This condition shall be verified before and after each test.
6.4 Reference impedance
For equipment under test the reference impedance, Z according to IEC 60725, is a con-
ref,
ventional impedance used in the calculation and measurement of the relative voltage change
"d", and the P and P values.
st lt
The impedance values of the various elements are given in Figure 1.
6.5 Observation period
The observation period, T , for the assessment of flicker values by flicker measurement,
p
flicker simulation, or analytical method shall be:
– for P , T = 10 min;
st p
– for P , T = 2 h.
lt p
The observation period shall include that part of the whole operation cycle in which the
equipment under test produces the most unfavourable sequence of voltage changes.
For the assessment of P , the cycle of operation shall be repeated continuously, unless
st
stated otherwise in Annex A. The minimum time to restart the equipment shall be included in
this observation period when testing equipment that stops automatically at the end of a cycle
of operation which lasts for less than the observation period.

61000-3-3 © IEC:2008 – 13 –
For P assessment, the cycle of operation shall not be repeated, unless stated otherwise in
lt
Annex A, when testing equipment with a cycle of operation of less than 2 h and which is not
normally used continuously.
NOTE For example, in the case of equipment with a cycle of operation lasting 45 min, five consecutive P values
st
will be measured during a total period of 50 min, and the remaining seven P values in the 2 h observation period
st
will be deemed to be zero.
6.6 General test conditions
The test conditions for the measurement of voltage fluctuations and flicker are given below.
For equipment not mentioned in Annex A, controls or automatic programs shall be set to
produce the most unfavourable sequence of voltage changes, using only those combinations
of controls and programmes which are mentioned by the manufacturer in the instruction
manual, or are otherwise likely to be used. Particular test conditions for equipment not
included in Annex A are under consideration.
The equipment shall be tested in the condition in which it is supplied by the manufacturer.
Preliminary operation of motor drives may be needed before the tests to ensure that results
corresponding to those of normal use are obtained.
NOTE Operating conditions include mechanical and/or electrical loading conditions.
For motors, locked-rotor measurements may be used to determine the largest r.m.s. voltage
change, d , occurring during motor starting.
max
For equipment having several separately controlled circuits, the following conditions apply:
– each circuit shall be considered as a single item of equipment if it is intended to be used
independently, provided that the controls are not designed to switch at the same instant;
– if the control of separate circuits are designed to switch simultaneously, the group of
circuits so controlled are considered as a single item of equipment.
For control systems regulating part of a load only, the voltage fluctuations produced by each
variable part of the load alone shall be considered.
Detailed type test conditions for some equipment are given in Annex A.

– 14 – 61000-3-3 © IEC:2008
EUT equipment under test
M measuring equipment
S supply source consisting of the supply voltage generator G and reference impedance Z with the elements:
R = 0,24 Ω; jX = 0,15 Ω at 50 Hz;
A A
R = 0,16 Ω; jX = 0,10 Ω at 50 Hz.
N N
The elements include the actual generator impedance.
When the source impedance is not well defined, see 6.2.
G voltage source in accordance with 6.3.
NOTE In general, three-phase loads are balanced, and R and X can be neglected, as there is no current in the
N N
neutral wire.
Figure 1 – Reference network for single-phase and three-phase supplies
derived from a three-phase, four-wire supply

61000-3-3 © IEC:2008 – 15 –
U(t)
ΔU
c
ΔU(t)
ΔU
max
t t
1 t t
2 3
10 ms
IEC  047/01
Figure 2 – Histogram evaluation of U(t)

U(t)
U
n
d
c
d(t)
d
max
t
t t t
1 2 3
IEC  048/01
Figure 3 – Relative voltage change characteristic

– 16 – 61000-3-3 © IEC:2008
NOTE 1 200 voltage changes per minute give 10 Hz flicker.
Figure 4 – Curve for P =1 for rectangular equidistant voltage changes
st
Figure 5 – Shape factors F for double-step and ramp-voltage characteristics

61000-3-3 © IEC:2008 – 17 –
Figure 6 – Shape factors F for rectangular and triangular voltage characteristics

NOTE T = t – t , T = t – t (see Figure 3).
t 3 2 f 2 1
Figure 7 – Shape factor F for motor-start voltage characteristics
having various front times
– 18 – 61000-3-3 © IEC:2008
Annex A
(normative)
Application of limits and type test conditions
for specific equipment
A.1 Test conditions for cookers
For cookers designed for use in domestic premises, the evaluation of P shall not be required.
lt
The tests of P shall be performed at steady-state temperature conditions, unless stated
st
otherwise.
Each heater shall be tested separately as follows.
A.1.1 Hotplates
Hotplates shall be tested using standard saucepans with diameter, height and water quantity
as follows:
Diameter of
Height of the pot Quantity of water
the hotplate
(mm) (mm) (g)
145 about 140 1 000 ± 50
180 about 140 1 500 ± 50
220 about 120 2 000 ± 50
Possible losses by evaporation have to be compensated for during the time of measurement.
In all of the following tests the hotplate shall comply with the limits given in Clause 5.
a) Boiling temperature range: set the control to the position where the water just boils. The
test is made five times and the mean value of the test results calculated.
b) Frying temperature range: fill the pot, without a lid, with silicone oil to 1,5 times the
quantity of water shown in the Table. Set the control to a temperature of 180 °C measured
by a thermocouple in the geometric centre of the oil.
c) Total range of power settings: the total power range shall be checked continuously during
a 10 min observation period. If control switches have discrete stages, test all stages up to
a maximum of 20 stages. If there are no discrete stages, divide the total range into 10
equally spaced steps. The measurements shall then be made starting at the highest power
stage.
A.1.2 Baking ovens
The oven shall be tested empty with the door closed. Adjust the control so that a
thermocouple fixed in the geometric centre measures a mean temperature of 220 °C for con-
ventional ovens and 200 °C for hot air oven.
A.1.3 Grills
The grill shall be tested empty with the door closed, if not otherwise stated by the
manufacturer. If a control is available it shall be set to the lowest, the medium and the highest
setting for grilling operation; and the worst result recorded.

61000-3-3 © IEC:2008 – 19 –
A.1.4 Baking oven/grill combinations
The oven/grill combination shall be tested empty with the door closed. Adjust the control so
that a thermocouple fixed in the geometric centre measures a mean temperature of 250 °C,
or that available temperature closest to this value.
A.1.5 Microwave ovens
The microwave oven or the microwave function of a combination oven shall be tested at the
lowest, the medium and a third stage which is the highest adjustable power less than or equal
to 90 % of the maximum power. Load the oven with a glass bowl containing 1 000 ± 50 g of
water.
A.2 Test conditions for lighting and similar equipment
The following test conditions shall apply to equipment with a primary function of generating
and/or regulating and/or distributing optical radiation by means of incandescent or discharge
lamps or LEDs.
Such equipment shall be tested with a lamp of that power for which the equipment is rated.
If lighting equipment includes more than one lamp, all lamps shall be in use.
P and P evaluations are required only for lighting equipment which is likely to produce
st lt
flicker; for example: disco lighting and automatically regulated equipment.
No limits shall apply to lamps.
Incandescent lamp luminaires with ratings less than or equal to 1 000 W and discharge lamp
luminaires with ratings less than or equal to 600 W, are deemed to comply with the d limits
max
in this standard and are not required to be tested. Luminaires with higher ratings, which
cannot comply with this part of IEC 61000, shall be subject to conditional connection in
accordance with IEC 61000-3-11.
Ballasts are deemed to be part of luminaires and are not required to be tested.
A.3 Test conditions for washing machines
The washing machine shall be tested during a complete laundry program incorporating the
normal wash-cycle, filled with the rated load of double hemmed, pre-washed cotton cloths,
2 2
size approximately 70 cm × 70 cm, dry weight from 140 g/m to 175 g/m .
The temperature of the fill water shall be:
• 65 °C ± 5 °C for washing machines without heater elements and intended for connection
to a hot water supply;
• 15 °C +10°C, – 5 °C for other washing machines.
For washing machines with a programmer, the 60 °C cotton programme without pre-wash, if
available, shall be used, otherwise the regular wash programme without pre-wash shall be
used. If the washing machine contains heating elements which are not controlled by the
programmer, the water shall be heated to 65 °C ± 5 °C before starting the first wash period.
If the washing machine contains heating elements and does not incorporate a programmer,
the water shall be heated to 90 °C ± 5 °C or low
...