IEC 60669-2-3:2024

IEC 60669-2-3 ®
Edition 4.0 2024-03
EXTENDED VERSION
INTERNATIONAL
STANDARD
colour
inside
This extended version of IEC 60669-2-3:2024 includes the content of the references made to
IEC 60669-1:2017
Switches for household and similar fixed electrical installations –
Part 2-3: Particular requirements – Time-delay switches (TDS)
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IEC 60669-2-3 ®
Edition 4.0 2024-03
EXTENDED VERSION
INTERNATIONAL
STANDARD
colour
inside
This extended version of IEC 60669-2-3:2024 includes the content of the references made to
IEC 60669-1:2017
Switches for household and similar fixed electrical installations –
Part 2-3: Particular requirements – Time-delay switches (TDS)
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 29.120.40 ISBN 978-2-8322-8541-1

– 2 – IEC 60669-2-3:2024 EXV © IEC 2024

CONTENTS
FOREWORD . 7
1 Scope . 10
2 Normative references . 11
3 Terms and definitions . 13
4 General requirements . 18
5 General remarks on tests . 18
5.101 Incorporated hand-operated device . 21
5.102 Operated by hand . 21
5.103 Control and switching circuits without common point . 21
6 Ratings . 21
6.1 Rated voltage . 21
6.2 Rated current . 21
6.3 Preferred combinations of number of poles and ratings . 22
6.101 Rated control voltage . 22
7 Classification . 23
8 Marking . 24
8.1 General . 24
8.2 Symbols . 25
8.3 Visibility of markings . 27
8.4 Marking on terminals for phase conductors . 27
8.5 Marking on terminals for neutral and earth conductors . 28
8.6 Marking of the switch position . 28
8.7 Additional requirements for marking . 29
8.8 Durability . 29
9 Checking of dimensions . 29
10 Protection against electric shock . 29
10.1 Prevention of access to live parts. 29
10.2 Requirements for operating parts . 30
10.3 Requirements for accessible metal parts . 30
10.4 Requirements for insulation of the mechanism . 31
10.5 Requirements for insulation of the mechanism with respect to the
surrounding environment . 31
10.6 Requirements for switches operated indirectly . 31
10.7 Requirements for switches with replaceable pull cord . 32
11 Provision for earthing . 32
11.1 General . 32
11.2 Earthing terminals . 32
11.3 Requirements for surface-type switches . 32
11.4 Test for earthing connection . 32
12 Terminals . 33
12.1 General . 33
12.2 Terminals with screw clamping for external copper conductors . 33
12.3 Screwless terminals for external copper conductors . 39
13 Constructional requirements . 44
13.1 Mechanical requirements for insulating means . 44
13.2 Installation requirements . 45

13.3 Fixing of covers, cover plates and actuating members . 46
13.4 Openings in normal use . 47
13.5 Attachment of knobs . 47
13.6 Mounting means . 48
13.7 Combination of switches . 48
13.8 Accessories combined with switches . 48
13.9 Surface-type switches having an IP code higher than IP20 . 48
13.10 Installation in a box . 49
13.11 Connection of a second current-carrying conductor . 49
13.12 Inlet openings . 49
13.13 Provision for back entry from a conduit . 50
13.14 Switch provided with membranes or the like for inlet openings . 51
13.15 Requirements for membranes in inlet openings . 51
13.16 Pilot light units . 52
13.101 Reset function . 52
13.102 Transformers intended for SELV circuits . 52
14 Mechanism . 52
14.1 Indication of the position . 52
14.2 Rest and intermediate position . 52
14.3 Undue arcing . 52
14.4 Making and breaking . 52
14.5 Action of the mechanism without cover or cover plate . 53
14.6 Pull force for cord-operated switches . 53
14.101 Hand-operated device with position indicator . 53
15 Resistance to ageing, protection provided by enclosures of switches and
resistance to humidity . 53
15.1 Resistance to ageing . 53
15.2 Protection provided by enclosures of switches . 54
15.2.1 General . 54
15.2.2 Protection against access to hazardous parts and against harmful
effects due to ingress of solid foreign objects . 54
15.2.3 Protection against harmful effects due to ingress of water . 55
15.3 Resistance to humidity . 56
16 Insulation resistance and electric strength . 57
16.1 General . 57
16.2 Test for measuring the insulation resistance . 57
16.3 Electric strength test . 59
17 Temperature rise . 61
17.1 General . 61
17.2 Switches incorporating pilot lights . 62
18 Making and breaking capacity . 63
18.1 General . 63
18.2 Overload . 63
18.3 Overload test with filament lamps . 64
19 Normal operation . 65
19.1 Test for switches intended for inductive loads . 65
19.2 Test for switches intended for externally ballasted lamp loads . 68
19.3 Test for switches intended for self ballasted lamp loads . 70
19.101 TDS control voltage test . 73

– 4 – IEC 60669-2-3:2024 EXV © IEC 2024

19.102 TDS delay time accuracy . 73
19.103 TDS delay after revert operation . 73
20 Mechanical strength . 74
20.1 General . 74
20.2 Pendulum hammer test . 74
20.3 Test on the main parts of surface-type switches . 77
20.4 Screwed glands . 77
20.5 Covers, cover plates or actuating members – accessibility to live parts . 77
20.5.1 General . 77
20.5.2 Verification of the non-removal of covers, cover plates or actuating
members . 77
20.5.3 Verification of the removal of covers, cover plates or actuating members. 78
20.6 Covers, cover plates or actuating members – accessibility to non-earthed
metal parts separated from live parts . 78
20.7 Covers, cover plates or actuating members – accessibility to insulating
parts, earthed metal parts, the live parts of SELV ≤ 25 V AC and 60 V DC or
metal parts separated from live parts . 78
20.8 Covers, cover plates or actuating members – application of gauges . 78
20.9 Grooves, holes and reverse tapers . 79
20.10 Additional test for cord-operated switch . 79
21 Resistance to heat . 79
21.1 General . 79
21.2 Basic heating test . 80
21.3 Ball-pressure test on parts of insulating material necessary to retain current-
carrying parts and parts of the earthing circuit in position . 80
21.4 Ball-pressure test on parts of insulating material not necessary to retain
current-carrying parts and parts of the earthing circuit in position. 80
22 Screws, current-carrying parts and connections . 81
22.1 General . 81
22.2 Correct insertion of screws . 81
22.3 Contact pressure of electrical connections . 82
22.4 Screws and rivets used both as electrical and mechanical connections . 82
22.5 Material of current-carrying parts . 82
22.6 Contacts subjected to sliding actions . 83
22.7 Thread-forming and thread-cutting screws . 83
23 Creepage distances, clearances and distances through sealing compound . 83
23.1 General . 83
23.2 Insulating compound . 87
23.101 Control circuits for connections to a SELV . 87
23.102 Use of enamel wires . 87
24 Resistance of insulating material to abnormal heat, to fire and to tracking . 87
24.1 Resistance to abnormal heat and to fire . 87
24.2 Resistance to tracking . 88
25 Resistance to rusting . 89
26 EMC requirements . 89
26.1 Immunity . 89
26.2 Emission . 89
101 Abnormal operation of the control circuit . 89

Annex A (normative) Additional requirements for switches having facilities for the
outlet and retention of flexible cables . 110
Annex B (informative) Changes planned for the future in order to align IEC 60669-1
with the requirements of IEC 60998 (all parts), IEC 60999 (all parts) and IEC 60228 . 113
Annex C (informative) Circuit development (19.3) . 114
C.1 Rationale . 114
C.2 I and I t for normal operation tests . 114
peak
C.2.1 General . 114
C.2.2 Switching a single lamp . 114
C.2.3 Switching multiple lamps . 116
Annex D (informative) Additional requirements for insulation-piercing terminals . 118
Annex E (informative) Additional requirements and tests for switches intended to be
used at a temperature lower than −5 °C . 128
Bibliography . 130

Figure 1 – Pillar terminals . 91
Figure 2 – Screw head terminals and stud terminals . 93
Figure 3 – Saddle terminals . 93
Figure 4 – Lug terminals . 94
Figure 5 – Mantle terminals. 95
Figure 6 – Thread-forming screw . 95
Figure 7 – Thread-cutting screw . 95
Figure 8 – Classification according to connections . 96
Figure 9 – Test apparatus for checking damage to conductors . 97
Figure 10 – Information for deflection test . 98
Figure 11 – Circuit diagrams for making and breaking capacity and normal operation . 99
Figure 12 – Circuit diagrams for testing switches . 100
Figure 13 – Arrangement for test on cover-plates . 100
Figure 14 – Gauge (thickness: about 2 mm) for the verification of the outline of covers,
cover-plates or actuating members . 101
Figure 15 – Example of application of the gauge of Figure 14 on covers fixed without
screws on a mounting surface or supporting surface . 102
Figure 16 – Examples of applications of the gauge of Figure 14 in accordance with the

requirements of 20.8 . 103
Figure 17 – Gauge for verification of grooves, holes and reverse tapers . 104
Figure 18 – Sketch showing the direction of application of the gauge of Figure 17 . 104
Figure 19 – Ball-pressure apparatus . 105
Figure 20 – Determining parts of insulating material to be tested – Diagrammatic
representation (see 24.1) . 105
Figure 21 – Test wall in accordance with the requirements of 15.2.3 . 106
Figure 22 – Direction for the conductor pull of 30 N for 1 min . 108
Figure 23 – Examples of membranes and grommets . 109
Figure C.1 – 120 V 15 W (LT spice model) . 115
Figure C.2 – 230 V 15 W (LT spice model) . 116
Figure C.3 – Model for multiple lamp loads . 117
Figure C.4 – I and I t for multiple lamp loads . 117
peak
– 6 – IEC 60669-2-3:2024 EXV © IEC 2024

Figure D.1 − Example of insulation-piercing terminals . 126
Figure D.2 – Example of test-points . 126
Figure D.3 – Temperature cycle for the voltage drop test of 12.4.11 . 127

Table 1 – Number of specimens needed for the tests . 20
Table 2 – Relationship between rated current of the switch and rated power of the SBL
circuit . 22
Table 3 – Preferred combinations of numbers of poles and ratings . 22
Table 4 – Relationship between rated currents and connectable cross-sectional areas
of copper conductors . 33
Table 5 – Tightening torque for the verification of the mechanical strength of screw-
type terminals . 35
Table 6 – Test values for flexion and pull out for copper conductors . 36
Table 7 – Test values for pulling out test . 37
Table 8 – Relationship between rated currents and connectable cross-sectional areas
of copper conductors for screwless terminals . 39
Table 9 – Test current for the verification of electrical and thermal stresses in normal
use of screwless terminals . 42
Table 10 – Cross-sectional areas of rigid copper conductors for deflection test of
screwless terminals . 44
Table 11 – Deflection test forces . 44
Table 12 – Forces to be applied to covers, cover-plates or actuating members whose
fixing is not dependent on screws . 47
Table 13 – External cable diameter limits for surface type switches . 50
Table 14 – Points of application of the test voltage for the verification of insulation
resistance and electric strength . 57
Table 15 – Test voltage, points of application and minimum values of insulating
resistance for the verification of electric strength . 60
Table 16 – Temperature-rise test currents and cross-sectional areas of copper
conductors . 61
Table 17 – Fractions of total number of operations. 64
Table 18 – Number of operations for normal operation test . 66
Table 19 – Values for I and I t depending on the type of distribution system . 71
peak
Table 20 – Calculated circuit parameters . 71
Table 21 – Height of fall for impact test . 75
Table 22 – Torque for the verification of the mechanical strength of glands . 77
Table 23 – Creepage distances, clearances and distances through insulating sealing
compound . 84
Table A.1 – Limits of external dimensions of flexible cables . 111
Table C.1 – Lamp . 114
Table D.1 – Specimens needed for Clause 12 for insulation-piercing terminals (IPTs) . 119
Table D.2 – Relationship between rated currents and connectable cross-sectional
areas of copper conductors for insulation-piercing terminals . 121
Table D.3 – Test current for the verification of electrical and thermal stresses in
normal use of insulation-piercing terminals . 125

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SWITCHES FOR HOUSEHOLD AND SIMILAR FIXED
ELECTRICAL INSTALLATIONS –
Part 2-3: Particular requirements –
Time-delay switches (TDS)
FOREWORD
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2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
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9) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
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This extended version (EXV) of the official IEC Standard provides the user with the
comprehensive content of the Standard.
made to IEC 60669-1:2017.
The specific content of IEC 60669-2-3:2024 is displayed on a blue background.

– 8 – IEC 60669-2-3:2024 EXV © IEC 2024

IEC 60669-2-3 has been prepared by subcommittee 23B: Plugs, socket-outlets and switches,
of IEC technical committee 23: Electrical accessories. It is an International Standard.
This fourth edition cancels and replaces the third edition published in 2006. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) Revision of the present edition with reference to IEC 60669-1:2017 (Edition 4);
b) Introduction of a revision to Annex E "Additional requirements and tests for switches
intended to be used at a temperature lower than −5 °C".
The text of this International Standard is based on the following documents:
Draft Report on voting
23B/1487/FDIS 23B/1501/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement,
available at www.iec.ch/members_experts/refdocs. The main document types developed by
IEC are described in greater detail at www.iec.ch/publications.
This part of IEC 60669-2 is to be used in conjunction with IEC 60669-1:2017. It lists the
changes necessary to convert that standard into a specific standard for time-delay switches.
When a particular subclause of IEC 60669-1:2017 is not mentioned in this document, that
subclause applies as far as reasonable.
In this document, the following print types are used:
– requirements proper: in roman type;
– test specifications: in italic type;
– notes: in smaller roman type.
Subclauses, figures or tables which are additional to those in IEC 60669-1:2017 are
numbered starting from 101.
A list of all parts of IEC 60669 series, under the general title Switches for household and
similar fixed electrical installations, 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 webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn, or
• revised.
IMPORTANT – The "colour inside" logo on the cover page of this document 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.
– 10 – IEC 60669-2-3:2024 EXV © IEC 2024

SWITCHES FOR HOUSEHOLD AND SIMILAR FIXED
ELECTRICAL INSTALLATIONS –
Part 2-3: Particular requirements –
Time-delay switches (TDS)
1 Scope
This part of IEC 60669 applies to time-delay switches (hereinafter referred to as TDS) with a
rated voltage not exceeding 440 V AC and a rated current not exceeding 63 A, intended for
household and similar fixed electrical installations, either indoors or outdoors, operated by
hand and/or by remote control. For the control circuit, the rated control voltage does not
exceed 440 V AC or 220 V DC.
TDS are provided with a time-delay device operated by mechanical, thermal, pneumatic,
hydraulic or electrical means or by a combination of them.
Electronic TDS are within the scope of IEC 60669-2-1 but not of this document.
TDS including only passive components such as resistors, capacitors, positive temperature
coefficient (PTC) and negative temperature coefficient (NTC) components and printed circuit
boards are not considered to be electronic TDS.
For switches provided with screwless terminals, the rated current is limited to 16 A.
NOTE 1 The rated current is limited to 16 A for switches provided with insulation piercing terminals (IPT’s)
according to Annex D.
Switches covered by this document are, where applicable, intended for the control in normal
use of all of the following loads:
– a circuit for a tungsten filament lamp load;
– a circuit for an externally ballasted lamp load (for example LED, CFL, fluorescent lamp
load);
– a circuit for a self ballasted lamp load (for example LEDi or CFLi);
– a circuit for a substantially resistive load with a power factor not less than 0,95;
– a single phase circuit for motor load with a rated current not exceeding 3 A at 250 V
(750 VA) and 4,5 A at 120 V (540 VA) and a power factor not less than 0,6. This applies to
both switches rated not less than 10 A that have not undergone additional tests and to
momentary switches rated not less than 6 A that have not undergone additional tests.
NOTE 2 In the following country the suitability of a switch intended to control the inrush current of a motor shall
be tested: AU.
This document also applies to boxes for switches, with the exception of mounting boxes for
flush-type switches.
NOTE 3 General requirements for boxes for flush-type switches are given in IEC 60670-1.
It also applies to switches such as
– switches incorporating pilot lights;
– electromagnetic remote control switches (particular requirements are given in
IEC 60669-2-2);
– switches incorporating a time-delay device (particular requirements are given in
IEC 60669-2-3);
– combinations of switches and other functions (with the exception of switches combined
with fuses);
– electronic switches (particular requirements are given in IEC 60669-2-1);
– switches having facilities for the outlet and retention of flexible cables (see Annex A);
– isolating switches (particular requirements are given in IEC 60669-2-4);
– switches and related accessories for use in home and building electronic systems
(particular requirements are given in IEC 60669-2-5);
– firemen’s switches (particular requirements are given in IEC 60669-2-6).
Switches complying with this document are suitable for use at ambient temperatures not
normally exceeding +40 °C, but their average over a period of 24 h does not exceed +35 °C,
with a lower limit of the ambient air temperature of –5 °C.
NOTE 4 For lower temperatures see Annex E.
Switches complying with this document are suitable only for incorporation in equipment in
such a way and in such a place that it is unlikely that the surrounding ambient temperature
exceeds +35 °C.
In locations where special conditions prevail, such as in ships, vehicles and the like and in
hazardous locations, for example where explosions are liable to occur, special construction
and/or additional requirements may be required.
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 60038:2009, IEC standard voltages
IEC 60068-2-75:2014, Environmental testing – Part 2-75: Tests – Test Eh: Hammer tests
IEC 60112:2009, Method for the determination of the proof and the comparative tracking
indices of solid insulating materials
IEC 60212:2010, Standard conditions for use prior to and during the testing of solid electrical
insulation materials
IEC 60227-5:2011, Polyvinyl chloride insulated cables of rated voltages up to and including
450/750 V – Part 5: Flexible cables (cords)
IEC 60228:2004, Conductors of insulated cables
IEC 60245-4:2011, Rubber insulated cables – Rated voltages up to and including 450/750 V –
Part 4: Cords and flexible cables
IEC 60317 (all parts), Specifications for particular types of winding wires
IEC 60417, Graphical symbols for use on equipment (available from: http://www.graphical-
symbols.info/equipment)
– 12 – IEC 60669-2-3:2024 EXV © IEC 2024

IEC 60445:2021, Basic and safety principles for man-machine interface, marking and
identification – Identification of equipment terminals, conductor terminations and conductors
IEC 60529:1989, Degrees of protection provided by enclosures (IP Code)
IEC 60529:1989/AMD1:1999
IEC 60529:1989/AMD2:2013
IEC 60664-1:2020, Insulation coordination for equipment within low-voltage supply systems –
Part 1: Principles, requirements and tests
IEC 60664-3:2016, Insulation coordination for equipment within low-voltage systems – Part 3:
Use of coating, potting or moulding for protection against pollution
IEC 60669-1:2017, Switches for household and similar fixed electrical installations – Part 1:
General requirements
IEC 60669-2-1:2002, Switches for household and similar fixed electrical installations –
Part 2-1: Particular requirements – Electronic switches
IEC 60669-2-1:2002/AMD1:2008
IEC 60669-2-1:2002/AMD2:2015
IEC 60695-2-10:2000, Fire hazard testing – Part 2-10: Glowing/hot-wire based test methods –
Glow-wire apparatus and common test procedure
IEC 60695-2-11:2014, Fire hazard testing – Part 2-11: Glowing/hot-wire based test methods –
Glow-wire flammability test method for end-products (GWEPT)
IEC 60998-1:2002, Connecting devices for low-voltage circuits for household and similar
purposes – Part 1: General requirements
IEC 60998-2-1, Connecting devices for low-voltage circuits for household and similar
purposes – Part 2-1: Particular requirements for connecting devices as separate entities with
screw-type clamping units
IEC 60998-2-2, Connecting devices for low-voltage circuits for household and similar
...

IEC 60669-2-3 ®
Edition 4.0 2024-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Switches for household and similar fixed electrical installations –
Part 2-3: Particular requirements – Time-delay switches (TDS)

Interrupteurs pour installations électriques fixes domestiques et analogues –
Partie 2-3 : Exigences particulières – Interrupteurs temporisés (minuteries)
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IEC 60669-2-3 ®
Edition 4.0 2024-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Switches for household and similar fixed electrical installations –

Part 2-3: Particular requirements – Time-delay switches (TDS)

Interrupteurs pour installations électriques fixes domestiques et analogues –

Partie 2-3 : Exigences particulières – Interrupteurs temporisés (minuteries)

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.120.40  ISBN 978-2-8322-8322-6

– 2 – IEC 60669-2-3:2024 © IEC 2024
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 6
4 General requirements . 7
5 General remarks on tests . 7
6 Ratings . 8
7 Classification . 8
8 Marking . 9
9 Checking of dimensions . 10
10 Protection against electric shock . 10
11 Provision for earthing . 10
12 Terminals . 10
13 Constructional requirements . 11
14 Mechanism . 11
15 Resistance to ageing, protection provided by enclosures of switches and
resistance to humidity . 11
16 Insulation resistance and electric strength . 11
17 Temperature rise . 12
18 Making and breaking capacity . 12
19 Normal operation . 13
20 Mechanical strength . 14
21 Resistance to heat . 14
22 Screws, current-carrying parts and connections . 14
23 Creepage distances, clearances and distances through sealing compound . 15
24 Resistance of insulating material to abnormal heat, to fire and to tracking . 16
25 Resistance to rusting . 16
26 EMC requirements . 17
Annexes . 18
Annex B (informative) Changes planned for the future in order to align IEC 60669-1
with the requirements of IEC 60998 (all parts), IEC 60999 (all parts) and IEC 60228 . 19
Annex E (informative) Additional requirements and tests for switches intended to be
used at a temperature lower than −5 °C . 20
Bibliography . 21

Table 1 – Number of specimens needed for the tests . 7
Table 15 – Test voltage, points of application and minimum values of insulating
resistance for the verification of electric strength . 12
Table 23 – Creepage distances, clearances and distances through insulating sealing
compound . 15

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SWITCHES FOR HOUSEHOLD AND SIMILAR FIXED
ELECTRICAL INSTALLATIONS –
Part 2-3: Particular requirements –
Time-delay switches (TDS)
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) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC takes no position concerning the evidence, validity or applicability of any claimed patent rights in
respect thereof. As of the date of publication of this document, IEC had not received notice of (a) patent(s), which
may be required to implement this document. However, implementers are cautioned that this may not represent
the latest information, which may be obtained from the patent database available at https://patents.iec.ch. IEC
shall not be held responsible for identifying any or all such patent rights.
IEC 60669-2-3 has been prepared by subcommittee 23B: Plugs, socket-outlets and switches,
of IEC technical committee 23: Electrical accessories. It is an International Standard.
This fourth edition cancels and replaces the third edition published in 2006. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) Revision of the present edition with reference to IEC 60669-1:2017 (Edition 4);
b) Introduction of a revision to Annex E "Additional requirements and tests for switches
intended to be used at a temperature lower than −5 °C".

– 4 – IEC 60669-2-3:2024 © IEC 2024
The text of this International Standard is based on the following documents:
Draft Report on voting
23B/1487/FDIS 23B/1501/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
This part of IEC 60669-2 is to be used in conjunction with IEC 60669-1:2017. It lists the changes
necessary to convert that standard into a specific standard for time-delay switches.
When a particular subclause of IEC 60669-1:2017 is not mentioned in this document, that
subclause applies as far as reasonable.
In this document, the following print types are used:
– requirements proper: in roman type;
– test specifications: in italic type;
– notes: in smaller roman type.
Subclauses, figures or tables which are additional to those in IEC 60669-1:2017 are numbered
starting from 101.
A list of all parts of IEC 60669 series, under the general title Switches for household and similar
fixed electrical installations, 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 webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn, or
• revised.
SWITCHES FOR HOUSEHOLD AND SIMILAR FIXED
ELECTRICAL INSTALLATIONS –
Part 2-3: Particular requirements –
Time-delay switches (TDS)
1 Scope
IEC 60669-1:2017, Clause 1 is applicable except as follows:
Replacement of the first paragraph with the following:
This part of IEC 60669 applies to time-delay switches (hereinafter referred to as TDS) with a
rated voltage not exceeding 440 V AC and a rated current not exceeding 63 A, intended for
household and similar fixed electrical installations, either indoors or outdoors, operated by hand
and/or by remote control. For the control circuit, the rated control voltage does not exceed
440 V AC or 220 V DC.
TDS are provided with a time-delay device operated by mechanical, thermal, pneumatic,
hydraulic or electrical means or by a combination of them.
Electronic TDS are within the scope of IEC 60669-2-1 but not of this document.
TDS including only passive components such as resistors, capacitors, positive temperature
coefficient (PTC) and negative temperature coefficient (NTC) components and printed circuit
boards are not considered to be electronic TDS.
2 Normative references
IEC 60669-1:2017, Clause 2 is applicable with the following additions:
IEC 60317 (all parts), Specifications for particular types of winding wires
IEC 60445:2021, Basic and safety principles for man-machine interface, marking and
identification – Identification of equipment terminals, conductor terminations and conductors
IEC 60664-1:2020, Insulation coordination for equipment within low-voltage supply systems –
Part 1: Principles, requirements and tests
IEC 60664-3:2016, Insulation coordination for equipment within low-voltage systems – Part 3:
Use of coating, potting or moulding for protection against pollution
IEC 60669-1:2017, Switches for household and similar fixed electrical installations – Part 1:
General requirements
IEC 61558-2-6:2021, Safety of transformers, reactors, power supply units and combinations
thereof – Part 2-6: Particular requirements and tests for safety isolating transformers and power
supply units incorporating safety isolating transformers for general applications

– 6 – IEC 60669-2-3:2024 © IEC 2024
3 Terms and definitions
IEC 60669-1:2017, Clause 3 is applicable with the following modifications:
3.8
thread-cutting screw
Addition of the following note:
Note 101 to entry: This definition is applicable to the switching circuit only.
3.9
mechanical time-delay device
Addition of the following note:
Note 101 to entry: This definition is applicable to the switching circuit only.
Addition of the following new terminological entries:
3.101
time-delay switch
TDS
switch provided with a time-delay device which operates for a certain time (the delay time)
Note 101 to entry: Time-delay switches may be either manually actuated and/or remotely electrically initiated.
3.101.1
electronic TDS
TDS containing electronic component(s)
3.102
rated control voltage
voltage assigned to the control circuit by the manufacturer
3.103
switching circuit
circuit which contains the parts which allow the rated current to flow through the TDS
3.104
control circuit
circuit which includes electrical parts to control the switching circuit in an electrically controlled
TDS
3.105
control mechanism
all parts which are intended for the operation of the TDS
3.106
incorporated hand-operated device
device which allows the switching circuit to be operated, directly or indirectly
Note 101 to entry: An incorporated hand-operated device is not intended for the normal operation of the TDS.
3.107
delay time
period during which the switching circuit(s) is (are) kept closed
Note 101 to entry: Any time taken for the decreasing of the voltage (e.g. to reduce the light) at the end of the delay
period is included within the delay time.

3.108
delay device
all components which have an influence on the delay time
Note 101 to entry: The delay device is energized by means of an impulse into the control circuit in an electrically
controlled TDS.
Note 102 to entry: The delay time may be adjustable.
3.109
disconnectable TDS
TDS consisting of two parts, the first being used as a base and including the terminals, the
other being removable and including the switching and the control circuits, the two parts being
resiliently connected together using a means which allows joining and/or separating with or
without the use of a tool
4 General requirements
IEC 60669-1:2017, Clause 4 is applicable with the following addition:
Addition of the following after the first paragraph:
The operation of a TDS shall not be impaired when it is mounted at an angle deviating by not
more than 5° from the specified position of use.
5 General remarks on tests
IEC 60669-1:2017, Clause 5 is applicable with the following additions:
Addition to Table 1:
Table 1 – Number of specimens needed for the tests
Number of
additional
Number of
Clauses and subclauses specimens for
specimens
dual current
rating
101 Abnormal operation of the control circuit PQR

Addition of the following subclauses:
5.101 Incorporated hand-operated device
If a TDS is provided with an incorporated hand-operated device, actuating the switching circuit
directly, it shall be tested as specified in 19.101.
5.102 Operated by hand
For a TDS operated by hand, the requirements relating to the control voltage do not apply.
5.103 Control and switching circuits without common point
In the case of a TDS for which the control and the switching circuits have no common point, the
test is made with the circuits supplied with the rated voltages which are specified in this
document.
– 8 – IEC 60669-2-3:2024 © IEC 2024
6 Ratings
IEC 60669-1:2017, Clause 6 is applicable except as follows:
6.1 Rated voltage
Replacement of the first paragraph with the following:
Preferred values of rated voltage are:
– AC: 6 V, 8 V, 9 V, 12 V, 24 V, 42 V, 48 V, 110 V, 130 V, 220 V, 230 V and 240 V;
NOTE These rated voltages are aligned with the rated control voltages specified in 6.101 to simplify the tests on
TDS having a common point between the control and switching circuits.
Addition of the following subclause:
6.101 Rated control voltage
Preferred values of rated control voltage are:
– AC: 6 V, 8 V, 9 V, 12 V, 24 V, 42 V, 48 V, 110 V, 130 V, 220 V, 230 V and 240 V;
– DC: 6V, 9 V, 12 V, 24 V, 48 V, 60 V, 110 V and 220 V.
7 Classification
IEC 60669-1:2017, Clause 7 is applicable except as follows:
7.1 according to the possible connections (see Figure 8 of IEC 60669-1:2017):
Replace the existing nine-dash list with the following:
Pattern number
– single-pole switches . 1
– double-pole switches . 2
– three-pole switches . 3
– three-pole plus switched neutral switches . 03
– two-way switches . 6

7.5 according to the method of actuating a switch:
Addition of the following:
– time-delay switches (TDS):
• manually operated;
• remotely operated;
• manually and remotely operated.
NOTE The above methods of operation can be combined with a complementary method of operation allowing
permanent ON and/or permanent OFF. These possibilities are given by a complementary device acting either directly
on the switching circuit, or on the control circuit.

7.7 according to the method of installation, as a consequence of the design of the switch
Addition of the following:
– disconnectable TDS;
Addition of the following subclause:
7.101 according to the type of control mechanism:
– mechanical;
– thermal;
– pneumatic;
– hydraulic;
– electrical;
– combination(s) of the above.
8 Marking
IEC 60669-1:2017, Clause 8 is applicable with the following additions:
8.1 General
Replacement of list item b) with the following:
b) rated voltage(s) in volts and rated control voltage(s) in volts, if different from the rated
voltage(s);
Addition of the following after list item m):
Switches shall be also marked with
n) symbol for the adjustment of the delay time, if applicable;
o) symbols for the positions "Permanent ON" and "Permanent OFF", if applicable;
p) symbol for "Delay time".
Addition after Note 5:
NOTE 101 If a delay time value is indicated, it can be expressed in seconds, minutes and hours.
8.2 Addition of the following symbols:

Permanent ON
If the TDS may also be remote controlled, the symbol |

is not to be used.
Delay time
Permanent OFF but only if the air gap of the switching
contact of the TDS is not less than 3 mm

– 10 – IEC 60669-2-3:2024 © IEC 2024
Adjustment of delay time
Control mechanism
IEC 60417-6457:2023-08
Switch
NOTE 101 In the following country, the symbol consisting of 2 concentric circles is not used to indicate time delay:
UK.
8.3 Visibility of markings
Replace the second paragraph with the following:
Markings as given in 8.1 a), b), c), d), e) and, if applicable, f), g), h), k), l), n), o) and p) shall
be placed on the main part of the TDS.
8.4 Marking on terminals for phase conductors
Addition of the following after the fourth paragraph and before the notes of this Subclause 8.4:
If necessary, the wiring diagram on which the terminal reference is clearly indicated shall be
fixed to the accessory or put inside the protective cover for the terminals.
The terminals of the control circuit shall be marked according to either IEC 60445 or with the
symbols according to 8.2, or both.
9 Checking of dimensions
IEC 60669-1:2017, Clause 9 is applicable.
10 Protection against electric shock
IEC 60669-1:2017, Clause 10 is applicable.
11 Provision for earthing
IEC 60669-1:2017, Clause 11 is applicable.
12 Terminals
IEC 60669-1:2017, Clause 12 is applicable.

13 Constructional requirements
IEC 60669-1:2017, Clause 13 is applicable with the following modifications:
Addition of the following subclauses:
13.101 Reset function
All TDS shall be resettable; this means TDS revert to the full-time delay when the operating
means is actuated during a previously started time delay.
13.102 Transformers intended for SELV circuits
Transformers intended for SELV circuits shall be of the safety isolating type and shall comply
with the relevant requirements of IEC 61558-2-6.
NOTE 101 For the use of SELV, see IEC 61140 and IEC 60364-4-41.
14 Mechanism
IEC 60669-1:2017, Clause 14 is applicable with the following modifications:
Addition of the following subclause:
14.101 Hand-operated device with position indicator
If a TDS is equipped with an incorporated hand-operated device, and if a position indicator is
used, it shall indicate the position of the switching circuit clearly and without ambiguity.
15 Resistance to ageing, protection provided by enclosures of switches and
resistance to humidity
IEC 60669-1:2017, Clause 15 is applicable.
16 Insulation resistance and electric strength
IEC 60669-1:2017, Clause 16 is applicable with the following modifications:
16.3 Electric strength test
Addition to Table 15:
– 12 – IEC 60669-2-3:2024 © IEC 2024
Table 15 – Test voltage, points of application and minimum values of insulating
resistance for the verification of electric strength
Insulation to be tested Minimum Test voltage
value of
insulation
resistance
MΩ V
Switches having Switches having
a rated voltage a rated voltage
not exceeding exceeding
130 V 130 V
101 Between switching circuit(s) and control
circuit(s) if they are separated 5 2 000 3 000
Between SELV/PELV circuits and other circuit(s)
having a higher voltage than SELV/PELV 7 3 000 3 750
103 Between two SELV/PELV circuits 5 500 500

17 Temperature rise
IEC 60669-1:2017, Clause 17 is applicable with the following modifications:
17.1 General
Addition of the following after the fifth paragraph:
TDS are adjusted to the longest delay time indicated by the manufacturer. During the test
the TDS is reclosed at the end of each delay time, within a time of (2 ± 0,5) s.
Electrically operated TDS are operated by means of the control circuit.
18 Making and breaking capacity
IEC 60669-1:2017, Clause 18 is applicable except as follows:
18.2 Overload
Replacement of the first four paragraphs including the dashed list with the following:
TDS are tested at 1,1 times rated voltage and 1,1 times rated control voltage and 1,25 times
+5
rated current. The tolerance for the test voltage and test current is %.
TDS are subjected to 200 operations specified as follows:
– if adjustable, they are adjusted to the shortest delay time, but not shorter than 50 s. The
time interval between switching OFF and ON is adjusted as specified in Clause 17;
– if the maximum adjustable time delay is less than 50 s, the TDS are adjusted to the longest
possible delay time;
– if not adjustable they are tested as delivered.

18.3 Overload test with filament lamps
Addition of the following after the first paragraph:
The operation of the TDS is as specified in 18.2.
19 Normal operation
IEC 60669-1:2017, Clause 19 is applicable except as follows:
19.1 Test for switches intended for inductive loads
Replacement of the first six paragraphs with the following:
TDS shall withstand, without excessive wear or other harmful effect, the mechanical, electrical
and thermal stresses occurring in normal use.
Compliance is checked by the following test.
TDS are tested at rated voltage, rated control voltage and rated current with the connections
specified in 18.2.
The circuit details and the manner of operation of the selector switch S are as described in 18.2,
unless otherwise specified.
For adjustable TDS, the delay time is adjusted to approximately midway and the time interval
between switching OFF and ON is adjusted as specified in Clause 17.
The number of operations is indicated in Table 18; however, for TDS having a long time delay,
the delay time may be reduced to perform the test. In any case, the maximum test duration
is 1 000 h for adjustable and non-adjustable TDS.
For TDS equipped with an incorporated hand-operated device, acting directly on the switching
circuit, 10 % of the operations indicated in Table 18 are made by hand or in an equivalent
manner and for those for AC only the test is followed by that of 14.3.
During the normal operation test, failures of correct operation are allowed to occur within 1 %,
but, no more than three consecutive failures.
Addition of the following subclauses:
19.101 TDS control voltage test
TDS shall operate as intended between 0,9 times and 1,1 times the rated control voltages.
Compliance is checked by the following test.
Under no-load conditions, 20 operations are carried out on each of the three specimens, under
a control voltage of 0,9 times the rated value and 20 operations under a control voltage of 1,1
times the rated value.
TDS shall operate as intended during the test; however, differences in delay times are permitted
according to 19.102.
– 14 – IEC 60669-2-3:2024 © IEC 2024
19.102 TDS delay time accuracy
TDS shall have an adequate repetitive accuracy of delay time.
Compliance is checked by applying the rated control voltage ten times and measuring the delay
time after each application, the TDS not being loaded.
For adjustable TDS the delay time is set to 2,5 min approximately if possible, otherwise, the
test is made with the delay time specified by the manufacturer.
The maximum and minimum values of delay time shall not deviate by more than 15 % from the
mean value of the test.
19.103 TDS delay after revert operation
A TDS shall revert to the full delay time when the operating means is actuated during the delay
time period.
Compliance is checked by the following test.
For a TDS, where the delay time is adjustable, the delay time is adjusted to a time between
2 min and 3 min.
Three specimens are initiated at the rated control voltage.
After 1 min the specimens are again initiated at the rated control voltage.
The total delay time resulting for each of these specimens shall be between 3 min and 4 min.
For a TDS, where the delay time is not adjustable, the specimens are initiated twice at the rated
control voltage, the time difference between the first and the second initiation being 1 min. The
total delay time shall be the delay time (declared by the manufacturer) ±5 % of the delay time
plus 1 min.
For a TDS, where the delay time is not adjustable when the delay time of the TDS is less than
1 min, the second initiation of the TDS shall be after half the delay time declared by the
manufacturer has passed. The total delay time shall be 1,5 times the delay time ±5 %.
20 Mechanical strength
IEC 60669-1:2017, Clause 20 is applicable.
21 Resistance to heat
IEC 60669-1:2017, Clause 21 is applicable with the following addition:
21.1 General
Addition of the following sentence at the end of 21.1 after list item b):
The requirements of 21.1 are applicable to both switching circuits and control circuits.
22 Screws, current-carrying parts and connections
IEC 60669-1:2017, Clause 22 is applicable.

23 Creepage distances, clearances and distances through sealing compound
IEC 60669-1:2017, Clause 23 is applicable with the following modifications:
23.1 General
Addition of the following items to Table 23:
Table 23 – Creepage distances, clearances and distances
through insulating sealing compound
mm
Description
normal mini- micro-
gap gap gap
Creepage distances
101 For creepage distances across which nominal voltages up to 50 V AC or 50 V DC
f g
occur , and which voltages are generated in a circuit by supply from a safety

isolating transformer according to IEC 61558-2-6 or by a supply separated from
the mains supply in an equally effective manner:

– on printed wiring material – pollution degree 1
0,025 0,025 0,025
– on printed wiring material – pollution degree 2
0,04 0,04 0,04
– on other insulating material – across insulating material Group I
0,6 0,6 0,6
– on other insulating material – across insulating material Group II
0,85 0,85 0,85
– on other insulating material – across insulating material Group III
1,2 1,2 1,2
102 For clearance distances across which nominal voltages up to 50 V AC or DC
f
occur , and which voltages are generated in a circuit by supply from a safety

isolating transformer according to IEC 61558-2-6 or by a supply electrically
separated from the mains supply in an equally effective manner:

– pollution degree 1
0,1 0,1 0,1
– pollution degree 2
0,2 0,2 0,2
NOTE 101 The values for the clearances are based on IEC 60664-1:2020, Table F.2, using as input:
– the rated impulse voltage of 800 V derived from IEC 60664-1:2020, Table F.1, for a line-to-neutral voltage of
50 V AC or 50 V DC and overvoltage category III and Case A (inhomogeneous field);
– pollution degrees 1 and 2.
The values for creepage distances are based on IEC 60664-1:2020, Table F.5 with the input of voltage rationalized
for Table F.5 of 50 V RMS from IEC 60664-1:2020, Table F.4, for a supply system having a nominal voltage of 50 V.
NOTE 102 For the definition of nominal voltage, see IEV 601-01-21.

– 16 – IEC 60669-2-3:2024 © IEC 2024
f
For the purposes of this document, the following applies (taken from IEC 60664-1):
Micro-environment: the immediate environment of the insulation which particularly influences the dimensioning
of creepage distances. Ambient conditions which immediately influence the dimensioning of the clearance and
creepage distances (IEC 60664-1:2020, 3.1.23).
Pollution degree: a numeral characterizing the expected pollution of the micro-environment (IEC 60664-1:2020,
3.1.25).
Pollution degree 1: No pollution or only dry, non-conductive pollution occurs. The pollution has no influence.
On printed wiring boards of TDS, it is acceptable to use pollution degree 1, if the printed wiring board is protected
against any occurrence of condensation and deposition of conductive, hydroscopic, or soluble dust. This can
usually be achieved only if the printed wiring board and/or circuits are coated and the coating complies with the
specifications of IEC 60664-3 and an additional encapsulation, or by sealing of the whole printed wiring board
assembly with a protective coating.
Pollution degree 2: Only non-conductive pollution occurs except that occasionally a temporary conductivity
caused by condensation is to be expected. This condensation may occur during periods of ON-OFF load cycles
of the equipment (see IEC 60664-1:2020, 4.5.2).
On printed wiring boards of TDS, it is acceptable to use pollution degree 2, if the printed wiring board and/or
circuit is coated and the coating complies with the specifications of IEC 60664-3.
This document classifies insulating materials according to their PTI values into four groups:
Material Group I 600 ≤ PTI
Material Group II 400 ≤ PTI < 600
Material Group IIIa 175 ≤ PTI < 400
Material Group IIIb 100 ≤ PTI < 175
Material Group III includes Material Group IIIa and Material Group IIIb
A material shall be included in one of the four groups above on the basis that its PTI, established by the method
of IEC 60112 using solution A is equal to or greater than the lower value specified for the group.
g
Values of creepage distances for printed wiring boards are given for pollution degrees 1 and 2. For other
insulating materials, only the values for creepage distances for pollution degree 2 are allowed.

Addition of the following new subclauses:
23.101 Control circuits for connections to a SELV
For TDS having a control circuit suitable for connection to a SELV supply, the switching circuit
being supplied with a voltage greater than the SELV, creepage distances and clearances
between the control and switching circuits shall be not less than 6 mm.
23.102 Use of enamel wires
If the enamel of the wire is at least grade 1 according to IEC 60317 (all parts), the clearances
between the wire of the control coil, the live parts of different polarity and exposed conductive
parts may be reduced to a value equal to two-thirds of the clearances required in the absence
of enamel.
24 Resistance of insulating material to abnormal heat, to fire and to tracking
IEC 60669-1:2017, Clause 24 is applicable with the following modification:
Add the following sentence at the beginning of 24.1 and at the beginning of 24.2:
The requirements of this subclause are applicable to both switching circuits and control circuits.
25 Resistance to rusting
IEC 60669-1:2017, Clause 25 is applicable.

26 EMC requirements
IEC 60669-1:2017, Clause 26 is applicable.
Addition of the following clause:
101 Abnormal operation of the control circuit
TDS shall be so constructed that their behaviour during abnormal operation of the control circuit
(e.g. when the push-button is jammed) is not dangerous to their surroundings or to the user.
Compliance is checked by the following test which is made on three additional specimens of
TDS which have complied with the requirements of Clause 15 and Clause 16.
TDS are mounted, as in normal use, on a matt black painted pine plywood support having a
thickness of approximately 20 mm.
The control circuit is continuously energized at its rated voltage, the switching circuit being
loaded with rated current (at rated voltage) for 6 h. Adjustable TDS are adjusted to the shortest
delay time.
Immediately after this test, the TDS shall still operate and meet the following conditions:
– the temperature rise of any part of the TDS enclosure and plywood support, which may be
touched by the standard test finger, test probe B of IEC 61032, shall not exceed 75 K;
– the temperature rise of the plywood support which cannot be touched by the test finger, test
probe B of IEC 61032, shall not exceed 100 K;
– the TDS shall not emit flames, melted material, glowing particles or burning drops of
insulating material.
After cooling down to ambient temperature:
– the TDS shall withstand a dielectric test between switching and control circuits as specified
in Clause 16, the test voltage being reduced to 75 % of the values specified in Table 15 of
IEC 60669-1:2017;
– the TDS shall still meet the requirements of 10.1.

– 18 – IEC 60669-2-3:2024 © IEC 2024
Annexes
Annexes of IEC 60669-1:2017 apply except as follows:

Annex B
(informative)
Changes planned for the future in order to align IEC 60669-1 with the
requirements of IEC 60998 (all parts), IEC 60999 (all parts) and IEC 60228
IEC 60669-1:2017, Annex B does not apply.

– 20 – IEC 60669-2-3:2024 © IEC 2024
Annex E
(informative)
Additional requirements and tests for switches intended
to be used at a temperature lower than −5 °C
IEC 60669-1:2017, Annex E applies with the following modifications.
Replace 19.4 with the following text:
19.4 Test for TDS intended to be used in ambient temperature below −5 °C
The following additional test shall be carried out on TDS intended to be used below the normal
temperature ranges if marking for low temperature is used:
– wire the TDS with a signal circuit including an indicator to easily evaluate that the TDS is
working as intended during the test;
– the TDS are then kept for 24 h at a temperature of (−25 ± 2) °C;
– the tests of 19.101, 19.102 and 19.103 as applicable are then performed at (−25 ± 2) °C.
For 19.101, 20 operations are performed at rated voltage;
– after these tests the TDS shall show no visible harmful deformation, cracks or similar
damage which would lead to non-compliance with this document;
– verification of operation is checked by the test described in 19.4, immediately followed by
the measurement of the insulation resistance of 16.2 and the electric strength test specified
in 16.3.
IEC 60669-2-3:
...