IEC 60335-2-66:2025

IEC 60335-2-66 ®
Edition 3.0 2025-02
EXTENDED VERSION
INTERNATIONAL
STANDARD
This full version of IEC 60335-2-66:2025 includes the content of the references made to
IEC 60335-1:2020
Household and similar electrical appliances – Safety –
Part 2-66: Particular requirements for water-bed heaters
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IEC 60335-2-66 ®
Edition 3.0 2025-02
EXTENDED VERSION
INTERNATIONAL
STANDARD
This full version of IEC 60335-2-66:2025 includes the content of the references made to
IEC 60335-1:2020
Household and similar electrical appliances – Safety –
Part 2-66: Particular requirements for water-bed heaters
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 97.100.10 ISBN 978-2-8327-0282-6

IEC 60335-1:2020/ISH1:2021 – 1 –
© IEC 2021
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
IEC 60335-1
Edition 6.0  2020-09
HOUSEHOLD AND SIMILAR ELECTRICAL APPLIANCES – SAFETY –

Part 1: General requirements
INTERPRETATION SHEET 1
This interpretation sheet has been prepared by IEC technical committee 61: Safety of
household and similar electrical appliances.
The text of this Interpretation Sheet is based on the following documents:
Draft Report on voting
61/5999/DISH 61/6009/RVDISH
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
___________
INTRODUCTION
Edition 6 of IEC 60335-1:2020 defines and introduces requirements for a detachable
power supply part of an appliance. In the document, 24.2 prohibits the use of a power
supply in a flexible cord.
QUESTION:
Does Subclause 24.2 prohibit the use of a detachable power supply part?
ANSWER
No, a "detachable power supply part" is a defined term and is not captured by the term
"power supply" as used in Subclause 24.2.
NOTE A detachable power supply part is captured by the defined term when the output of the power supply
part is detachable from the class III construction part of the appliance at:
– the power supply part, or
– the class III construction part of the appliance.
However, the supply cord (if any) does not have to be detachable from the detachable power supply part.
ICS 13.120; 97.030
IEC 60335-1:2020-09/ISH1:2021-11(en)

– 2 – IEC 60335-2-66:2025 EXV © IEC 2025
CONTENTS
FOREWORD . 6
INTRODUCTION to IEC 60335-1:2020 . 9
INTRODUCTION to IEC 60335-2-66:2025 . 11
1 Scope . 12
2 Normative references . 12
3 Terms and definitions . 17
4 General requirement . 29
5 General conditions for the tests . 29
6 Classification . 33
7 Marking and instructions . 34
8 Protection against access to live parts . 43
9 Starting of motor-operated appliances . 45
10 Power input and current . 45
11 Heating . 47
12 Charging of metal-ion batteries . 52
13 Leakage current and electric strength at operating temperature . 54
14 Transient overvoltages . 56
15 Moisture resistance . 57
16 Leakage current and electric strength . 60
17 Overload protection of transformers and associated circuits . 62
18 Endurance . 62
19 Abnormal operation . 62
20 Stability and mechanical hazards . 73
21 Mechanical strength . 74
22 Construction . 76
23 Internal wiring . 88
24 Components . 90
25 Supply connection and external flexible cords . 95
26 Terminals for external conductors . 103
27 Provision for earthing . 106
28 Screws and connections . 108
29 Clearances, creepage distances and solid insulation . 110
30 Resistance to heat and fire . 118
31 Resistance to rusting . 122
32 Radiation, toxicity and similar hazards . 122
Annex A (informative) Routine tests . 137
Annex B (normative) Battery-operated appliances, separable batteries and detachable
batteries for battery-operated appliances . 139
Annex C (normative) Ageing test on motors . 160
Annex D (normative) Thermal motor protectors . 161
Annex E (normative) Needle-flame test . 162
Annex F (normative) Capacitors . 163

Annex G (normative) Safety isolating transformers . 165
Annex I (normative) Motors having basic insulation that is inadequate for the rated
voltage of the appliance . 168
Annex J (normative) Coated printed circuit boards . 170
Annex K (informative) Overvoltage categories . 171
Annex L (informative) Guidance for the measurement of clearances and creepage
distances . 172
Annex M (informative) Pollution degree . 175
Annex N (normative) Proof tracking test . 176
Annex O (informative) Selection and sequence of the tests of Clause 30 . 177
Annex P (informative) Guidance for the application of this standard to appliances
used in tropical climates . 182
Annex Q (informative) Sequence of tests for the evaluation of electronic circuits . 184
Annex R (normative) Software evaluation . 187
Annex S (informative) Guidance for the application of this standard on measurement
of power input and current based on the requirements of 10.1 and 10.2 concerning the
representative period . 201
Annex T (normative) UV-C radiation effect on non-metallic materials . 202
Annex U (normative) Appliances intended for remote communication through public
networks . 205
Bibliography . 209
Index of defined terms . 211

Figure 1 – Circuit diagram for leakage current measurement at operating temperature
for single-phase connection of class II appliances and for parts of class ll construction . 123
Figure 2 – Circuit diagram for leakage current measurement at operating temperature
for single-phase connection of other than class II appliances or parts of class ll
construction . 124
Figure 3 – Circuit diagram for leakage current measurement at operating temperature
for three-phase with neutral class II appliances and for parts of class ll construction . 125
Figure 4 – Circuit diagram for leakage current measurement at operating temperature
for three-phase with neutral appliances other than those of class II or parts of class ll
construction . 126
Figure 5 – Small part . 127
Figure 6 – Example of an electronic circuit with low-power points . 127
Figure 7 – Test finger nail . 128
Figure 8 – Flexing test apparatus . 129
Figure 9 – Constructions of cord anchorages . 130
Figure 10 – An example of parts of an earthing terminal . 131
Figure 11 – Examples of clearances . 132
Figure 12 – Example of the placement of the cylinder . 133
Figure 13 – Small parts cylinder . 134
Figure 14 – Example of a specified operating region of a lithium-ion cell during
charging . 135
Figure 101 – Wood block . 136
Figure B.1 – Examples of battery-operated appliance constructions and application of
normative Annex B (1 of 2) . 157

– 4 – IEC 60335-2-66:2025 EXV © IEC 2025
Figure B.2 – Examples of correct polarity connection marking representing three
batteries . 159
Figure I.1 – Simulation of faults . 169
Figure L.1 – Sequence for the determination of clearances . 172
Figure L.2 – Sequence for the determination of creepage distances . 173
Figure L.3 – Measurement of clearances . 174
Figure O.1 – Tests for resistance to heat . 177
Figure O.2 – Selection and sequence of tests for resistance to fire in hand-held
appliances . 178
Figure O.3 – Selection and sequence of tests for resistance to fire in attended
appliances . 178
Figure O.4 – Selection and sequence of tests for resistance to fire in unattended
appliances . 179
Figure O.5 – Some applications of the term "within a distance of 3 mm" . 181
Figure Q.1 – Flowchart outlining the sequence of tests for the evaluation of electronic

circuits (1 of 2) . 185
Figure S.1 – Flowchart giving guidance on measurement of power input and current
concerning the representative period . 201

Table 1 – Power input deviation . 45
Table 2 – Current deviation . 46
Table 3 – Maximum normal temperature rises . 49
Table 4 – Voltage for electric strength test . 56
Table 5 – Characteristics of high-voltage sources . 56
Table 6 – Impulse test voltage . 57
Table 7 – Test voltages. 61
Table 8 – Maximum winding temperature . 65
Table 9 – Maximum abnormal temperature rise . 70
Table 10 – Dimensions of cables and conduits . 96
Table 11 – Minimum cross-sectional area of conductors . 98
Table 12 – Pull force and torque . 100
Table 13 – Nominal cross-sectional area of conductors . 105
Table 14 – Torque for testing screws and nuts . 109
Table 15 – Rated impulse voltage . 111
Table 16 – Minimum clearances . 111
Table 17 – Minimum creepage distances for basic insulation . 115
Table 18 – Minimum creepage distances for functional insulation . 116
Table 19 – Minimum thickness for accessible parts of reinforced insulation consisting
of a single layer . 118
Table A.1 – Test voltages . 138
Table B.1 – Artificial source characteristics . 141
Table B.2 – Total area of openings for metal-ion cells . 149
Table B.3 – Volume of air injected at 2 070 kPa . 149
Table C.1 – Test conditions . 160
Table R.1 – General fault/error conditions . 189

Table R.2 – Specific fault/error conditions . 191
Table R.3 – Semi-formal methods . 197
Table R.4 – Software architecture specification . 197
Table R.5 – Module design specification . 198
Table R.6 – Design and coding standards . 199
Table R.7 – Software safety validation . 199
Table T.1 – Minimum property retention limits after UV-C exposure . 203
Table T.2 – Minimum electric strength for internal wiring after UV-C exposure . 204
Table U.1 – Examples of acceptable measures against unauthorised access and
transmission fault/error modes . 207

– 6 – IEC 60335-2-66:2025 EXV © IEC 2025
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
HOUSEHOLD AND SIMILAR ELECTRICAL APPLIANCES –
SAFETY –
Part 2-66: Particular requirements for water-bed heaters

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,
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preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
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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
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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
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6) All users should ensure that they have the latest edition of this publication.
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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) 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.
This extended version (EXV) of the official IEC Standard provides the user with the full
content of the Standard.
made to IEC 60335-1:2020.
The specific content of IEC 60335-2-66:2025 is displayed on a blue background.

IEC 60335-2-66 has been prepared by IEC technical committee 61: Safety of household and
similar electrical appliances. It is an International Standard.
This third edition cancels and replaces the second edition published in 2002, Amendment 1:
2008 and Amendment 2:2011. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) alignment with IEC 60335-1:2020;
b) conversion of some notes to normative text (Clause 1, 19.4, 22.101);
c) clarification of requirements for remote operation (22.40, 22.49, 22.51).
The text of this International Standard is based on the following documents:
Draft Report on voting
61/7249/CDV 61/7356/RVC
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.
A list of all parts of the IEC 60335 series, under the general title: Household and similar
electrical appliances – Safety, can be found on the IEC website.
This part 2 is to be used in conjunction with the latest edition of IEC 60335-1 and its
amendments unless that edition precludes it; in that case, the latest edition that does not
preclude it is used. It was established on the basis of the sixth edition (2020) of that standard.
NOTE 1 When "Part 1" is mentioned in this standard, it refers to IEC 60335-1.
This part 2 supplements or modifies the corresponding clauses in IEC 60335-1, so as to convert
that publication into the IEC standard: Particular requirements for water-bed heaters.
When a particular subclause of Part 1 is not mentioned in this part 2, that subclause applies as
far as is reasonable. When this standard states "addition", "modification" or "replacement", the
relevant text in Part 1 is to be adapted accordingly.
NOTE 2 The following numbering system is used:
– subclauses, tables and figures that are numbered starting from 101 are additional to those in Part 1;
– unless notes are in a new subclause or involve notes in Part 1, they are numbered starting from 101, including
those in a replaced clause or subclause;
– additional annexes are lettered AA, BB, etc.
NOTE 3 The following print types are used:
– requirements: in roman type;
– test specifications: in italic type;
– notes: in small roman type.
Words in bold in the text are defined in Clause 3. When a definition concerns an adjective, the adjective and the
associated noun are also in bold.

– 8 – IEC 60335-2-66:2025 EXV © IEC 2025
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.
NOTE 4 The attention of National Committees is drawn to the fact that equipment manufacturers and testing
organizations can need a transitional period following publication of a new, amended or revised IEC publication in
which to make products in accordance with the new requirements and to equip themselves for conducting new or
revised tests.
INTRODUCTION to IEC 60335-1:2020
It has been assumed in the drafting of this International Standard that the execution of its
provisions is entrusted to appropriately qualified and experienced persons.
Guidance documents concerning the application of the safety requirements for appliances can
be accessed via TC 61 supporting documents on the IEC website –
www.iec.ch/tc61/supportingdocuments
This information is given for the convenience of users of this International Standard and does
not constitute a replacement for the normative text in this standard.
This standard recognizes the internationally accepted level of protection against hazards such
as electrical, mechanical, thermal, fire and radiation of appliances when operated as in normal
use taking into account the manufacturer's instructions. It also covers abnormal situations that
can be expected in practice and takes into account the way in which electromagnetic
phenomena can affect the safe operation of appliances.
This standard takes into account the requirements of IEC 60364 as far as possible so that there
is compatibility with the wiring rules when the appliance is connected to the supply mains.
However, national wiring rules may differ.
If the functions of an appliance are covered by different parts 2 of IEC 60335, the relevant part 2
is applied to each function separately, as far as is reasonable. If applicable, the influence of
one function on the other is taken into account.
Throughout this publication, when "part 2" is mentioned, it refers to the relevant part of
IEC 60335.
When a part 2 standard does not include additional requirements to cover hazards dealt with in
Part 1, Part 1 applies.
NOTE 1 This means that the technical committees responsible for the part 2 standards have determined that it is
not necessary to specify particular requirements for the appliance in question over and above the general
requirements.
This standard is a product family standard dealing with the safety of appliances and takes
precedence over horizontal and generic standards covering the same subject.
NOTE 2 Horizontal publications, basic safety publications and group safety publications covering a hazard are not
applicable since they have been taken into consideration when developing the general and particular requirements
for the IEC 60335 series of standards.
Individual countries may wish to consider the application of this standard, as far as is
reasonable, to appliances not mentioned in a part 2, and to appliances designed on new
principles. In this case, consideration should be given to defining normal operation, specifying
the classification of the appliance according to Clause 6 and specifying whether the appliance
is operated attended or unattended. Consideration should also be given to particular categories
of likely users and to related specific risks such as access to live parts, hot surfaces or

hazardous moving parts.
An appliance that complies with the text of this standard will not necessarily be considered to
comply with the safety principles of this standard if, when examined and tested, it is found to
have other features which impair the level of safety covered by these requirements.

– 10 – IEC 60335-2-66:2025 EXV © IEC 2025
An appliance employing materials or having forms of construction differing from those detailed
in the requirements of this standard may be examined and tested according to the intent of the
requirements and, if found to be substantially equivalent, may be considered to comply with this
standard.
NOTE 3 Standards dealing with non-safety aspects of household appliances are:
– IEC standards published by TC 59 concerning methods of measuring performance;
– CISPR 11, CISPR 14-1 and relevant IEC 61000-3 series standards concerning electromagnetic emissions;
– CISPR 14-2 concerning electromagnetic immunity;
– IEC standards published by TC 111 concerning environmental matters.

INTRODUCTION to IEC 60335-2-66:2025
It has been assumed in the drafting of this International Standard that the execution of its
provisions is entrusted to appropriately qualified and experienced persons.
Guidance documents concerning the application of the safety requirements for appliances can
be accessed via TC 61 supporting documents on the IEC website.
https://www.iec.ch/tc61/supportingdocuments
This information is given for the convenience of users of this International Standard and does
not constitute a replacement for the normative text in this standard.
This standard recognizes the internationally accepted level of protection against hazards such
as electrical, mechanical, thermal, fire and radiation of appliances when operated as in normal
use taking into account the manufacturer's instructions. It also covers abnormal situations that
can be expected in practice and takes into account the way in which electromagnetic
phenomena can affect the safe operation of appliances.
This standard takes into account the requirements of IEC 60364 as far as possible so that there
is compatibility with the wiring rules when the appliance is connected to the supply mains.
However, national wiring rules can differ.
If an appliance within the scope of this standard also incorporates functions that are covered
by another part 2 of IEC 60335, the relevant part 2 is applied to each function separately, as
far as is reasonable. If applicable, the influence of one function on the other is taken into
account.
When a part 2 standard does not include additional requirements to cover hazards dealt with in
Part 1, Part 1 applies.
NOTE 1 This means that the technical committees responsible for the part 2 standards have determined that it is
not necessary to specify particular requirements for the appliance in question over and above the general
requirements.
This standard is a product family standard dealing with the safety of appliances and takes
precedence over horizontal and generic standards covering the same subject.
NOTE 2 Horizontal publications, basic safety publications and group safety publications covering a hazard are not
applicable since they have been taken into consideration when developing the general and particular requirements
for the IEC 60335 series of standards.
An appliance that complies with the text of this standard will not necessarily be considered to
comply with the safety principles of the standard if, when examined and tested, it is found to
have other features that impair the level of safety covered by these requirements.
An appliance employing materials or having forms of construction differing from those detailed
in the requirements of this standard may be examined and tested according to the intent of the
requirements and, if found to be substantially equivalent, may be considered to comply with the
standard.
NOTE 3 Standards dealing with non-safety aspects of household appliances are:
– IEC standards published by TC 59 concerning methods of measuring performance;
– CISPR 11, CISPR 14-1 and relevant IEC 61000-3 series standards concerning electromagnetic emissions;
– CISPR 14-2 concerning electromagnetic immunity;
– IEC standards published by TC 111 concerning environmental matters.

– 12 – IEC 60335-2-66:2025 EXV © IEC 2025
HOUSEHOLD AND SIMILAR ELECTRICAL APPLIANCES –
SAFETY –
Part 2-66: Particular requirements for water-bed heaters

1 Scope
This part of IEC 60335 deals with the safety of electric water-bed heaters and their associated
control units, for household and similar purposes, their rated voltage being not more
than 250 V, including direct current (DC) supplied appliances.
Appliances not intended for normal household use, but that nevertheless can be a source of
danger to the public, such as appliances intended to be used in hotels, are within the scope of
this standard.
As far as is practicable, this standard deals with the common hazards presented by appliances
that are encountered by all persons in and around the home. However, in general, it does not
take into account
– persons (including children) whose
• physical, sensory or mental capabilities; or
• lack of experience and knowledge
prevents them from using the appliance safely without supervision or instruction;
– children playing with the appliance.
Attention is drawn to the fact that
– for appliances intended to be used in vehicles or on board ships or in aircraft, additional
requirements can be necessary;
– in many countries, additional requirements are specified by the national health authorities,
the national authorities responsible for the protection of labour, the national water supply
authorities and similar authorities.
This standard does not apply to appliances
– for medical purposes (IEC 60601 series);
– intended for immersion in water during use.
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 60034-1, Rotating electrical machines – Part 1: Rating and performance
IEC 60061-1, Lamp caps and holders together with gauges for the control of interchangeability
and safety – Part 1: Lamp caps
IEC 60065:2014, Audio, video and similar electronic apparatus – Safety requirements

IEC 60068-2-2, Environmental testing – Part 2-2: Tests – Test B: Dry heat
IEC 60068-2-31, Environmental testing – Part 2-31: Tests – Test Ec: Rough handling shocks,
primarily for equipment-type specimens
IEC 60068-2-75, Environmental testing – Part 2-75: Tests – Test Eh: Hammer tests
IEC 60068-2-78, Environmental testing – Part 2-78: Tests – Test Cab: Damp heat, steady state
IEC TR 60083, Plugs and socket-outlets for domestic and similar general use standardized in
member countries of IEC
IEC 60085:2007, Electrical insulation – Thermal evaluation and designation
IEC 60112:2003, Method for the determination of the proof and the comparative tracking indices
of solid insulating materials
IEC 60112:2003/AMD1:2009
IEC 60127 (all parts), Miniature fuses
IEC 60227 (all parts), Polyvinyl chloride insulated cables of rated voltages up to and including
450/750 V
IEC 60227-5:2011, Polyvinyl chloride insulated cables of rated voltages up to and including
450/750 V – Part 5: Flexible cables (cords)
IEC 60238, Edison screw lampholders
IEC 60245 (all parts), Rubber insulated cables – Rated voltages up to and including 450/750 V
IEC 60252-1:2010, AC motor capacitors – Part 1: General – Performance, testing and rating –
Safety requirements – Guidance for installation and operation
IEC 60252-1:2010/AMD1:2013
IEC 60309-2, Plugs, socket-outlets and couplers for industrial purposes – Part 2: Dimensional
interchangeability requirements for pin and contact-tube accessories
IEC 60320 (all parts), Appliance couplers for household and similar general purposes
IEC 60320-1, Appliance couplers for household and similar general purposes – Part 1: General
requirements
IEC 60320-2-3, Appliance couplers for household and similar general purposes – Part 2-3:
Appliance couplers with a degree of protection higher than IPX0
IEC 60320-3, Appliance couplers for household and similar general purposes – Part 3: Standard
sheets and gauges
IEC 60384-14:2013, Fixed capacitors for use in electronic equipment – Part 14: Sectional
specification – Fixed capacitors for electromagnetic interference suppression and connection
___________
There exists a consolidated edition 4.1:2009 that includes edition 4 and its Amendment 1.
There exists a consolidated edition 2.1:2013 that includes edition 2 and its Amendment 1.

– 14 – IEC 60335-2-66:2025 EXV © IEC 2025
to the supply mains
IEC 60384-14:2013/AMD1:2016
IEC 60417, Graphical symbols for use on equipment
IEC 60445:2017, 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 60598-1:2014, Luminaires – Part 1: General requirements and tests
IEC 60598-1:2014/AMD1:2017
IEC 60603-11, Connectors for frequencies below 3 MHz for use with printed boards – Part 11:
Detail specification for concentric connectors (dimensions for free connectors and fixed
connectors)
IEC 60664-1:2007, Insulation coordination for equipment within low-voltage 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 60664-4:2005, Insulation coordination for equipment within low-voltage systems – Part 4:
Consideration of high-frequency voltage stress
IEC 60691, Thermal-links – Requirements and application guide
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 60695-2-12, Fire hazard testing – Part 2-12: Glowing/hot-wire based test methods – Glow-
wire flammability index (GWFI) test method for materials
IEC 60695-2-13, Fire hazard testing – Part 2-13: Glowing/hot-wire based test methods – Glow-
wire ignition temperature (GWIT) test method for materials
IEC 60695-10-2, Fire hazard testing – Part 10-2: Abnormal heat – Ball pressure test
IEC 60695-11-5:2016, Fire hazard testing – Part 11-5: Test flames – Needle-flame test method
– Apparatus, confirmatory test arrangement and guidance
IEC 60695-11-10, Fire hazard testing – Part 11-10: Test flames – 50 W horizontal and vertical
flame test methods
___________
There exists a consolidated edition 4.1:2016 that includes edition 4 and its Amendment 1.
There exists a consolidated edition 2.2:2013 that includes edition 2 and its Amendment 1 and Amendment 2.
There exists a consolidated edition 8.1:2017 that includes edition 8 and its Amendment 1.

IEC 60730-1:2013, Automatic ele
...

IEC 60335-2-66 ®
Edition 3.0 2025-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Household and similar electrical appliances – Safety –
Part 2-66: Particular requirements for water-bed heaters

Appareils électrodomestiques et analogues – Sécurité –
Partie 2-66: Exigences particulières pour les dispositifs de chauffage pour
matelas à eau
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IEC 60335-2-66 ®
Edition 3.0 2025-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Household and similar electrical appliances – Safety –

Part 2-66: Particular requirements for water-bed heaters

Appareils électrodomestiques et analogues – Sécurité –

Partie 2-66: Exigences particulières pour les dispositifs de chauffage pour

matelas à eau
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 97.100.10  ISBN 978-2-8327-0233-8

– 2 – IEC 60335-2-66:2025 © IEC 2025
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 7
4 General requirement . 7
5 General conditions for the tests . 7
6 Classification . 8
7 Marking and instructions . 8
8 Protection against access to live parts . 9
9 Starting of motor-operated appliances . 9
10 Power input and current . 9
11 Heating . 9
12 Charging of metal-ion batteries . 10
13 Leakage current and electric strength at operating temperature . 10
14 Transient overvoltages . 10
15 Moisture resistance . 10
16 Leakage current and electric strength . 10
17 Overload protection of transformers and associated circuits . 11
18 Endurance . 11
19 Abnormal operation . 11
20 Stability and mechanical hazards . 11
21 Mechanical strength . 11
22 Construction . 12
23 Internal wiring . 12
24 Components . 12
25 Supply connection and external flexible cords . 13
26 Terminals for external conductors . 13
27 Provision for earthing . 13
28 Screws and connections . 14
29 Clearances, creepage distances and solid insulation . 14
30 Resistance to heat and fire . 14
31 Resistance to rusting . 14
32 Radiation, toxicity and similar hazards . 14
Annexes . 16
Bibliography . 17

Figure 101 – Wood block . 15

Table 12 – Pull force and torque . 13

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
HOUSEHOLD AND SIMILAR ELECTRICAL APPLIANCES –
SAFETY –
Part 2-66: Particular requirements for water-bed heaters

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 60335-2-66 has been prepared by IEC technical committee 61: Safety of household and
similar electrical appliances. It is an International Standard.
This third edition cancels and replaces the second edition published in 2002, Amendment 1:
2008 and Amendment 2:2011. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) alignment with IEC 60335-1:2020;
b) conversion of some notes to normative text (Clause 1, 19.4, 22.101);
c) clarification of requirements for remote operation (22.40, 22.49, 22.51).

– 4 – IEC 60335-2-66:2025 © IEC 2025
The text of this International Standard is based on the following documents:
Draft Report on voting
61/7249/CDV 61/7356/RVC
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.
A list of all parts of the IEC 60335 series, under the general title: Household and similar
electrical appliances – Safety, can be found on the IEC website.
This part 2 is to be used in conjunction with the latest edition of IEC 60335-1 and its
amendments unless that edition precludes it; in that case, the latest edition that does not
preclude it is used. It was established on the basis of the sixth edition (2020) of that standard.
NOTE 1 When "Part 1" is mentioned in this standard, it refers to IEC 60335-1.
This part 2 supplements or modifies the corresponding clauses in IEC 60335-1, so as to convert
that publication into the IEC standard: Particular requirements for water-bed heaters.
When a particular subclause of Part 1 is not mentioned in this part 2, that subclause applies as
far as is reasonable. When this standard states "addition", "modification" or "replacement", the
relevant text in Part 1 is to be adapted accordingly.
NOTE 2 The following numbering system is used:
– subclauses, tables and figures that are numbered starting from 101 are additional to those in Part 1;
– unless notes are in a new subclause or involve notes in Part 1, they are numbered starting from 101, including
those in a replaced clause or subclause;
– additional annexes are lettered AA, BB, etc.
NOTE 3 The following print types are used:
– requirements: in roman type;
– test specifications: in italic type;
– notes: in small roman type.
Words in bold in the text are defined in Clause 3. When a definition concerns an adjective, the adjective and the
associated noun are also in bold.
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.
NOTE 4 The attention of National Committees is drawn to the fact that equipment manufacturers and testing
organizations can need a transitional period following publication of a new, amended or revised IEC publication in
which to make products in accordance with the new requirements and to equip themselves for conducting new or
revised tests.
INTRODUCTION
It has been assumed in the drafting of this International Standard that the execution of its
provisions is entrusted to appropriately qualified and experienced persons.
Guidance documents concerning the application of the safety requirements for appliances can
be accessed via TC 61 supporting documents on the IEC website.
https://www.iec.ch/tc61/supportingdocuments
This information is given for the convenience of users of this International Standard and does
not constitute a replacement for the normative text in this standard.
This standard recognizes the internationally accepted level of protection against hazards such
as electrical, mechanical, thermal, fire and radiation of appliances when operated as in normal
use taking into account the manufacturer's instructions. It also covers abnormal situations that
can be expected in practice and takes into account the way in which electromagnetic
phenomena can affect the safe operation of appliances.
This standard takes into account the requirements of IEC 60364 as far as possible so that there
is compatibility with the wiring rules when the appliance is connected to the supply mains.
However, national wiring rules can differ.
If an appliance within the scope of this standard also incorporates functions that are covered
by another part 2 of IEC 60335, the relevant part 2 is applied to each function separately, as
far as is reasonable. If applicable, the influence of one function on the other is taken into
account.
When a part 2 standard does not include additional requirements to cover hazards dealt with in
Part 1, Part 1 applies.
NOTE 1 This means that the technical committees responsible for the part 2 standards have determined that it is
not necessary to specify particular requirements for the appliance in question over and above the general
requirements.
This standard is a product family standard dealing with the safety of appliances and takes
precedence over horizontal and generic standards covering the same subject.
NOTE 2 Horizontal publications, basic safety publications and group safety publications covering a hazard are not
applicable since they have been taken into consideration when developing the general and particular requirements
for the IEC 60335 series of standards.
An appliance that complies with the text of this standard will not necessarily be considered to
comply with the safety principles of the standard if, when examined and tested, it is found to
have other features that impair the level of safety covered by these requirements.
An appliance employing materials or having forms of construction differing from those detailed
in the requirements of this standard may be examined and tested according to the intent of the
requirements and, if found to be substantially equivalent, may be considered to comply with the
standard.
NOTE 3 Standards dealing with non-safety aspects of household appliances are:
– IEC standards published by TC 59 concerning methods of measuring performance;
– CISPR 11, CISPR 14-1 and relevant IEC 61000-3 series standards concerning electromagnetic emissions;
– CISPR 14-2 concerning electromagnetic immunity;
– IEC standards published by TC 111 concerning environmental matters.

– 6 – IEC 60335-2-66:2025 © IEC 2025
HOUSEHOLD AND SIMILAR ELECTRICAL APPLIANCES –
SAFETY –
Part 2-66: Particular requirements for water-bed heaters

1 Scope
This clause of Part 1 is replaced by the following.
This part of IEC 60335 deals with the safety of electric water-bed heaters and their associated
control units, for household and similar purposes, their rated voltage being not more
than 250 V, including direct current (DC) supplied appliances.
Appliances not intended for normal household use, but that nevertheless can be a source of
danger to the public, such as appliances intended to be used in hotels, are within the scope of
this standard.
As far as is practicable, this standard deals with the common hazards presented by appliances
that are encountered by all persons in and around the home. However, in general, it does not
take into account
– persons (including children) whose
• physical, sensory or mental capabilities; or
• lack of experience and knowledge
prevents them from using the appliance safely without supervision or instruction;
– children playing with the appliance.
Attention is drawn to the fact that
– for appliances intended to be used in vehicles or on board ships or in aircraft, additional
requirements can be necessary;
– in many countries, additional requirements are specified by the national health authorities,
the national authorities responsible for the protection of labour, the national water supply
authorities and similar authorities.
This standard does not apply to appliances
– for medical purposes (IEC 60601 series);
– intended for immersion in water during use.
2 Normative references
This clause of Part 1 is applicable except as follows.
Addition:
ISO 2439, Flexible cellular polymeric materials – Determination of hardness (indentation
technique)
3 Terms and definitions
This clause of Part 1 is applicable except as follows.
3.1 Definitions relating to physical characteristics
3.1.9 Modification:
Replace the first paragraph with the following:
operation of the appliance after the heater has been installed under a water mattress, taking
into account the installation instructions
Note 101 to entry: See 5.10 for additional details of the appliance installation for normal operation.
3.5 Definitions relating to types of appliances
3.5.101
water-bed heater
appliance incorporating a heating element within an enclosure and intended for use under a
water mattress
Note 1 to entry: The appliance can be contained in an envelope of the mattress.
Note 2 to entry: The appliance can incorporate a thermostat having a sensing element that is positioned during
installation.
4 General requirement
This clause of Part 1 is applicable.
5 General conditions for the tests
This clause of Part 1 is applicable except as follows.
5.3 Addition:
The test of 21.101 is carried out immediately after the test of Clause 11.
5.10 Addition:
For normal operation, the appliance is supported by a wooden base that is consistent with the
size of the mattress. The top of the base consists of plywood approximately 13 mm thick and is
supported 150 mm above the floor by pinewood boards approximately 20 mm thick. The boards
are assembled to form a rectangular framework that includes a longitudinal and two transverse
members to produce six approximately equal sections.
The wooden base is completely covered by a sheet of open-cell polyether approximately 25 mm
thick. The polyether has the following composition:
+2
– cell count: 18 per cm;
+10 %
– specific mass: 30 kg/m ;
– hardness: 120 N to 170 N at 40 % impression, measured according to ISO 2439.
This polyether sheet is omitted if the instructions state that the heater is unsuitable for use on
a soft support.
– 8 – IEC 60335-2-66:2025 © IEC 2025
Additional material is placed on the polyether sheet if this is stated in the instructions.
The heater, together with any control, is positioned on the polyether sheet. A piece of the bottom
layer of water mattress material, having dimensions 100 mm × 200 mm, is folded to form a
crease 50 mm × 200 mm. It is placed on the upper surface of the heater, parallel to the shortest
side and approximately in the centre of the longest side.
The mattress is placed over the heater, filled with water and completely covered by another
piece of polyether sheet approximately 36 mm thick.
6 Classification
This clause of Part 1 is applicable except as follows.
6.1 Addition:
The rated voltage of class III appliances shall not exceed 24 V.
6.2 Addition:
Parts of the appliance, other than those of class III, that are intended to be placed under the
water mattress shall be at least IPX7.
7 Marking and instructions
This clause of Part 1 is applicable except as follows.
7.1 Addition:
The appliance shall be marked with the substance of the following:
– read the instructions carefully;
– check that the heater, the mattress and any envelope are laid flat and without folds before
filling the mattress with water;
– place the heater centrally under the mattress so that it does not project from the sides of
the mattress enclosure;
– the support under the heater is to be flat, continuous and without sharp edges;
– use only to heat water-beds;
– this side up, if applicable.
The appliance shall be marked with the model or type reference of a detachable control unit,
if applicable, intended for use with the appliance.
7.12 Addition:
The instructions shall include the substance of the following:
– the heater is only to be used with the type of detachable control unit that is marked on the
appliance, if applicable;
– the appliance is not intended for use in hospitals;
– the appliance is intended only to heat water-beds;
– sharp objects such as needles and pins must not be inserted in the appliance;
– bedding is not to come into contact with the heater.

The instructions for appliances other than those with a polarized plug shall describe the
orientation of the plug in the socket-outlet of class II appliances provided with a metal screen
to minimize the capacitive leakage current and the electrostatic field. The means of checking
the orientation shall be specified.
7.12.1 Addition:
The installation instructions shall include the following:
– the details of the installation of the heater and its control. In particular, details shall be given
regarding the correct positioning and installation of any temperature sensing element of the
control unit, to ensure that it does not easily slip out of position;
– the minimum dimensions of the water mattress and the minimum depth of water with which
it is to be filled;
– details of any additional supporting material required if the heater is installed on a soft
support, or a statement that the heater is unsuitable for such installation.
7.101 Detachable control units shall be marked with:
– rated voltage or rated voltage range in volts;
– symbol for nature of supply, unless the rated frequency is marked;
– name, trade mark or identification mark of the manufacturer or responsible vendor;
– model or type reference;
– identification of the relevant water-bed heater.
Compliance is checked by inspection.
8 Protection against access to live parts
This clause of Part 1 is applicable.
9 Starting of motor-operated appliances
This clause of Part 1 is not applicable.
10 Power input and current
This clause of Part 1 is applicable.
11 Heating
This clause of Part 1 is applicable except as follows.
11.2 Replacement:
The appliance is installed as specified for normal operation.
11.3 Addition:
The temperature rise of the surface of the water-bed heater and the surface temperature of
the mattress are determined by means of fine-wire thermocouples attached to oxidized copper
or brass plates measuring 65 mm × 65 mm × 0,5 mm.

– 10 – IEC 60335-2-66:2025 © IEC 2025
11.4 Addition:
Thermostats are short-circuited if their sensing elements are not fixed in relation to the heater
after installation.
NOTE 101 Sensing elements are not considered to be fixed if they are positioned outside the enclosure of the
heater and without provision for fixing.
11.7 Modification:
Replace the first paragraph with the following:
The appliance is operated until steady conditions are established.
11.8 Addition:
The temperature rise of the surface of the water-bed heater shall not exceed 35 K except under
the folded material where the limit is 60 K.
11.101 The appliance shall operate without risk of heat-stroke to the user.
Compliance is checked by the following test.
The appliance is operated as specified in 11.1 to 11.7 except that thermostats are not short-
circuited. Controls are set in the lowest position.
The temperature of the upper surface of the water mattress shall not exceed 37 °C.
12 Charging of metal-ion batteries
This clause of Part 1 is applicable.
13 Leakage current and electric strength at operating temperature
This clause of Part 1 is applicable except as follows.
13.2 Addition:
The leakage current of class II appliances provided with a metal screen connected to live
parts shall not exceed 0,25 mA when the selector switch is in one position and 0,75 mA in the
other position.
14 Transient overvoltages
This clause of Part 1 is applicable.
15 Moisture resistance
This clause of Part 1 is applicable.
16 Leakage current and electric strength
This clause of Part 1 is applicable.

17 Overload protection of transformers and associated circuits
This clause of Part 1 is applicable.
18 Endurance
This clause of Part 1 is not applicable.
19 Abnormal operation
This clause of Part 1 is applicable except as follows.
19.2 Addition:
The test is carried out without the folded water mattress material.
The water mattress is empty.
19.4 Addition:
This test is not carried out when the thermostat is short-circuited during the test of Clause 11.
19.13 Addition:
The temperature rise of the surface of the water-bed heater shall not exceed 100 K.
The tests shall not impair the degree of protection of the appliance against harmful ingress of
water.
19.101 The appliance is operated under the conditions of Clause 11 but without the folded
water mattress material. The water-bed heater is positioned so that it extends outside the
waterbed envelope by 10 cm along its longest side and it is supplied at rated power input.
The temperature rise of the surface of the water-bed heater that extends beyond the mattress
enclosure shall not exceed 65 K but a first overshoot up to 95 K is allowed.
20 Stability and mechanical hazards
This clause of Part 1 is applicable.
21 Mechanical strength
This clause of Part 1 is applicable except as follows.
21.101 Appliances provided with a flexible support for the heater shall withstand the
mechanical stresses that the heater can be subjected to during normal use.
Compliance is checked by the following test.
The appliance is operated as specified in Clause 11 but without the covering sheet of polyether.

– 12 – IEC 60335-2-66:2025 © IEC 2025
The water mattress is subjected to a downward force of 950 N ± 40 N by means of the wood
block shown in Figure 101 that is positioned in the most unfavourable place. The force is applied
25 000 times at a rate of approximately 30 times per minute.
During the test, the power input shall not deviate from the power input measured at the start of
the test by more than +5 % and –10 %.
After the test, the heater shall not be damaged to such an extent that compliance with this
standard is impaired.
22 Construction
This clause of Part 1 is applicable except as follows.
22.40 Addition:
These appliances are not considered to be appliances that could give rise to a hazard when
operated continuously, automatically or remotely.
22.49 Not applicable.
22.51 Not applicable.
22.101 Class II appliances having a metal screen connected to live parts and without a
polarized plug shall incorporate a means to indicate that the plug has been inserted in the
socket outlet so that the leakage current is minimized.
Compliance is checked by inspection and by manual test.
NOTE The indicating means can require a manual action. A light-emitting diode that glows when a surface is
touched is an example of a device that can be used.
22.102 Class I appliances having an earthed metal screen shall incorporate supplementary
insulation between the screen and the accessible surfaces.
Compliance is checked by inspection.
23 Internal wiring
This clause of Part 1 is applicable except as follows.
23.5 Addition:
Natural rubber shall not be used for the insulation of internal wiring.
24 Components
This clause of Part 1 is applicable except as follows.
24.1.4 Modification:
The number of cycles of operation for voltage-maintained non-self-resetting thermal cut-outs
is increased to 10 000.
24.2 Modification:
Delete "switches, automatic controls," from the first dashed item.
Addition:
Appliances may be fitted with switches and control units in flexible cords.
24.101 Thermal cut-outs shall not be self-resetting thermal cut-outs.
Compliance is checked by inspection.
25 Supply connection and external flexible cords
This clause of Part 1 is applicable except as follows.
25.5 Addition:
Type Z attachment is allowed.
25.7 Modification:
Delete "for appliances having a mass not exceeding 3 kg" from the first bullet under the third
and fourth dashed items.
25.15 Modification:
In the fourth paragraph, replace "at a distance of approximately 20 mm from the cord
anchorage" with "at the cord anchorage".
Replace Table 12 with the following:
Table 12 – Pull force and torque
Cord usage Pull force Torque
N Nm
Interconnection cords 100 0,1
Supply cords 60 0,1
25.23 Addition:
The insulation of interconnection cords shall be at least equivalent to that of ordinary polyvinyl
chloride sheathed flexible cord (code designation 60227 IEC 53).
26 Terminals for external conductors
This clause of Part 1 is applicable.
27 Provision for earthing
This clause of Part 1 is applicable.

– 14 – IEC 60335-2-66:2025 © IEC 2025
28 Screws and connections
This clause of Part 1 is applicable.
29 Clearances, creepage distances and solid insulation
This clause of Part 1 is applicable except as follows.
29.3 Addition:
If the insulation is in more than one layer, it shall not be accessible after installation of the
heater.
30 Resistance to heat and fire
This clause of Part 1 is applicable except as follows.
30.1 Addition:
The test is not applied to the enclosure of the heater.
30.2.2 Not applicable.
31 Resistance to rusting
This clause of Part 1 is applicable.
32 Radiation, toxicity and similar hazards
This clause of Part 1 is applicable.

Dimensions in millimetres
+
Key
A point of application of the load
Figure 101 – Wood block
– 16 – IEC 60335-2-66:2025 © IEC 2025
Annexes
The annexes of Part 1 are applicable.

Bibliography
The Bibliography of Part 1 is applicable except as follows.
Addition:
IEC 60601 (all parts), Medical electrical equipment

___________
– 18 – IEC 60335-2-66:2025 © IEC 2025
SOMMAIRE
AVANT-PROPOS . 19
INTRODUCTION . 22
1 Domaine d'application . 24
2 Références normatives . 24
3 Termes et définitions . 25
4 Exigence générale . 25
5 Conditions générales d'essais . 25
6 Classification . 26
7 Marquage et instructions . 26
8 Protection contre l'accès aux parties actives . 27
9 Démarrage des appareils à moteur . 27
10 Puissance et courant . 27
11 Échauffements . 28
12 Charge des batteries à ions métalliques . 28
13 Courant de fuite et rigidité diélectrique à la température de régime . 28
14 Surtensions transitoires . 29
15 Résistance à l'humidité . 29
16 Courant de fuite et rigidité diélectrique . 29
17 Protection contre la surcharge des transformateurs et des circuits associés . 29
18 Endurance . 29
19 Fonctionnement anormal . 29
20 Stabilité et dangers mécaniques . 30
21 Résistance mécanique. 30
22 Construction . 30
23 Conducteurs internes . 31
24 Composants . 31
25 Raccordement au réseau et câbles souples extérieurs . 31
26 Bornes pour conducteurs externes . 32
27 Dispositions en vue de la mise à la terre . 32
28 Vis et connexions . 32
29 Distances dans l'air, lignes de fuite et isolation solide . 32
30 Résistance à la chaleur et au feu . 32
31 Protection contre la rouille . 33
32 Rayonnement, toxicité et dangers analogues . 33
Annexes . 34
Bibliographie . 35

Figure 101 – Bloc en bois . 33

Tableau 12 – Force de traction et couple de torsion . 32

COMMISSION ÉLECTROTECHNIQUE INTERNATIONALE
____________
APPAREILS ÉLECTRODOMESTIQUES ET ANALOGUES –
SÉCURITÉ –
Partie 2-66: Exigences particulières pour
les dispositifs de chauffage pour matelas à eau

AVANT-PROPOS
1) La Commission Électrotechnique Internationale (IEC) est une organisation mondiale de normalisation composée
de l'ensemble des comités électrotechniques nationaux (Comités nationaux de l'IEC). L'IEC a pour objet de
favoriser la coopération internationale pour toutes les questions de normalisation dans les domaines de
l'électricité et de l'électronique. À cet effet, l'IEC – entre autres activités – publie des Normes internationales,
des Spécifications techniques, des Rapports techniques, des Spécifications accessibles au public (PAS) et des
Guides (ci-après dénommés "Publication(s) de l'IEC"). Leur élaboration est confiée à des comités d'études, aux
travaux desquels tout Comité national intéressé par le sujet traité peut participer. Les organisations
internationales, gouvernementales et non gouvernementales, en liaison avec l'IEC, participent également aux
travaux. L'IEC collabore étroitement avec l'Organisation Internationale de Normalisation (ISO), selon des
conditions fixées par accord entre les deux organisations.
2) Les décisions ou accords officiels de l'IEC concernant les questions techniques représentent, dans la mesure du
possible, un accord international sur les sujets étudiés, étant donné que les Comités nationaux de l'IEC intéressés
sont représentés dans chaque comité d'études.
3) Les Publications de l'IEC se présentent sous la forme de recommandations internationales et sont agréées
comme telles par les Comités nationaux de l'IEC. Tous les efforts raisonnables sont entrepris afin que l'IEC
s'assure de l'exactitude du contenu technique de ses pub
...