IEC 60335-2-34:2021

Household and similar electrical appliances - Safety - Part 2-34: Particular requirements for motor-compressors

IEC 60335-2-34:2021 deals with the safety of sealed (hermetic and semi-hermetic type) motor-compressors, their protection and control systems, if any, which are intended for use in equipment for household and similar purposes and which conform with the standards applicable to such equipment. It applies to motor-compressors tested separately, under the most severe conditions that may be expected to occur in normal use, their rated voltage being not more than 250 V for single-phase motor-compressors and 600 V for other motor-compressors.
This standard also covers:
- multi-speed motor-compressors, that are motor-compressors, the speed of which can be set to different values;
- variable capacity motor-compressors that are motor-compressors where the capacity of the compressor is controlled at fixed speeds.
Examples of equipment which contain motor-compressors are:
- tumble dryers (IEC 60335-2-11);
- refrigerating appliances, ice-cream appliances and ice-makers (IEC 60335-2-24);
- electrical heat pumps, air-conditioners and dehumidifiers (IEC 60335-2-40);
- commercial dispensing appliances and vending machines (IEC 60335-2-75);
- commercial refrigerating appliances and ice-makers with an incorporated or remote refrigerant unit or compressor (IEC 60335-2-89);
- electrical equipment for measurement, control, and laboratory use (IEC 61010-2-011);
- professional ice-cream makers (IEC 60335-2-118);
- refrigerating systems and heat pumps – Design, construction, testing, marking and documentation (ISO 5149-2).
This standard does not supersede the requirements of standards relevant to the particular appliance in which the motor-compressor is used. However, if the motor-compressor type used complies with this standard, the tests for the motor-compressor specified in the particular appliance standard may not need to be made in the particular appliance or assembly. If the motor-compressor control system is associated with the particular appliance control system, additional tests could be necessary on the final appliance.
So far as is practical, this standard deals with the common hazards presented by motor-compressors used in appliances which are encountered by all persons in and around the home. However, it does not in general take into account:
- the use of appliances by young children or infirm persons without supervision;
- playing with the appliances by young children.
Attention is drawn to the fact that:
- for motor-compressors intended to be used in appliances in vehicles or on board ships, additional require¬ments could be necessary;
- in many countries, additional requirements are specified by the national health authorities, the national authorities responsible for the protection of labour and similar authorities.
This standard does not apply to:
- motor-compressors designed exclusively for industrial purposes;
- motor-compressors used in appliances intended to be used in locations where special conditions prevail, such as the presence of a corrosive or explosive atmosphere (dust, vapour or gas).
If motor-compressors for refrigerant R-744 used in appliances with a transcritical refrigeration system are equipped with pressure relief devices, compliance with the requirements for these devices is checked during the tests on the final appliance.
This sixth edition cancels and replaces the fifth edition published in 2012, Amendment 1:2015 and Amendment 2:2016. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous edition:
- it aligns the text with IEC 60335-1, Ed 5.2;
- application categories and tests have been extended (3.1.102, Annex AA);
- use of a motorette for winding wire compatibility tests introduced (3.8.102, Annex BB);
- height of the triangle, symbol ISO 7010 W021 has been introduced (7.14);
- some notes are converted to normative text (1, 15.3, 22.21, 23.8, 29.3.4, Figure AA.1);
- note in Subclause 6.101 bec

Appareils électrodomestiques et analogues - Sécurité - Partie 2-34: Exigences particulières pour les motocompresseurs

L'IEC 60335-2-34:2021 traite de la sécurité des motocompresseurs étanches (de type hermétique et hermétique accessible) et, le cas échéant, de leurs systèmes de protection et de commande, qui sont destinés à être utilisés sur les appareils électrodomestiques et analogues et qui sont conformes aux normes applicables à de tels matériels. Elle s'applique aux motocompresseurs soumis à l'essai séparément, dans les conditions les plus défavorables qui peuvent se produire en usage normal, dont la tension assignée est inférieure ou égale à 250 V pour les motocompresseurs monophasés et à 600 V pour les autres motocompresseurs.
La présente norme couvre également:
- les motocompresseurs à plusieurs vitesses, qui sont des motocompresseurs dont la vitesse peut être réglée sur différentes valeurs;
- les motocompresseurs à capacité variable, qui sont des motocompresseurs dont la capacité du compresseur est contrôlée à des vitesses fixes.
Des exemples d'appareils équipés de motocompresseurs sont:
- les sèche-linge (IEC 60335-2-11);
- les appareils de réfrigération, les sorbetières et les fabriques de glace (IEC 60335-2-24);
- les pompes à chaleur électriques, les climatiseurs et les déshumidificateurs (IEC 60335-2-40);
- les distributeurs commerciaux avec ou sans moyen de paiement (IEC 60335-2-75);
- les appareils de réfrigération et fabriques de glace à usage commercial avec une unité de fluide frigorigène ou un motocompresseur incorporés ou à distance (IEC 60335-2-89);
- exigences de sécurité pour les appareils électriques de mesurage, de régulation et de laboratoire – exigences particulières pour les appareils de réfrigération (IEC 61010-2-011);
- les fabriques de crème glacée à usage professionnel (IEC 60335-2-118);
- les systèmes frigorifiques et pompes à chaleur – conception, construction, essais, marquage et documentation (ISO 5149-2).
La présente norme ne remplace pas les exigences des normes applicables aux appareils dans lesquels sont utilisés les motocompresseurs. Toutefois, si le type de motocompresseur utilisé est conforme à la présente norme, il peut ne pas être nécessaire d'effectuer les essais sur l'appareil ou l'ensemble particulier pour les motocompresseurs spécifiés dans les normes applicables à ces appareils. Si le dispositif de commande du motocompresseur est associé au dispositif de commande d'un appareil particulier, il peut être nécessaire d'effectuer des essais supplémentaires sur l'appareil final.
Dans la mesure du possible, la présente norme traite des dangers courants que présentent les motocompresseurs utilisés dans des appareils et auxquels sont exposés tous les individus situés à l'intérieur et autour de l'habitation. Cependant, cette norme ne tient pas compte en général:
- de l'utilisation des appareils par de jeunes enfants ou des personnes handicapées sans surveillance;
- de l'utilisation des appareils comme jouet par de jeunes enfants.
L'attention est attirée sur le fait que:
- pour les motocompresseurs destinés à être utilisés dans des véhicules ou à bord de navires, des exigences supplémentaires peuvent être nécessaires;
- dans de nombreux pays, des exigences supplémentaires sont spécifiées par les organismes nationaux de la santé, par les organismes nationaux responsables de la protection des travailleurs et par des organismes similaires.
La présente norme ne s'applique pas:
- aux motocompresseurs prévus exclusivement pour des usages industriels;
- aux motocompresseurs utilisés dans des appareils destinés à être employés dans des locaux qui présentent des conditions particulières, telles que la présence d'une atmosphère corrosive ou explosive (poussière, vapeur ou gaz).
Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
- le texte a été aligné sur l'IEC 60335-1, Ed 5.2;
- les catégories d'applications et les essais ont été élargis (3.1.102, Annexe AA);
- l'emploi d'une motorette a été ajouté pour les essais de compatibilité de

General Information

• Status: Published
• Publication Date: 10-Mar-2021
• ICS: 97.040.30 - Domestic refrigerating appliances
• Technical Committee: SC 61C - Safety of refrigeration appliances for household and commercial use
• Drafting Committee: MT 1 - TC 61/SC 61C/MT 1
• Current Stage: DELPUB - Deleted Publication
• Start Date: 20-Nov-2024
• Completion Date: 16-Dec-2022

Relations

• Revises: IEC 60335-2-34:2012/AMD1:2015/COR1:2015 - Corrigendum 1 - Amendment 1 - Household and similar electrical appliances - Safety - Part 2-34: Particular requirements for motor-compressors
• Effective Date: 05-Sep-2023
• Revised: IEC 60335-2-34:2024 - Household and similar electrical appliances - Safety - Part 2-34: Particular requirements for motor-compressors
• Effective Date: 05-Sep-2023
• Revises: IEC 60335-2-34:2012 - Household and similar electrical appliances - Safety - Part 2-34: Particular requirements for motor-compressors
• Effective Date: 05-Sep-2023
• Revises: IEC 60335-2-34:2012/AMD1:2015 - Amendment 1 - Household and similar electrical appliances - Safety - Part 2-34: Particular requirements for motor-compressors
• Effective Date: 05-Sep-2023
• Revises: IEC 60335-2-34:2012/AMD2:2016 - Amendment 2 - Household and similar electrical appliances - Safety - Part 2-34: Particular requirements for motor-compressors
• Effective Date: 05-Sep-2023
• Revises: IEC 60335-2-34:2012/AMD2:2016/COR1:2017 - Corrigendum 1 - Amendment 2 - Household and similar electrical appliances - Safety - Part 2-34: Particular requirements for motor-compressors
• Effective Date: 05-Sep-2023

Overview

IEC 60335-2-34:2021 is the International Electrotechnical Commission (IEC) safety standard that specifies particular requirements for sealed motor‑compressors (hermetic and semi‑hermetic types) intended for use in household and similar electrical appliances. It covers motor‑compressors tested separately under the most severe conditions expected in normal use, with rated voltages up to 250 V for single‑phase units and 600 V for other motor‑compressors. The 2021 edition (Edition 6.0) is a technical revision that aligns the text with IEC 60335‑1 and introduces extended application categories and new test methods.

Key topics and technical requirements

• Scope and applicability: Includes multi‑speed and variable‑capacity motor‑compressors intended for household and similar appliances; excludes units designed exclusively for industrial use or for special atmospheres (corrosive/explosive).
• Safety testing: Requires separate testing under severe operating conditions (locked‑rotor, overload, endurance, moisture resistance, leakage current, electric strength, transient overvoltages).
• Mechanical and thermal requirements: Covers mechanical strength, stability, heating, insulation resistance and compatibility, and protection against access to live parts.
• Control and protection: Addresses motor‑compressor control systems and how integrated controls may affect final appliance testing.
• Special tests and annexes:
  • Annex AA: Extended running overload tests and application categories.
  • Annex BB: Winding wire insulation compatibility tests using a motorette.
  • Annex CC / EE: Tie cord/insulation compatibility and optional pressure endurance/fatigue tests.
• Additional considerations: Requirements for pressure relief devices for R‑744 (CO2) transcritical systems; altitude clearances (>2 000 m) clarified.
• Marking & instructions: Specified labeling and documentation requirements (including safety symbols like ISO 7010 W021).

Practical applications and who uses this standard

IEC 60335‑2‑34 is used by:

• Appliance manufacturers (refrigeration, heat pumps, dehumidifiers, ice‑makers, vending machines) to specify safe motor‑compressors and reduce duplicate testing in final products.
• Motor‑compressor designers and component suppliers to validate design, insulation compatibility, and endurance.
• Test laboratories and conformity assessment bodies for type testing and certification against household safety requirements.
• Regulators and safety engineers to reference accepted international safety criteria.

Examples of appliances that contain motor‑compressors: tumble dryers, refrigerating appliances, air‑conditioners, heat pumps, vending machines and professional ice‑cream makers.

Related standards

• IEC 60335‑1 (general household appliance safety)
• IEC 60335‑2‑11, ‑2‑24, ‑2‑40, ‑2‑75, ‑2‑89, ‑2‑118 (particular appliance standards)
• IEC 61010‑2‑011 (measurement/control equipment)
• ISO 5149‑2 (refrigerating systems and heat pumps design/testing)

Keywords: IEC 60335‑2‑34:2021, motor‑compressor safety, hermetic motor‑compressors, motor‑compressor testing, motorette, Annex AA, insulation compatibility, household appliance standards.

Standards Content (Sample)

IEC 60335-2-34 ®
Edition 6.0 2021-03
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Household and similar electrical appliances – Safety –
Part 2-34: Particular requirements for motor-compressors

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local IEC member National Committee for further information.

IEC Central Office Tel.: [phone]
3, rue de Varembé [e-mail]
CH-1211 Geneva 20 www.iec.ch
Switzerland
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

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

IEC publications search - webstore.iec.ch/advsearchform IEC online collection - oc.iec.ch
The advanced search enables to find IEC publications by a Discover our powerful search engine and read freely all the
variety of criteria (reference number, text, technical publications previews. With a subscription you will always
committee, …). It also gives information on projects, replaced have access to up to date content tailored to your needs.
and withdrawn publications.
Electropedia - www.electropedia.org
IEC Just Published - webstore.iec.ch/justpublished
The world's leading online dictionary on electrotechnology,
Stay up to date on all new IEC publications. Just Published
containing more than 22 000 terminological entries in English
details all new publications released. Available online and
and French, with equivalent terms in 18 additional languages.
once a month by email.
Also known as the International Electrotechnical Vocabulary

(IEV) online.
IEC Customer Service Centre - webstore.iec.ch/csc

If you wish to give us your feedback on this publication or
need further assistance, please contact the Customer Service
Centre: [e-mail].
IEC 60335-2-34 ®
Edition 6.0 2021-03
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Household and similar electrical appliances – Safety –

Part 2-34: Particular requirements for motor-compressors

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 97.040.30 ISBN 978-2-8322-9573-1

– 2 – IEC 60335-2-34:2021 RLV © IEC 2021
CONTENTS
FOREWORD . 4
INTRODUCTION . 2
1 Scope . 9
2 Normative references . 10
3 Terms and definitions . 10
4 General requirement . 10
5 General conditions for the tests . 14
6 Classification . 15
7 Marking and instructions . 16
8 Protection against access to live parts . 17
9 Starting of motor-operated appliances . 17
10 Power input and current . 17
11 Heating . 17
12 Void . 17
13 Leakage current and electric strength at operating temperature . 17
14 Transient overvoltages . 18
15 Moisture resistance . 18
16 Leakage current and electric strength . 18
17 Overload protection of transformers and associated circuits . 18
18 Endurance . 18
19 Abnormal operation . 18
20 Stability and mechanical hazards . 23
21 Mechanical strength . 23
22 Construction . 24
23 Internal wiring . 29
24 Components . 29
25 Supply connection and external flexible cords . 30
26 Terminals for external conductors . 30
27 Provision for earthing . 30
28 Screws and connections . 30
29 Clearances, creepage distances and solid insulation . 30
30 Resistance to heat and fire . 31
31 Resistance to rusting . 32
32 Radiation, toxicity and similar hazards . 32
Annexes . 33
Annex C (normative) Ageing test on motors . 33
Annex D (normative) Thermal motor protectors . 33
Annex AA (normative) Running overload tests for motor-compressors classified as
tested with Annex AA . 34
Annex BB (normative) Winding wire insulation compatibility tests . 47
Annex CC (normative) Tie cords and insulation compatibility tests . 52

Annex DD (normative) Non-sparking “n” electrical apparatus and test condition for “dc”
devices . 55
Annex EE (normative) Fatigue test . 57
Bibliography . 59

Figure 101 – Supply circuit for the locked-rotor test of a single-phase motor-
compressor . 32
Figure AA.1 – Substitute refrigeration circuit . 46
Figure BB.1 – Motorette components . 50
Figure BB.2 – Completely assembled motorette . 51

Table 101 – Minimum high side test pressures . 25
Table 102 – Minimum low side test pressures . 27
Table AA.1 – Substitute refrigeration circuit conditions for operating under running
overload conditions .
Table AA.2 – Substitute refrigeration circuit conditions for operating under maximum
load conditions .
Table AA.3 – Steps for increasing the load on the motor-compressor .
Table AA.1 – Substitute refrigeration circuit conditions for operation under

maximum load . 44
Table AA.2 – Steps for increasing the load on the motor-compressor . 45
Table BB.1 – Time temperature heating cycles . 48
Table CC.1 – Time temperature heating cycles . 53

– 4 – IEC 60335-2-34:2021 RLV © IEC 2021
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
HOUSEHOLD AND SIMILAR ELECTRICAL APPLIANCES –
SAFETY –
Part 2-34: Particular requirements for motor-compressors

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their
preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
may participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence between
any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent
rights. IEC shall not be held responsible for identifying any or all such patent rights.
This redline version of the official IEC Standard allows the user to identify the changes made to
the previous edition IEC 60335-2-34:2012+AMD1:2015+AMD2:2016 CSV. A vertical bar appears
in the margin wherever a change has been made. Additions are in green text, deletions are in
strikethrough red text.
This part of IEC 60335 has been prepared by subcommittee 61C: Safety of refrigeration
appliances for household and commercial use, of IEC Technical Committee 61: Safety of
household and similar electrical appliances.
This sixth edition cancels and replaces the fifth edition published in 2012, Amendment 1:2015
and Amendment 2:2016. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
– it aligns the text with IEC 60335-1, Ed 5.2;
– application categories and tests have been extended (3.1.102, Annex AA);
– use of a motorette for winding wire compatibility tests introduced (3.8.102, Annex BB);
– height of the triangle, symbol ISO 7010 W021 has been introduced (7.14);
– some notes are converted to normative text (1, 15.3, 22.21, 23.8, 29.3.4, Figure AA.1);
– note in Subclause 6.101 becomes normative in Clause 11;
– optional pressure endurance test introduced (18.101, Annex EE);
– compatibility test for insulation inside the housing clarified (22.9);
– clarification of clearances inside the housing for motor-compressors suitable for use at
altitudes exceeding 2 000 m (29.1);
– normative references and associated text have been updated (24.101, Annex DD);
– breaking strength of tie cord after temperature heating cycle has been updated (Annex CC).
The text of this International Standard is based on the following documents:
Draft Report on voting
61C/873/FDIS 61C/874/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/standardsdev/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. It was established on the basis of the fifth edition (2010) 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: Safety requirements for motor-compressors.
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:

– 6 – IEC 60335-2-34:2021 RLV © IEC 2021
– 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 "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
NOTE 4 The attention of National Committees is drawn to the fact that equipment manufacturers and testing
organizations may 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.
It is the recommendation of the committee that the content of this publication be adopted for implementation nationally
not earlier than 12 months or later than 36 months from the date of publication.
The following differences exist in the countries indicated below.
– 7.1: The locked-rotor current marking is required for some motor-compressors (USA).
– 22.7: Different test pressures are used (Japan, USA).

IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this document using a colour printer.

INTRODUCTION
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.
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 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 and generic standards 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. For
example, in the case of temperature requirements for surfaces on many appliances, generic standards, such as
ISO 13732-1 for hot surfaces, are not applicable in addition to Part 1 or part 2 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.
If testing of the motor-compressor includes testing in accordance with Annex AA,
temperatures of the motor-compressor windings, housing and other parts related to the
motor-compressor, such as terminals, internal wiring and insulating materials, are not
measured when the complete appliance in which the motor-compressor is used is tested.
These requirements apply to sealed (hermetic and semi-hermetic type) motor-compressors
with their associated starting, cooling capacity control and protection systems, tested separately
under the most severe conditions of the refrigerating system operation which, within reasonable
limits, could occur in the applications for which they are used.
In particular, the construction detail inspection and locked-rotor testing may be done separately
on the motor-compressor, thereby eliminating the need for inspection and testing when the
motor-compressor is applied to many different appliances and factory-built assemblies.

– 8 – IEC 60335-2-34:2021 RLV © IEC 2021
Operational tests may also be conducted on the motor-compressor separately in certain
circumstances. The specification for this type testing is provided in Annex AA. However, the
tests of the existing standards relevant to the given kind of application, such as
IEC 60335-2-24 and IEC 60335-2-40, may need to be conducted on the final application and
used as the final determination of acceptability.

HOUSEHOLD AND SIMILAR ELECTRICAL APPLIANCES –
SAFETY –
Part 2-34: Particular requirements for motor-compressors

1 Scope
This clause of Part 1 is replaced by the following.
This part of IEC 60335 deals with the safety of sealed (hermetic and semi-hermetic type) motor-
compressors, their protection and control systems, if any, which are intended for use in
equipment for household and similar purposes and which conform with the standards applicable
to such equipment. It applies to motor-compressors tested separately, under the most severe
conditions that may be expected to occur in normal use, their rated voltage being not more
than 250 V for single-phase motor-compressors and 600 V for other motor-compressors.
This standard also covers
– multi-speed motor-compressors, that are motor-compressors, the speed of which can be
set to different values;
– variable capacity motor-compressors that are motor-compressors where the capacity of
the compressor is controlled at fixed speeds.
NOTE 101 Examples of equipment which contain motor-compressors are
– refrigerators, food freezers and ice makers (IEC 60335-2-24);
– air-conditioners, electric heat pumps and dehumidifiers (IEC 60335-2-40);
– commercial dispensing appliances and vending machines (IEC 60335-2-75);
– factory-built assemblies for transferring heat in applications for refrigerating, air-conditioning or heating purposes
or a combination of such purposes.
– tumble dryers (IEC 60335-2-11);
– refrigerating appliances, ice-cream appliances and ice-makers (IEC 60335-2-24);
– electrical heat pumps, air-conditioners and dehumidifiers (IEC 60335-2-40);
– commercial dispensing appliances and vending machines (IEC 60335-2-75);
– commercial refrigerating appliances and ice-makers with an incorporated or remote refrigerant unit or
compressor (IEC 60335-2-89);
– electrical equipment for measurement, control, and laboratory use (IEC 61010-2-011);
– professional ice-cream makers (IEC 60335-2-118);
– refrigerating systems and heat pumps (ISO 5149-2).
This standard does not supersede the requirements of standards relevant to the particular
appliance in which the motor-compressor is used. However, if the motor-compressor type
used complies with this standard, the tests for the motor-compressor specified in the particular
appliance standard may not need to be made in the particular appliance or assembly. If the
motor-compressor control system is associated with the particular appliance control system,
additional tests may could be necessary on the final appliance.
So far as is practical, this standard deals with the common hazards presented by motor-
compressors used in appliances which are encountered by all persons in and around the home.
However, it does not in general take into account
– the use of appliances by young children or infirm persons without supervision;
– playing with the appliances by young children.

– 10 – IEC 60335-2-34:2021 RLV © IEC 2021
NOTE 102 Attention is drawn to the fact that
– for motor-compressors intended to be used in appliances in vehicles or on board ships, additional requirements
may could be necessary;
– in many countries, additional requirements are specified by the national health authorities, the national
authorities responsible for the protection of labour and similar authorities.
NOTE 103 This standard does not apply to
– motor-compressors designed exclusively for industrial purposes;
– motor-compressors used in appliances intended to be used in locations where special
conditions prevail, such as the presence of a corrosive or explosive atmosphere (dust,
vapour or gas).
NOTE 104103 If motor-compressors for refrigerant R-744 used in appliances with a transcritical refrigeration
system are equipped with pressure relief devices, compliance with the requirements for these devices is checked
during the tests on the final appliance.
2 Normative references
This clause of Part 1 is applicable, except as follows.
Addition:
IEC 60079-1:2014, Explosive atmospheres – Part 1: Equipment protection by flameproof
enclosures "d"
IEC 60079-15:20102017, Explosive atmospheres – Part 15: Equipment protection by type of
protection ”n”
IEC 60851-4:2016, Methods of test for Winding wires – Test methods – Part 4: Chemical
properties
IEC 60851-5:2008, Winding wires – Test methods – Part 5: Electrical properties
IEC 60851-5:2008/AMD1:2011
IEC 60851-5:2008/AMD2:2019
ISO 817:2014, Refrigerants – Designation and safety classification
ISO 817:2014/AMD1:2017
ISO 7010:2019, Graphical symbols – Safety colours and safety signs – Registered safety signs
3 Terms and definitions
This clause of Part 1 is applicable, except as follows.
3.101
motor-compressor
appliance consisting of the mechanical mechanism of the compressor and the motor, both of
which are enclosed in the same sealed housing, with no external shaft seals, and with the
motor operating in a refrigerant atmosphere with or without oil
Note 1 to entry: The housing may be permanently sealed, such as by welding or brazing (hermetic motor-
compressor), or may be sealed by gasketted joints (semi-hermetic motor-compressor). A terminal box, a terminal
box cover, and other electrical components or an electronic control system may be included.
_____________
There exists a consolidated edition 4.2:2019 that includes Edition 4 and its Amendment 1 and Amendment 2.

Note 2 to entry: Hereafter, the term motor-compressor will be used to designate either a hermetic motor-
compressor or semi-hermetic motor-compressor.
3.102
housing
sealed enclosure for the motor-compressor, which contains the compressor mechanism and
the motor, and which is subjected to refrigerant pressures
3.103
thermal motor-protector
automatic control, built-in or fitted on a motor-compressor, that is specifically intended to
protect the motor-compressor against over-heating due to running overload and failure to start
Note 1 to entry: This control carries motor-compressor current and is sensitive to one or both of the following:
– motor-compressor temperature;
– motor-compressor current.
Note 2 to entry: The control is capable of being reset (either manually or automatically) when its temperature falls
to the reset value.
3.104
motor-compressor protection system
thermal motor protector and associated components, if any, or protective electronic circuit
fully or partly separate or integrated into the motor-compressor control system and which is
specifically intended to protect the motor-compressor against over-heating due to running
overload or failure to start
Note 1 to entry: The control carries motor-compressor current and is sensitive to one or both of the following:
– motor-compressor temperature;
– motor-compressor current.
3.105
motor-compressor control system
system comprising one or more electrical or electronic components, or electronic circuits
that provides at least one of the following:
– motor-compressor starting control functions;
– motor-compressor cooling capacity control functions
3.106
starting relay
electrically operated control device intended for integration or incorporation into a motor-
compressor and used within the motor-compressor circuit to control the starting of single-
phase motor-compressors
3.107
application category
back pressure relative to the evaporation temperature range over which the motor-compressor
operates
Note 1 to entry: For the purpose of this standard, the following classifications of application categories are made
relative to the evaporation temperature range:
– low back pressure (LBP): denotes an evaporation temperature range from –35 °C to
–15 °C;
– medium back pressure (MBP): denotes an evaporation temperature range from –20 °C to 0 °C;
– high back pressure (HBP): denotes an evaporation temperature range from –5 °C to +15 °C.
3.108
transcritical refrigeration system
refrigeration system where the pressure in the high pressure side is above the pressure where
the vapour and liquid states of the refrigerant can coexist in thermodynamic equilibrium

– 12 – IEC 60335-2-34:2021 RLV © IEC 2021
3.109
design pressure
gauge pressure that has been assigned to a transcritical refrigeration system
Note 1 to entry: It is specified for the high pressure side of a refrigeration system.
3 110
pressure relief device
pressure sensing device, intended to reduce pressure automatically when pressures within the
refrigeration system exceed the preset pressure of the device
Note 1 to entry: This device has no provisions for setting by the end user.
3.111
two-stage motor-compressor
motor-compressor comprising two compressors and one motor in a single housing
3.1 Definitions relating to physical characteristics
3.1.101
design pressure
gauge pressure that has been assigned to a transcritical refrigeration system
Note 1 to entry: It is specified for the high pressure side of a refrigeration system.
3.1.102
application category
back pressure relative to the evaporation temperature range over which the motor-compressor
operates
Note 1 to entry: For the purpose of this standard, the following classifications of application categories are made
relative to the maximum evaporation temperature:
– very low back pressure (VLBP): denotes a maximum evaporation temperature of –25 °C;
– low back pressure (LBP): denotes a maximum evaporation temperature of –15 °C;
– medium back pressure (MBP): denotes a maximum evaporation temperature of 0 °C;
– high back pressure (HBP): denotes a maximum evaporation temperature of +15 °C;
– very high back pressure (VHBP): denotes a maximum evaporation temperature of +30 °C;
– subcritical R-744 back pressure (SC R-744BP): denotes a maximum evaporation temperature of –15 °C;
3.5 Definitions relating to types of appliances
3.5.101
motor-compressor
appliance consisting of the mechanical mechanism of the compressor and the motor, both of
which are enclosed in the same sealed housing, with no external shaft seals, and with the
motor operating in a refrigerant atmosphere with or without oil
Note 1 to entry: The housing may be permanently sealed, such as by welding or brazing (hermetic motor-
compressor), or may be sealed by gasketed joints (semi-hermetic motor-compressor). A terminal box, a terminal
box cover, and other electrical components or an electronic control system may be included.
Note 2 to entry: Hereafter, the term motor-compressor will be used to designate either a hermetic motor-
compressor or semi-hermetic motor-compressor.
3.5.102
two-stage motor-compressor
motor-compressor comprising two compressors and one motor in a single housing

3.6 Definitions relating to parts of an appliance
3.6.101
housing
sealed enclosure for the motor-compressor, which contains the compressor mechanism and
the motor, and which is subjected to refrigerant pressures
3.6.102
starting relay
electrically operated control device intended for integration or incorporation into a motor-
compressor and used within the motor-compressor circuit to control the starting of single-
phase motor-compressors
3.7 Definitions relating to safety components
3.7.101
thermal motor-protector
automatic control, built-in or fitted on a motor-compressor that is specifically intended to
protect the motor-compressor against over-heating due to running overload and failure to start
Note 1 to entry: This control carries motor-compressor current and is sensitive to one or both of the following:
– motor-compressor temperature;
– motor-compressor current.
Note 2 to entry: The control is capable of being reset (either manually or automatically) when its temperature falls
to the reset value.
3.7.102
motor-compressor protection system
thermal motor protector and associated components, if any, or protective electronic circuit
fully or partly separate or integrated into the motor-compressor control system and which is
specifically intended to protect the motor-compressor against over-heating due to running
overload or failure to start
Note 1 to entry: The control carries motor-compressor current and is sensitive to one or both of the following:
– motor-compressor temperature;
– motor-compressor current.
3.7.103
motor-compressor control system
system comprising one or more electrical or electronic components, or electronic circuits
that provides at least one of the following:
– motor-compressor starting control functions;
– motor-compressor cooling capacity control functions
3 7.104
pressure relief device
pressure sensing device, intended to reduce pressure automatically when pressures within the
refrigeration system exceed the preset pressure of the device
Note 1 to entry: This device has no provisions for setting by the end user.
3.8 Definitions relating to miscellaneous matters
3.8.101
transcritical refrigeration system
refrigeration system where the pressure in the high pressure side is above the pressure where
the vapour and liquid states of the refrigerant can coexist in thermodynamic equilibrium

– 14 – IEC 60335-2-34:2021 RLV © IEC 2021
3.8.102
motorette
insulation system model made to embody all of the elements of a random wound insulation
system
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.
5.2 Addition:
At least one additional sample is required for the tests of Clause 19, however further samples
may also be provided or are needed.
For the test of 22.7, two samples of the housing are required.
5.6 Addition:
Variable speed motor-compressors shall run at maximum speed.
5.7 Replacement:
Tests are carried out in an ambient temperature of 20 °C ± 5 °C.
5.8.2 Addition:
Motor-compressors with self-resetting motor-compressor protection systems, and
designed for more than one rated voltage, are subjected to the tests of 19.101 and 19.103 at
the highest voltage.
5.10 Addition:
For the tests of Clause 19, the additional sample or samples shall be identical in all respects to
the test sample, charged with oil, if necessary, and vapour refrigerant. The sample has to be
provided with the motor-compressor protection system, starting relay, start capacitor, run
capacitor and control system, if any, as specified by the manufacturer, except that the rotor
shall have been locked by the manufacturer.
The manufacturer or responsible agent shall provide the following information for each type of
motor-compressor submitted for the tests:
– type (synthetic or cellulosic) of winding insulation;
– refrigerant identification:
a) for a single component refrigerant, by at least one of the following:
• chemical name;
• chemical formula;
• refrigerant number;
b) for a blended refrigerant, at least one of the following:
• chemical name and nominal proportion of each of the components;

• chemical formula and nominal proportion of each of the components;
• refrigerant number and nominal proportion of each of the components;
• refrigerant number of the refrigerant blend;
– types and quantity of oil to be used if the test samples which use oil are not already charged;
– application category or application categories for motor-compressors classified as being
tested with Annex AA;
– whether a supply cord can be connected directly to terminals on the motor-compressor;
– for motor-compressors intended for appliances with a transcritical refrigeration system, the
test pressure for the high pressure side if higher than the minimum test pressure.
5.11 Replacement:
For motor-compressors which can be used in appliances where the supply cord is connected
directly to terminals on the motor-compressor, the test sample shall be provided with a supply
cord.
NOTE 101 Any additional samples required for testing need not be provided with a supply cord.
5.101 Motor-compressors, including those with crank-case heaters, are tested as motor-
operated appliances.
5.102 With regard to 6.104, protective devices other than the declared device under test
shall be disabled during the tests of Annex AA and Clause 19. If multiple protective devices
are declared, each shall be tested independently.
5.103 For cascade systems comprising two or more motor-compressor circuits, each motor-
compressor circuit is tested separately in the end product. IEC 60335-2-34 is not applicable
for the system but each motor-compressor can be tested according to this standard.
6 Classification
This clause of Part 1 is applicable, except as follows.
6.101 Motor-compressors without an incorporated or associated electronic circuit are
classified as being tested with Annex AA or without Annex AA.
Motor-compressors with an incorporated or associated electronic circuit are classified as
being tested with Annex AA.
Motor-compressors can be classified as being tested with Annex AA only if the motor-
compressor in combination with the motor-compressor protection system or motor-
compressor control system, if any, can be configured to operate so as to deliver maximum
cooling capacity, independently of any input sensors that are only provided as part of the final
application.
NOTE Motor-compressors classified as being tested without Annex AA and their protection system or control
system, if any, are normally subjected to a heating test as a complete system in the final application in accordance
with the appropriate appliance standard.
Compliance is checked by
– the tests of this standard including the tests in Annex AA, for motor-compressors tested
with Annex AA;
– the tests of this standard but not including the tests in Annex AA, for motor-compressors
tested without Annex AA.
– 16 – IEC 60335-2-34:2021 RLV © IEC 2021
6.102 Motor compressors are classified as being
– intended for direct connection of the appliance supply cord to the motor-compressor
terminals, or
– not intended for direct connection of the appliance supply cord to the motor-compressor
terminals.
NOTE 1 Motor-compressors can in both cases be delivered with or without the external components necessary
for connection of the supply cord.
NOTE 2 Motor-compressors intended for direct connection of the appliance supply cord to their terminals can
also be used without the supply cord being connected directly to their terminals.
NOTE 3 If the motor-compressor is used without the relevant components or with components different from those
specified by the manufacturer, additional testing in accordance with the appropriate appliance standard can be
necessary.
Compliance is checked by inspection and by the relevant tests.
6.103 Motor-compressors are classified as being protected by protective electronic
circuits or not being protected by protective electronic circuits.
This does not preclude the protective electronic circuits being provided in the end product,
in which case many of the tests of this standard shall be conducted on the end product.
Compliance is checked by inspection and by the relevant tests.
6.104 The motor-compressor manufacturer shall declare the means of motor protection,
thermal motor protector, impedance protection, protective electronic circuit, or a
combination of the above.
Compliance is checked by inspection and by the relevant tests
6.105 Motor-compressors using refrigerant R744 shall be classified as used in a
transcritical refrigeration system or in a non-transcritical subcritical refrigeration system.
Compliance is checked by inspection and by the relevant tests
7 Marking and instructions
This clause of Part 1 is applicable, except as follows.
7.1 Modification:
The rated power input or rated current need not be marked.
Addition:
Motor-compressors suitable for use with a flammable refrigerant shall be marked with symbol
Warning sign ISO 7010 W021 (2011-05).
7.5 Not applicable.
7.6 Addition:
IEC 60335-2-34:20
...

IEC 60335-2-34 ®
Edition 6.0 2021-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Household and similar electrical appliances – Safety –
Part 2-34: Particular requirements for motor-compressors

Appareils électrodomestiques et analogues – Sécurité –
Partie 2-34: Exigences particulières pour les motocompresseurs
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local IEC member National Committee for further information.

Droits de reproduction réservés. Sauf indication contraire, aucune partie de cette publication ne peut être reproduite
ni utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie
et les microfilms, sans l'accord écrit de l'IEC ou du Comité national de l'IEC du pays du demandeur. Si vous avez des
questions sur le copyright de l'IEC ou si vous désirez obtenir des droits supplémentaires sur cette publication, utilisez
les coordonnées ci-après ou contactez le Comité national de l'IEC de votre pays de résidence.

IEC Central Office Tel.: [phone]
3, rue de Varembé [e-mail]
CH-1211 Geneva 20 www.iec.ch
Switzerland
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

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

IEC publications search - webstore.iec.ch/advsearchform IEC online collection - oc.iec.ch
The advanced search enables to find IEC publications by a Discover our powerful search engine and read freely all the
variety of criteria (reference number, text, technical publications previews. With a subscription you will always
committee, …). It also gives information on projects, replaced have access to up to date content tailored to your needs.
and withdrawn publications.
Electropedia - www.electropedia.org
IEC Just Published - webstore.iec.ch/justpublished
The world's leading online dictionary on electrotechnology,
Stay up to date on all new IEC publications. Just Published
containing more than 22 000 terminological entries in English
details all new publications released. Available online and
and French, with equivalent terms in 18 additional languages.
once a month by email.
Also known as the International Electrotechnical Vocabulary

(IEV) online.
IEC Customer Service Centre - webstore.iec.ch/csc
If you wish to give us your feedback on this publication or
need further assistance, please contact the Customer Service
Centre: [e-mail].
A propos de l'IEC
La Commission Electrotechnique Internationale (IEC) est la première organisation mondiale qui élabore et publie des
Normes internationales pour tout ce qui a trait à l'électricité, à l'électronique et aux technologies apparentées.

A propos des publications IEC
Le contenu technique des publications IEC est constamment revu. Veuillez vous assurer que vous possédez l’édition la
plus récente, un corrigendum ou amendement peut avoir été publié.

Recherche de publications IEC - IEC online collection - oc.iec.ch
webstore.iec.ch/advsearchform Découvrez notre puissant moteur de recherche et consultez
La recherche avancée permet de trouver des publications IEC gratuitement tous les aperçus des publications. Avec un
en utilisant différents critères (numéro de référence, texte, abonnement, vous aurez toujours accès à un contenu à jour
comité d’études, …). Elle donne aussi des informations sur adapté à vos besoins.
les projets et les publications remplacées ou retirées.

Electropedia - www.electropedia.org
IEC Just Published - webstore.iec.ch/justpublished
Le premier dictionnaire d'électrotechnologie en ligne au
Restez informé sur les nouvelles publications IEC. Just
monde, avec plus de 22 000 articles terminologiques en
Published détaille les nouvelles publications parues.
anglais et en français, ainsi que les termes équivalents dans
Disponible en ligne et une fois par mois par email.
16 langues additionnelles. Egalement appelé Vocabulaire

Electrotechnique International (IEV) en ligne.
Service Clients - webstore.iec.ch/csc

Si vous désirez nous donner des commentaires sur cette
publication ou si vous avez des questions contactez-nous:
[e-mail].
IEC 60335-2-34 ®
Edition 6.0 2021-03
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Household and similar electrical appliances – Safety –

Part 2-34: Particular requirements for motor-compressors

Appareils électrodomestiques et analogues – Sécurité –

Partie 2-34: Exigences particulières pour les motocompresseurs

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 97.040.30 ISBN 978-2-8322-9432-1

– 2 – IEC 60335-2-34:2021 © IEC 2021
CONTENTS
FOREWORD . 4
INTRODUCTION . 7
1 Scope . 9
2 Normative references . 10
3 Terms and definitions . 10
4 General requirement . 12
5 General conditions for the tests . 12
6 Classification . 13
7 Marking and instructions . 14
8 Protection against access to live parts . 15
9 Starting of motor-operated appliances . 15
10 Power input and current . 15
11 Heating . 15
12 Void . 16
13 Leakage current and electric strength at operating temperature . 16
14 Transient overvoltages . 16
15 Moisture resistance . 16
16 Leakage current and electric strength . 16
17 Overload protection of transformers and associated circuits . 16
18 Endurance . 16
19 Abnormal operation . 16
20 Stability and mechanical hazards . 22
21 Mechanical strength . 22
22 Construction . 22
23 Internal wiring . 25
24 Components . 26
25 Supply connection and external flexible cords . 26
26 Terminals for external conductors . 26
27 Provision for earthing . 26
28 Screws and connections . 26
29 Clearances, creepage distances and solid insulation . 26
30 Resistance to heat and fire . 28
31 Resistance to rusting . 28
32 Radiation, toxicity and similar hazards . 28
Annexes . 29
Annex C (normative) Ageing test on motors . 29
Annex D (normative) Thermal motor protectors . 29
Annex AA (normative) Running overload tests for motor-compressors classified as
tested with Annex AA . 30
Annex BB (normative) Winding wire insulation compatibility tests . 34
Annex CC (normative) Tie cords and insulation compatibility tests . 38

Annex DD (normative) Non-sparking “n” electrical apparatus and test condition for “dc”
devices . 40
Annex EE (normative) Fatigue test . 41
Bibliography . 43

Figure 101 – Supply circuit for the locked-rotor test of a single-phase motor-
compressor . 28
Figure AA.1 – Substitute refrigeration circuit . 33
Figure BB.1 – Motorette components . 36
Figure BB.2 – Completely assembled motorette . 37

Table 101 – Minimum high side test pressures . 23
Table 102 – Minimum low side test pressures . 24
Table AA.1 – Substitute refrigeration circuit conditions for operation under
maximum load . 31
Table AA.2 – Steps for increasing the load on the motor-compressor . 32
Table BB.1 – Time temperature heating cycles . 35
Table CC.1 – Time temperature heating cycles . 39

– 4 – IEC 60335-2-34:2021 © IEC 2021
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
HOUSEHOLD AND SIMILAR ELECTRICAL APPLIANCES –
SAFETY –
Part 2-34: Particular requirements for motor-compressors

FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote international
co-operation on all questions concerning standardization in the electrical and electronic fields. To this end and
in addition to other activities, IEC publishes International Standards, Technical Specifications, Technical Reports,
Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC Publication(s)”). Their
preparation is entrusted to technical committees; any IEC National Committee interested in the subject dealt with
may participate in this preparatory work. International, governmental and non-governmental organizations liaising
with the IEC also participate in this preparation. IEC collaborates closely with the International Organization for
Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence between
any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of patent
rights. IEC shall not be held responsible for identifying any or all such patent rights.
This part of IEC 60335 has been prepared by subcommittee 61C: Safety of refrigeration
appliances for household and commercial use, of IEC Technical Committee 61: Safety of
household and similar electrical appliances.
This sixth edition cancels and replaces the fifth edition published in 2012, Amendment 1:2015
and Amendment 2:2016. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
– it aligns the text with IEC 60335-1, Ed 5.2;
– application categories and tests have been extended (3.1.102, Annex AA);
– use of a motorette for winding wire compatibility tests introduced (3.8.102, Annex BB);
– height of the triangle, symbol ISO 7010 W021 has been introduced (7.14);
– some notes are converted to normative text (1, 15.3, 22.21, 23.8, 29.3.4, Figure AA.1);

– note in Subclause 6.101 becomes normative in Clause 11;
– optional pressure endurance test introduced (18.101, Annex EE);
– compatibility test for insulation inside the housing clarified (22.9);
– clarification of clearances inside the housing for motor-compressors suitable for use at
altitudes exceeding 2 000 m (29.1);
– normative references and associated text have been updated (24.101, Annex DD);
– breaking strength of tie cord after temperature heating cycle has been updated (Annex CC).
The text of this International Standard is based on the following documents:
Draft Report on voting
61C/873/FDIS 61C/874/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/standardsdev/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. It was established on the basis of the fifth edition (2010) 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: Safety requirements for motor-compressors.
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.

– 6 – IEC 60335-2-34:2021 © IEC 2021
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
NOTE 4 The attention of National Committees is drawn to the fact that equipment manufacturers and testing
organizations may 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.
It is the recommendation of the committee that the content of this publication be adopted for implementation nationally
not earlier than 12 months or later than 36 months from the date of publication.
The following differences exist in the countries indicated below.
– 7.1: The locked-rotor current marking is required for some motor-compressors (USA).
– 22.7: Different test pressures are used (Japan, USA).

IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this document using a colour printer.

INTRODUCTION
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.
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 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 and generic standards 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. For
example, in the case of temperature requirements for surfaces on many appliances, generic standards, such as
ISO 13732-1 for hot surfaces, are not applicable in addition to Part 1 or part 2 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.
If testing of the motor-compressor includes testing in accordance with Annex AA,
temperatures of the motor-compressor windings, housing and other parts related to the
motor-compressor, such as terminals, internal wiring and insulating materials, are not
measured when the complete appliance in which the motor-compressor is used is tested.
These requirements apply to sealed (hermetic and semi-hermetic type) motor-compressors
with their associated starting, cooling capacity control and protection systems, tested separately
under the most severe conditions of the refrigerating system operation which, within reasonable
limits, could occur in the applications for which they are used.
In particular, the construction detail inspection and locked-rotor testing may be done separately
on the motor-compressor, thereby eliminating the need for inspection and testing when the
motor-compressor is applied to many different appliances and factory-built assemblies.

– 8 – IEC 60335-2-34:2021 © IEC 2021
Operational tests may also be conducted on the motor-compressor separately in certain
circumstances. The specification for this type testing is provided in Annex AA. However, the
tests of the existing standards relevant to the given kind of application, such as
IEC 60335-2-24 and IEC 60335-2-40, may need to be conducted on the final application and
used as the final determination of acceptability.

HOUSEHOLD AND SIMILAR ELECTRICAL APPLIANCES –
SAFETY –
Part 2-34: Particular requirements for motor-compressors

1 Scope
This clause of Part 1 is replaced by the following.
This part of IEC 60335 deals with the safety of sealed (hermetic and semi-hermetic type) motor-
compressors, their protection and control systems, if any, which are intended for use in
equipment for household and similar purposes and which conform with the standards applicable
to such equipment. It applies to motor-compressors tested separately, under the most severe
conditions that may be expected to occur in normal use, their rated voltage being not more
than 250 V for single-phase motor-compressors and 600 V for other motor-compressors.
This standard also covers
– multi-speed motor-compressors, that are motor-compressors, the speed of which can be
set to different values;
– variable capacity motor-compressors that are motor-compressors where the capacity of
the compressor is controlled at fixed speeds.
NOTE 101 Examples of equipment which contain motor-compressors are
– tumble dryers (IEC 60335-2-11);
– refrigerating appliances, ice-cream appliances and ice-makers (IEC 60335-2-24);
– electrical heat pumps, air-conditioners and dehumidifiers (IEC 60335-2-40);
– commercial dispensing appliances and vending machines (IEC 60335-2-75);
– commercial refrigerating appliances and ice-makers with an incorporated or remote refrigerant unit or
compressor (IEC 60335-2-89);
– electrical equipment for measurement, control, and laboratory use (IEC 61010-2-011);
– professional ice-cream makers (IEC 60335-2-118);
– refrigerating systems and heat pumps (ISO 5149-2).
This standard does not supersede the requirements of standards relevant to the particular
appliance in which the motor-compressor is used. However, if the motor-compressor type
used complies with this standard, the tests for the motor-compressor specified in the particular
appliance standard may not need to be made in the particular appliance or assembly. If the
motor-compressor control system is associated with the particular appliance control system,
additional tests could be necessary on the final appliance.
So far as is practical, this standard deals with the common hazards presented by motor-
compressors used in appliances which are encountered by all persons in and around the home.
However, it does not in general take into account
– the use of appliances by young children or infirm persons without supervision;
– playing with the appliances by young children.
NOTE 102 Attention is drawn to the fact that
– for motor-compressors intended to be used in appliances in vehicles or on board ships, additional requirements
could be necessary;
– in many countries, additional requirements are specified by the national health authorities, the national
authorities responsible for the protection of labour and similar authorities.

– 10 – IEC 60335-2-34:2021 © IEC 2021
This standard does not apply to
– motor-compressors designed exclusively for industrial purposes;
– motor-compressors used in appliances intended to be used in locations where special
conditions prevail, such as the presence of a corrosive or explosive atmosphere (dust,
vapour or gas).
NOTE 103 If motor-compressors for refrigerant R-744 used in appliances with a transcritical refrigeration
system are equipped with pressure relief devices, compliance with the requirements for these devices is checked
during the tests on the final appliance.
2 Normative references
This clause of Part 1 is applicable, except as follows.
Addition:
IEC 60079-1:2014, Explosive atmospheres – Part 1: Equipment protection by flameproof
enclosures "d"
IEC 60079-15:2017, Explosive atmospheres – Part 15: Equipment protection by type of
protection ”n”
IEC 60851-4:2016, Winding wires – Test methods – Part 4: Chemical properties
IEC 60851-5:2008, Winding wires – Test methods – Part 5: Electrical properties
IEC 60851-5:2008/AMD1:2011
IEC 60851-5:2008/AMD2:2019
ISO 817:2014, Refrigerants – Designation and safety classification
ISO 817:2014/AMD1:2017
ISO 7010:2019, Graphical symbols – Safety colours and safety signs – Registered safety signs
3 Terms and definitions
This clause of Part 1 is applicable, except as follows.
3.1 Definitions relating to physical characteristics
3.1.101
design pressure
gauge pressure that has been assigned to a transcritical refrigeration system
Note 1 to entry: It is specified for the high pressure side of a refrigeration system.
3.1.102
application category
back pressure relative to the evaporation temperature range over which the motor-compressor
operates
Note 1 to entry: For the purpose of this standard, the following classifications of application categories are made
relative to the maximum evaporation temperature:
– very low back pressure (VLBP): denotes a maximum evaporation temperature of –25 °C;
_____________
There exists a consolidated edition 4.2:2019 that includes Edition 4 and its Amendment 1 and Amendment 2.

– low back pressure (LBP): denotes a maximum evaporation temperature of –15 °C;
– medium back pressure (MBP): denotes a maximum evaporation temperature of 0 °C;
– high back pressure (HBP): denotes a maximum evaporation temperature of +15 °C;
– very high back pressure (VHBP): denotes a maximum evaporation temperature of +30 °C;
– subcritical R-744 back pressure (SC R-744BP): denotes a maximum evaporation temperature of –15 °C;
3.5 Definitions relating to types of appliances
3.5.101
motor-compressor
appliance consisting of the mechanical mechanism of the compressor and the motor, both of
which are enclosed in the same sealed housing, with no external shaft seals, and with the
motor operating in a refrigerant atmosphere with or without oil
Note 1 to entry: The housing may be permanently sealed, such as by welding or brazing (hermetic motor-
compressor), or may be sealed by gasketed joints (semi-hermetic motor-compressor). A terminal box, a terminal
box cover, and other electrical components or an electronic control system may be included.
Note 2 to entry: Hereafter, the term motor-compressor will be used to designate either a hermetic motor-
compressor or semi-hermetic motor-compressor.
3.5.102
two-stage motor-compressor
motor-compressor comprising two compressors and one motor in a single housing
3.6 Definitions relating to parts of an appliance
3.6.101
housing
sealed enclosure for the motor-compressor, which contains the compressor mechanism and
the motor, and which is subjected to refrigerant pressures
3.6.102
starting relay
electrically operated control device intended for integration or incorporation into a motor-
compressor and used within the motor-compressor circuit to control the starting of single-
phase motor-compressors
3.7 Definitions relating to safety components
3.7.101
thermal motor-protector
automatic control, built-in or fitted on a motor-compressor that is specifically intended to
protect the motor-compressor against over-heating due to running overload and failure to start
Note 1 to entry: This control carries motor-compressor current and is sensitive to one or both of the following:
– motor-compressor temperature;
– motor-compressor current.
Note 2 to entry: The control is capable of being reset (either manually or automatically) when its temperature falls
to the reset value.
3.7.102
motor-compressor protection system
thermal motor protector and associated components, if any, or protective electronic circuit
fully or partly separate or integrated into the motor-compressor control system and which is
specifically intended to protect the motor-compressor against over-heating due to running
overload or failure to start
Note 1 to entry: The control carries motor-compressor current and is sensitive to one or both of the following:
– motor-compressor temperature;

– 12 – IEC 60335-2-34:2021 © IEC 2021
– motor-compressor current.
3.7.103
motor-compressor control system
system comprising one or more electrical or electronic components, or electronic circuits
that provides at least one of the following:
– motor-compressor starting control functions;
– motor-compressor cooling capacity control functions
3 7.104
pressure relief device
pressure sensing device, intended to reduce pressure automatically when pressures within the
refrigeration system exceed the preset pressure of the device
Note 1 to entry: This device has no provisions for setting by the end user.
3.8 Definitions relating to miscellaneous matters
3.8.101
transcritical refrigeration system
refrigeration system where the pressure in the high pressure side is above the pressure where
the vapour and liquid states of the refrigerant can coexist in thermodynamic equilibrium
3.8.102
motorette
insulation system model made to embody all of the elements of a random wound insulation
system
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.
5.2 Addition:
At least one additional sample is required for the tests of Clause 19, however further samples
may also be provided or are needed.
For the test of 22.7, two samples of the housing are required.
5.6 Addition:
Variable speed motor-compressors shall run at maximum speed.
5.7 Replacement:
Tests are carried out in an ambient temperature of 20 °C ± 5 °C.
5.8.2 Addition:
Motor-compressors with self-resetting motor-compressor protection systems, and
designed for more than one rated voltage, are subjected to the tests of 19.101 and 19.103 at
the highest voltage.
5.10 Addition:
For the tests of Clause 19, the additional sample or samples shall be identical in all respects to
the test sample, charged with oil, if necessary, and vapour refrigerant. The sample has to be
provided with the motor-compressor protection system, starting relay, start capacitor, run
capacitor and control system, if any, as specified by the manufacturer, except that the rotor
shall have been locked by the manufacturer.
The manufacturer or responsible agent shall provide the following information for each type of
motor-compressor submitted for the tests:
– type (synthetic or cellulosic) of winding insulation;
– refrigerant identification:
a) for a single component refrigerant, by at least one of the following:
• chemical name;
• chemical formula;
• refrigerant number;
b) for a blended refrigerant, at least one of the following:
• chemical name and nominal proportion of each of the components;
• chemical formula and nominal proportion of each of the components;
• refrigerant number and nominal proportion of each of the components;
• refrigerant number of the refrigerant blend;
– types and quantity of oil to be used if the test samples which use oil are not already charged;
– application category or application categories for motor-compressors classified as being
tested with Annex AA;
– whether a supply cord can be connected directly to terminals on the motor-compressor;
– for motor-compressors intended for appliances with a transcritical refrigeration system, the
test pressure for the high pressure side if higher than the minimum test pressure.
5.11 Replacement:
For motor-compressors which can be used in appliances where the supply cord is connected
directly to terminals on the motor-compressor, the test sample shall be provided with a supply
cord.
NOTE 101 Any additional samples required for testing need not be provided with a supply cord.
5.101 Motor-compressors, including those with crank-case heaters, are tested as motor-
operated appliances.
5.102 With regard to 6.104, protective devices other than the declared device under test
shall be disabled during the tests of Annex AA and Clause 19. If multiple protective devices
are declared, each shall be tested independently.
5.103 For cascade systems comprising two or more motor-compressor circuits, each motor-
compressor circuit is tested separately in the end product. IEC 60335-2-34 is not applicable
for the system but each motor-compressor can be tested according to this standard.
6 Classification
This clause of Part 1 is applicable, except as follows.

– 14 – IEC 60335-2-34:2021 © IEC 2021
6.101 Motor-compressors without an incorporated or associated electronic circuit are
classified as being tested with Annex AA or without Annex AA.
Motor-compressors with an incorporated or associated electronic circuit are classified as
being tested with Annex AA.
Motor-compressors can be classified as being tested with Annex AA only if the motor-
compressor in combination with the motor-compressor protection system or motor-
compressor control system, if any, can be configured to operate so as to deliver maximum
cooling capacity, independently of any input sensors that are only provided as part of the final
application.
6.102 Motor compressors are classified as being
– intended for direct connection of the appliance supply cord to the motor-compressor
terminals, or
– not intended for direct connection of the appliance supply cord to the motor-compressor
terminals.
NOTE 1 Motor-compressors can in both cases be delivered with or without the external components necessary
for connection of the supply cord.
NOTE 2 Motor-compressors intended for direct connection of the appliance supply cord to their terminals can
also be used without the supply cord being connected directly to their terminals.
NOTE 3 If the motor-compressor is used without the relevant components or with components different from those
specified by the manufacturer, additional testing in accordance with the appropriate appliance standard can be
necessary.
Compliance is checked by inspection and by the relevant tests.
6.103 Motor-compressors are classified as being protected by protective electronic
circuits or not being protected by protective electronic circuits.
This does not preclude the protective electronic circuits being provided in the end product,
in which case many of the tests of this standard shall be conducted on the end product.
Compliance is checked by inspection and by the relevant tests.
6.104 The motor-compressor manufacturer shall declare the means of motor protection,
thermal motor protector, impedance protection, protective electronic circuit, or a
combination of the above.
Compliance is checked by inspection and by the relevant tests
6.105 Motor-compressors using refrigerant R744 shall be classified as used in a
transcritical refrigeration system or in a subcritical refrigeration system.
Compliance is checked by inspection and by the relevant tests
7 Marking and instructions
This clause of Part 1 is applicable, except as follows.
7.1 Modification:
The rated power input or rated current need not be marked.

Addition:
Motor-compressors suitable for use with a flammable refrigerant shall be marked with Warning
sign ISO 7010 W021 (2011-05).
7.5 Not applicable.
7.6 Addition:
[warning sign ISO 7010 W021
Warning; Risk of fire / Flammable material
(2011-05)]
7.7 Not applicable.
7.12 Not applicable, except 7.12.1, which is applicable.
7.13 Not applicable.
7.14 Addition:
The height of the triangle in the symbol ISO 7010 W021 (2011-05) shall be at least 15 mm.
7.101 Refrigerants that can be used with the motor-compressor shall be listed in the
instructions.
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 not applicable.
11 Heating
This clause of Part 1 is replaced by Annex AA. For motor compressors classified as tested
without Annex AA, compliance with this clause shall be tested as a complete system in the final
application in accordance with the appropriate appliance standard.

– 16 – IEC 60335-2-34:2021 © IEC 2021
12 Void
13 Leakage current and electric strength at operating temperature
This clause of Part 1 is not applicable, except 13.3 as required by 19.104.
13.3 Addition:
In Table 4, add the following to table footnote a:
The test voltage for 600 V multi-phase appliances is that specified for a working voltage > 250 V where U is taken
as the rated voltage.
14 Transient overvoltages
This clause of Part 1 is applicable.
15 Moisture resistance
This clause of Part 1 is applicable, except as follows.
15.3 Addition:
The requirement shall be applied to motor-compressors not provided with glass-insulated
terminals but intended for connection to external control devices, protectors or other
components.
16 Leakage current and electric strength
This clause of Part 1 is applicable except as follows.
16.3 Addition:
In Table 7, add the following to table footnote a:
The test voltage for 600 V multi-phase appliances is that specified for a working voltage > 250 V where U is taken
as the rated voltage.
17 Overload protection of transformers and associated circuits
This clause of Part 1 is applicable.
18 Endurance
This clause of Part 1 is applicable, except as follows.
18.101 If requested by the manufacturer, the fatigue test specified in Annex EE shall be
carried out.
19 Abnormal operation
This clause of Part 1 is applicable, except as follows.

19.1 Modification:
Replace the test specification by the following:
Motor-compressors are submitted to the tests of 19.14, 19.15, 19.101, 19.102, 19.103 and,
additionally, if so required by the classification of 6.101, to the tests specified in Annex AA.
Motor-compressors incorporating electronic circuits are also subjected to the tests of 19.11
and 19.12.
Only one abnormal condition is simulated each time.
Compliance with the tests of 19.11 and 19.12 is checked as described in 19.13. Compliance
with the tests of 19.101, 19.102 and 19.103 is checked as described in 19.104. Compliance
with the tests of Annex AA is checked as described in An
...