prEN IEC 60335-2-34:2026

• Abstract:

  This European Standard 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 480 V for other motor-compressors

• Status: Not Published
• Publication Date: 26-Sep-2027
• ICS: 97.040.30 - Domestic refrigerating appliances
• Technical Committee: CLC/TC 61 - Safety of household and similar electrical appliances
• Drafting Committee: CLC/TC 61/WG 01 - Relation with standardization and legislation
• Current Stage: 4020 - Enquiry circulated - Enquiry
• Start Date: 16-Oct-2026
• Due Date: 24-Apr-2026
• Completion Date: 16-Oct-2026
• Directive: 2014/35/EU - Directive 2014/35/EU of the European Parliament and of the Council of 26 February 2014 on the harmonisation of the laws of the Member States relating to the making available on the market of electrical equipment designed for use within certain voltage limits
• Directive:

  ---

  2014/53/EU - Directive 2014/53/EU of The European Parliament and of the Council of 16 April 2014 on the harmonisation of the laws of the Member States relating to the making available on the market of radio equipment and repealing Directive 1999/5/EC
• Directive:

  ---

  2023/1230 - Regulation (EU) 2023/1230 of the European Parliament and of the Council of 14 June 2023 on machinery and repealing Directive 2006/42/EC of the European Parliament and of the Council and Council Directive 73/361/EEC (Text with EEA relevance)
• Mandate: M/511 - Mandate to CEN, CENELEC and ETSI relating to harmonised standards in the field of the Low Voltage Directive
• Mandate: M/536 - [C(2015)536] Standardisation request as regards radio equipment in support of Directive 2014/53/EU
• Mandate: M/605 - COMMISSION IMPLEMENTING DECISION of 20.1.2025 on a standardisation request to the European Committee for Standardization and to the European Committee for Electrotechnical Standardization as regards machinery and related products in support of Regulation (EU) 2023/1230 of the European Parliament and of the Council
• Ref Project: oSIST prEN IEC 60335-2-34:2026 - Household and similar electrical appliances - Safety - Part 2-34: Particular requirements for motor-compressors

• Referred By: prEN IEC 60335-2-118:2026 - Household and similar electrical appliances - Safety - Part 2-118: Particular requirements for professional ice-cream makers
• Effective Date: 25-Aug-2026
• Referred By: prEN IEC 60335-2-24:2026 - Household and similar electrical appliances - Safety - Part 2-24: Particular requirements for refrigerating appliances, ice-cream appliances and ice makers
• Effective Date: 18-Aug-2026
• Amended By: prEN IEC 60335-2-34:2026/prAA:2026 - Household and similar electrical appliances - Safety - Part 2-34: Particular requirements for motor-compressors
• Effective Date: 07-Apr-2025
• Revises: EN IEC 60335-2-34:2023 - Household and similar electrical appliances - Safety - Part 2-34: Particular requirements for motor-compressors
• Effective Date: 07-Apr-2025
• Revises: EN IEC 60335-2-34:2023/A11:2023 - Household and similar electrical appliances - Safety - Part 2-34: Particular requirements for motor-compressors
• Effective Date: 07-Apr-2025
• Revises: EN IEC 60335-2-34:2023/A12:2025 - Household and similar electrical appliances - Safety - Part 2-34: Particular requirements for motor-compressors
• Effective Date: 07-Apr-2025

SLOVENSKI STANDARD
01-december-2026
Gospodinjski in podobni električni aparati - Varnost - 2-34. del: Posebne zahteve
za motorne kompresorje
Household and similar electrical appliances - Safety - Part 2-34: Particular requirements
for motor-compressors
Sicherheit elektrischer Geräte für den Hausgebrauch und ähnliche Zwecke - Teil 2-34:
Besondere Anforderungen für Motorverdichter
Appareils électrodomestiques et analogues - Sécurité - Partie 2-34: Exigences
particulières pour les motocompresseurs
Ta slovenski standard je istoveten z: prEN IEC 60335-2-34:2026
ICS:
13.120 Varnost na domu Domestic safety
23.140 Kompresorji in pnevmatični Compressors and pneumatic
stroji machines
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD DRAFT
prEN IEC 60335-2-34
NORME EUROPÉENNE
EUROPÄISCHE NORM
October 2026
ICS 97.040.30 Will supersede EN IEC 60335-2-34:2023; EN IEC 60335-
2-34:2023/A11:2023; EN IEC 60335-2-34:2023/A12:2025
English Version
Household and similar electrical appliances - Safety - Part 2-34:
Particular requirements for motor-compressors
(IEC 60335-2-34:2024)
Appareils électrodomestiques et analogues - Sécurité - Sicherheit elektrischer Geräte für den Hausgebrauch und
Partie 2-34: Exigences particulières pour les ähnliche Zwecke - Teil 2-34: Besondere Anforderungen für
motocompresseurs Motorverdichter
(IEC 60335-2-34:2024) (IEC 60335-2-34:2024)
This draft European Standard is submitted to CENELEC members for enquiry.
Deadline for CENELEC: 2027-01-08.

The text of this draft consists of the text of IEC 60335-2-34:2024.

If this draft becomes a European Standard, CENELEC members are bound to comply with the CEN/CENELEC Internal Regulations which
stipulate the conditions for giving this European Standard the status of a national standard without any alteration.

This draft European Standard was established by CENELEC in three official versions (English, French, German).
A version in any other language made by translation under the responsibility of a CENELEC member into its own language and notified to
the CEN-CENELEC Management Centre has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the
Netherlands, Norway, Poland, Portugal, Republic of North Macedonia, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden, Switzerland,
Türkiye and the United Kingdom.

Recipients of this draft are invited to submit, with their comments, notification of any relevant patent rights of which they are aware and to
provide supporting documentation.

Warning : This document is not a European Standard. It is distributed for review and comments. It is subject to change without notice and
shall not be referred to as a European Standard.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2026 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Project: 81707 Ref. No. prEN IEC 60335-2-34:2026 E

European foreword
This document (prEN IEC 60335-2-34:2026) consists of the text of document IEC 60335-2-34:2024,
prepared by IEC/TC 61 "Safety of household and similar electrical appliances".
This document is currently submitted to the Enquiry.
The following dates are proposed:
• latest date by which the existence of this document (doa) dav + 6 months
has to be announced at national level
• latest date by which this document has to be (dop) dav + 12 months
implemented at national level by publication of an
identical national standard or by endorsement
• latest date by which the national standards (dow) dav + 36 months
conflicting with this document have to be withdrawn (to be confirmed or
modified when voting)
This document will supersede EN IEC 60335-2-34:2023 and all of its amendments and corrigenda (if
any).
This document is read in conjunction with prEN IEC 60335-2-34:2026/prAA:2026.

IEC 60335-2-34 ®
Edition 7.0 2024-11
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 978-2-8327-0017-4

– 2 – IEC 60335-2-34:2024 © IEC 2024
CONTENTS
FOREWORD . 4
INTRODUCTION . 7
1 Scope . 9
2 Normative references . 10
3 Terms and definitions . 10
4 General requirement . 13
5 General conditions for the tests . 13
6 Classification . 14
7 Marking and instructions . 15
8 Protection against access to live parts . 16
9 Starting of motor-operated appliances . 16
10 Power input and current . 16
11 Heating . 16
12 Charging of metal-ion batteries . 16
13 Leakage current and electric strength at operating temperature . 16
14 Transient overvoltages . 16
15 Moisture resistance . 17
16 Leakage current and electric strength . 17
17 Overload protection of transformers and associated circuits . 17
18 Endurance . 17
19 Abnormal operation . 17
20 Stability and mechanical hazards . 23
21 Mechanical strength . 23
22 Construction . 23
23 Internal wiring . 27
24 Components . 27
25 Supply connection and external flexible cords . 27
26 Terminals for external conductors . 27
27 Provision for earthing . 28
28 Screws and connections . 28
29 Clearances, creepage distances and solid insulation . 28
30 Resistance to heat and fire . 29
31 Resistance to rusting . 29
32 Radiation, toxicity and similar hazards . 29
Annexes . 30
Annex C (normative) Ageing test on motors . 30
Annex D (normative) Thermal motor-protectors . 30
Annex AA (normative) Running overload tests for motor-compressors classified as
tested with Annex AA . 31
Annex BB (normative) Winding wire insulation compatibility tests . 37
Annex CC (normative) Tie cords and insulation compatibility tests . 39

IEC 60335-2-34:2024 © IEC 2024 – 3 –
Annex DD (normative) Non-sparking "n" electrical apparatus and test condition for
"dc" devices . 41
Annex EE (normative) Fatigue test . 42
Annex FF (normative) Motorette or coilette compatibility test . 43
Bibliography . 48

Figure 101 – Supply circuit for the locked-rotor test of a single-phase motor-

compressor . 29
Figure AA.1 – Substitute refrigeration circuit . 36
Figure FF.1 – Motorette components . 45
Figure FF.2 – Coilette components . 46
Figure FF.3 – Completely assembled motorette . 47
Figure FF.4 – Completely assembled coilette . 47

Table 101 – Minimum high side test pressures . 24
Table 102 – Minimum low side test pressures . 25
Table AA.1 – Substitute refrigeration circuit conditions for operation under
maximum load . 32
Table AA.2 – Steps for increasing the load on the motor-compressor . 35
Table BB.1 – Time temperature heating cycles . 38

– 4 – IEC 60335-2-34:2024 © IEC 2024
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) 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 60335-2-34 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. It is an International Standard.
This seventh edition cancels and replaces the sixth edition published in 2021. 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) in the scope added the rating up to 600 V (Clause 1);

IEC 60335-2-34:2024 © IEC 2024 – 5 –
c) the definition of design pressure has been changed in maximum allowable pressure
(3.1.101, 7.102, 22.7);
d) introduction of maximum load conditions (MLC) as declared by the manufacturer (3.1.103,
5.6, 7.12, Annex AA);
e) transcritical back pressure categories (R-744) have been introduced (3.1.102, Table AA.1,
Table AA.2);
f) new definition of coilette has been introduced (3.8.103);
g) new definition of bypass valve has been introduced (3.8.104);
h) the evaluation of motor-compressors using a motor-compressor control system has been
clarified (6.101, 6.103, 6.104, 19.1);
i) modification of electric strength test has been added (16.2);
j) reference to the fatigue test has been deleted (Clause 18);
k) compliance for pressure tests has been updated (22.7, Annex EE);
l) reference for the motorette has been transferred from Annex BB to the new Annex FF;
m) annex for insulation materials and parts has been updated and tie cord relaxation has been
removed (Annex CC);
n) new annex for motorette or coilette has been introduced (Annex FF).
The text of this International Standard is based on the following documents:
Draft Report on voting
61C/924/FDIS 61C/926/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/publications.
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 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.

– 6 – IEC 60335-2-34:2024 © IEC 2024
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.
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 document indicates
that it contains colours which are considered to be useful for the correct understanding
of its contents. Users should therefore print this document using a colour printer.

IEC 60335-2-34:2024 © IEC 2024 – 7 –
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 can be examined and tested according to the intent of the
requirements and, if found to be substantially equivalent, can 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

– 8 – IEC 60335-2-34:2024 © IEC 2024
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 can 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.
Operational tests can also be conducted on the motor-compressor separately in certain
circumstances. The specification for this type testing is provided in Annex AA. However, it is
possible that the tests of the existing standards relevant to the given kind of application, such
as IEC 60335-2-24 and IEC 60335-2-40, will be conducted on the end product and used as the
final determination of acceptability.

IEC 60335-2-34:2024 © IEC 2024 – 9 –
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 can 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 multi-phase, 600 V direct-current
(DC) 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);
– refrigerating equipment for measurement, control, and laboratory use (IEC 61010-2-011);
– professional ice-cream makers (IEC 60335-2-118);
– professional 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, it will not be necessary for the tests for the motor-
compressor specified in the particular appliance standard 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 end product.
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 60335-2-34:2024 © IEC 2024
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;
– 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), 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.
This standard does not apply to
– motor-compressors designed exclusively for industrial purposes.
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 817:2014/AMD2:2021
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
maximum allowable pressure
PS
maximum pressure for which motor-compressor is designed, as specified by the manufacturer,
taking into account expected end-use appliance conditions
_____________
A consolidated version of this document exists, comprising IEC 60851-5:2008, IEC 60851-5:2008/AMD1:2011
and IEC 60851-5:2008/AMD2:2019.

IEC 60335-2-34:2024 © IEC 2024 – 11 –
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 low back pressure (SC R-744LBP): denotes a maximum evaporation temperature of –15 °C;
– transcritical low back pressure (TC R-744LBP): denotes a maximum evaporation temperature of –15 °C;
– transcritical medium back pressure (TC R-744MBP): denotes a maximum evaporation temperature of 0°C;
– transcritical high back pressure (TC R-744HBP): denotes a maximum evaporation temperature of +15°C;
– maximum load condition (MLC) declared by the manufacturer.
3.1.103
maximum load condition
MLC
maximum application conditions at which the motor-compressor is allowed to operate
as declared by the manufacturer
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 can be permanently sealed, such as by welding or brazing (hermetic motor-
compressor) or can 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 can 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
Note 1 to entry: All connecting tubes to the motor-compressor (e.g.: process tube, discharge tube, suction tube)
are part of the housing.
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
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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: Motor-compressor protection system 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: Motor-compressor protection system 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
3.8.102
motorette
insulation system model made to embody all of the elements of a random wound insulation
system
Note 1 to entry: Random wound is used to describe a motor winding in which round insulated conductors occupy
random positions in a slot.
3.8.103
coilette
modified arrangement of a motorette resembling a partially assembled motor
Note 1 to entry: Coilette is a motorette without the frame.

IEC 60335-2-34:2024 © IEC 2024 – 13 –
3.8.104
bypass valve
device that relieves high-side pressure into the low-side at a predetermined pressure differential
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
can also be provided or are needed.
For the test of 22.7, two samples of the empty housing are required.
For the test of normative Annex EE, three samples of the empty housing are required.
5.6 Addition:
Variable speed motor-compressors shall run at maximum speed unless specified differently
in declared maximum load conditions (MLC).
5.7 Replacement:
Tests are carried out in an ambient temperature of 20 °C ± 5 °C unless specified differently in
the standard.
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, one or more samples (running and locked rotor) shall be provided,
and if necessary, shall be charged with oil and vapour refrigerant. The sample shall be provided
with the motor-compressor protection system, starting relay, start capacitor, run capacitor
and control system, if any, as specified 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;
– 14 – IEC 60335-2-34:2024 © IEC 2024
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 normative Annex AA;
– whether a supply cord can be connected directly to terminals on the motor-compressor.
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 will not necessarily 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 normative Annex AA and Clause 19. If multiple protective
devices are declared, each shall be tested independently.
6 Classification
This clause of Part 1 is applicable, except as follows.
6.101 Motor-compressors are classified as being tested with or without normative Annex AA.
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 motor-compressor
protection system or not being protected by motor-compressor protection system.
This does not preclude the motor-compressor protection system being provided in the end
product, in which case many of the tests of this standard shall be conducted on the end product.

IEC 60335-2-34:2024 © IEC 2024 – 15 –
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 or 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.
6.106 The manufacturer shall declare any substitute material being used in normative
Annex BB or normative Annex CC or normative Annex FF as previously tested.
Compliance is checked by inspection.
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
Warning; Risk of fire/Flammable material
W021 (2011-05)]
7.7 Not applicable.
7.12 Not applicable, except 7.12.1, which is applicable.
Addition:
– When the maximum load condition (MLC) is declared by the manufacturer, the operating
conditions shall be included in the manufacturer’s instructions for the refrigerants used.
NOTE 1 Examples of operating conditions are:
– maximum evaporation temperature;
– maximum condensation temperature;
– maximum discharge pressure for transcritical system;
– maximum return gas temperature;
– maximum ambient temperature;
– maximum speed of inverter if applicable.

– 16 – IEC 60335-2-34:2024 © IEC 2024
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.
7.102 The maximum allowable pressure (PS) for low and high side shall be indicated in the
manufacturer’s instruction.
8 Protection against access to live parts
This clause of Part 1 is ap
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