IEC 60670-24:2024

IEC 60670-24 ®
Edition 3.0 2024-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Boxes and enclosures for electrical accessories for household and similar fixed
electrical installations –
Part 24: Particular requirements for enclosures for housing protective devices
and other power dissipating electrical equipment

Boîtes et enveloppes pour appareillage électrique pour installations électriques
fixes pour usages domestiques et analogues –
Partie 24: Exigences particulières pour les enveloppes pour dispositifs de
protection et autres matériels électriques ayant une puissance dissipée
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IEC 60670-24 ®
Edition 3.0 2024-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Boxes and enclosures for electrical accessories for household and similar fixed

electrical installations –
Part 24: Particular requirements for enclosures for housing protective devices

and other power dissipating electrical equipment

Boîtes et enveloppes pour appareillage électrique pour installations électriques

fixes pour usages domestiques et analogues –

Partie 24: Exigences particulières pour les enveloppes pour dispositifs de

protection et autres matériels électriques ayant une puissance dissipée

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.120.10  ISBN 978-2-8327-0052-5

– 2 – IEC 60670-24:2024 © IEC 2024
CONTENTS
FOREWORD . 4
1 Scope . 7
2 Normative references . 8
3 Terms and definitions . 8
4 General requirements . 10
5 General notes on tests . 10
6 Ratings . 10
7 Classification . 11
8 Marking . 11
9 Dimensions. 12
10 Protection against electric shock . 13
11 Provisions for earthing . 13
12 Construction . 14
13 Resistance to ageing, protection against ingress of solid foreign objects and
against harmful ingress of water . 15
14 Insulation resistance and electric strength . 15
15 Mechanical strength . 15
16 Resistance to heat . 16
17 Creepage distances, clearances and distances through sealing compound . 16
18 Resistance of insulating material to abnormal heat and to fire . 17
19 Resistance to tracking . 17
20 Resistance to corrosion . 17
21 Electromagnetic compatibility . 17
101 Verification of the maximum capability to dissipate power (P ) . 17
de
102 Verification of temperature rise . 24
Annex AA (normative) Instructions to be given by the manufacturer of the GP
enclosure to the installer on how to integrate accessories, and providing an example of
calculation . 26
Annex BB (normative) Instructions to be given by the manufacturer of the PD
enclosure to the installer on how to integrate accessories . 37
Annex CC (normative) Additional requirements for enclosures exposed to direct
sunlight . 39
Annex DD (normative) Additional requirements for enclosures to accommodate
multimedia and communication equipment . 40
Annex EE (normative) Additional requirements for enclosures for use with connected
devices or equipment . 42
Bibliography . 46

Figure 101 – Arrangement for the verification of the maximum capability to dissipate
power (P ) and for verification of temperature rise of surface type enclosures . 19
de
Figure 102 – Heating resistor for the verification of the maximum capability to dissipate
power (P ) . 20
de
Figure 103 – Position of the resistor for enclosures designed or intended to be fitted
with rail mounting modular accessories and electrical equipment . 21

Figure 104 – Position of the resistor(s) for enclosures other than those designed or
intended to be fitted with rail mounting accessories and electrical equipment . 22
Figure 105 – Position of the resistor(s) for enclosures other than those designed or
intended to be fitted with rail mounting accessories and electrical equipment and
allowing the mounting of several accessories and electrical equipment in different
positions . 23
Figure AA.1 – Diagram of the equipped GP enclosure . 31
Figure AA.2 – Diagram of the equipped GP enclosure . 34

Table 1 – Classification of boxes and enclosures . 11
Table 101 – Creepage distances, clearances and distances through sealing compound . 16
Table 102 – Diversity factor . 25
Table 103 – Temperatures of accessible surfaces . 25
Table AA.1 – Diversity factor. 27
Table AA.2 – Tests and verifications . 28
Table AA.3 – Calculation of P . 32
dp
Table AA.4 – Calculation of P . 32
au
Table AA.5 – Calculation of P . 35
dp
Table AA.6 – Calculation of P . 36
au
Table AA.7 – Calculation of P . 36
el
– 4 – IEC 60670-24:2024 © IEC 2024
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
BOXES AND ENCLOSURES FOR ELECTRICAL ACCESSORIES FOR
HOUSEHOLD AND SIMILAR FIXED ELECTRICAL INSTALLATIONS –

Part 24: Particular requirements for enclosures for housing protective
devices and other power dissipating electrical equipment

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
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any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
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 60670-24 has been prepared by subcommittee 23B: Plugs, socket-outlets and switches, of
IEC technical committee 23: Electrical accessories. It is an International Standard.
This third edition cancels and replaces the second edition published in 2011. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) revision of requirements for protection against electric shock in Clause 10;
b) addition of requirements for functional earthing in 11.101;
c) revision of the requirements for fixing of flush type and semi-flush type enclosures in 12.12;

d) revision of the requirements for resistance of insulating material to abnormal heat and to
fire in Clause 18;
e) addition of calculations to take into account the power loss of electronic devices in
Clause AA.6;
f) addition of tests and requirements for enclosures exposed to direct sunlight with the related
Annex CC;
g) addition of tests and requirements for enclosures with separate area to accommodate
multimedia-equipment with the related Annex DD;
h) addition of tests and requirements for enclosures used with connected devices or equipment
with the related Annex EE.
The text of this International Standard is based on the following documents:
Draft Report on voting
23B/1536/FDIS 23B/1554/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 in the IEC 60670 series, published under the general title Boxes and enclosures
for electrical accessories for household and similar fixed installations, can be found on the IEC
website.
This document is to be used in conjunction with IEC 60670-1:2024. It lists the changes
necessary to convert that standard into a specific standard for housing protective devices and
other power dissipating electrical equipment.
Where this document states "addition", "modification" or "replacement", the relevant
requirement, test specifications or explanatory matter in IEC 60670-1:2024 shall be adapted
accordingly.
Clauses and subclauses, notes, figures or tables which are additional to those in
IEC 60670-1:2024 are numbered starting from 101.
Additional annexes to IEC 60670-1:2024 are numbered AA, BB, etc.
In this publication the following print types are used:
• requirements proper: in roman type.
• test specifications: in italic type.
• notes: in smaller roman type.

– 6 – IEC 60670-24:2024 © IEC 2024
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.
BOXES AND ENCLOSURES FOR ELECTRICAL ACCESSORIES FOR
HOUSEHOLD AND SIMILAR FIXED ELECTRICAL INSTALLATIONS –

Part 24: Particular requirements for enclosures for housing protective
devices and other power dissipating electrical equipment

1 Scope
Replacement:
This part of IEC 60670 applies to enclosures and parts of them for housing protective devices
and other power dissipating electrical equipment intended to be used with a rated voltage not
exceeding 400 V and a total incoming load current not exceeding 125 A for household and
similar fixed electrical installations.
These enclosures are intended to be installed in locations where unskilled persons have access.
They are intended to be equipped with electrical equipment by skilled persons (installers).
These enclosures are intended to be installed where the prospective short circuit current does
not exceed 10 kA unless they are protected by current limiting protective devices with a cut-off
current not exceeding 17 kA.
Enclosures complying with this document are suitable for use at ambient temperature not
normally exceeding 40 °C, but their average temperature over a period of 24 h does not exceed
35 °C, with a lower limit of the ambient air temperature of −5 °C.
An enclosure which is an integral part of an electrical accessory and provides protection against
external influences (e.g. mechanical impacts, ingress of solid objects or of water), is covered
by the relevant standard for such an accessory.
This document does not apply to a low-voltage switchgear and controlgear assembly as defined
in the IEC 60439 series or IEC 61439 series nor to a main entrance panel which can be part of
the distribution board.
This document does not apply to surface type boxes, flush and semi-flush type boxes suitable
for the housing of accessories for household and similar use such as switches, electronic
switches, socket-outlets, which are covered by IEC 60670-1 only.
NOTE 1 Enclosures according to this document are mainly used for distribution board for housing protective devices
and other power dissipating electrical equipment and are installed at the beginning of the electrical circuit whereas
boxes according to IEC 60670-1 are installed at the end of it.
NOTE 2 A main entrance panel is a set composed of a panel or an enclosure equipped with a meter and/or the
main incoming device. Main entrance panels comply with their appropriate standards or the requirements of the local
supplier, if any.
NOTE 3 In the following country this document cannot be used in installations with a 230 V single-phase supply
rated up to 100 A that is under the control of ordinary persons. Integration of mechanical and electrical devices into
an enclosure must be verified by compliance with IEC 61439-3 [British standard EN 61439-3]: UK.
NOTE 4 In the following country this document can only be used for GP enclosures with the instructions according
to Annex A. For the other types of enclosures the integration of mechanical and electrical devices into an enclosure
is verified by compliance with DS EN 61439-3: DK.

– 8 – IEC 60670-24:2024 © IEC 2024
2 Normative references
Addition:
IEC 60364-4-41:2005, Low-voltage electrical installations – Part 4-41: Protection for safety –
Protection against electric shock
IEC 60364-4-41:2005/AMD1:2017
IEC 60364-5-54:2011, Low-voltage electrical installations – Part 5-54: Selection and erection
of electrical equipment – Earthing arrangements and protective conductors
IEC 60364-5-54:2011/AMD1:2021
IEC 60664-1, Insulation coordination for equipment within low-voltage supply systems – Part 1:
Principles, requirements and tests
IEC 60898-1, Electrical accessories – Circuit-breakers for overcurrent protection for household
and similar installations – Part 1: Circuit-breakers for a.c. operation
IEC 61008-2-1, Residual current operated circuit-breakers without integral overcurrent
protection for household and similar uses (RCCB's) – Part 2-1: Applicability of the general rules
to RCCB's functionally independent of line voltage
IEC 61009-2-1, Residual current operated circuit-breakers with integral overcurrent protection
for household and similar uses (RCBO's) – Part 2-1: Applicability of the general rules to RCBO's
functionally independent of line voltage
ISO/IEC 11801-1:2017, Information technology – Generic cabling for customer premises –
Part 1: General requirements
ISO 178:2019, Plastics – Determination of flexural properties
ISO 179-1:2010, Plastics – Determination of Charpy impact properties – Part 1:
Non-instrumented impact test
ISO 4892-2:2013, Plastics – Methods of exposure to laboratory light sources – Part 2:
Xenon-arc lamps
ISO 4892-2:2013/AMD1:2021
3 Terms and definitions
Additions:
3.101
general purpose enclosure
GP enclosure
enclosure where integration of mechanical and electrical devices has been verified by tests
carried out by the manufacturer according to this document and where the installer has to verify
the installed equipment according to the instructions given in Annex AA
3.102
enclosure for pre-determined equipment
PD enclosure
enclosure where the capability to integrate pre-determined mechanical and electrical equipment
has been verified according to design rules and tests according to this document carried out by
the manufacturer where the installer has to verify the installed equipment following the
manufacturer's instructions according to Annex BB

3.103
manufacturer's instructions
instructions in accordance with Annex AA and Annex BB leading to a configuration of the
enclosure ensuring the necessary heat dissipation
Note 1 to entry: References to standards can be given in the manufacturer's instructions.
3.104
maximum capability to dissipate power
P
de
maximum capability of the enclosure to dissipate in normal use the power losses of the installed
devices, as declared by the manufacturer
Note 1 to entry: P is expressed in watts (W).
de
3.105
rated current
I
n
maximum current assigned by the manufacturer of the enclosure which can be distributed by
the enclosure
3.106
blanking plate
component used for closing the opening, for protective devices and other power dissipating
electrical equipment, of an enclosure to provide basic insulation
3.107
enclosures with separate area to accommodate multimedia and communication
equipment
enclosure providing an area where multimedia and communication equipment are intended to
be integrated according to the additional requirements given in Annex DD
Note 1 to entry: An enclosure with separate area to accommodate multimedia and communication equipment can
be a GP or PD enclosure.
3.108
enclosure for use with connected devices or equipment
enclosure intended to accommodate protection devices, electrical equipment dissipating power
and connected devices or equipment according to the additional requirements given in
Annex EE
Note 1 to entry: An enclosure for use with connected devices or equipment can be a GP or PD enclosure.
3.109
connected devices or equipment
physical unit that can connect with other units into an interconnected infrastructure
Note 1 to entry: This physical unit can operate and communicate with the physical world through detection and
action. Such equipment or device allows the switchboard to participate in this IoT infrastructure.
3.110
rated current of the equipped GP enclosure
I
nq
rated current to be calculated as Ine multiplied by Ke
Note 1 to entry: In the absence of incoming protective and control devices, the rated current of the equipped GP
enclosure is the outgoing rated current (I ).
nu
– 10 – IEC 60670-24:2024 © IEC 2024
3.111
incoming rated current
I
ne
rated current or sum of the rated currents of all incoming protective and control devices,
expected to be used at the same time
3.112
outgoing rated current
I
nu
sum of the rated currents of all outgoing protective and control devices, expected to be used at
the same time
3.113
utilisation factor
K
e
ratio of the actual current flowing through any main incoming protective device inside the
enclosure to the rated current of this device
Note 1 to entry: The utilisation factor for incoming circuits is assumed to be 0,85.
3.114
diversity factor
K
ratio, calculated by the installer, of the rated current of the equipped GP enclosure (I ) to the
nq
outgoing rated current (I )
nu
4 General requirements
Clause 4 of IEC 60670-1:2024 is applicable.
5 General notes on tests
Clause 5 of IEC 60670-1:2024 is applicable.
6 Ratings
Replacement:
Rated values are defined as given in Annex AA and Annex BB.

7 Classification
Clause 7 of IEC 60670-1:2024 is applicable with the following modifications:
Table 1 – Classification of boxes and enclosures
Classification criteria 7.2.2.2, 7.2.2.3, 7.8.1 and 7.9 do not apply.
Addition:
7.101 Enclosure 7.101.1 GP enclosure
7.101.2 PD enclosure
NOTE 101 In the following countries only enclosures classified according to 7.101.2 can be used: BE, DE, FR
and GR.
NOTE 102 In the following country only enclosures according to 7.101.1 can be used: DK.

8 Marking
Clause 8 of IEC 60670-1:2024 is applicable with the following modifications:
Replacement:
8.1 General
Enclosures shall be marked with
a) the name, trade mark or identification mark of the manufacturer or the responsible vendor;
b) IP code against ingress of solid foreign objects and against access to hazardous parts if
higher than IP3X and/or if IP code against harmful ingress of water is higher than IPX0.
The IP code, if applicable, shall be marked on the outside of the enclosure so as to be easily
discernible when the enclosure is mounted and wired as for normal use. The visibility of the
marking is also possible after opening the door or the lid if a minimum degree of IP20 is
maintained after opening;
c) the symbol for class II protection, if applicable (IEC 60417-5172 (2003-02)) ;
d) type designation, reference number or catalogue number;
e) letter N for terminals intended exclusively for the neutral conductor, if any;
f) symbol according to IEC 60417-5019 (2006-08) for earthing terminals for the
connection of the protective conductor, if any, and/or symbol according to
IEC 60417-5018 (2011-07) for functional earthing terminal for the connection of the
functional earthing, if any.
Markings of neutral terminals and earthing terminals shall not be placed on screws, or any other
easily removable parts.
NOTE 1 Easily removable parts are those parts which can be removed during the normal installation of the
enclosure.
– 12 – IEC 60670-24:2024 © IEC 2024
The following information shall be marked on enclosures or provided by the manufacturer on
the smallest package unit or in the manufacturer's instructions, which are not required to be
provided with the product:
g) rated voltage;
NOTE 2 For three-phase systems, the combined voltage values can be considered e.g. 230/400 V.
h) rated current as declared by the manufacturer for enclosures classified according to 7.101.2;
i) reference number of this document i.e. IEC 60670-24;
j) information for parts of enclosures intended to withstand +90 °C during the casting process
of concrete into shuttering according to classification 7.2.1.3;
k) for enclosures classified according to 7.3.7 (without inlets), the necessary information
concerning the openings that can be made during installation;
l) for enclosures classified according to 7.101.1, the maximum capability to dissipate power
(P );
de
In the case of an enclosure designed with ventilation openings that can be closed, for example
with an accessory, the maximum capability to dissipate power (P ) shall be declared by the
de
manufacturer, for both closed and open positions.
m) for enclosures classified according to 7.2.2, their usability or not for installation in hollow
walls, hollow ceilings, hollow floors or furniture;
n) the corresponding dimension sheet, if any;
p) for enclosures classified according to
• 7.101.1 the marking "GP";
• 7.101.2 the marking "PD";
q) IK-code if declared.
Addition:
8.101 Required information for instruction sheet and/or documentation
The manufacturer shall:
– provide appropriate instructions regarding the means (for instance glands, grommets,
barriers, etc.) to be used to obtain the intended degree of protection;
– give information to the installer concerning the verification of the electrical continuity of the
protective circuit (see Clause 11);
– give the installer the necessary instructions:
• for enclosures classified according to 7.101.1, the manufacturer shall include in the
documentation the necessary instructions for installation and how to integrate
accessories as given in Annex AA;
• for enclosures classified according to 7.101.2, the manufacturer shall include in the
documentation the necessary instructions for installation according to the appropriate
mounting environment as given in Annex BB.
9 Dimensions
Clause 9 of IEC 60670-1:2024 is applicable.

10 Protection against electric shock
Clause 10 of IEC 60670-1:2024 is replaced by following:
Enclosures shall have a degree of protection of at least IPXXC according to IEC 60529, when
mounted and installed as for normal use, according to the manufacturer's instruction.
Enclosures are tested completed with the necessary means (such as grommets, etc.) indicated
in the manufacturer's instructions and the window opening(s), if any, completely filled up with
blank inserts delivered by the manufacturer and/or samples of products as declared by the
manufacturer.
If doors or covers of the enclosure can be opened without the use of a key or tool, they shall
be left open during the test.
Compliance is checked by the following tests.
Tests shall be carried out on parts which are accessible after installation.
The test shall be carried out in accordance with IEC 60529 where probe C of IEC 61032:1997
is applied to all places including knock-outs except membranes or the like, where yielding of
insulating material could impair the safety, with a force of 3 N.
In addition, enclosures having class II protection, when mounted and installed as for normal
use, shall:
a) cover live parts of the installed equipment with insulation material, and
b) at no point be pierced by conducting parts in such a manner that there is a possibility of a
fault voltage being brought out of the enclosure, and
c) not have conductive parts, such as plates, cover-plates or frames connected to the
protective circuit.
Compliance is checked by inspection.
11 Provisions for earthing
Clause 11 of IEC 60670-1:2024 is applicable with the following modifications:
Subclauses 11.1 to 11.3 are not applicable for enclosures with class II protection.
Add the following subclauses:
11.101 The electrical continuity of the protective circuit, if any, shall be checked.
Except for enclosures having class II protection, all exposed conductive parts of the enclosure
shall be connected separately or in groups to the protective circuit terminals.
Compliance is checked by inspection and, if necessary, by a continuity test of the protective
circuit.
A measurement shall be carried out to verify that the resistance between the terminal of the
Ω with
incoming protective conductor and the exposed conductive parts shall be less than 0,05
a current of 10 A AC or 10 A DC.

– 14 – IEC 60670-24:2024 © IEC 2024
11.102 Functional earthing
In order to ensure the robustness of the functional earthing conductor, if any, the minimum
cross-sectional area shall be at least 1,5 mm . The colour of the functional earthing conductor
shall be pink (see IEC 60445).
Compliance is checked by inspection.
12 Construction
Clause 12 of IEC 60670-1:2024 is applicable with the following modifications:
12.2 Lids, covers or cover-plates or parts of them
Replacement of the first paragraph:
Lids, covers, cover plates or parts of them, which are intended to ensure protection against
electric shock, shall be held in place effectively. They shall be removable only by the use of a
tool and/or a key.
12.2.3 Non-screw-type fixing operable without the use of a tool or a key
Addition at the end of the subclause of following sentence:
"This Subclause 12.2.3 is not applicable for blanking plates."
12.2.4 Non-screw-type fixing operable with the use of a tool or a key
Addition at the end of the subclause of following sentence:
"This Subclause 12.2.4 is not applicable for blanking plates."
12.12 Fixing of flush type and semi-flush type enclosures classified according to 7.2.2.1
Replacement:
Enclosures for hollow walls classified according to 7.2.2.1 shall provide suitable means for fixing
the enclosure to hollow walls.
Compliance is checked by the following test.
A specimen of the enclosure is mounted in a test wall in accordance with the manufacturer's
instructions. Where the manufacturer's instructions are not specific regarding the type of wall,
a sheet of plywood (10 ± 1) mm thick is used.
The enclosure is subjected to a force F of 100 N applied on the main axis of the enclosure
perpendicular to the mounting surface. Alternatively, the force can be applied by pushing
through a testing means which distributes evenly this force at the rear of the enclosure.
After this test, the specimens shall show no damage impairing their further use. and the
enclosure shall not have been displaced by more than 2 mm in comparison to the mounting
surface.
Addition:
12.101 Enclosures for hollow walls shall have provisions for retention means for cables or
means to use a separate retention device or devices.
NOTE 101 In the following country, cables are retained using fixing means applied during installation by the
installer: UK.
Compliance is checked by inspection.
12.102 Enclosures shall have enough space to allow mounting and connection of the
accessories (fully equipped) as declared by the manufacturer, in safe way.
Compliance is checked by inspection and in case of doubt by manual test using samples of
products as declared by the manufacturer and complying with the relevant standard, if any.
Any generally available conductors having the largest nominal cross-sectional area as declared
by the manufacturer shall be used.
13 Resistance to ageing, protection against ingress of solid foreign objects and
against harmful ingress of water
Clause 13 of IEC 60670-1:2024 is applicable with the following modification:
13.2 Protection against the ingress of solid foreign objects
Replacement of the first paragraph:
Enclosures shall provide a degree of protection of at least IP3X against the ingress of solid
foreign objects in accordance with their declared IP code with the lid closed, if any.
In the case of an enclosure with a door or a lid which can be opened without the use of a tool
during normal use, a minimum degree of IP20 shall be maintained after opening the door or the
lid.
NOTE In the following countries in the case of an enclosure with a door or a lid which can be opened without the
use of a tool during normal use, a minimum degree of IP30 shall be maintained after opening the door or the lid: DE,
DK.
14 Insulation resistance and electric strength
Clause 14 of IEC 60670-1:2024 is applicable.
15 Mechanical strength
Clause 15 of IEC 60670-1:2024 is applicable.
Addition:
15.101 Additional requirements for enclosure exposed to direct sunlight
If enclosures are declared to be resistant to UV radiation, the UV test and the relevant
mechanical test shall be carried out in accordance with Annex CC.
This test applies only to boxes and enclosures classified according to 7.1.1, 7.1.3 and 7.1.4.

– 16 – IEC 60670-24:2024 © IEC 2024
16 Resistance to heat
Clause 16 of IEC 60670-1:2024 is applicable.
17 Creepage distances, clearances and distances through sealing compound
Replacement:
Creepage distances, clearances and distances through sealing compound shall not be less than
the value shown in Table 101.
Table 101 – Creepage distances, clearances and distances through sealing compound
a
Alternative impulse voltage
Creepage distance, clearance and
Working voltage
distance through sealing test (1,2/50 µs) according to
compound IEC 60664-1 for clearances
V mm kV (at 2 000 m)
130 1,5 2,5
> 130 and ≤ 250 3,0 4
> 250 and ≤ 400 4,0 5
a
Depending on the effective voltage between the considered parts.
NOTE The values of clearance and creepages are given based on overvoltage category III.

Compliance is checked by measurement between the following parts:
Creepage distances and clearances:
– between live parts of different polarity;
– between live parts and
• metal covers and enclosures without insulating lining;
• the surface on which the enclosure is mounted.
Distances through sealing compound:
– between live parts covered with sealing compound and the surface on which the enclosure
is mounted.
For multi-way terminal devices and terminals without fixing means but with protection, distances
are measured between live parts and any opening which represents the closest point liable to
touch any other part when the terminal is fitted with conductors having the largest cross-
sectional area.
In cases where various terminals or connecting devices may be mounted in the enclosure, the
most unfavourable combinations shall be tested.
If the values for the clearance distances are smaller than those defined in Table 101, the
requirement shall be met by the impulse voltage withstand test in accordance with the values
in Table 101.
18 Resistance of insulating material to abnormal heat and to fire
Clause 18 of IEC 60670-1:2024 is applicable with the following modifications:
Replacement of the bullet points by the following:
– By the test made at 960 °C
• for parts of insulating material necessary to retain current-carrying parts in position.
– By the test made at 850 °C
• for parts of insulating material, necessary to retain parts of the earthing circuit in position
(with the exception of parts of insulating material needed to retain the earth terminal in
position in an enclosure), and
• for parts of insulating material of enclosures classified according to 7.2.2, with the
exception of parts protruding from the wall and internal parts of the enclosure (e.g.
separator) not necessary to retain current carrying parts in position.
– By the test made at 650 °C
• for parts of insulating mate
...