IEC 60947-7-1:2025

IEC 60947-7-1 ®
Edition 4.0 2025-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Low-voltage switchgear and controlgear –
Part 7-1: Ancillary equipment – Terminal blocks for copper conductors

Appareillage à basse tension –
Partie 7-1: Matériels accessoires – Blocs de jonction pour conducteurs en cuivre
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IEC 60947-7-1 ®
Edition 4.0 2025-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Low-voltage switchgear and controlgear –

Part 7-1: Ancillary equipment – Terminal blocks for copper conductors

Appareillage à basse tension –

Partie 7-1: Matériels accessoires – Blocs de jonction pour conducteurs en

cuivre
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.130.20  ISBN 978-2-8327-0335-9

– 2 – IEC 60947-7-1:2025 © IEC 2025
CONTENTS
FOREWORD . 5
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 8
4 Classification . 8
5 Characteristics . 9
5.1 Summary of characteristics . 9
5.2 Type of terminal block . 9
5.3 Rated and limiting values . 9
5.3.1 Rated voltages . 9
5.3.2 Short-time withstand current . 9
5.3.3 Standard cross-sections . 9
5.3.4 Rated cross-section . 9
5.3.5 Rated connecting capacity . 9
6 Product information . 10
6.1 Marking . 10
6.1.1 Manufacturer or trade mark . 10
6.1.2 Type reference . 10
6.2 Additional information . 10
7 Normal service, mounting and transport conditions . 11
8 Constructional and performance requirements . 11
8.1 Constructional requirements . 11
8.1.1 Clamping units . 11
8.1.2 Mounting . 11
8.1.3 Clearances and creepage distances . 11
8.1.4 Terminal block identification and marking . 12
8.1.5 Resistance to abnormal heat and fire . 12
8.1.6 Rated cross-section and rated connecting capacity . 12
8.2 Performance requirements . 12
8.2.1 Temperature-rise . 12
8.2.2 Dielectric properties . 12
8.2.3 Short-time withstand current . 12
8.2.4 Voltage drop . 12
8.2.5 Electrical performance after ageing (for screwless-type terminal blocks
only) . 13
8.2.6 Contact pressure via insulating material (CoPI) . 13
8.3 Electromagnetic compatibility . 13
9 Tests . 13
9.1 Kinds of test . 13
9.2 General . 13
9.3 Verification of mechanical characteristics . 14
9.3.1 General . 14
9.3.2 Attachment of the terminal block on its support . 14
9.3.3 Mechanical properties of clamping units . 15
9.4 Verification of electrical characteristics . 17
9.4.1 General . 17

9.4.2 Verification of clearances and creepage distances . 17
9.4.3 Dielectric tests . 17
9.4.4 Verification of the voltage drop . 18
9.4.5 Temperature-rise test . 19
9.4.6 Short-time withstand current test . 20
9.4.7 Ageing test (for screwless-type terminal blocks only) . 20
9.4.8 Contact pressure via insulating material (CoPI) test . 21
9.5 Verification of thermal characteristics. 22
9.6 Verification of EMC characteristics . 23
9.6.1 General . 23
9.6.2 Immunity . 23
9.6.3 Emission . 24
Annex A (informative) Main characteristics for terminal blocks . 32
A.1 General . 32
A.2 Properties of terminal blocks . 32
A.3 Properties of test disconnect terminal blocks . 32
Annex B (informative) Items subject to extended tests for special product applications . 33
Annex C (informative) Examples for verifying the connecting capacity based on tests
with both metric and AWG/kcmil conductors . 34
C.1 General . 34
C.2 Example 1: Testing with metric conductors . 34
C.3 Example 2: Testing with metric and AWG/kcmil conductors . 34
C.4 Example 3: Testing with AWG/kcmil conductors . 34
Annex D (normative) Requirements for test disconnect terminal blocks . 35
D.1 Scope . 35
D.2 Normative references . 35
D.3 Terms and definitions . 35
D.4 Classification . 35
D.5 Characteristics . 35
D.5.1 Summary of characteristics . 35
D.5.2 Type of test disconnect terminal block . 36
D.5.3 Rated and limiting values . 36
D.6 Product information . 36
D.6.1 Marking . 36
D.6.2 Additional information . 37
D.7 Normal service, mounting and transport conditions . 37
D.8 Constructional and performance requirements . 37
D.8.1 Constructional requirements . 37
D.8.2 Performance requirements . 38
D.8.3 Service life . 39
D.8.4 Electromagnetic compatibility . 39
D.9 Tests . 40
D.9.1 Kinds of test . 40
D.9.2 General . 40
D.9.3 Verification of mechanical characteristics . 40
D.9.4 Verification of electrical characteristics . 40
D.9.5 Verification of thermal characteristics . 44
D.9.6 Service life . 44
D.9.7 Verification of EMC characteristics . 44

– 4 – IEC 60947-7-1:2025 © IEC 2025
Annex E (informative) Electrical and mechanical parameters for terminal blocks used
with conductors of rated cross-section above 300 mm /600 kcmil . 47
Bibliography . 49

Figure 1 – Arrangement for test according to 9.3.2. 15
Figure 2 – Arrangement for tests according to 9.4.5 and 9.4.7, and for the verification
of voltage drop . 19
Figure 3 – Arrangement for test according to 9.5 . 23
Figure 4 – Point of test flame contact (view from the layer place below the terminal
block). 23
Figure D.1 – Test requirements according to D.9.4.4 for verification of the voltage drop . 42

Table 1 – Test current for standard cross-sections and minimal requirement of rated
connecting capacity (see 9.3.3.4 and 9.4.4, 9.4.5) . 24
Table 2 – Attachment test parameter, test values for flexion and pull-out and
relationship between conductor cross-section and diameter for standard cross-section
(see 9.3.2, 9.3.3.2 and 9.3.3.3) . 27
Table B.1 – Additional items subject to agreement between manufacturer and user . 33
Table D.1 – Operating cycles . 44
Table D.2 – Short-time withstand current and corresponding wire sizes . 45
Table E.1 – Electrical parameters for terminal blocks used with conductors of rated
cross-section above 300 mm /600 kcmil . 47
Table E.2 – Mechanical parameters for terminal blocks used with conductors of rated
cross-section above 300 mm /600 kcmil . 48

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
LOW-VOLTAGE SWITCHGEAR AND CONTROLGEAR –

Part 7-1: Ancillary equipment –
Terminal blocks for copper conductors

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
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) IEC draws attention to the possibility that the implementation of this document may involve the use of (a)
patent(s). IEC takes no position concerning the evidence, validity or applicability of any claimed patent rights in
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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 60947-7-1 has been prepared by subcommittee 121A: Low-voltage switchgear and
controlgear, of IEC technical committee 121: Switchgear and controlgear and their assemblies
for low-voltage. It is an International Standard.
This fourth edition cancels and replaces the third edition published in 2009. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) Scope extension for smaller conductor cross-sections;
b) Implementation of a contact pressure via insulation material (CoPI) test;
c) Introduction of new informative Annex E for larger cross-sections;

– 6 – IEC 60947-7-1:2025 © IEC 2025
d) Reorganisation of all tables merged into two tables for electrical and mechanical values;
e) Implementation of AWG-sizes conductor types as an equivalent type of metric conductor
with examples in Annex C;
f) Reorganisation of Annex D test disconnect terminal blocks to enhance readability;
g) Introduction of new informative Annex A for main characteristics of terminal blocks.
This document shall be read in conjunction with IEC 60947-1:2020. The provisions of the
general rules dealt with in IEC 60947-1:2020 are applicable to this document, where specifically
called for. Clauses and subclauses, tables, figures and annexes thus applicable are identified
by reference to IEC 60947-1:2020, e.g. 1.2 of IEC 60947-1:2020, Table 4 of IEC 60947-1:2020
or Annex A of IEC 60947-1:2020.
The text of this International Standard is based on the following documents:
Draft Report on voting
121A/646/FDIS 121A/674/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.
A list of all parts in the IEC 60947 series, published under the general title Low-voltage
switchgear and controlgear, can be found on the IEC website.
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.
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.
LOW-VOLTAGE SWITCHGEAR AND CONTROLGEAR –

Part 7-1: Ancillary equipment –
Terminal blocks for copper conductors

1 Scope
This part of IEC 60947 specifies requirements for terminal blocks and test disconnect terminal
blocks according to Annex D with screw-type or screw-less-type clamping units primarily
intended for industrial or similar use and to be fixed to a support to provide electrical and
mechanical connection between copper conductors. It applies to terminal blocks intended to
connect round copper conductors, with or without special preparation, having a cross-section
2 2
between 0,05 mm /30 AWG and 300 mm /600 kcmil, intended to be used in circuits of a rated
voltage not exceeding 1 000 V AC up to 1 000 Hz or 1 500 V DC. The tests on terminal blocks
are made with AC or DC supply as required in relevant clauses of this document.
NOTE 1 This document is not intended for connecting devices for household purposes according to IEC 60998-1.
NOTE 2 AWG is the abbreviation of "American Wire Gage" (Gage (US) = Gauge (UK));
kcmil = 1 000 cmil;
1 cmil = 1 circular mil = surface area of a circle having a diameter of 1 mil;
1 mil = 1/1 000 inch.
NOTE 3 This document can be used as a guide in conjunction with an additional product risk assessment for:
– terminal blocks requiring the fixing of special devices to the conductors, for example quick connect terminations
or wrapped connection, etc.;
– terminal blocks providing wire-binding screw (see IEC 60947-1:2020, Figure D.2), stud and nut terminations (see
IEC 60947-1:2020, Figures D.4 and D.5), lug terminations (see IEC 60947-1:2020, Figure D.6) and terminal
blocks providing direct contact to the conductors by means of edges or points penetrating the insulation, for
example insulation displacement connection (IDC) (see IEC 60352-4:2020, Figure 2), etc.;
– special types of terminal blocks, for example with diodes or varistors or similar component holders, etc.;
– terminal blocks with capability to connect conductors with cross sections larger than 300 mm /600 kcmil, see
Annex E.
Where applicable in this document, the term "clamping unit" has been used instead of the term
"terminal". This is taken into account in case of reference to IEC 60947-1:2020.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their content
constitutes requirements of this document. For dated references, only the edition cited applies.
For undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60068-2-1:2007, Environmental testing – Part 2-1: Tests – Test A: Cold
IEC 60068-2-2:2007, Environmental testing – Part 2-2: Tests – Test B: Dry heat
IEC 60695-11-5:2016, Fire hazard testing – Part 11-5: Test flames – Needle-flame test method
– Apparatus, confirmatory test arrangement and guidance
IEC 60947-1:2020, Low-voltage switchgear and controlgear – Part 1: General rules

– 8 – IEC 60947-7-1:2025 © IEC 2025
ISO 4046-4:2016, Paper, board, pulps and related terms – Vocabulary – Part 4: Paper and
board grades and covered products
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60947-1:2020 and
the following apply.
ISO and IEC maintain terminology databases for use in standardization at the following
addresses:
• IEC Electropedia: available at https://www.electropedia.org/
• ISO Online browsing platform: available at https://www.iso.org/obp
3.1
terminal block
insulating part carrying one or more mutually insulated terminal assemblies and intended to be
fixed to a support
3.2
rated cross-section
value of the maximum cross-section of all connectable types of conductors, rigid (solid and
stranded) and flexible, stated by the manufacturer, and to which certain thermal, mechanical
and electrical requirements are referred
3.3
rated connecting capacity
range of cross-section and, if applicable, the number of connectable conductors, for which the
terminal block is designed
3.4
terminal assembly
two or more clamping units fixed to the same conductive part
3.5
contact pressure via insulating material
CoPI
contact force of a clamping unit where contact pressure is transmitted
through insulating material
4 Classification
Distinction is made between various types of terminal blocks as follows:
– method of fixing the terminal block to the support;
– number of poles;
– type of clamping units: screw-type clamping units or screwless-type clamping units (see
3.5.25 of IEC 60947-1:2020);
– ability to receive prepared conductors (see 3.5.28 of IEC 60947-1:2020);
– terminal assemblies with identical or dissimilar clamping units;
– number of clamping units on each terminal assembly;
– service conditions;
– ability to receive different types of conductors, e.g. solid, rigid stranded or flexible
conductors.
5 Characteristics
5.1 Summary of characteristics
The characteristics of a terminal block are as follows:
– type of terminal block (see 5.2);
– rated and limiting values (see 5.3).
5.2 Type of terminal block
The following shall be stated:
– type of clamping units (e.g. screw-type, screwless-type);
– number of clamping units.
5.3 Rated and limiting values
5.3.1 Rated voltages
Subclauses 5.3.1.2 and 5.3.1.3 of IEC 60947-1:2020 apply.
5.3.2 Short-time withstand current
A specified RMS value of current which a terminal block shall be able to withstand during a
specified short-time under prescribed conditions of use and behaviour (see 8.2.3 and 9.4.6).
5.3.3 Standard cross-sections
The standard values of cross-sections of round copper conductors to be used are contained in
Table 1.
5.3.4 Rated cross-section
The rated cross-section shall be selected from the standard cross-sections given in Table 1.
5.3.5 Rated connecting capacity
For terminal blocks with a rated cross-section of 35 mm /2 AWG or less, the minimal
requirement of rated connecting capacity specified in Table 1 applies. A rated connecting
capacity wider than the rated connecting capacity specified in Table 1 is to be declared, if
applicable.
For rated cross-sections above 35 mm /2 AWG, the manufacturer shall state the maximum and
minimum cross sections conductors that can be connected. Several connecting capacities can
be defined according to the type of conductors, rigid (solid or stranded) or flexible, while
remaining consistent with the same rated cross-section.
The manufacturer shall also state the number of conductors that can be connected
simultaneously to each clamping unit and any necessary preparation at the end of the
conductor.
– 10 – IEC 60947-7-1:2025 © IEC 2025
6 Product information
6.1 Marking
6.1.1 Manufacturer or trade mark
All terminal blocks shall be marked in a durable and legible manner with the name of the
manufacturer or a trade mark by which the manufacturer can be readily identified.
6.1.2 Type reference
The type-reference permitting the identification of terminal blocks shall be provided in order to
obtain relevant information from the manufacturer or his product documentation (e.g.
machine-readable code with reference to internet, electronic catalogues, web-link on the
package unit or product inserts, etc.).
The type-reference shall be marked on the terminal block or, if the dimensions of the terminal
block do not permit durable and legible marking, on the smallest package unit or product inserts.
6.2 Additional information
The following information shall be stated in the product documentation (e.g. machine-readable
code with reference to internet, electronic catalogues, web-link on the package unit or product
inserts, etc.):
a) the rated cross-section;
b) the rated connecting capacity, if wider than in Table 1;
c) the rated insulation voltage (U );
i
d) the rated impulse withstand voltage (U ), when determined;
imp
e) service conditions, if different from those of Clause 7;
f) conventional free air thermal current (I ), if applicable;
th
g) the following information for non-universal terminal blocks, depending on the classification,
shall be used, if applicable:
– for clamping units declared for solid conductors "solid" or the abbreviations "s" or "sol";
– for clamping units declared for rigid stranded conductors "rigid stranded" or the
abbreviation "r";
– for clamping units declared for flexible conductors "flexible" or the abbreviation "f";
h) special preparation of the end of the conductor, if applicable;
i) the number of conductors simultaneously connectable, if different from one;
j) the manufacturer`s declared tightening torque of screw-type clamping units, either from
Table 4 of IEC 60947-1:2020 or higher, if applicable;
k) installation instructions;
l) safety instructions.
NOTE 1 In some countries tightening torque values lower than those as listed in Table 4 of IEC 60947-1:2020 are
allowed according to their national product standards: United States of America and Canada.
NOTE 2 Material declarations according to IEC TS 63058 or equivalent can be provided. IEC TS 63058 provides
methods for assessing the environmental impact of switchgear and controlgear, guidance on environmentally
conscious design and on information required for end-of-life treatments.
NOTE 3 Properties listed in IEC 62683 (CDD) can be found in Annex A.

7 Normal service, mounting and transport conditions
Clause 7 of IEC 60947-1:2020 applies.
Terminal blocks are electrical components, which are typically installed in enclosures providing
a specified degree of protection of equipment against certain external influences and a specified
degree of protection against approach to or contact with hazardous live parts and hazardous
mechanical part.
NOTE No IP degree listing for terminal blocks is required, but possible.
8 Constructional and performance requirements
8.1 Constructional requirements
8.1.1 Clamping units
Subclause 8.1.8.1 of IEC 60947-1:2020 applies with the following modifications.
The clamping units shall allow the conductors to be connected by means ensuring that a reliable
mechanical linkage and electrical contact is properly maintained.
Screw-type clamping units are not suitable for the connection of flexible conductors with tin
soldered ends.
The clamping units shall be able to withstand the force that can be applied through the
connected conductors.
Compliance is checked by inspection and by the tests of 9.3.3.1, 9.3.3.2 and 9.3.3.3.
If contact pressure of the clamping unit is transmitted through insulating material other than
ceramic or pure mica, the test described in 9.4.8 (contact pressure via insulating material (CoPI)
test) shall be performed to prove that there is sufficient resiliency in the metallic parts to
compensate for any possible shrinkage of the insulation material.
8.1.2 Mounting
Terminal blocks shall be provided with means that allow them to be securely attached to a rail
or a mounting surface.
Tests shall be made in accordance with 9.3.2.
NOTE Information on mounting on rails can be found in IEC 60715.
8.1.3 Clearances and creepage distances
For terminal blocks for which the manufacturer has stated values of rated impulse withstand
voltage (U ) and rated insulation voltage (U ), minimum values of clearances and creepage
imp i
distances are given in Table 13 and Table 15 of IEC 60947-1:2020.
For terminal blocks for which the manufacturer has not declared a value of rated impulse
withstand voltage (U ), guidance for minimum values is given in Annex H of
imp
IEC 60947-1:2020.
Electrical requirements are given in 8.2.2.

– 12 – IEC 60947-7-1:2025 © IEC 2025
8.1.4 Terminal block identification and marking
Subclause 8.1.8.4 of IEC 60947-1:2020 applies with the following addition.
A terminal block shall have provision, or at least space, for identification marks or numbers for
each clamping unit or terminal assembly related to the circuit of which it forms a part.
For the identification of the terminal blocks the colour combination green-yellow is not allowed.
NOTE Such provision might consist of separate marking items, such as marking tags, identification labels, etc.
8.1.5 Resistance to abnormal heat and fire
The insulation material of the terminal block shall not be adversely affected by abnormal heat
and fire.
Compliance is checked by the needle flame test according to IEC 60695-11-5:2016 as specified
in 9.5.
8.1.6 Rated cross-section and rated connecting capacity
Terminal blocks shall be so designed that conductors of the rated cross-section and the rated
connecting capacity, if applicable, can be accepted.
The verification of the rated connecting capacity and rated cross-section is checked by the test
according in 9.3.3.4.
NOTE The verification of the rated cross-section can be performed by the special test according to 9.3.3.5.
8.2 Performance requirements
8.2.1 Temperature-rise
The temperature-rise of any part of the centrally located terminal block shall not exceed 45 K,
see Figure 2.
8.2.2 Dielectric properties
If the manufacturer has declared a value of the rated impulse withstand voltage (U ) (see
imp
5.3.1.3 of IEC 60947-1:2020), the requirements of 8.2.3.1 except item c) and 8.2.3.2 of
IEC 60947-1:2020 apply. If applicable, the impulse withstand voltage test shall be carried out
in accordance with 9.4.3 a) of this document. For the verification of solid insulation, the
requirements of 8.2.3.1 except item c) of IEC 60947-1:2020 apply. The power-frequency
withstand voltage test shall be carried out in accordance with 9.4.3 b).
The verification of sufficient clearances and creepage distances shall be made in accordance
with 9.4.2.
8.2.3 Short-time withstand current
A terminal block shall be capable of withstanding for 1 s the short-time withstand current which
corresponds to 120 A/mm of its rated cross-section, in accordance with 9.4.6.
8.2.4 Voltage drop
The voltage drop on a terminal block, measured according to 9.4.4, shall not exceed the values
specified in 9.4.4 and, where applicable, in 9.4.7.

8.2.5 Electrical performance after ageing (for screwless-type terminal blocks only)
Screwless-type terminal blocks without contact pressure via insulating material (CoPI) shall be
capable of withstanding the ageing test comprising 192 temperature cycles in accordance with
9.4.7.
Screwless-type terminal blocks with contact pressure via ceramic or pure mica shall be capable
of withstanding the ageing test comprising 192 temperature cycles in accordance with 9.4.7.
Screwless-type terminal blocks with contact pressure via insulating material (CoPI) other than
ceramic or pure mica shall fulfil the requirements of 8.2.6.
8.2.6 Contact pressure via insulating material (CoPI)
Terminal blocks with contact pressure via insulating material (CoPI) other than ceramic or pure
mica, shall be capable of withstanding the ageing test sequence including preconditioning and
comprising 384 temperature cycles in accordance with 9.4.8.
8.3 Electromagnetic compatibility
Subclause 8.3 of IEC 60947-1:2020 applies.
Compliance is checked by the tests described in 9.6.
9 Tests
9.1 Kinds of test
Subclause 9.1.1 of IEC 60947-1:2020 applies with the following addition.
No routine tests are specified. The verification of the rated cross-section according to 9.3.3.5
is a special test. All other tests are type tests.
9.2 General
Unless otherwise specified, terminal blocks are tested in new and in clean condition, and
installed as for normal use (see 7.3 of IEC 60947-1:2020) at an ambient temperature of
(20 ± 5) °C.
NOTE 1 "Normal use" means that five terminal blocks are mounted on their support, the remaining open side closed
by an end plate and fixed by end brackets, if applicable.
NOTE 2 Other test conditions can be found in Annex B.
The tests are carried out in the same order in which the subclauses describe them.
Each test is made on new separate specimens.
The tests of 9.3.3.2 and 9.3.3.3 are made on the same specimens.
The surface of the conductors shall be free of contamination and corrosion which degrades
performance.
Care shall be taken when stripping conductors to avoid cutting, nicking, scraping or otherwise
damaging the conductors.
In case where the manufacturer has stated that special preparation of the end of the conductor
is necessary, the test report shall indicate the method of preparation used.

– 14 – IEC 60947-7-1:2025 © IEC 2025
The tests are carried out with the type of conductor (rigid or flexible) from Table 1 or as stated
by the manufacturer. Testing covers conductor sizes that are within the cross-sectional area
envelope of the sizes tested, as determined by the cross-section of the conductor. See Table 1
or Table 2 for conductor area, in mm and AWG/kcmil, for conductor stranding, and for
conductor diameters, of both metric and AWG/kcmil conductor.
NOTE 3 Examples for testing with both metric and AWG/kcmil conductors, see Annex C.
If one of the terminal blocks does not withstand one of the tests, this test shall be repeated on
a second set of terminal blocks, all of which shall then comply with the repeated test. If this test
is a part of a test sequence, the complete test sequence shall be repeated.
The tests on terminal blocks shall be made with AC or DC supply as required in relevant clauses
of this document.
9.3 Verification of mechanical characteristics
9.3.1 General
The verification of mechanical characteristics includes the following tests:
– attachment of the terminal block on its support (see 9.3.2);
– mechanical strength of clamping units (see 9.3.3.1);
– attachment of the conductors to the clamping units (see 9.3.3.2 and 9.3.3.3)
...