IEC 60947-1:2007/AMD2:2014

IEC 60947-1


®


Edition 5.0 2014-09



INTERNATIONAL



STANDARD



NORME
INTERNATIONALE
colour
inside
A MENDMENT 2
AM ENDEMENT 2

Low-voltage switchgear and controlgear –
Part 1: General rules

Appareillage à basse tension –
Partie 1: Règles générales

IEC 60947-1:2007-06/AMD2:2014-09(en-fr)

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IEC 60947-1



®



Edition 5.0 2014-09







INTERNATIONAL





STANDARD







NORME



INTERNATIONALE
colour

inside



A MENDMENT 2

AM ENDEMENT 2





Low-voltage switchgear and controlgear –

Part 1: General rules




Appareillage à basse tension –

Partie 1: Règles générales

















INTERNATIONAL

ELECTROTECHNICAL

COMMISSION


COMMISSION

ELECTROTECHNIQUE

PRICE CODE
INTERNATIONALE

CODE PRIX XA


ICS 29.130.20 ISBN 978-2-8322-1798-6



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® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

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– 2 – IEC 60947-1:2007/AMD2:2014

© IEC 2014


FOREWORD


This amendment has been prepared by subcommittee 17B: Low-voltage switchgear and

controlgear, of IEC technical committee 17: Switchgear and controlgear.


The text of this amendment is based on the following documents:


FDIS Report on voting

121A/15/FDIS 121A/21/RVD



Full information on the voting for the approval of this amendment can be found in the report
on voting indicated in the above table.
The committee has decided that the contents of this amendment and the base publication will
remain unchanged until the stability date indicated on the IEC web site under
"http://webstore.iec.ch" in the data related to the specific publication. At this date, the
publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.

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

_____________
1.1 Scope and object
Replace the existing text of this subclause by the following new text:
This standard applies, when required by the relevant product standard, to low-voltage

switchgear and controlgear hereinafter referred to as "equipment" or "device" and intended to
be connected to circuits the rated voltage of which does not exceed 1 000 V a.c. or
1 500 V d.c.
This standard states the general rules and common safety requirements for low-voltage
switchgear and controlgear, including:
– definitions;
– characteristics;
– information supplied with the equipment;
– normal service, mounting and transport conditions;
– constructional and performance requirements;
– verification of characteristics and performance;
– environmental aspects.

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IEC 60947-1:2007/AMD2:2014 – 3 –

© IEC 2014

This standard does not apply to low-voltage switchgear and controlgear assemblies which are

dealt with in IEC 61439 series, as applicable.


1.2 Normative references


Delete the existing reference to "IEC 60439-1:1999" and its Amendment 1.


Replace the existing references by the following new references:


IEC 60664-1:2007, Insulation coordination for equipment within low-voltage systems – Part 1:

Principles, requirements and tests

IEC 61000-3-3:2013, Electromagnetic compatibility (EMC) – Part 3-3: Limits – Limitation of
voltage changes, voltage fluctuations and flicker in public low-voltage supply systems, for
equipment with rated current ≤16 A per phase and not subject to conditional connection
IEC 61000-4-2:2008, Electromagnetic compatibility (EMC) – Part 4-2: Testing and
measurement techniques – Electrostatic discharge immunity test
IEC 61000-4-4:2012, Electromagnetic compatibility (EMC) – Part 4-4: Testing and
measurement techniques – Electrical fast transient/burst immunity test
IEC 61000-4-6:2013, Electromagnetic compatibility (EMC) – Part 4-6: Testing and
measurement techniques – Immunity to conducted disturbances, induced by radio-frequency
fields
IEC 61000-4-8:2009, Electromagnetic compatibility (EMC) – Part 4-8: Testing and
measurement techniques – Power frequency magnetic field immunity test
CISPR 11:2009, Industrial, scientific and medical equipment – Radio-frequency disturbance
characteristics – Limits and methods of measurement
Amendment 1 (2010)
Add, to the existing references, the new amendments as follows:
IEC 60947-5-1:2003, Low-voltage switchgear and controlgear – Part 5-1: Control circuit
devices and switching elements – Electromechanical control circuit devices
Amendment 1 (2009)
IEC 61000-3-2:2005, Electromagnetic compatibility (EMC) – Part 3-2: Limits – Limits for
harmonic current emissions (equipment input current ≤ 16 A per phase)
Amendment 1 (2008)
Amendment 2 (2009)
IEC 61000-4-3:2006, Electromagnetic compatibility (EMC) – Part 4-3: Testing and
measurement techniques – Radiated, radio-frequency, electromagnetic field immunity test
Amendment 1 (2007)
Amendment 2 (2010)
IEC 61000-4-13:2002, Electromagnetic compatibility (EMC) – Part 4-13: Testing and
measurement techniques – Harmonics and interharmonics including mains signalling at a.c.
power port, low-frequency immunity tests
Amendment 1 (2009)
Add the following new normative references as follows:

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– 4 – IEC 60947-1:2007/AMD2:2014

© IEC 2014

IEC 60092-504:2001, Electrical installations in ships – Part 504: Special features – Control

and instrumentation


IEC 60300-3-5:2001, Dependability management – Part 3-5: Application guide – Reliability

test conditions and statistical test principles


IEC 61508 (all parts), Functional safety of electrical/electronic/programmable electronic

safety-related systems


IEC 61649:2008, Weibull analysis


IEC 62061:2005, Safety of machinery – Functional safety of safety-related electrical,
electronic and programmable electronic control systems
IEC 62430:2009, Environmentally conscious design for electrical and electronic products
IEC 62474:2012, Material declaration for products of and for the electrotechnical industry
ISO 13849-1:2006, Safety of machinery – Safety-related parts of control systems – Part 1:
General principles for design
2 Definitions
Replace, in the alphabetical list, the existing references to these terms, modified by
Amendment 1, by the following new references:
Electronically controlled electromagnet . 2.3.36
Maximum cross-section . 2.3.35
Minimum cross-section . 2.3.34
Multiple tip contact system . 2.3.33
Replace, in the alphabetical list, the entry "Over-current discrimination" by the following new
entry:
Over-current selectivity . 2.5.23
Add, in the alphabetical list, the following new terms and references:
Flexible conductor . 2.3.32
Individual enclosure . 2.2.23
Insulation coordination barrier . 2.1.23

Rated control circuit supply voltage . 2.5.67
Rated control circuit voltage . 2.5.66
Rigid conductor . 2.3.31
Solid conductor . 2.3.29
Solid insulation . 2.1.22
Stranded conductor . 2.3.30

2.1 General terms
Add, at the end of the existing subclause, the following new terms and definitions:
2.1.22
solid insulation
solid insulating material interposed between two conductive parts

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IEC 60947-1:2007/AMD2:2014 – 5 –

© IEC 2014

2.1.23

insulation coordination barrier

solid insulating material that is not an integral part, provided for the purpose of increasing

either creepage distances or clearance distances or both


2.2 Switching devices


Add, at the end of the existing subclause, the following new term and definition:


2.2.23

individual enclosure

enclosure designed and dimensioned to contain one equipment only
2.3 Parts of switching devices
Add, after the existing definition 2.3.28 added by Amendment 1, the following new terms and
definitions and renumber the existing definitions 2.3.29 to 2.3.32 as 2.3.33 to 2.3.36
respectively:
2.3.29
solid conductor
conductor consisting of a single wire
NOTE 1 The solid conductor may be circular or shaped.
NOTE 2 Solid conductor is defined as class 1 conductor in IEC 60228, or by IEC 60344, or equivalent AWG/kcmil.
[461-01-06, modified]
2.3.30
stranded conductor
conductor consisting of a number of wires, all or some of which are wound in a helix
NOTE Stranded conductor is defined as class 2 conductor in IEC 60228, or by IEC 60344, or equivalent
AWG/kcmil.
[151-12-36, modified]
2.3.31
rigid conductor
solid or stranded conductor having wires of such diameters, or so assembled, that the
conductor is not suitable for use in a flexible cable

2.3.32
flexible conductor
stranded conductor having wires of diameters small enough and so assembled that the
conductor is suitable for use in a flexible cable
NOTE Flexible conductor is defined as class 5 or class 6 conductor in IEC 60228, or by IEC 60344, or equivalent
AWG/kcmil.
[461-01-11, modified]
2.5 Characteristic quantities
2.5.23
over-current discrimination
Replace the existing term by the new following term:

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– 6 – IEC 60947-1:2007/AMD2:2014

© IEC 2014

over-current selectivity




Replace, in the existing note of this definition, the word “discrimination” by “selectivity”.


Delete the existing source "[441-17-15]".


Add, after the existing definition 2.5.65, the following new terms and definitions:


2.5.66

rated control circuit voltage

U
c
rated voltage which is controlling the input signal of the control device
2.5.67
rated control circuit supply voltage
U
s
rated voltage applied to energize the power supply terminals of the control circuit
4 Characteristics
Add, in the existing table, the following new line:
Characteristic Symbol Subclause
Pole impedance of the switching device Z 4.3.7

Replace, in the existing line "Rated conditional short-circuit current", the symbol " – " by " I ",
q
as follows:
Characteristic Symbol Subclause
Rated conditional short-circuit current I 4.3.6.4
q

Replace the existing line “Rated control supply voltage” as follows:
Characteristic Symbol Subclause
Rated control circuit supply voltage U 4.5.1
s


4.3.6.1 Rated short-time withstand current (I )
cw
Replace the existing text of this subclause by the following new text:
The rated short-time withstand current of an equipment is the value of short-time current,
assigned to the equipment by the manufacturer, that the equipment can carry without
damage, under the test conditions specified in the relevant product standard.
4.3.6.4 Rated conditional short-circuit current
Replace the existing title of this subclause by the following new title:
4.3.6.4 Rated conditional short-circuit current (I )
q
Add, before the existing Subclause 4.4, the following new subclause:

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IEC 60947-1:2007/AMD2:2014 – 7 –

© IEC 2014

4.3.7 Pole impedance of the switching device (Z)


The pole impedance may be stated by the manufacturer and is determined by measuring the

voltage drop resulting from the current flowing through the pole.


4.5.1 Electrically or electronically controlled circuits

Replace the existing fourth dashed item, modified by Amendment 1, by the following new
dash:


– rated control circuit supply voltage U (a.c., d.c.), where applicable;
s


Replace the existing Note 1 added by Amendment 1 by the following new note:
NOTE 1 Distinction is made between the rated control circuit voltage U and the rated control circuit supply
c
voltage U which may be different from U due to the presence of built-in transformers, rectifiers, resistors,
s c
electronic circuitry, etc.
Delete the existing Note 2 added by Amendment 1.
Replace the existing paragraph after Note 2, added by Amendment 1, by the following new
paragraph:
The correct operating conditions are based upon a value of the control circuit supply voltage
not less than 85 % of its rated value U , with the highest value of control circuit current
s
flowing, nor more than 110 % of its rated value.
5.1 Nature of information
Replace the existing eighteenth dashed item under “Characteristics” by the following new
dash:
– control circuit supply voltage, kind of current and frequency, if different from those of the
control coil;
Add, in the existing list “Characteristics” after the item “suitability for isolation”, the following
two new dashed items:
– pole impedance of the switching device (Z);
– material declaration as per Annex W;
5.3 Instructions for installation, operation and maintenance
Move the first sentence of the second existing paragraph to the end of the first paragraph.

Replace the second sentence of the second paragraph by the following new sentence:
For equipment only suitable in environment A (see 7.3.1), the manufacturer shall provide the
following notice in documentation, available as information to potential customers and with the
product for users:
Add, after the existing Subclause 5.3, the following new subclause:
5.4 Environmental information
Material declarations according to Annex W shall be provided if required by the relevant
product standard.

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– 8 – IEC 60947-1:2007/AMD2:2014

© IEC 2014

6.1.1 Ambient air temperature


Replace, in the existing Note 1 “IEC 60439-1” by “IEC 61439 series”.


7.1.2.2 Glow wire testing


Replace, in the existing note, "IEC 60695-2-2" by "IEC 60695-11-5".


Add, at the end of existing note, the following new sentence:


The needle flame test is used as an alternative test for addressing flame retardancy requirements for shipboard
applications.

7.1.4 Clearances and creepage distances
Replace the existing text of this subclause by the following new three subclauses:
7.1.4.1 General
For equipment tested according to 8.3.3.4 of this standard, minimum values are given in
Table 13 and Table 15.
Electrical requirements are given in 7.2.3.
In the other cases, guidance for minimum values is given in the relevant product standard.
NOTE Depending on the risk level (severity of harm and the probability of occurrence), the non-accessibility to
hazardous-live parts is considered under normal service conditions (see 6.1) or under single-fault conditions (see
4.2 of IEC 61140:2001, 7.1.10 and Annex N).
7.1.4.2 Insulation coordination barriers for creepage distances
When solid insulation is used as an insulation coordination barrier to comply with required
creepage distances, the material used shall comply with the glow wire requirements in 7.1.2.2
or the flammability requirements in 7.1.2.3.
7.1.4.3 Insulation coordination barriers for clearance distances
When solid insulation is used as an insulation coordination barrier to comply with required
clearance distances and does not physically support or maintain the relative position of
uninsulated parts involved, the barrier material shall comply with the glow wire requirements
in 7.1.2.2 and shall conform to the glow-wire test requirements of 8.2.1.1.1 at a temperature
of 650 °C or the AI values in Table M.2. Alternatively the material shall comply with the
requirements in 7.1.4.2.

7.2.1.2 Limits of operation of power operated equipment
Replace, in the first existing paragraph, “control supply voltage” by “control circuit supply
voltage”.
Replace, in the existing paragraph, after the note, “rated control supply voltage” by “rated
control circuit supply voltage”.
Replace, in the first (one occurrence) and second dashed items (two occurrences) of the fifth
existing paragraph, introduced by Amendment 1, “rated control supply voltage” by “rated
control circuit supply voltage”.

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IEC 60947-1:2007/AMD2:2014 – 9 –

© IEC 2014

7.2.1.4 Limits of operation of shunt releases


Replace, in the existing paragraph, “rated control supply voltage” by “rated control circuit

supply voltage”.


7.2.2.5 Control circuits

Add, after the existing text, the following new paragraph:


Digital inputs and/or digital outputs contained in switchgear and controlgear, and intended to
be compatible with programmable logic controllers (PLCs) are covered by Annex S.

7.2.2.8 Other parts
Replace, in the existing text, "plastics and insulating materials" by "insulating parts".
7.2.3.3 Clearances
Replace, in the second sentence of the second paragraph, "are higher than" by "are equal to
or higher than".
7.2.3.5 Solid insulation
Delete the last existing sentence of this subclause.
Add, at the end of this subclause, the following new note:
NOTE For more information on the design of solid insulation, see 5.3.1 of IEC 60664-1:2007.
Add, before the existing Subclause 7.3, the following new subclause:
7.2.8 Pole impedance
Where the pole impedance is given, it shall be tested according to 8.3.3.8.
7.3.3.1 Equipment not incorporating electronic circuits
Replace the existing text of this subclause by the following new text:
The requirements for electromagnetic emissions for equipment not incorporating electronic
circuits are deemed to be satisfied, and no verification is necessary.

NOTE For equipment not incorporating electronic circuits, electromagnetic disturbances can only be generated by
equipment during occasional switching operations. The duration of the disturbances is less than 200 ms in accordance
with CISPR 22.
The frequency, the level and the consequences of these emissions are considered as part of
the normal electromagnetic environment of low-voltage installations.
7.3.3.2.1 Limits for high-frequency emissions
Replace the first three existing paragraphs of this subclause by the following new text and
new note:
The high-frequency (greater than 9 kHz) continuous emissions from equipment incorporating
electronic switching circuits shall not exceed the limits specified in the relevant product
standard, based on CISPR 11 for environment A and for environment B.
NOTE One-time disturbances no longer than 200 ms need no further evaluation.

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– 10 – IEC 60947-1:2007/AMD2:2014

© IEC 2014

8.2 Compliance with constructional requirements

th

Replace, in the 4 existing dash of the list, “the mechanical properties of terminals” by “the

mechanical and electrical properties of terminals”.


8.2.4.1 General conditions for tests

Replace, in the second sentence, the reference to "IEC 60028" by "IEC 60228".


8.2.4.7 Electrical performance of screwless-type clamping units

Replace, in the existing Note 1 introduced by Amendment 1, the references "(2.3.30)" and

"(2.3.31)" by "(2.3.24)" and "(2.3.35)" respectively.
Replace the existing Note 2 introduced by Amendment 1 by the following new note:
NOTE 2 For the largest cross-sectional area the test current generally applied is I or I declared for the
th the
product. For the smallest cross-sectional area, the test current is given in Table 4 and Table 5 of IEC 60947-7-
1:2009.
8.2.4.8 Ageing test for screwless-type clamping units
Replace, in the existing Note 1 introduced by Amendment 1, the references "(2.3.30)" and
"(2.3.31)" by "(2.3.34)" and "(2.3.35)" respectively.
Replace the existing Note 2 introduced by Amendment 1 by the following new note :
NOTE 2 For the largest cross-sectional area the test current generally applied is I or I declared for the
th the
product. For the smallest cross-sectional area, the test current is given in Table 4 and Table 5 of IEC 60947-7-
1:2009.
8.3.2 General test conditions
Replace, in the existing note, “IEC 60439” by “IEC 61439 series”.
8.3.2.1 General requirements
Delete the existing note.
8.3.2.2.3 Recovery voltage
Replace, in the existing Note 1, "system voltage" by "supply network voltage".
8.3.3.2.1 Power operated equipment

Replace, in the second existing paragraph, introduced by Amendment 1, “rated control supply
voltage” by “rated control circuit supply voltage”.
Replace the fifth existing paragraph added by Amendment 1 by the following new paragraph:
The value of the capacitor shall be
C = 30 + 200 000 / (f × U)
where
C is expressed in nF;
f is the minimum rated frequency expressed in Hz;
U is the maximum value of U expressed in V.
s

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IEC 60947-1:2007/AMD2:2014 – 11 –

© IEC 2014

8.3.3.3.1 Ambient air temperature


Replace the second existing paragraph by the following new paragraph:


During the test, the ambient temperature shall be between +10 °C and +40 °C and shall not

vary by more than 10 K. The ambient temperature shall not vary by more than 3 K during the

last quarter of the test or the last hour of the test, whichever is the shorter. The test shall be

conducted until this condition is achieved.


Delete the third existing paragraph of this subclause.


8.3.3.4.1 Type tests
Delete Note 2 in the existing item 1).
Renumber, in the existing item 1), “Note 3” and “Note 4” added by Amendment 1 as “Note 2”
and “Note 3” respectively.
Replace, in the existing item 3) c), the text modified by Amendment 1 by the following new
text and new note:
The test voltage shall be applied to for 60 s in accordance with items i), ii) and iii) of 2) c)
above.
NOTE For devices already type-tested according to this standard and its Amendment 1 or earlier, a re-testing
according to 60 s is not necessary.
Replace, in the existing item 6), the existing text “Under consideration” by "Equipment with
d.c. ratings only shall be tested with d.c. test voltage".
Add, before the existing Subclause 8.3.4, the following new subclause:
8.3.3.8 Pole impedance
The pole impedance shall be determined during the test and with the conditions given in
8.3.3.3.4. The test in an enclosure is not deemed necessary even if the switching device can
be used in an individual enclosure.
The voltage drop U shall be measured between the line and load terminals (terminals
d
included) of the switching device using the same measuring points as for the temperature
rise. The measurement shall be performed after a time sufficient for the temperature-rise to
reach a steady-state value.

The impedance per pole is defined as follows:
Z = U / I [Ω]
d th
The declared value (see 5.1 modified by this Amendment 2), in the case of multiple identical
poles, shall
...