IEC 60947-1:2007/AMD1:2010

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

Supplementary document to the sectional specification. Contains requirements for style, layout and minimum content of detail specifications.

Amendement 1 - Appareillage à basse tension - Partie 1: Règles générales

Document supplémentaire à la spécification intermédiaire. Contient les exigences concernant le contenu minimal des spécifications particulières.

General Information

• Status: Published
• Publication Date: 07-Dec-2010
• ICS: 29.130.20 - Low voltage switchgear and controlgear
• ICS: 31.140 - Piezoelectric devices
• Technical Committee: SC 121A - Low-voltage switchgear and controlgear
• Drafting Committee: MT 5 - TC 121/SC 121A/MT 5
• Current Stage: DELPUB - Deleted Publication
• Completion Date: 22-Apr-2020

Relations

• Revised: IEC 60947-1:2020 - Low-voltage switchgear and controlgear - Part 1: General rules
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 60947-1

®

Edition 5.0 2010-12



INTERNATIONAL



STANDARD



NORME
INTERNATIONALE
AMENDMENT 1
AMENDEMENT 1
Low-voltage switchgear and controlgear –
Part 1: General rules

Appareillage à basse tension –
Partie 1: Règles générales


IEC 60947-1:2007/A1:2010

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---------------------- Page: 2 ----------------------
IEC 60947-1


®

Edition 5.0 2010-12



INTERNATIONAL



STANDARD



NORME
INTERNATIONALE
AMENDMENT 1
AMENDEMENT 1
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
W
CODE PRIX
ISBN 978-2-88912-291-2
ICS 29.130.20
® Registered trademark of the International Electrotechnical Commission
Marque déposée de la Commission Electrotechnique Internationale

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– 2 – 60947-1 Amend.1 Ó IEC:2010



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

17B/1710/FDIS 17/1721/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 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.

_____________
1 General
Replace the existing note of this clause by the following new note:
NOTE The product standards forming the series of IEC standards covering low-voltage switchgear and
controlgear are:
IEC 60947-2: Part 2: Circuit-breakers
IEC 60947-3: Part 3: Switches, disconnectors, switch-disconnectors and fuse combination units
IEC 60947-4: Part 4: Contactors and motor-starters
IEC 60947-5: Part 5: Control-circuit devices and switching elements

IEC 60947-6: Part 6: Multiple function equipment
IEC 60947-7: Part 7: Ancillary equipment
IEC 60947-8: Part 8: Control units for built-in thermal protection (PTC) for rotating electrical machines.

---------------------- Page: 4 ----------------------
60947-1 Amend.1 Ó IEC:2010 – 3 –


1.2 Normative references


Add the following normative references to the existing list:


IEC 60664-3:2003, Insulation coordination for equipment within low-voltage systems – Part 3:

Use of coating, potting or moulding for protection against pollution


IEC 60664-5:2007, Insulation coordination for equipment within low-voltage systems – Part 5:

Comprehensive method for determining clearances and creepage distances equal to or less

than 2 mm


IEC 60695-2-12, Fire hazard testing – Part 2-12: Glowing/hot-wire based test methods –
Glow-wire flammability test method for materials
IEC 60999-1:1999, Connecting devices – Electrical copper conductors – Safety requirements
for screw-type and screwless-type clamping units – Part 1: General requirements and
particular requirements for clamping units for conductors from 0,2 mm² up to 35 mm²
(included)
IEC 60999-2:2003, Connecting devices – Electrical copper conductors – Safety requirements
for screw-type and screwless-type clamping units – Part 2: Particular requirements for
2 2
clamping units for conductors above 35 mm up to 300 mm (included)
IEC 61557-2, Electrical safety in low voltage distribution systems up to 1 000 V a.c. and 1 500
V d.c. – Equipment for testing, measuring or monitoring of protective measures – Part 2:
Insulation resistance

2 Definitions
Replace, in the alphabetical list, the existing references to these terms by the following new
references:
Clamping unit . 2.3.26
Multiple tip contact system . 2.3.29
Prepared conductor . 2.3.28
Screw-type terminal . 2.3.24
Screwless-type terminal . 2.3.25
Unprepared conductor . 2.3.27


This correction does not apply to the English text.
Add, in the alphabetical list, the following new terms and references:
Connecting device . 2.3.22
Electronically controlled electromagnet . 2.3.32
Electronic overload relay with current or voltage asymmetry function . T.2.2
Electronic overload relay with ground/earth fault detection function . T.2.1
Electronic overload relay with phase reversal function . T.2.3
Electronic overload relay with over voltage function . T.2.4
Electronic overload relay with under power function . T.2.6
External control device . U.1.1
Inhibit current . T.2.5
Maximum cross-section . 2.3.31
Minimum cross-section. 2.3.30
Non-universal clamping unit. 2.3.26.2
Non-universal terminal . 2.3.25.2

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– 4 – 60947-1 Amend.1 Ó IEC:2010


Push-wire terminal . 2.3.25.3

Terminal . 2.3.23

Universal clamping unit . 2.3.26.1

Universal terminal. 2.3.25.1




Replace the existing terms and definitions 2.3.22 to 2.3.28 by the following new terms and

definitions:


2.3.22

connecting device

a device for the electrical connection of one (or more) conductor(s), comprising one (or more)
terminal(s), either fixed to a base or forming an integral part of the equipment
[IEC 60999-1:1999, 3.3]
2.3.23
terminal
conductive part of one pole of a device for electrical connection to external circuit, composed
of one or more clamping unit(s) and insulation if necessary
[IEC 60999-1:1999, 3.2, modified]
2.3.24
screw-type terminal
terminal intended for the connection and disconnection of conductors or for the inter-
connection of two or more conductors, the connection being made, directly or indirectly, by
means of screws or nuts of any kind
NOTE Examples are given in Annex D.
2.3.25
screwless-type terminal
terminal intended for the connection and disconnection of conductors or for the
interconnection on two or more conductors, the connection being made, directly or indirectly,
by means of springs, wedges, eccentrics or cones, etc.
NOTE Examples are given in Annex D.
2.3.25.1
universal terminal
terminal for the connection and disconnection of all types of conductors (rigid and flexible)

[IEC 60998-2-2:2002, 3.101.1]
2.3.25.2
non-universal terminal
terminal for the connection and disconnection of a certain kind of conductor only (for example,
solid conductors only or rigid [solid and stranded] conductors only)
[IEC 60998-2-2:2002, 3.101.2]
2.3.25.3
push-wire terminal
non-universal terminal in which the connection is made by pushing in rigid (solid or stranded)
conductors
[IEC 60998-2-2:2002, 3.101.3]

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60947-1 Amend.1 Ó IEC:2010 – 5 –


2.3.26


clamping unit

the part(s) of the terminal necessary for the mechanical clamping and the electrical

connection of the conductor(s), including the parts which are necessary to ensure the correct

contact pressure

[IEC 60999-1:1999, 3.1]


2.3.26.1

universal clamping unit

clamping unit intended for all types of conductors

2.3.26.2
non-universal clamping unit
clamping unit intended for certain types of conductors only, for example:
– push-wire clamping unit for solid conductors only
– push-wire clamping unit for rigid (solid and stranded) conductors only
NOTE On push-wire clamping unit the connection is made by simple insertion of rigid conductors. (see 7.1.8.1)
2.3.27
unprepared conductor
conductor which has been cut and the insulation of which has been removed for insertion into
a terminal
NOTE A conductor the shape of which is arranged for introduction into a terminal or the strands of which are
twisted to consolidate the end is considered to be an unprepared conductor.
2.3.28
prepared conductor
conductor, the strands of which are soldered or the end of which is fitted with a cable lug,
eyelet, etc.

Add, after definition 2.3.28, the following new terms and definitions 2.3.29 to 2.3.32 :
2.3.29
multiple tip contact system
contact system comprising more than one contact gap per pole, which can be switched, in
series and/or in parallel

2.3.30
minimum cross-section
value of the smallest connectable conductor cross-section stated by the manufacturer as
suitable for the terminal
NOTE The manufacturer may declare several minimum cross-sections depending on the type of conductor, for
example rigid, stranded, flexible, with or without ferrule.
2.3.31
maximum cross-section
value of the largest connectable conductor cross-section stated by the manufacturer as
suitable for the terminal
NOTE 1 The manufacturer may declare several maximum cross-sections depending on the type of conductor, for
example rigid, stranded, flexible, with or without ferrule.
NOTE 2 The term “rated cross-section” used in IEC 60947-7-1 and IEC 60999-2 and the term “rated connecting
capacity” of a clamping unit used in IEC 60999-1 are considered equivalent when referring to certain thermal,

---------------------- Page: 7 ----------------------
– 6 – 60947-1 Amend.1 Ó IEC:2010


mechanical and electrical requirements, as stated by the manufacturer and as specified in their relevant product

standard.

2.3.32

electronically controlled electromagnet

electromagnet in which the coil is controlled by a circuit with active electronic elements



4 Characteristics


In the existing line "Rated ultimate short-circuit breaking capacity" of the list, replace "4.3.2.4"

a
by " ".

a
In the existing line "Rated uninterrupted current" of the list, replace " " by "4.3.2.4".
4.5.1 Electrical control circuits
Replace the existing title and text of this subclause by the following:
4.5.1 Electrically or electronically controlled circuits
Characteristics of electrical and electronic control circuits:
– type of current;
– rated frequency or d.c.;
– rated control circuit voltage U (a.c., d.c.);
c
– rated control supply voltage U (a.c., d.c.), where applicable;
s
– nature of external control circuit devices (contacts, sensors, optocouplers, electronic
active components, etc);
– power consumption.
NOTE 1 In case of an electrical control circuit a distinction has been made above between the control circuit
voltage U , which is the voltage which would appear across the "a" contacts (see 2.3.12) in the control circuit, and
c
the control supply voltage U , which is the voltage applied to the input terminals of the control circuit of the
s
equipment and may be different from the control circuit voltage, due to the presence of built-in transformers,
rectified, resistors, etc.
NOTE 2 In case of an electronically control circuit a distinction is made between the control circuit voltage U ,
c
which is the controlling input signal, and the control supply voltage U , which is the voltage applied to energize the
s
power supply terminals of the control circuit equipment and may be different from U due to the presence of built-in
c
transformers, rectifiers, resistors, electronic circuitry, etc.
The rated control circuit voltage and rated frequency, if any, are the values on which the
operating and temperature-rise characteristics of the control circuit are based. The correct

operating conditions are based upon a value of the control supply voltage not less than 85 %
of its rated value, with the highest value of control circuit current flowing, nor more than
110 % of its rated value.
The electronic part of an electronically controlled electromagnet may form an integral part or a
separate part provided it is an intrinsic function of the device. In both cases, the device shall
be tested with this electronic part mounted as in normal use.
Annex U gives examples and illustrations of different circuit configurations.
The ratings and characteristics of control circuit devices shall comply with the requirements of
IEC 60947-5 (see the note of Clause 1).
4.7 Relays and releases
Add, at the end of the existing list, the following new dashed item:

---------------------- Page: 8 ----------------------
60947-1 Amend.1 Ó IEC:2010 – 7 –


- extended functions as given in Annex T.


4.8 Co-ordination with short-circuit protective devices (SCPD)

Replace the existing note by the following new note:

NOTE IEC/TR 61912-1 gives guidance on co-ordination with SCPDs.

5.1 Nature of information


In the list of characteristics, add after “- rated impulse withstand voltage (see 4.3.1.3)”, the

following new dashed item:

– relay or release characteristics (see 4.7);
Add the following new text before the existing note of this subclause:
– length of insulation to be removed before insertion of the conductor into the terminal;
– maximum number of conductors which may be clamped.
For non-universal screwless terminals:
– “s” or "sol" for terminals declared for rigid-solid conductors;
– "r" for terminals declared for rigid (solid and stranded) conductors;
– "f" for terminals declared for flexible conductors .
In the case of electronically controlled electromagnets, other information may also be
necessary, for example control circuit configuration (see 4.5 and Annex U).
5.2 Marking
Add, at the end of this subclause, the following new paragraphs:
In the case of electronically controlled electromagnets, information other than that given in 5.1
may also be necessary (see also 4.5 and Annex U).
The indication "s", "sol", "r" or "f" for non-universal screwless terminals shall be marked on the
device or, if the space available is not sufficient, on the smallest package unit or in technical
information provided with the product.
In the case of a group of terminals located together, a single marking on the device is
acceptable.

7.1.2.1 General materials requirements
Replace the first paragraph of this subclause by the following new paragraph:
Parts of insulating materials which might be exposed to thermal stresses due to electrical
effects within the equipment shall not be adversely affected by abnormal heat and by fire.
Delete the existing last paragraph of this subclause.
7.1.2.2 Glow wire testing
Replace the existing first three paragraphs of this subclause by the following new text:
The suitability of materials used is verified by:
a) making tests on the equipment; or

---------------------- Page: 9 ----------------------
– 8 – 60947-1 Amend.1 Ó IEC:2010


b) making tests on sections taken from the equipment; or

c) making tests on any parts of identical material having representative thickness; or


d) providing data from the insulating material supplier fulfilling the requirements according to

IEC 60695-2-12.

The suitability shall be determined with respect to resistance to abnormal heat and fire.


The manufacturer shall indicate which methods, amongst a), b), c) and d) shall be used.


7.1.2.3 Test based on flammability category


Add, after the existing text, the following new paragraph:
Alternatively, the manufacturer may provide data from the insulating material supplier fulfilling
the requirements given in Annex M.
7.1.7.1 Additional constructional requirements
Replace the existing third dashed item of the list by the following new dashed item:
– visibility of all moving main contacts.
7.1.8.1 Constructional requirements
Replace the second paragraph of this subclause by the following new paragraph:
Terminal connections shall be such that the force to connect the conductors may be applied
by screws, screwless-type or other equivalent means so as to ensure that the necessary
contact pressure is maintained.
Add, after the existing Note 1 of this subclause, the following new text:
Screwless-type clamping units, unless otherwise specified by the manufacturer, shall accept
rigid and flexible conductors as indicated in Table 1.
On screwless-type clamping unit, the connection or disconnection of conductors shall be
made as follows:
– on universal clamping units by the use of a general purpose tool or a convenient device,
integral with the clamping unit to open it for the insertion or withdrawal of the conductors;
– on push-wire clamping units by simple insertion. For the disconnection of the conductors

an operation other than a pull only on the conductor shall be necessary. The use of a
general purpose tool or of a convenient device, integral with the clamping unit is allowed
in order to "open" it and to assist the insertion or the withdrawal of the conductor.
7.1.10.2 Protective earth terminal
In the last paragraph of this subclause, replace the reference to 2.1.1.5 by a reference to
2.1.15.
7.2.1.2 Limits of operation of power operated equipment
Add, after the existing fourth paragraph of this subclause, the following new text:
The limits between which an equipment, with an electronically controlled electromagnet, shall
drop out and open fully are
- for d.c.: 75 % to 10 % of their rated control supply voltage U ,
s

---------------------- Page: 10 ----------------------
60947-1 Amend.1 Ó IEC:2010 – 9 –


- for a.c.: 75 % to 20 % of their rated control supply voltage U , or 75 % to 10 % of their
s

rated control supply voltage U if specified by the manufacturer.
s


Add, after the last existing paragraph of this subclause, the following new paragraph:


The drop out time may need to be specified for particular applications. In this case the drop

out time shall be measured during the test associated with the verification of this subclause.


7.2.3 Dielectric properties

Add, at the end of the first paragraph, the following new second sentence:

For reduced clearances and creepage distances through the use of coating see IEC 60664-3;
for clearances and creepage distances equal to or less than 2 mm see IEC 60664-5.
7.3.1 General
Add, after the existing Note 2 of this subclause, the following new paragraph:
For the purpose of this standard, the phrase “electronic circuit” excludes circuits in which all
components are passive (including diodes, resistors, varistors, capacitors, surge suppressors,
inductors).
7.3.2.2 Equipment incorporating electronic circuits
Delete the existing second paragraph of this subclause.
8.2.4 Mechanical properties of terminals
Replace the existing title of this subclause by the following new title:
8.2.4 Mechanical and electrical properties of terminals

8.2.4.2 Tests of mechanical strength of terminals
Replace, in the existing first paragraph of this subclause, "cross-sectional area" by " cross-
section".
Add, after the existing first paragraph of this subclause, the following new paragraph:

Screwless-type clamping unit according to 7.1.8.1 are tested with conductors of the maximum
cross-section.
8.2.4.3 Testing for damage to and accidental loosening of conductors (flexion test)
Replace, in the existing item a) of this subclause, "smallest cross-section" by "minimum cross-
section".
Replace, in the existing item b) of this subclause, "largest cross-section" by "maximum cross-
section".
Replace, in the existing item c) of this subclause, "smallest and largest cross-sections" by
"minimum and maximum cross-sections".

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– 10 – 60947-1 Amend.1 Ó IEC:2010


8.2.4.4.1 Round copper conductors


Replace the existing third paragraph of this subclause by the following paragraph:


The force shall be applied without jerks for 1 min, in the direction of the axis of the conductor.


8.2.4.5 Test for insertability of unprepared round copper conductors having the

maximum specified cross-section


In the existing title of this subclause, replace "maximum specified cross-section" by "maximum
cross-section".

Add, after the existing subclause 8.2.4.6, the two following new subclauses 8.2.4.7 and
8.2.4.8:
8.2.4.7 Electrical performance of screwless-type clamping units
Subclauses 9.8 of IEC 60999-1 and 9.8 of IEC 60999-2 apply.
NOTE 1 The terms “smallest cross-sectional area” and “largest cross-sectional area” of IEC 60999 series are
respectively "minimum cross section" (2.3.30) and "maximum cross section" (2.3.31) defined in this standard.
NOTE 2 The test current generally applied is I or I declared for the product.
th the
The detailed test requirements may be adapted in the product standards.
NOTE 3 The product standard should consider the practicality of the detailed test requirements.
8.2.4.8 Ageing test for screwless-type clamping units
Subclauses 9.10 of IEC 60999-1 and 9.10 of IEC 60999-2 apply.
NOTE 1 The terms “smallest cross-sectional area” and “largest cross-sectional area” of IEC 60999 series are
respectively "minimum cross section" (2.3.30) and "maximum cross section" (2.3.31) defined in this standard.
NOTE 2 The test current generally applied is I or I declared for the product.
th the
The detailed test requirements may be adapted in the product standards.
NOTE 3 The product standard should consider the practicality of the detailed test requirements.
8.2.5.2.1 Dependent and independent manual operation
Add, after the existing third paragraph of this subclause, the following new paragraph:

Where the device has more than one contact system in series, all contact systems that are in
series shall be held in the closed position.
Add, at the end of this subclause, the following new paragraph:
Verification shall be made according to 8.2.5.3.1.
8.2.5.2.2 Dependent power operation
Add, after the first paragraph of this subclause, the following new paragraph:
Where the device has more than one contact system in series, all contact systems that are in
series shall be held in the closed position.

---------------------- Page: 12 ----------------------
60947-1 Amend.1 Ó IEC:2010 – 11 –


8.2.5.2.3 Independent power operation


Add, after the first paragraph of this subclause, the following new paragraph:


Where the device has more than one contact system in series, all contact systems that are in

series shall be held in the closed position.


8.3.3.2.1 Power operated equipment


Add, at the end of this subclause, the following new text:


In the case of a power operated equipment with electronically controlled electromagnet,
supplied with a.c., where a drop out range is declared with limits between 75 % to 10 % of
their rated control supply voltage U , the equipment shall, in addition, be submitted to the
s
capacitive drop out test as follows:
A capacitor C shall be inserted in series in the supply circuit U , the total length of the
s
connecting conductors being £3 m. The capacitor is short-circuited by a switch of negligible
impedance. The supply voltage shall then be adjusted to 110 % U .
s
It shall be verified that the equipment drops out when the switch is operated to the open
position.
The value of the capacitor shall be
C (nF) = 30 + 200 000 / (f ´ U )
s
where
f is the minimum rated frequency (Hz);
U is the maximum rated supply voltage (V).
s
For example for a coil rated 12…24 V – 50 Hz, the capacitor value is 196 nF (calculation
made with U max).
s
The test voltage is the highest value of the declared rated supply voltage range U .
s
NOTE The value of the capacitor simulates a typical control wiring of 100 m long cable of 1,5 mm2
(0,3 nF/m that is 30 nF for 100 m) connected to a static output having a 1,3 mA leakage current
(200 000 in the formu
...