IEC 60309-4:2006+AMD1:2012 CSV

IEC 60309-4 ®
Edition 1.1 2012-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Plugs, socket-outlets and couplers for industrial purposes –
Part 4: Switched socket-outlets and connectors with or without interlock

Prises de courant pour usages industriels –
Partie 4: Prises de courant et prises mobiles avec interrupteur, avec ou sans
dispositif de verrouillage
IEC 60309-4:2006+A1:2012
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IEC 60309-4 ®
Edition 1.1 2012-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Plugs, socket-outlets and couplers for industrial purposes –

Part 4: Switched socket-outlets and connectors with or without interlock

Prises de courant pour usages industriels –

Partie 4: Prises de courant et prises mobiles avec interrupteur, avec ou sans

dispositif de verrouillage
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX CH
ICS 29.120.30 ISBN 978-2-88912-052-9

– 2 – 60309-4  IEC:2006+A1:2012
CONTENTS
FOREWORD . 3

1 Scope . 5
2 Definitions . 5
3 Normative references . 7
4 General . 7
5 Standard ratings . 8
6 Classification . 8
7 Marking . 9
8 Dimensions . 11
9 Protection against electric shock . 11
10 Provision for earthing . 12
11 Terminals . 12
12 Interlocks, switches and their components . 12
13 Resistance to ageing of rubber and thermoplastic material . 17
14 General construction . 17
15 Construction of socket-outlets . 17
16 Construction of plugs and connectors . 17
17 Construction of appliance inlets . 17
18 Degrees of protection . 17
19 Insulation resistance and dielectric strength . 17
20 Breaking capacity . 18
21 Normal operation . 18
22 Temperature rise . 18
23 Flexible cable and their connection . 20
24 Mechanical strength . 20
25 Screws, current-carrying parts and connections . 21
26 Creepage distances, clearances and distances through sealing compound . 21
27 Resistance to heat, fire and tracking . 21
28 Corrosion and resistance to rusting . 21
29 Conditional short-circuit current withstand test . 21

Figure 101 – Actuator applied force F . 22
Figure 102 – Example of apparatus for checking the withdrawal force . 22

Table 101 − Withdrawal force with respect to ratings . 14
Table 8 . 19
Table 102 – Actuator test force F . 20

60309-4  IEC:2006+A1:2012 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
PLUGS, SOCKET-OUTLETS AND COUPLERS
FOR INDUSTRIAL PURPOSES –
Part 4: Switched socket-outlets and connectors
with or without interlock
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,
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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-
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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
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
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services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
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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) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.

This consolidated version of IEC 60309-4 consists of the first edition (2006) [documents
23H/189/FDIS and 23H/192/RVD] and its amendment 1 (2012) [documents 23H/276/FDIS
and 23H/281/RVD]. It bears the edition number 1.1.
The technical content is therefore identical to the base edition and its amendment and
has been prepared for user convenience. A vertical line in the margin shows where the
base publication has been modified by amendment 1. Additions and deletions are
displayed in red, with deletions being struck through.

– 4 – 60309-4  IEC:2006+A1:2012
International Standard IEC 60309-4 has been prepared by subcommittee 23H: Plugs and
socket-outlets for industrial purposes, of IEC technical committee 23: Electrical accessories.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
This standard is to be read in conjunction with IEC 60309-1 (1999) and IEC 60309-2 (1999).
Part 1 comprises clauses of a general character and the subsequent parts of the series deal
with particular types.
The clauses of the subsequent parts supplement or modify the corresponding clauses in Part 1.
Where the text of subsequent parts indicates an "addition" to or a "replacement" of the relevant
requirement, test specification or explanation of Part 1, these changes are made to the relevant
text of Part 1, which then becomes part of the standard. Where no change is necessary, the
words "This clause of Part 1 is applicable" are used.
Clauses, subclauses, figures, tables and notes which are additional to those in Part 1 are
numbered starting from 101.
The IEC 60309 series, under the general title Plugs, socket-outlets and couplers for industrial
purposes comprises the following parts:
Part 1: General requirements
Part 2: Dimensional interchangeability requirements for pin and contact-tube accessories
Part 4: Switched socket-outlets and connectors with or without interlock
The committee has decided that the contents of the base publication and its amendments 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 publication using a colour printer.

60309-4  IEC:2006+A1:2012 – 5 –
PLUGS, SOCKET-OUTLETS AND COUPLERS
FOR INDUSTRIAL PURPOSES –
Part 4: Switched socket-outlets and connectors
with or without interlock
1 Scope
This clause of Part 1 or Part 2 is applicable except as follows:
Replacement of the first paragraph by the following text:
This part of IEC 60309 applies to self-contained products that combine within a single
enclosure, a socket-outlet or connector according to IEC 60309-1 or IEC 60309-2 and a
switching device, with a rated operating voltage not exceeding 690 1 000 V d.c. or a.c. and
500 Hz , and a rated current not exceeding 250 800 A, primarily intended for industrial use,
either indoors or outdoors.
These accessories are intended to be installed by instructed persons (Amendment 1:2001 of
IEC 60050-195:1998, 195-04-02) or skilled persons (Amendment 1:2001 of
IEC 60050-195:1998, 195-04-01) only.
These products may incorporate an interlock and/or protective devices.
2 Definitions
This clause of Part 1 or Part 2 is applicable, except as follows:
Deletion of definitions 2.6 to 2.9.
Addition:
2.101
switched socket-outlet or connector
accessory containing in a single enclosure a switching device and a socket-outlet or
connector, intended to be used in combination. It can be either interlocked or non-interlocked
2.102
interlocked socket-outlet or connector
socket-outlet or connector associated with an interlock
2.103
switching device
device designated to make or break the current in one or more electric circuits
[IEV 441-14-01]
2.103.1
mechanical switching device
switching device designed to close and open one or more electric circuits by means of
separable contacts
[IEV 441-14-02]
– 6 – 60309-4  IEC:2006+A1:2012
2.103.1.1
switch (mechanical)
mechanical switching device capable of making, carrying and breaking currents under normal
circuit conditions, which may include specified operating overload conditions and also
carrying, for a specified time, currents under specified abnormal circuit conditions such as
those of short-circuit
[IEV 441-14-10]
NOTE A switch may be capable of making, but not breaking short-circuit currents.
2.103.1.1.1
switch-disconnector
switch, which in the open position complies with the requirements specified for the isolating
function
[IEV 441-14-12, modified]
NOTE This definition differs from IEV 441-14-05 by referring to isolating function instead of the requirements
specified for a disconnector.
2.103.1.2
contactor
mechanical switching device having only one position of rest, operated otherwise than by
hand, capable of making, carrying and breaking currents under normal circuit conditions,
including operating overload conditions
[IEV 441-14-33]
2.103.2
associated switching device
separate switching device which can be replaced independently
2.103.3
integral switching device
switching device constructed as a part of a socket-outlet or connector covered by this
standard, where neither the switching device nor the socket-outlet or connector can be
replaced independently
2.104
isolation (isolating function)
function intended to cut off the supply from all or a discrete section of the installation, by
separating the installation or section from every source of electrical energy for reasons of
safety (see IEC 60947-1 and IEC 61140 )
2.105
utilization category
〈switching device〉 combination of specified requirements related to the conditions in which the
switching device fulfils its purpose, selected to represent a characteristic group of practical
applications
[IEV 441-17-19, modified]
NOTE The specified requirements may concern e.g. the values of making capacities (if applicable), breaking
capacities and other characteristics, the associated circuits under the relevant conditions of use and behaviour.
—————————
IEC 61140, Protection against electric chock – Common aspects for installation and equipment

60309-4  IEC:2006+A1:2012 – 7 –
2.106
interlock or interlocking device
device, either electrical or electronic or mechanical or a combination of these, which makes
the operation of a piece of product dependent upon the condition, position or operation of one
or more other pieces of product
2.107
control circuit device
electrical device intended for the controlling, signaling, interlocking, etc. of switchgear and
controlgear (see IEC 60947-1, 2.1.1)
2.108
pilot contact
auxiliary electric contact for use in a control or monitoring or interlock function
NOTE Pilot contact is not considered to be a pole.
2.109
latching device
part of the interlock mechanism provided to hold a plug or appliance-inlet in the socket-outlet
or connector
3 Normative references
This clause of Part 1 or Part 2 is applicable, except as follows:
Addition:
IEC 60073, Basic and safety principles for man-machine interface, marking and identification -
Coding principles for indicators and actuators
IEC 60417-DB:2002 , Graphical symbols for use on equipment
IEC 60617-DB:2001 , Graphical Symbols for diagrams
IEC 60947-1:2004, Low-voltage switchgear and controlgear – Part 1: General rules
IEC 60947-4-1, Low-voltage switchgear and controlgear – Part 4-1: Contactors and motor-
starters – Electromechanical contactors and motor-starters
IEC 60947-5-1:2003, Low-voltage switchgear and controlgear – Part 5-1: Control circuit
devices and switching elements – Electromechanical control circuit devices
IEC 61032, Protection of persons and equipment by enclosures – Probes for verification
IEC 61058-1, Switches for appliances – Part 1: General requirements
4 General
This clause of Part 1 or Part 2 is applicable except as follows:
—————————
“DB” refers to the IEC on-line database.
“DB” refers to the IEC on-line database.

– 8 – 60309-4  IEC:2006+A1:2012
Addition:
4.101 Components incorporated or integrated in products (e.g. flexible cable, current cut-
outs, thermal cut-outs, safety transformers, switches, fuses, residual current devices,
lampholders and connecting devices) shall comply with the relevant standards as far as they
reasonably apply.
5 Standard ratings
This clause of Part 2 is applicable except as follows:
5.101 Replacement:
5.101 Standard IP ratings are
– IP44
– IP67
– IP66/IP67
For switched socket-outlet with or without interlock according to 6.1.101, the whole unit can
have a degree of protection different from IP44 or IP67 or IP66/IP67 but not lower than IP44
(see also 8.1).
6 Classification
This clause of Part 1 or Part 2 is applicable, except as follows:
6.1.1 Replacement:
6.1.1 According to purpose: socket-outlets, connectors
Deletion of 6.1.5.
Addition:
6.1.101 According to switching devices and interlock facilities:
– products with a switching device and without an interlock;
– products with a switching device and with an interlock.
6.1.102 According to the operation of the interlock/switching device
– manually;
– automatically (electrically and/or electronically);
– combination of the above.
NOTE Inserting the plug is not considered a manual operation of the interlock/switching device.
6.1.103 According to the mechanical switching device
– switch;
– switch-disconnector;
– contactor;
– other devices with suitable switch rating.

60309-4  IEC:2006+A1:2012 – 9 –
6.1.104 According to suitability for isolation of the switching device
– suitable for isolation;
– not suitable for isolation.
6.1.105 According to whether the interlock system has a latching device
– with latching device (mechanical interlock);
– without latching device (electrical interlock).
6.1.106 According to the presence of a protective device
– with protective device;
– without protective device.
7 Marking
This clause of Part 1 or Part 2 is applicable, except as follows:
7.1 Addition:
– indication of the open and closed position of the switching device for products with
isolating function according to 6.1.104;
– indication of the type of switching device.
7.2 Addition:
Open position and/or
OFF
IEC 60417-5008
Closed position and/or
ON
IEC 60417-5007
Switch or
IEC 60617 – S00227
IEC 60947-3
Switch-disconnector
IEC 60617 – S00290
Contactor
IEC 60617 – S00284
Other devices According to IEC 60617

– 10 – 60309-4  IEC:2006+A1:2012
7.3 Replacement:
7.3 The marking for rated current, the type reference, the nature of supply, if necessary, and
either the name or trademark of the manufacturer or the responsible vendor shall be on the
outside of the enclosure, or on the lid, if any, if the latter cannot be removed without the aid of
a tool.
These markings shall be easily discernible when the accessory is mounted and wired as in
normal use, if necessary after it has been removed from the enclosure. The marking, if any,
for the insulation voltage shall not be visible when the accessory is mounted and wired as in
normal use.
The marking for rated operating voltage, type reference, the degree of protection, and the
symbol indicating the position of the earthing contact or the means used for
interchangeability, if any, shall be on a place which is visible after installation of the
accessory, on the outside of enclosure or on the lid, if any, if the latter cannot be removed
without the aid of a tool.
With the exception of the type reference, these markings shall be easily discernible when the
accessory is mounted and wired as in normal use.
Compliance is checked by inspection.
7.4 This clause of Part 1 or Part 2 is not applicable.
7.5 Replacement:
7.5 Marking of the terminals for the supply cables
The neutral terminal, if any, shall be marked N.
The earth terminal, if any, shall be marked    or   .
The relationship between the terminals for the supply cable and load terminals/load contacts
shall be made clear, if necessary by means of a diagram or instruction.
Compliance is checked by inspection.
7.6 Replacement of the first sentence by the following text:
7.6 Marking on the outside of the enclosure shall be indelible and easily legible.
Addition:
7.101 The indication of the positions (open or closed) of the switching device shall be
unambiguous and clearly indicated.
The actuator of a mechanical switching device may be used to indicate the position of the
contacts.
For mechanical switching devices operated by means of two push-buttons, only the push-
button designated for the opening operation shall be red or marked with the symbol “O“.
The colours of other push-buttons, illuminated push-buttons and indicator lights shall be in
accordance with IEC 60073.
60309-4  IEC:2006+A1:2012 – 11 –
7.102 The marking of the type of switching device shall be on a place which is visible after
installation of the products, on the outside of enclosure or on the lid, if any, if the latter cannot
be removed without the aid of a tool.
8 Dimensions
This clause of Part 2 is applicable except as follows:
8.1 Replacement of the first 2 paragraphs starting with “Accessories shall” and finishing with
“non-interchangeability” by the following:
Accessories shall comply with the relevant standard sheets as specified below:
– accessories having rated operating voltages exceeding 50 V:
– 16/20 A Sheets 2-VIII and 2-VIIIa;
– 16/20 A and 32/30 A Sheets 2-I, 2-II, 2-IX and 2-IXa;
– 63/60 A and 125/100 A, without pilot contact Sheets 2-III and 2-IV;
– 63/60 A and 125/100 A, with pilot contact Sheets 2-IIIa and 2-IVa;
– mechanical interlock for 16 A to 125 A accessories Sheet 2-V
– accessories having rated operating voltage not exceeding 50 V:
– 16/20 A and 32/30 A Sheets 2-VIII and 2-IX.
Switched socket-outlets according to 6.1.101 with degree of protection higher than IP44 and
different from IP67 shall use socket-outlets that comply with IP66/IP67 construction as stated
in standard sheet 2-I (continuation 2) or 2-III (continuation 2) or 2-VIII (continuation 2) (see
6.1.2).
Deviations from the dimensions specified in the standard sheets may be made, but only if
they provide a technical advantage and do not adversely affect the purpose and safety of the
accessories complying with the standard sheets, especially with regard to interchangeability
and non-interchangeability.
9 Protection against electric shock
Replacement of this clause of Part 1 or Part 2 by the following:
9.1 The enclosure shall be designed so that live parts are not accessible when in normal use
and when parts which can be removed without the aid of a tool have been removed.
Compliance is checked by inspection and, if necessary, by the tests from 9.1.1 to 9.1.3.
9.1.1 The standard test finger shown in Figure 2 of IEC 60309-1 is applied with a force of 10
N ± 1 N in every possible position. An electrical indicator with a voltage not less than 40 V
and not more than 50 V is used to show contact with the relevant part.
9.1.2 For elastomeric or thermoplastic enclosures, the following test is made at an ambient
temperature of 35°C ± 2°C, the products being at this temperature.
During this test, the parts of elastomeric or thermoplastic material of the products are
subjected for 1 min to a force of 75 N, applied through the tip of a straight unjointed test finger
of the same dimensions as the standard test finger. This finger, with an electrical indicator as
described above, is applied to all places where yielding of the insulating material could impair
the safety of the product.
– 12 – 60309-4  IEC:2006+A1:2012
During this test, the product shall not deform to such an extent that live parts become
accessible.
+0,1
9.1.3 The test probe D of IEC 61032 is applied with a force of 1 N.
This test does not apply to the components fitted to the product.
The protection is satisfactory if the wire cannot enter the enclosure, or if it enters, it does not
touch live parts inside the enclosure.
The test wire is provided with an electrical indicator, with a voltage not less than 40 V and not
more than 50 V, to show contact with relevant part.
9.2 Parts providing protection against electric shock shall have adequate mechanical
strength and shall be reliably secured by means of screws or in a similar reliable manner so
that they will not loosen in normal use.
Compliance is checked by inspection and by the tests of Clauses 24 and 25.
9.3 Knobs, operating levers, push-buttons, rockers and the like, for operating switches in
switched socket-outlets or connectors shall be of insulating material, unless their accessible
metal parts are separated from the metal parts of the mechanism by double insulation or
reinforced insulation, or they are reliably connected to earth.
Compliance is checked by inspection and by the tests of Clauses 19 and 22.
10 Provision for earthing
This clause of Part 1 or Part 2 is applicable except as follows:
10.1 Replacement of the first paragraph by the following:
Products with earthing contact shall be provided with an earthing terminal. Metal-clad fixed
products with an internal earthing terminal can, in addition, be provided with an external
earthing terminal, which, except for flush type products, shall be visible from the outside.
The earthing terminal of the socket-outlet or connector may be used provided it is easily
accessible.
11 Terminals
This clause of Part 1 or Part 2 is applicable.
12 Interlocks, switches and their components
Replacement of this clause of Part 1 or Part 2 by the following:
12.1 Switched socket-outlets or connectors with interlocks shall be so constructed that a
plug or appliance inlet cannot be completely withdrawn from the socket-outlet or connector
while the contacts of that socket-outlet or connector are live, and the contacts of the socket-
outlet or connector cannot be made live until a plug or appliance inlet is in proper
engagement. The contacts shall not open or close on load.

60309-4  IEC:2006+A1:2012 – 13 –
A female pilot contact in a switched socket-outlet or connector (interlocked or non-interlocked)
may be live when not engaged with a male pilot contact if the female contact is part of a SELV
circuit or if it is not accessible with the standard test finger according to Figure 2.
NOTE SELV is defined in IEC 60364-4-41 .
Socket-outlets and connectors shall be so designed that, after engagement with a
complementary accessory, the interlock operates correctly.
The operation of an interlock shall not be impaired by normal wear of the portion of the plug
used for interlocking.
Compliance is checked by carrying out the tests of 12.1.1 or 12.1.2 as applicable after the
test of Clause 21.
12.1.1 Switched socket-outlets or connectors with interlock but without latching function
(electrical interlock) shall be so constructed that
– the time interval between the opening of the contacts of the control switching device and
the opening of the contacts of the main poles shall be sufficient to ensure that the
mechanical switching device interrupts the current before the contacts of the plug are
disconnected from the contacts of the socket-outlet;
– during the closing operation, the contacts of the control switching device shall close after
or simultaneously with the contacts of the main poles.
Compliance is checked by the following test:
For products provided with an actuator, an attempt shall be made, without the plug inserted,
to close the switching device by applying a force according to 24.101. The switching device
contacts shall not close.
This is checked by a continuity test made between the supply terminals and the contact
assembly of the socket-outlet.
The time interval is checked by measuring the time interval between the instant of opening of
the contacts of the control switching device and the instant of opening of the contact of the
mechanical switching device, under no-load conditions.
For 60/63 A and 100/125 A products complying to Part 2 where the control switching device
depends on pilot pin and pilot contact-tube, the time interval shall not be greater than 35 ms.
NOTE The time interval of 35 ms is the ratio between the distances given in the standard sheets, in the worst
condition, and the separation speed given in Clauses 20 and 21.
12.1.2 Switched socket-outlets and connector with interlock with latching devices locking the
plug or appliance inlet into the socket-outlet or connector (mechanical interlock) shall be so
constructed that the interlock is linked with the operation of a switching device so that the
plug or appliance inlet can neither be inserted nor withdrawn from the socket-outlet or
connector while the contacts of the socket-outlet or connector are live and the contacts of the
socket-outlet or connector cannot be made live until a plug is almost completely in
engagement.
Compliance is checked by inspection, by a manual test and by the following test:
—————————
IEC 60364-4-41, Low-voltage electrical installations - Part 4-41: Protection for safety - Protection against electric
shock
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Products with interlock and latching devices, which hold the plug into the socket-outlet or
connector, are subjected to the following test:
Without the plug inserted an attempt shall be made to close the switching device by applying
a force according to 24.101. The switching device contacts shall not close.
This is checked by a continuity test made between the supply terminals and the contact
assembly of the socket-outlet.
The switched socket-outlet or connector with interlock is fixed to the support of an apparatus
as shown in Figure 102 so that the axis of separation is vertical and the movement of the plug
is downwards. With the latching devices holding the plug into the socket-outlet or connector in
the engaged position, an axial pull is applied to an appropriate plug inserted in the switched
socket-outlet or connector with interlock.The test plug, according to the relevant standard
sheets, shall have finely ground contacts of hardened steel, having a surface roughness not
exceeding 0,8 µm over their active length and spaced at the nominal distances, with a
tolerance of ±0,05 mm.
The dimension of the plug contacts or the distance between contact surfaces for other types
of plug contacts shall be in accordance with the minimum dimension(s) given in the relevant
+0,01
standard sheets, with a tolerance of mm.
The plug contacts are wiped free from grease before test.
The test plug is inserted into and withdrawn from the socket-outlet or connector ten times. It is
then again inserted, a mass being attached to it by means of a suitable clamp. The total mass
of the plug, the clamp, the carrier, the principal and the supplementary weight shall exert a
pull force according to Table 101. The supplementary weight shall be such that it exerts a
force equal to one-tenth of the withdrawal force. The retaining means, if any, shall be opened.
The principal weight is hung without jolting on the test plug, and the supplementary weight is
allowed to fall from a height of 5 cm onto the principal weight.
Table 101 − Withdrawal force with respect to ratings
Rated current Withdrawal force
A
N
Series I Series II Other ratings
16 20 165
32 30 165
63 60 300
125 100 440
250 200 160 660
315 300
630 600
60309-4  IEC:2006+A1:2012 – 15 –
During the test the plug shall not come out of the socket-outlet or connector and the latching
devices holding the plug in the socket-outlet or connector shall remain in locked position.
During the test the electrical continuity shall be maintained.
After the test, the switched socket-outlet or connector with interlock shall show no damage or
deformation which may impair the function of the product.
Compliance is checked by inspection and test.
12.2 Switching devices shall have at least the same number of poles as the socket-outlet.
NOTE Switching of the neutral depends on National regulations.
For this purpose, the earthing contact is not considered as a pole and shall not be switched.
Compliance is checked by inspection.
12.3 Switching devices shall have the following characteristics:
12.3.1 Associated switching devices
12.3.1.1 Switch and switch-disconnector
Switches and switch-disconnectors for switched socket-outlets or connectors shall comply
with IEC 60947-3 and,
– for a.c. application, shall have a rated current, at a utilization category of at least AC-22A,
not less than the rated current of the associated socket-outlet or connector;
– for d.c. application, shall have a rated current, at a utilization category of at least DC-21A,
not less than the rated current of the associated socket-outlet or connector.
Compliance is checked by inspection, by measurement and by tests.
12.3.1.2 Contactor
Contactors for switched socket-outlets or connectors shall comply with IEC 60947-4-1 and,
– for a.c. application, shall have a rated current, at a utilization category of at least AC-2,
not less than the rated current of the associated socket-outlet or connector;
– for d.c. application, shall have a rated current, at a utilization category of at least DC-3,
not less than the rated current of the associated socket-outlet or connector.
Compliance is checked by inspection, by measurement and by tests.
12.3.1.3 Other devices
Under consideration.
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12.3.2 Integral switching device
Integral switching devices shall comply with IEC 60947-3 as far as it is applicable and,
– for a.c. application, shall have a rated current, at a utilization category of at least AC-22A,
not less that the rated current of the associated socket-outlet or connector;
– for d.c. application, shall have a rated current, at a utilization category of at least DC-21A,
not less than the rated current of the associated socket-outlet or connector.
12.4 Control circuit devices and switching elements, if any, used in the control circuit of an
electrically interlocked socket-outlet or connector shall comply with IEC 60947-5-1 or
IEC 61058-1 and they shall have ratings suitable for the load to be controlled.
Control switching devices according to IEC 61058-1 shall be classified with at least
6000 cycles.
Compliance is checked by inspection, by measurement and by tests.
12.5 Switching devices according 12.3 shall comply with Clause 29, unless already tested to
the relevant standard for short-circuit current withstand of at least 10 kA.
Compliance is checked by inspection, by measurement and by tests.
12.6 Switching devices suitable for isolation shall provide in the open position an isolation
distance in accordance with the requirements of IEC 60947-1, necessary to satisfy the
isolating function (see 2.104).
For switching devices suitable for isolation, indication of the position of the main contacts
shall be provided by one of the following means:
– the position of the actuator, or
– a separate mechanical indicator.
This indication shall be visible when the product is in its normal working position.
When the operating means of the mechanical switching device is used to indicate the open or
closed positions, the mechanical strength of the actuating mechanism and the reliability of the
indication of the open position shall be adequate.
Compliance is checked by inspection and by the test of 24.101.
12.7 Locking means (for the mechanical switching device)
Means may be provided by the manufacturer to enable the mechanical switching device to be
locked in the open position, e.g. for padlock(s).
NOTE Locking in the closed position is permitted for particular applications.
If locking means are provided, the locking means shall be designed in such a way that they
cannot be removed with the appropriate padlock(s) installed without the aid of a tool.
When the mechanical switching device is locked by even a single padlock, it shall not be
possible by operating the actuator, to reduce the clearance between open contacts to the
extent that it no longer complies with the requirements for clearances of IEC 60947-1.
Alternatively, the design may provide lockable means to prevent access to the operating
means of the mechanical switching device.

60309-4  IEC:2006+A1:2012 – 17 –
Compliance is checked by inspection and by the test of 24.102.
12.8 Pilot contacts
Pilot contacts and auxiliary circuits used for interlocks shall make after the neutral and
phase(s) are made.
Pilot contacts and auxiliary circuits used for interlocks shall break before the phase(s) and
neutral are broken.
Compliance is checked by inspection and by test of 12.1.1.
13 Resistance to ageing of rubber and thermoplastic material
This clause of Part 1 or Part 2 is applicable.
14 General construction
This clause of Part 1 or Part 2 is applicable.
14.101 Accessories with a rated current above 250 A shall be provided with an interlock.
15 Construction of socket-outlets
This clause of Part 1 or Part 2 is applicable.
16 Construction of plugs and connectors
This clause of Part 1 or Part 2 is applicable.
17 Construction of appliance inlets
This clause of Part 1 or Part 2 is not applicable.
18 Degrees of protection
This clause of Part 1 or Part 2 is applicable.
19 Insulation resistance and dielectric strength
This clause of Part 1 or Part 2 is applicable, except as follows:
19.2.1 Addition, before the note, of the following text:
For switched socket-outlets or connectors, the test is carried out with the switch in the ON
position.
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