EN IEC 60974-1:2018

SLOVENSKI STANDARD
01-december-2018
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SIST EN 60974-1:2012
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Arc welding equipment - Part 1: Welding power sources (IEC 60974-1:2017)
Lichtbogenschweißeinrichtungen - Teil 1: Schweißstromquellen (IEC 60974-1:2017)
Matériel de soudage à l'arc - Partie 1: Sources de courant de soudage (IEC 60974-
1:2017)
Ta slovenski standard je istoveten z: EN IEC 60974-1:2018
ICS:
25.160.30 Varilna oprema Welding equipment
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 60974-1

NORME EUROPÉENNE
EUROPÄISCHE NORM
September 2018
ICS 25.160 Supersedes EN 60974-1:2012
English Version
Arc welding equipment - Part 1: Welding power sources
(IEC 60974-1:2017)
Matériel de soudage à l'arc - Partie 1: Sources de courant Lichtbogenschweißeinrichtungen - Teil 1:
de soudage Schweißstromquellen
(IEC 60974-1:2017) (IEC 60974-1:2017)
This European Standard was approved by CENELEC on 2018-07-15. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden,
Switzerland, Turkey and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2018 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 60974-1:2018 E

European foreword
The text of document 26/610/FDIS, future edition 5 of IEC 60974-1, prepared by IEC/TC 26 "Electric
welding" was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as
The following dates are fixed:
• latest date by which the document has to be implemented at national (dop) 2019-03-28
level by publication of an identical national standard or by endorsement
• latest date by which the national standards conflicting with the (dow) 2021-09-28
document have to be withdrawn
This document supersedes EN 60974-1:2012.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC shall not be held responsible for identifying any or all such patent rights.
Endorsement notice
The text of the International Standard IEC 60974-1:2017 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards
indicated:
IEC 60038:2009 NOTE Harmonized as EN 60038:2011 (modified)
IEC 60085 NOTE Harmonized as EN 60085
IEC 60204-1 NOTE Harmonized as EN 60204-1
IEC 60309-1 NOTE Harmonized as EN 60309-1
IEC 60335-2-29 NOTE Harmonized as EN 60335-2-29
IEC 60384-14 NOTE Harmonized as EN 60384-14
IEC 60950-1 NOTE Harmonized as EN 60950-1
IEC 60974-3 NOTE Harmonized as EN 60974-3
IEC 60974-4 NOTE Harmonized as EN 60974-4
IEC 60974-6 NOTE Harmonized as EN 60974-6
IEC 60974-9 NOTE Harmonized as EN IEC 60974-9
IEC 60974-10 NOTE Harmonized as EN 60974-10
IEC 60974-12 NOTE Harmonized as EN 60974-12
IEC 61032:1997 NOTE Harmonized as EN 61032:1998 (not modified)
IEC 61558-1 NOTE Harmonized as EN 61558-1
IEC 62281 NOTE Harmonized as EN 62281
ISO 13732-1 NOTE Harmonized as EN ISO 13732-1

Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
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.
NOTE 1  Where an International Publication has been modified by common modifications, indicated by (mod), the relevant
EN/HD applies.
NOTE 2  Up-to-date information on the latest versions of the European Standards listed in this annex is available here:
www.cenelec.eu.
Publication Year Title EN/HD Year
IEC 60050-151 -  International Electrotechnical Vocabulary - - -
Part 151: Electrical and magnetic devices
IEC 60050-851 -  International Electrotechnical Vocabulary - - -
Part 851: Electric welding
IEC 60245-6 -  Rubber insulated cables - Rated voltages - -
up to and including 450/750 V -- Part 6: Arc
welding electrode cables
IEC 60417 -  Graphical symbols for use on equipment. HD 243 S12 -
Index, survey and compilation of the single
sheets.
Basic and safety principles for man-
IEC 60445 -  - -
machine interface, marking and
identification – Identification of equipment
terminals, conductor terminations and
conductors
IEC 60529 -  Degrees of protection provided by - -
enclosures (IP Code)
IEC 60664-1 2007 Insulation coordination for equipment EN 60664-1 2007
within low-voltage systems - Part 1:
Principles, requirements and tests
IEC 60664-3 -  Insulation coordination for equipment EN 60664-3 -
within low-voltage systems - Part 3: Use of
coating, potting or moulding for protection
against pollution
IEC 60695-11-10 -  Fire hazard testing -- Part 11-10: Test EN 60695-11-10 -
flames - 50 W horizontal and vertical flame
test methods
IEC 60974-7 -  Arc welding equipment -- Part 7:Torches EN 60974-7 -
IEC 61140 -  Protection against electric shock - EN 61140 -
Common aspects for installation and
equipment
IEC 61558-2-4 -  Safety of transformers, reactors, power EN 61558-2-4 -
supply units and similar products for supply
voltages up to 1 100 V - Part 2-4: Particular
requirements and tests for isolating
transformers and power supply units
incorporating isolating transformers
IEC 61558-2-6 -  Safety of transformers, reactors, power EN 61558-2-6 -
supply units and similar products for supply
voltages up to 1 100 V -- Part 2-6:
Particular requirements and tests for safety
isolating transformers and power supply
units incorporating safety isolating
transformers
IEC 62133-1 -  Secondary cells and batteries containing EN 62133-1 -
alkaline or other non-acid electrolytes -
Safety requirements for portable sealed
secondary cells, and for batteries made
from them, for use in portable applications
- Part 1: Nickel systems
IEC 62133-2 -  Secondary cells and batteries containing EN 62133-2 -
alkaline or other non-acid electrolytes -
Safety requirements for portable sealed
secondary lithium cells, and for batteries
made from them, for use in portable
applications - Part 2: Lithium systems
ISO 7010 2011 Graphical symbols - Safety colours and EN ISO 7010 2012
safety signs - Registered safety signs

IEC 60974-1 ®
Edition 5.0 2017-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Arc welding equipment –
Part 1: Welding power sources
Matériel de soudage à l’arc –
Partie 1: Sources de courant de soudage

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 25.160.30 ISBN 978-2-8322-3854-7

– 2 – IEC 60974-1:2017 © IEC 2017
CONTENTS
FOREWORD . 9
1 Scope . 11
2 Normative references . 11
3 Terms and definitions . 12
3.1 General terms . 12
3.2 Terms related to battery systems . 21
4 Environmental conditions . 24
5 Tests . 25
5.1 Test conditions . 25
5.2 Measuring instruments . 25
5.3 Conformity of components . 25
5.4 Type tests . 26
5.5 Routine tests. 26
6 Protection against electric shock . 27
6.1 Insulation . 27
6.1.1 General . 27
6.1.2 Clearances . 28
6.1.3 Creepage distances . 30
6.1.4 Insulation resistance . 32
6.1.5 Dielectric strength . 32
6.2 Protection against electric shock in normal service (direct contact) . 34
6.2.1 Protection provided by the enclosure . 34
6.2.2 Capacitors . 34
6.2.3 Automatic discharge of supply circuit capacitors . 35
6.2.4 Isolation of the welding circuit . 35
6.2.5 Welding circuit touch current . 35
6.2.6 Touch current in normal condition . 36
6.3 Protection against electric shock in case of a fault condition (indirect contact)
............................................................................................................................. 37
6.3.1 Protective provisions . 37
6.3.2 Isolation between windings of the supply circuit and the welding circuit . 37
6.3.3 Internal conductors and connections . 37
6.3.4 Additional requirements for plasma cutting systems . 38
6.3.5 Movable coils and cores . 38
6.3.6 Touch current in fault condition . 38
7 Thermal requirements . 39
7.1 Heating test . 39
7.1.1 Test conditions . 39
7.1.2 Tolerances of the test parameters . 39
7.1.3 Duration of test . 40
7.2 Temperature measurement . 40
7.2.1 Measurement conditions . 40
7.2.2 Surface temperature sensor . 40
7.2.3 Resistance . 40
7.2.4 Embedded temperature sensor . 41
7.2.5 Determination of the ambient air temperature . 41

IEC 60974-1:2017 © IEC 2017 – 3 –
7.2.6 Recording of temperatures . 41
7.3 Limits of temperature rise . 41
7.3.1 Windings, commutators and slip-rings . 41
7.3.2 External surfaces . 42
7.3.3 Other components . 43
7.4 Loading test . 43
7.5 Commutators and slip-rings . 44
8 Thermal protection. 44
8.1 General requirements . 44
8.2 Construction . 44
8.3 Location . 44
8.4 Operating capacity . 44
8.5 Operation . 45
8.6 Resetting . 45
8.7 Indication . 45
9 Abnormal operation . 45
9.1 General requirements . 45
9.2 Stalled fan test . 46
9.3 Short circuit test . 46
9.4 Overload test . 47
10 Connection to the supply network . 47
10.1 Supply voltage . 47
10.2 Multi-supply voltage . 47
10.3 Means of connection to the supply circuit . 47
10.4 Marking of terminals . 48
10.5 Protective circuit . 48
10.5.1 Continuity requirement . 48
10.5.2 Type test . 49
10.5.3 Routine test . 49
10.6 Cable anchorage . 50
10.7 Inlet openings . 51
10.8 Supply circuit on/off switching device . 51
10.9 Supply cables . 52
10.10 Supply coupling device (attachment plug) . 52
11 Output . 53
11.1 Rated no-load voltage . 53
11.1.1 Rated no-load voltage for use in environments with increased risk of
electric shock . 53
11.1.2 Rated no-load voltage for use in environments without increased risk of
electric shock . 53
11.1.3 Rated no-load voltage for the use with mechanically held torches with
increased protection for the operator . 53
11.1.4 Rated no-load voltage for special processes for example plasma cutting . 53
11.1.5 Additional requirements . 54
11.1.6 Measuring circuits . 55
11.2 Type test values of the conventional load voltage . 56
11.2.1 Manual metal arc welding with covered electrodes . 56
11.2.2 Tungsten inert gas . 56
11.2.3 Metal inert/active gas and flux cored arc welding . 56

– 4 – IEC 60974-1:2017 © IEC 2017
11.2.4 Submerged arc welding . 56
11.2.5 Plasma cutting . 56
11.2.6 Plasma welding . 56
11.2.7 Plasma gouging . 56
11.2.8 Additional requirements . 56
11.3 Mechanical switching devices used to adjust output . 57
11.4 Welding circuit connections . 57
11.4.1 Protection against unintentional contact . 57
11.4.2 Location of coupling devices . 57
11.4.3 Outlet openings . 57
11.4.4 Three-phase multi-operator welding transformer . 57
11.4.5 Marking . 58
11.4.6 Connections for plasma cutting torches . 58
11.5 Power supply to external devices connected to the welding circuit . 58
11.6 Auxiliary power supply . 58
11.7 Welding cables . 59
12 Control circuits . 59
12.1 General requirement . 59
12.2 Isolation of control circuits . 59
12.3 Working voltages of remote control circuits . 59
13 Hazard reducing device . 60
13.1 General requirements . 60
13.2 Types of hazard reducing devices . 60
13.2.1 Voltage reducing device . 60
13.2.2 Switching device for AC to DC . 60
13.3 Requirements for hazard reducing devices . 60
13.3.1 Disabling the hazard reducing device . 60
13.3.2 Interference with operation of a hazard reducing device . 61
13.3.3 Indication of satisfactory operation . 61
13.3.4 Fail to a safe condition . 61
14 Mechanical provisions . 61
14.1 General requirements . 61
14.2 Enclosure . 61
14.2.1 Enclosure materials . 61
14.2.2 Enclosure strength . 62
14.3 Handling means . 62
14.3.1 Mechanised handling . 62
14.3.2 Manual handling . 62
14.4 Drop withstand . 63
14.5 Tilting stability . 63
15 Rating plate . 63
15.1 General requirements . 63
15.2 Description . 64
15.3 Contents . 65
15.4 Tolerances . 68
15.5 Direction of rotation . 68
16 Adjustment of the output . 68
16.1 Type of adjustment . 68

IEC 60974-1:2017 © IEC 2017 – 5 –
16.2 Marking of the adjusting device . 69
16.3 Indication of current or voltage control . 69
17 Instructions and markings . 70
17.1 Instructions . 70
17.2 Markings . 71
Annex A (informative) Nominal voltages of supply networks . 72
Annex B (informative) Example of a combined dielectric test . 73
Annex C (normative) Unbalanced load in case of AC tungsten inert-gas welding power
sources . 74
C.1 General . 74
C.2 Unbalanced load . 74
C.3 Example for an unbalanced load . 75
Annex D (informative) Extrapolation of temperature to time of shutdown . 76
Annex E (normative) Construction of supply circuit terminals . 77
E.1 Size of terminals . 77
E.2 Connections at the terminals . 77
E.3 Construction of the terminals . 78
E.4 Fixing of the terminals . 78
Annex F (informative) Cross-reference to non-SI units . 79
Annex G (informative) Suitability of supply network for the measurement of the true
r.m.s. value of the supply current . 80
Annex H (informative) Plotting of static characteristics . 81
H.1 General . 81
H.2 Method . 81
H.3 Analysis of the results . 81
Annex I (normative) Test methods for a 10 Nm impact . 82
I.1 Pendulum impact hammer . 82
I.2 Free fall spherical steel weight . 83
Annex J (normative) Thickness of sheet metal for enclosures . 84
Annex K (informative) Examples of rating plates . 87
Annex L (informative) Graphical symbols for arc welding equipment . 94
L.1 General . 94
L.2 Use of symbols . 94
L.2.1 General . 94
L.2.2 Selection of symbols . 94
L.2.3 Size of symbols . 94
L.2.4 Use of colour . 94
L.3 Symbols . 95
L.3.1 General . 95
L.3.2 Letter symbols . 95
L.3.3 Graphical symbols . 96
L.4 Examples of combinations of symbols . 116
L.5 Examples of control panels . 118
Annex M (informative) Efficiency and idle state power measurement . 121
M.1 Measuring efficiency . 121
M.2 Measuring idle state power . 121
Annex N (normative) Touch current measurement in fault condition . 123

– 6 – IEC 60974-1:2017 © IEC 2017
Annex O (normative) Battery-powered welding power sources . 128
O.1 General . 128
O.4 Environmental conditions . 129
O.5 Tests . 129
O.5.1 Test conditions . 129
O.5.3 Conformity of components . 130
O.6 Protection against electric shock . 131
O.6.1 Insulation . 131
O.6.2 Protection against electric shock in normal service . 132
O.7 Thermal requirements . 133
O.7.1 Heating test . 133
O.7.2 Temperature measurement . 134
O.7.4 Loading test . 134
O.7.201 Normal charging of lithium-ion systems . 134
O.8 Thermal protection . 135
O.8.1 General requirements . 135
O.8.4 Operating capacity . 135
O.9 Abnormal operation . 135
O.9.1 General requirements . 135
O.9.2 Stalled fan test . 136
O.9.3 Short circuit test . 136
O.9.4 Overload test . 136
O.9.201 Welding power source – abnormal conditions . 136
O.9.202 Welding circuit components – abnormal conditions . 137
O.9.203 Lithium-ion charging systems − abnormal conditions . 137
O.9.204 Lithium-ion battery short circuit . 138
O.9.205 Batteries other than lithium-ion – overcharging . 139
O.9.206 Battery pack disconnection . 139
O.9.207 General purpose batteries . 139
O.10 Connection to the supply network . 139
O.10.5 Protective circuit . 140
O.10.8 Supply circuit on/off switching device . 140
O.14 Mechanical provisions . 141
O.14.1 General requirements . 141
O.14.2 Enclosure . 141
O.14.4 Drop withstand . 141
O.15 Rating plate . 142
O.15.3 Contents . 142
O.17 Instructions and markings . 144
O.17.1 Instructions . 144
O.17.2 Markings . 145
Bibliography . 146

Figure 1 – Example of insulation configuration for Class I equipment . 28
Figure 2 – Measurement of welding circuit touch current . 36
Figure 3 – Measurement of touch current in normal condition . 36
Figure 4 – Measurement of r.m.s. values . 55
Figure 5 – Measurement of peak values . 55

IEC 60974-1:2017 © IEC 2017 – 7 –
Figure 6 – Principle of the rating plate . 64
Figure B.1 – Combined high-voltage transformers . 73
Figure C.1 – Voltage and current during AC tungsten inert-gas welding . 74
Figure C.2 – Unbalanced voltage during AC tungsten inert-gas welding . 75
Figure C.3 – AC welding power source with unbalanced load . 75
Figure I.1 – Test set-up . 82
Figure K.1 – Single-phase transformer . 87
Figure K.2 – Three-phase rotating frequency converter . 88
Figure K.3 – Subdivided rating plate: single-/three-phase transformer rectifier . 89
Figure K.4 – Engine-generator-rectifier . 90
Figure K.5 – Single-/three-phase inverter type . 91
Figure K.6 – Battery powered welding power source with integral battery . 92
Figure K.7 – Battery powered welding power source with detachable / separable
battery . 93
Figure L.1 – Input voltage power switch . 119
Figure L.2 – Arc force control potentiometer . 119
Figure L.3 – Remote receptacle and selector switches . 119
Figure L.4 – Terminals with inductance selector for MIG/MAG welding. 119
Figure L.5 – Process switch (MMA, TIG, MIG) . 120
Figure L.6 – Selector switch on AC/DC equipment . 120
Figure L.7 – Panel indicator lights (overheat, fault, arc striking, output voltage) . 120
Figure L.8 – Setting pulsing parameters using digital display . 120
Figure N.1 – Measuring network for weighted touch current . 123
Figure N.2 – Diagram for touch current measurement on fault condition at operating
temperature for single-phase connection of appliances other than those of class II . 125
Figure N.3 – Diagram for touch current measurement on fault condition for three-phase
four-wire system connection of appliances other than those of class II . 127
Figure O.1 – Marking of battery voltage class B electric components . 145

Table 1 – Minimum clearances for overvoltage category III . 29
Table 2 – Minimum creepage distances . 31
Table 3 – Insulation resistance . 32
Table 4 – Dielectric test voltages . 33
Table 5 – Minimum distance through insulation . 37
Table 6 – Temperature limits for windings, commutators and slip-rings . 42
Table 7 – Temperature limits for external surfaces . 43
Table 8 – Cross-section of the output short-circuit conductor . 46
Table 9 – Current and time requirements for protective circuits . 49
Table 10 – Minimum cross-sectional area of the external protective copper conductor . 49
Table 11 – Verification of continuity of the protective circuit . 50
Table 12 – Pull. 51
Table 13 – Summary of allowable rated no-load voltages . 54
Table 14 – Hazard reducing device requirements . 60

– 8 – IEC 60974-1:2017 © IEC 2017
Table E.1 – Range of conductor dimensions to be accepted by the supply circuit
terminals . 77
Table F.1 – Cross-reference for mm to American wire gauge (AWG) . 79
Table I.1 – Angle of rotation θ to obtain 10 Nm impact . 82
Table I.2 – Mass of the free fall weight and height of the free fall . 83
Table J.1 – Minimum thickness of sheet metal for steel enclosures . 85
Table J.2 – Minimum thickness of sheet metal for enclosures of aluminium, brass or
copper . 86
Table L.1 – Letters used as symbols . 95

IEC 60974-1:2017 © IEC 2017 – 9 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
ARC WELDING EQUIPMENT –
Part 1: Welding power sources
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject d
...