IEC 60204-1:2016

Safety of machinery - Electrical equipment of machines - Part 1: General requirements

IEC 60204-1:2016 applies to electrical, electronic and programmable electronic equipment and systems to machines not portable by hand while working, including a group of machines working together in a co-ordinated manner. The equipment covered by this part of IEC 60204 commences at the point of connection of the supply to the electrical equipment of the machine. This sixth edition cancels and replaces the fifth edition published in 2005. It constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition:
- added requirements to address applications involving power drive systems (PDS);
- revised electromagnetic compatibility (EMC) requirements;
- clarified overcurrent protection requirements;
- requirements for determination of the short circuit current rating of the electrical equipment;
- revised protective bonding requirements and terminology;
- reorganization and revision to Clause 9, including requirements pertaining to safe torque off of PDS, emergency stop, and control circuit protection;
- revised symbols for actuators of control devices;
- revised technical documentation requirements;
- general updating to current special national conditions, normative standards, and bibliographical references.

Sécurité des machines - Équipement électrique des machines - Partie 1: Exigences générales

L'IEC 60204-1:2016 s'applique aux équipements et systèmes électriques, électroniques et électroniques programmables des machines non portables à la main en fonctionnement y compris un groupe de machines fonctionnant ensemble d'une manière coordonnée. L'équipement couvert par la présente partie de l'IEC 60204 commence au point de connexion de l'alimentation à l'équipement électrique de la machine. Cette sixième édition annule et remplace la cinquième édition parue en 2005. Cette édition constitue une révision technique. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente:
- exigences supplémentaires pour traiter des applications impliquant des systèmes d'entraînements électriques de puissance (PDS);
- exigences révisées concernant la compatibilité électromagnétique (CEM);
- clarification des exigences de protection contre les surintensités;
- exigences pour la détermination des caractéristiques du courant de court-circuit de l'équipement électrique;
- révision des exigences de liaisons de protection et la terminologie;
- réorganisation et révision à l'Article 9, notamment les exigences relatives à la suppression sûre du couple du PDS, à l'arrêt d'urgence, et à la protection du circuit de commande;
- révision des symboles pour les organes de commande des appareils de commande;
- révision des exigences sur la documentation technique;
- mise à jour générale des conditions nationales particulières, des normes et des références bibliographiques.

General Information

• Status: Published
• Publication Date: 14-Sep-2021
• ICS: 13.110 - Safety of machinery
• ICS: 29.020 - Electrical engineering in general
• Technical Committee: TC 44 - Safety of machinery - Electrotechnical aspects
• Drafting Committee: MT 60204-1 - TC 44/MT 60204-1
• Current Stage: PPUB - Publication issued
• Start Date: 13-Oct-2016
• Completion Date: 31-Aug-2016

Relations

• Amended By: IEC 60204-1:2016/AMD1:2021 - Amendment 1 - Safety of machinery - Electrical equipment of machines - Part 1: General requirements
• Effective Date: 05-Sep-2023
• Revises: IEC 60204-1:2005 - Safety of machinery - Electrical equipment of machines - Part 1: General requirements
• Effective Date: 05-Sep-2023
• Revises: IEC 60204-1:2005/AMD1:2008 - Amendment 1 - Safety of machinery - Electrical equipment of machines - Part 1: General requirements
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 60204-1 ®
Edition 6.0 2016-10
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Safety of machinery – Electrical equipment of machines –
Part 1: General requirements
All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
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IEC 60204-1 ®
Edition 6.0 2016-10
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Safety of machinery – Electrical equipment of machines –

Part 1: General requirements
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 13.110; 29.020 ISBN 978-2-8322-3696-3

– 2 – IEC 60204-1:2016 RLV © IEC 2016
CONTENTS
FOREWORD . 10
INTRODUCTION . 13
1 Scope . 15
2 Normative references . 16
3 Terms, definitions and abbreviated terms . 19
3.1 Terms and definitions. 19
3.2 Abbreviated terms . 28
4 General requirements . 28
4.1 General . 28
4.2 Selection of equipment . 29
4.2.1 General . 29
4.2.2 Electrical equipment in compliance with the IEC 60439 series
Switchgear . 30
4.3 Electrical supply. 30
4.3.1 General . 30
4.3.2 AC supplies . 30
4.3.3 DC supplies . 30
4.3.4 Special supply systems . 31
4.4 Physical environment and operating conditions . 31
4.4.1 General . 31
4.4.2 Electromagnetic compatibility (EMC) . 31
4.4.3 Ambient air temperature . 32
4.4.4 Humidity . 32
4.4.5 Altitude . 32
4.4.6 Contaminants . 33
4.4.7 Ionizing and non-ionizing radiation . 33
4.4.8 Vibration, shock, and bump . 33
4.5 Transportation and storage . 33
4.6 Provisions for handling . 33
4.7 Installation .
5 Incoming supply conductor terminations and devices for disconnecting and
switching off . 33
5.1 Incoming supply conductor terminations. 33
5.2 Terminal for connection to of the external protective earthing system
conductor . 34
5.3 Supply disconnecting (isolating) device . 34
5.3.1 General . 34
5.3.2 Type . 35
5.3.3 Requirements . 35
5.3.4 Operating means of the supply disconnecting device . 36
5.3.5 Excepted circuits . 37
5.4 Devices for switching off removal of power for prevention of unexpected
start-up . 37
5.5 Devices for disconnecting isolating electrical equipment . 38
5.6 Protection against unauthorized, inadvertent and/or mistaken connection . 39
6 Protection against electric shock . 39

6.1 General . 39
6.2 Basic protection against direct contact . 39
6.2.1 General . 39
6.2.2 Protection by enclosures . 40
6.2.3 Protection by insulation of live parts . 41
6.2.4 Protection against residual voltages . 41
6.2.5 Protection by barriers . 41
6.2.6 Protection by placing out of reach or protection by obstacles . 41
6.3 Fault protection against direct contact . 42
6.3.1 General . 42
6.3.2 Prevention of the occurrence of a touch voltage . 42
6.3.3 Protection by automatic disconnection of supply . 42
6.4 Protection by the use of PELV . 43
6.4.1 General requirements . 43
6.4.2 Sources for PELV . 44
7 Protection of equipment . 44
7.1 General . 44
7.2 Overcurrent protection . 45
7.2.1 General . 45
7.2.2 Supply conductors . 45
7.2.3 Power circuits . 45
7.2.4 Control circuits . 45
7.2.5 Socket outlets and their associated conductors . 46
7.2.6 Lighting circuits . 46
7.2.7 Transformers . 46
7.2.8 Location of overcurrent protective devices . 46
7.2.9 Overcurrent protective devices . 46
7.2.10 Rating and setting of overcurrent protective devices . 47
7.3 Protection of motors against overheating . 47
7.3.1 General . 47
7.3.2 Overload protection . 47
7.3.3 Over-temperature protection . 48
7.3.4 Current limiting protection .
7.4 Protection against abnormal temperature protection . 48
7.5 Protection against the effects of supply interruption or voltage reduction and
subsequent restoration . 48
7.6 Motor overspeed protection. 49
7.7 Additional earth fault/residual current protection . 49
7.8 Phase sequence protection . 49
7.9 Protection against overvoltages due to lightning and to switching surges . 49
7.10 Short-circuit current rating . 50
8 Equipotential bonding . 50
8.1 General . 50
8.2 Protective bonding circuit . 53
8.2.1 General . 53
8.2.2 Protective conductors . 54
8.2.3 Continuity of the protective bonding circuit . 55
8.2.4 Exclusion of switching devices from the protective bonding circuit .
8.2.4 Protective conductor connecting points . 56

– 4 – IEC 60204-1:2016 RLV © IEC 2016
8.2.5 Parts that need not to be connected to the protective bonding circuit .
8.2.5 Mobile machines . 56
8.2.6 Additional protective bonding requirements for electrical equipment
having earth leakage currents higher than 10 mA a.c. or d.c. . 56
8.3 Measures to limit restrict the effects of high leakage current . 57
8.4 Functional bonding . 57
9 Control circuits and control functions . 58
9.1 Control circuits . 58
9.1.1 Control circuit supply . 58
9.1.2 Control circuit voltages . 58
9.1.3 Protection . 58
9.2 Control functions . 58
9.2.1 Start functions General . 58
9.2.2 Categories of stop functions . 59
9.2.3 Operation . 59
9.2.4 Cableless control system (CCS) . 63
9.2.6 Other control functions .
9.3 Protective interlocks . 66
9.3.1 Reclosing or resetting of an interlocking safeguard . 66
9.3.2 Exceeding operating limits . 66
9.3.3 Operation of auxiliary functions . 66
9.3.4 Interlocks between different operations and for contrary motions . 66
9.3.5 Reverse current braking . 66
9.3.6 Suspension of safety functions and/or protective measures . 66
9.4 Control functions in the event of failure . 67
9.4.1 General requirements . 67
9.4.2 Measures to minimize risk in the event of failure . 68
9.4.3 Protection against maloperation due to earth faults, voltage
interruptions and loss of circuit continuity malfunction of control circuits . 70
10 Operator interface and machine-mounted control devices . 77
10.1 General . 77
10.1.1 General device requirements . 77
10.1.2 Location and mounting . 77
10.1.3 Protection . 77
10.1.4 Position sensors . 77
10.1.5 Portable and pendant control stations . 78
10.2 Push-buttons Actuators . 78
10.2.1 Colours . 78
10.2.2 Markings . 79
10.3 Indicator lights and displays . 80
10.3.1 General . 80
10.3.2 Colours . 81
10.3.3 Flashing lights and displays . 81
10.4 Illuminated push-buttons . 81
10.5 Rotary control devices . 82
10.6 Start devices . 82
10.7 Emergency stop devices . 82
10.7.1 Location of emergency stop devices . 82
10.7.2 Types of emergency stop device . 82

10.7.3 Colour of actuators .
10.7.3 Local Operation of the supply disconnecting device to effect emergency
stop . 82
10.8 Emergency switching off devices . 83
10.8.1 Location of emergency switching off devices . 83
10.8.2 Types of emergency switching off device . 83
10.8.3 Colour of actuators .
10.8.3 Local operation of the supply disconnecting device to effect emergency
switching off . 83
10.9 Enabling control device . 83
11 Controlgear: location, mounting, and enclosures . 84
11.1 General requirements . 84
11.2 Location and mounting . 84
11.2.1 Accessibility and maintenance . 84
11.2.2 Physical separation or grouping . 84
11.2.3 Heating effects . 85
11.3 Degrees of protection. 85
11.4 Enclosures, doors and openings . 86
11.5 Access to controlgear electrical equipment . 87
12 Conductors and cables . 87
12.1 General requirements . 87
12.2 Conductors . 87
12.3 Insulation . 88
12.4 Current-carrying capacity in normal service . 89
12.5 Conductor and cable voltage drop . 90
12.6 Flexible cables . 91
12.6.1 General . 91
12.6.2 Mechanical rating . 91
12.6.3 Current-carrying capacity of cables wound on drums . 91
12.7 Conductor wires, conductor bars and slip-ring assemblies . 92
12.7.1 Basic protection against direct contact . 92
12.7.2 Protective conductors circuit . 92
12.7.3 Protective conductor current collectors . 93
12.7.4 Removable current collectors with a disconnector function . 93
12.7.5 Clearances in air . 93
12.7.6 Creepage distances . 93
12.7.7 Conductor system sectioning . 93
12.7.8 Construction and installation of conductor wire, conductor bar systems
and slip-ring assemblies . 93
13 Wiring practices . 94
13.1 Connections and routing . 94
13.1.1 General requirements . 94
13.1.2 Conductor and cable runs . 95
13.1.3 Conductors of different circuits . 95
13.1.4 AC circuits – Electromagnetic effects (prevention of eddy currents) . 95
13.1.5 Connection between pick-up and pick-up converter of an inductive
power supply system . 95
13.2 Identification of conductors . 96
13.2.1 General requirements . 96

– 6 – IEC 60204-1:2016 RLV © IEC 2016
13.2.2 Identification of the protective conductor / protective bonding conductor . 96
13.2.3 Identification of the neutral conductor . 97
13.2.4 Identification by colour . 97
13.3 Wiring inside enclosures . 98
13.4 Wiring outside enclosures . 98
13.4.1 General requirements . 98
13.4.2 External ducts . 98
13.4.3 Connection to moving elements of the machine . 98
13.4.4 Interconnection of devices on the machine . 100
13.4.5 Plug/socket combinations . 100
13.4.6 Dismantling for shipment . 101
13.4.7 Additional conductors . 101
13.5 Ducts, connection boxes and other boxes . 101
13.5.1 General requirements . 101
13.5.2 Percentage of fill of ducts .
13.5.2 Rigid metal conduit and fittings . 102
13.5.3 Flexible metal conduit and fittings . 102
13.5.4 Flexible non-metallic conduit and fittings . 102
13.5.5 Cable trunking systems . 102
13.5.6 Machine compartments and cable trunking systems. 103
13.5.7 Connection boxes and other boxes . 103
13.5.8 Motor connection boxes . 103
14 Electric motors and associated equipment . 103
14.1 General requirements . 103
14.2 Motor enclosures . 103
14.3 Motor dimensions. 103
14.4 Motor mounting and compartments . 104
14.5 Criteria for motor selection . 104
14.6 Protective devices for mechanical brakes . 104
15 Accessories Socket-outlets and lighting . 105
15.1 Socket-outlets for accessories . 105
15.2 Local lighting of the machine and of the equipment . 105
15.2.1 General . 105
15.2.2 Supply . 105
15.2.3 Protection . 106
15.2.4 Fittings . 106
16 Marking, warning signs and reference designations . 106
16.1 General . 106
16.2 Warning signs . 106
16.2.1 Electric shock hazard . 106
16.2.2 Hot surfaces hazard . 107
16.3 Functional identification . 107
16.4 Marking of enclosures of electrical equipment . 108
16.5 Reference designations . 108
17 Technical documentation . 108
17.1 General . 108
17.2 Information to be provided related to the electrical equipment . 109
17.3 Requirements applicable to all documentation .

17.4 Installation documents .
17.5 Overview diagrams and function diagrams .
17.6 Circuit diagrams .
17.7 Operating manual .
17.8 Maintenance manual .
17.9 Parts list .
18 Verification . 112
18.1 General . 112
18.2 Verification of conditions for protection by automatic disconnection of supply . 113
18.2.1 General . 113
18.2.2 Test methods in TN-systems .
18.2.2 Test 1 – Verification of the continuity of the protective bonding circuit . 114
18.2.3 Test 2 – Fault loop impedance verification and suitability of the
associated overcurrent protective device . 114
18.2.4 Application of the test methods for TN-systems . 114
18.3 Insulation resistance tests. 117
18.4 Voltage tests . 118
18.5 Protection against residual voltages . 118
18.6 Functional tests . 118
18.7 Retesting . 118
Annex A (normative) Protection against indirect contact in TN-systems Fault protection
by automatic disconnection of supply. 119
A.1 Fault protection for machines supplied from TN-systems . 119
A.1.1 General . 119
A.1.2 Conditions for protection by automatic disconnection of the supply by
overcurrent protective devices . 120
A.1.3 Condition for protection by reducing the touch voltage below 50 V . 121
A.1.4 Verification of conditions for protection by automatic disconnection of
the supply . 121
A.2 Fault protection for machines supplied from TT-systems . 124
A.2.1 Connection to earth . 124
A.2.2 Fault protection for TT systems . 124
A.2.3 Verification of protection by automatic disconnection of supply using a
residual current protective device . 126
A.2.4 Measurement of the fault loop impedance (Z ) . 126
s
Annex B (informative) Enquiry form for the electrical equipment of machines . 128
Annex C (informative) Examples of machines covered by this part of IEC 60204 . 132
Annex D (informative) Current-carrying capacity and overcurrent protection of
conductors and cables in the electrical equipment of machines . 134
D.1 General . 134
D.2 General operating conditions . 134
D.2.1 Ambient air temperature . 134
D.2.2 Methods of installation . 134
D.2.3 Grouping . 136
D.2.4 Classification of conductors . 137
D.3 Co-ordination between conductors and protective devices providing overload
protection. 137
D.4 Overcurrent protection of conductors . 138
D.5 Effect of harmonic currents on balanced three-phase systems . 139
Annex E (informative) Explanation of emergency operation functions . 140

– 8 – IEC 60204-1:2016 RLV © IEC 2016
Annex F (informative) Guide for the use of this part of IEC 60204 . 141
F.1 General .
Annex G (informative) Comparison of typical conductor cross-sectional areas . 143
Annex H (informative) Measures to reduce the effects of electromagnetic influences . 145
H.1 Definitions . 145
H.1.1 apparatus . 145
H.1.2 fixed installation . 145
H.2 General . 145
H.3 Mitigation of electromagnetic interference (EMI) . 145
H.3.1 General . 145
H.3.2 Measures to reduce EMI . 146
H.4 Separation and segregation of cables . 146
H.5 Power supply of a machine by parallel sources . 150
H.6 Supply impedance where a Power Drive System (PDS) is used . 150
Annex I (informative) Documentation / Information . 151
Bibliography . 153
Index .

Figure 1 – Block diagram of a typical machine . 14
Figure 2 – Disconnector isolator . 36
Figure 3 – Method a) .
Figure 3 – Disconnecting circuit breaker . 37
Figure 4 – Method b) .
Figure 4 – Example of equipotential bonding for electrical equipment of a machine . 52
Figure 5 – Symbol IEC 60417-5019: Protective earth . 56
Figure 6 – Symbol IEC 60417-5020: Frame or chassis . 57
Figure 7 – Method a) Earthed control circuit fed by a transformer . 71
Figure 8 – Method b1) Non-earthed control circuit fed by transformer . 72
Figure 9 – Method b2) Non-earthed control circuit fed by transformer . 72
Figure 10 – Method b3) Non-earthed control circuit fed by transformer . 73
Figure 11 – Method c) Control circuits fed by transformer with an earthed centre-tap
winding . 74
Figure 12 – Method d1a) Control circuit without transformer connected between a
phase and the neutral of an earthed supply system. 75
Figure 13 – Method d1b) Control circuit without transformer connected between two
phases of an earthed supply system . 75
Figure 14 – Method d2a) Control circuit without transformer connected between phase
and neutral of a non-earthed supply system . 76
Figure 15 – Method d2b) control circuit without transformer connected between two
phases of a non-earthed supply system . 76
Figure 16 – Symbol IEC 60417-5019. 96
Figure 17 – Symbol IEC 60417-5021. 97
Figure 18 – Symbol ISO 7010-W012 . 107
Figure 19 – Symbol ISO 7010-W017 . 107
Figure A.1 – Typical arrangement for fault loop impedance measurement .

Figure A.1 – Typical arrangement for fault loop impedance (Z ) measurement in TN
s
systems . 122
Figure A.2 – Typical arrangement for fault loop impedance (Z ) measurement for
s
power drive system circuits in TN systems . 123
Figure A.3 – Typical arrangement for fault loop impedance (Z ) measurement in TT
s
systems . 127
Figure A.4 – Typical arrangement for fault loop impedance (Z ) measurement for
s
power drive system circuits in TT systems . 127
Figure D.1 – Methods of conductor and cable installation independent of number of
conductors/cables . 135
Figure D.2 – Parameters of conductors and protective devices . 137
Figure H.1 – By-pass conductor for screen reinforcement . 146
Figure H.2 – Examples of vertical separation and segregation . 148
Figure H.3 – Examples of horizontal separation and segregation . 148
Figure H.4 – Cable arrangements in metal cable trays . 149
Figure H.5 – Connections between metal cable trays or cable trunking systems . 149
Figure H.6 – Interruption of metal cable trays at fire barriers . 150

Table 1 – Minimum cross-sectional area of the external copper protective conductors . 34
Table 2 – Colour-coding for push-button actuators and their meanings .
Table 2 – Symbols for push-buttons actuators (Power) . 80
Table 3 – Symbols for actuators (Machine operation) .
...

IEC 60204-1 ®
Edition 6.1 2021-09
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Safety of machinery –
Part 1: General requirements
Sécurité des machines –
Partie 1: Exigences générales
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IEC 60204-1 ®
Edition 6.1 2021-09
CONSOLIDATED VERSION
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Safety of machinery –
Part 1: General requirements
Sécurité des machines –
Partie 1: Exigences générales
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 13.110; 29.020 ISBN 978-2-8322-4040-3

IEC 60204-1 ®
Edition 6.1 2021-09
CONSOLIDATED VERSION
REDLINE VERSION
VERSION REDLINE
colour
inside
Safety of machinery –
Part 1: General requirements
Sécurité des machines –
Partie 1: Exigences générales
– 2 – IEC 60204-1:2016+AMD1:2021 CSV
© IEC 2021
CONTENTS
FOREWORD . 10
INTRODUCTION . 13
1 Scope . 15
2 Normative references. 16
3 Terms, definitions and abbreviated terms . 17
3.1 Terms and definitions . 17
3.2 Abbreviated terms . 26
4 General requirements . 26
4.1 General . 26
4.2 Selection of equipment . 27
4.2.1 General . 27
4.2.2 Switchgear . 28
4.3 Electrical supply . 28
4.3.1 General . 28
4.3.2 AC supplies . 28
4.3.3 DC supplies . 28
4.3.4 Special supply systems . 28
4.4 Physical environment and operating conditions . 29
4.4.1 General . 29
4.4.2 Electromagnetic compatibility (EMC) . 29
4.4.3 Ambient air temperature . 29
4.4.4 Humidity . 29
4.4.5 Altitude . 29
4.4.6 Contaminants . 30
4.4.7 Ionizing and non-ionizing radiation . 30
4.4.8 Vibration, shock, and bump . 30
4.5 Transportation and storage . 30
4.6 Provisions for handling . 30
5 Incoming supply conductor terminations and devices for disconnecting and
switching off . 30
5.1 Incoming supply conductor terminations . 30
5.2 Terminal for connection of the external protective conductor . 31
5.3 Supply disconnecting (isolating) device. 31
5.3.1 General . 31
5.3.2 Type . 32
5.3.3 Requirements . 32
5.3.4 Operating means of the supply disconnecting device . 33
5.3.5 Excepted circuits . 33
5.4 Devices for removal of power for prevention of unexpected start-up . 34
5.5 Devices for isolating electrical equipment . 35
5.6 Protection against unauthorized, inadvertent and/or mistaken connection . 35
6 Protection against electric shock . 35
6.1 General . 35
6.2 Basic protection . 36
6.2.1 General . 36
6.2.2 Protection by enclosures . 36

© IEC 2021
6.2.3 Protection by insulation of live parts . 37
6.2.4 Protection against residual voltages . 37
6.2.5 Protection by barriers . 37
6.2.6 Protection by placing out of reach or protection by obstacles . 37
6.3 Fault protection . 38
6.3.1 General . 38
6.3.2 Prevention of the occurrence of a touch voltage . 38
6.3.3 Protection by automatic disconnection of supply . 38
6.4 Protection by the use of PELV . 39
6.4.1 General requirements . 39
6.4.2 Sources for PELV . 40
7 Protection of equipment . 40
7.1 General . 40
7.2 Overcurrent protection . 41
7.2.1 General . 41
7.2.2 Supply conductors . 41
7.2.3 Power circuits . 41
7.2.4 Control circuits . 41
7.2.5 Socket outlets and their associated conductors . 42
7.2.6 Lighting circuits . 42
7.2.7 Transformers . 42
7.2.8 Location of overcurrent protective devices . 42
7.2.9 Overcurrent protective devices . 42
7.2.10 Rating and setting of overcurrent protective devices . 42
7.3 Protection of motors against overheating . 43
7.3.1 General . 43
7.3.2 Overload protection . 43
7.3.3 Over-temperature protection . 43
7.4 Protection against abnormal temperature . 44
7.5 Protection against the effects of supply interruption or voltage reduction and
subsequent restoration . 44
7.6 Motor overspeed protection . 44
7.7 Additional earth fault/residual current protection . 44
7.8 Phase sequence protection . 45
7.9 Protection against overvoltages due to lightning and to switching surges . 45
7.10 Short-circuit current rating . 45
8 Equipotential bonding . 46
8.1 General . 46
8.2 Protective bonding circuit . 48
8.2.1 General . 48
8.2.2 Protective conductors . 48
8.2.3 Continuity of the protective bonding circuit . 49
8.2.4 Protective conductor connecting points . 50
8.2.5 Mobile machines . 50
8.2.6 Additional requirements for electrical equipment having earth leakage
currents higher than 10 mA . 50
8.3 Measures to restrict the effects of high leakage current . 51
8.4 Functional bonding . 51
9 Control circuits and control functions . 51

– 4 – IEC 60204-1:2016+AMD1:2021 CSV
© IEC 2021
9.1 Control circuits . 51
9.1.1 Control circuit supply . 51
9.1.2 Control circuit voltages . 52
9.1.3 Protection . 52
9.2 Control functions . 52
9.2.1 General . 52
9.2.2 Categories of stop functions . 52
9.2.3 Operation . 52
9.2.4 Cableless control system (CCS) . 56
9.3 Protective interlocks . 58
9.3.1 Reclosing or resetting of an interlocking safeguard . 58
9.3.2 Exceeding operating limits. 58
9.3.3 Operation of auxiliary functions . 58
9.3.4 Interlocks between different operations and for contrary motions . 58
9.3.5 Reverse current braking . 59
9.3.6 Suspension of safety functions and/or protective measures . 59
9.4 Control functions in the event of failure . 59
9.4.1 General requirements . 59
9.4.2 Measures to minimize risk in the event of failure . 60
9.4.3 Protection against malfunction of control circuits . 61
10 Operator interface and machine-mounted control devices . 68
10.1 General . 68
10.1.1 General requirements . 68
10.1.2 Location and mounting . 68
10.1.3 Protection . 68
10.1.4 Position sensors . 68
10.1.5 Portable and pendant control stations . 69
10.2 Actuators . 69
10.2.1 Colours . 69
10.2.2 Markings . 69
10.3 Indicator lights and displays . 70
10.3.1 General . 70
10.3.2 Colours . 70
10.3.3 Flashing lights and displays . 71
10.4 Illuminated push-buttons . 71
10.5 Rotary control devices . 71
10.6 Start devices . 71
10.7 Emergency stop devices . 72
10.7.1 Location of emergency stop devices . 72
10.7.2 Types of emergency stop device . 72
10.7.3 Operation of the supply disconnecting device to effect emergency stop . 72
10.8 Emergency switching off devices . 72
10.8.1 Location of emergency switching off devices . 72
10.8.2 Types of emergency switching off device . 72
10.8.3 Local operation of the supply disconnecting device to effect emergency
switching off . 73
10.9 Enabling control device . 73
11 Controlgear: location, mounting, and enclosures . 73
11.1 General requirements . 73

© IEC 2021
11.2 Location and mounting . 73
11.2.1 Accessibility and maintenance . 73
11.2.2 Physical separation or grouping . 74
11.2.3 Heating effects . 74
11.3 Degrees of protection . 75
11.4 Enclosures, doors and openings . 75
11.5 Access to electrical equipment . 76
12 Conductors and cables . 76
12.1 General requirements . 76
12.2 Conductors . 76
12.3 Insulation . 77
12.4 Current-carrying capacity in normal service . 77
12.5 Conductor and cable voltage drop . 78
12.6 Flexible cables . 79
12.6.1 General . 79
12.6.2 Mechanical rating . 79
12.6.3 Current-carrying capacity of cables wound on drums . 79
12.7 Conductor wires, conductor bars and slip-ring assemblies . 80
12.7.1 Basic protection . 80
12.7.2 Protective conductors . 80
12.7.3 Protective conductor current collectors . 80
12.7.4 Removable current collectors with a disconnector function . 81
12.7.5 Clearances in air . 81
12.7.6 Creepage distances . 81
12.7.7 Conductor system sectioning . 81
12.7.8 Construction and installation of conductor wire, conductor bar systems
and slip-ring assemblies . 81
13 Wiring practices . 82
13.1 Connections and routing . 82
13.1.1 General requirements . 82
13.1.2 Conductor and cable runs . 82
13.1.3 Conductors of different circuits . 83
13.1.4 AC circuits – Electromagnetic effects (prevention of eddy currents) . 83
13.1.5 Connection between pick-up and pick-up converter of an inductive
power supply system . 83
13.2 Identification of conductors . 83
13.2.1 General requirements . 83
13.2.2 Identification of the protective conductor / protective bonding conductor . 84
13.2.3 Identification of the neutral conductor . 84
13.2.4 Identification by colour . 85
13.3 Wiring inside enclosures . 85
13.4 Wiring outside enclosures . 86
13.4.1 General requirements . 86
13.4.2 External ducts . 86
13.4.3 Connection to moving elements of the machine . 86
13.4.4 Interconnection of devices on the machine . 87
13.4.5 Plug/socket combinations . 87
13.4.6 Dismantling for shipment . 88
13.4.7 Additional conductors . 88

– 6 – IEC 60204-1:2016+AMD1:2021 CSV
© IEC 2021
13.5 Ducts, connection boxes and other boxes . 88
13.5.1 General requirements . 88
13.5.2 Rigid metal conduit and fittings . 89
13.5.3 Flexible metal conduit and fittings . 89
13.5.4 Flexible non-metallic conduit and fittings . 89
13.5.5 Cable trunking systems . 90
13.5.6 Machine compartments and cable trunking systems . 90
13.5.7 Connection boxes and other boxes . 90
13.5.8 Motor connection boxes . 90
14 Electric motors and associated equipment . 90
14.1 General requirements . 90
14.2 Motor enclosures . 90
14.3 Motor dimensions . 91
14.4 Motor mounting and compartments . 91
14.5 Criteria for motor selection . 91
14.6 Protective devices for mechanical brakes . 91
15 Socket-outlets and lighting . 92
15.1 Socket-outlets for accessories . 92
15.2 Local lighting of the machine and of the equipment . 92
15.2.1 General . 92
15.2.2 Supply . 92
15.2.3 Protection . 93
15.2.4 Fittings . 93
16 Marking, warning signs and reference designations . 93
16.1 General . 93
16.2 Warning signs . 93
16.2.1 Electric shock hazard . 93
16.2.2 Hot surfaces hazard . 94
16.3 Functional identification . 94
16.4 Marking of enclosures of electrical equipment . 94
16.5 Reference designations . 95
17 Technical documentation . 95
17.1 General . 95
17.2 Information related to the electrical equipment . 95
18 Verification . 96
18.1 General . 96
18.2 Verification of conditions for protection by automatic disconnection of supply . 97
18.2.1 General . 97
18.2.2 Test 1 – Verification of the continuity of the protective bonding circuit . 97
18.2.3 Test 2 – Fault loop impedance verification and suitability of the
associated overcurrent protective device . 97
18.2.4 Application of the test methods for TN-systems. 98
18.3 Insulation resistance tests . 100
18.4 Voltage tests . 101
18.5 Protection against residual voltages . 101
18.6 Functional tests . 101
18.7 Retesting . 101
Annex A (normative) Fault protection by automatic disconnection of supply . 102

© IEC 2021
A.1 Fault protection for machines supplied from TN-systems . 102
A.1.1 General . 102
A.1.2 Conditions for protection by automatic disconnection of the supply by
overcurrent protective devices . 102
A.1.3 Condition for protection by reducing the touch voltage below 50 V . 103
A.1.4 Verification of conditions for protection by automatic disconnection of
the supply . 104
A.2 Fault protection for machines supplied from TT-systems . 106
A.2.1 Connection to earth . 106
A.2.2 Fault protection for TT systems . 106
A.2.3 Verification of protection by automatic disconnection of supply using a

residual current protective device . 107
A.2.4 Measurement of the fault loop impedance (Z ) . 108
s
Annex B (informative) Enquiry form for the electrical equipment of machines . 110
Annex C (informative) Examples of machines covered by this part of IEC 60204 . 114
Annex D (informative) Current-carrying capacity and overcurrent protection of
conductors and cables in the electrical equipment of machines . 116
D.1 General . 116
D.2 General operating conditions . 116
D.2.1 Ambient air temperature . 116
D.2.2 Methods of installation . 116
D.2.3 Grouping . 118
D.2.4 Classification of conductors . 119
D.3 Co-ordination between conductors and protective devices providing overload
protection . 119
D.4 Overcurrent protection of conductors . 120
D.5 Effect of harmonic currents on balanced three-phase systems . 121
Annex E (informative) Explanation of emergency operation functions . 122
Annex F (informative) Guide for the use of this part of IEC 60204 . 123
Annex G (informative) Comparison of typical conductor cross-sectional areas . 125
Annex H (informative) Measures to reduce the effects of electromagnetic influences . 127
H.1 Definitions . 127
H.1.1 apparatus . 127
H.1.2 fixed installation . 127
H.2 General . 127
H.3 Mitigation of electromagnetic interference (EMI) . 128
H.3.1 General . 128
H.3.2 Measures to reduce EMI . 128
H.4 Separation and segregation of cables . 129
H.5 Power supply of a machine by parallel sources . 132
H.6 Supply impedance where a Power Drive System (PDS) is used . 132
Annex I (informative) Documentation / Information . 133
Bibliography . 135

Figure 1 – Block diagram of a typical machine . 14
Figure 2 – Disconnector isolator . 33
Figure 3 – Disconnecting circuit breaker . 33
Figure 4 – Example of equipotential bonding for electrical equipment of a machine . 47

– 8 – IEC 60204-1:2016+AMD1:2021 CSV
© IEC 2021
Figure 5 – Symbol IEC 60417-5019: Protective earth . 50
Figure 6 – Symbol IEC 60417-5020: Frame or chassis . 51
Figure 7 – Method a) Earthed control circuit fed by a transformer . 62
Figure 8 – Method b1) Non-earthed control circuit fed by transformer . 63
Figure 9 – Method b2) Non-earthed control circuit fed by transformer . 63
Figure 10 – Method b3) Non-earthed control circuit fed by transformer . 64
Figure 11 – Method c) Control circuits fed by transformer with an earthed centre-tap
winding . 65
Figure 12 – Method d1a) Control circuit without transformer connected between a

phase and the neutral of an earthed supply system . 66
Figure 13 – Method d1b) Control circuit without transformer connected between two
phases of an earthed supply system . 66
Figure 14 – Method d2a) Control circuit without transformer connected between phase
and neutral of a non-earthed supply system . 67
Figure 15 – Method d2b) control circuit without transformer connected between two

phases of a non-earthed supply system . 67
Figure 16 – Symbol IEC 60417-5019 . 84
Figure 17 – Symbol IEC 60417-5021 . 84
Figure 18 – Symbol ISO 7010-W012. 94
Figure 19 – Symbol ISO 7010-W017. 94
Figure A.1 – Typical arrangement for fault loop impedance (Z ) measurement in TN
s
systems . 105
Figure A.2 – Typical arrangement for fault loop impedance (Z ) measurement for
s
power drive system circuits in TN systems . 105
Figure A.3 – Typical arrangement for fault loop impedance (Z ) measurement in TT
s
systems . 108
Figure A.4 – Typical arrangement for fault loop impedance (Z ) measurement for
s
power drive system circuits in TT systems . 109
Figure D.1 – Methods of conductor and cable installation independent of number of
conductors/cables . 117
Figure D.2 – Parameters of conductors and protective devices . 119
Figure H.1 – By-pass conductor for screen reinforcement . 128
Figure H.2 – Examples of vertical separation and segregation . 130
Figure H.3 – Examples of horizontal separation and segregation . 130
Figure H.4 – Cable arrangements in metal cable trays . 131
Figure H.5 – Connections between metal cable trays or cable trunking systems . 131
Figure H.6 – Interruption of metal cable trays at fire barriers . 132

Table 1 – Minimum cross-sectional area of copper protective conductors . 31
Table 2 – Symbols for actuators (Power) . 70
Table 3 – Symbols for actuators (Machine operation) . 70
Table 4 – Colours for indicator lights and their meanings with respect to the condition
of the machine . 71
Table 5 – Minimum cross-sectional areas of copper conductors . 77
Table 6 – Examples of current-carrying capacity (I ) of PVC insulated copper
z
conductors or cables under steady-state conditions in an ambient air temperature of
+40 °C for different methods of installation . 78

© IEC 2021
Table 7 – Derating factors for cables wound on drums . 80
Table 8 – Minimum permitted bending radii for the forced guiding of flexible cables . 87
...

IEC 60204-1 ®
Edition 6.0 2016-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Safety of machinery – Electrical equipment of machines –
Part 1: General requirements
Sécurité des machines – Équipement électrique des machines –
Partie 1: Exigences générales
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IEC 60204-1 ®
Edition 6.0 2016-10
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Safety of machinery – Electrical equipment of machines –

Part 1: General requirements
Sécurité des machines – Équipement électrique des machines –

Partie 1: Exigences générales
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 13.110; 29.020 ISBN 978-2-8322-3621-5

– 2 – IEC 60204-1:2016 © IEC 2016
CONTENTS
FOREWORD . 10
INTRODUCTION . 13
1 Scope . 15
2 Normative references. 16
3 Terms,definitions and abbreviated terms . 17
3.1 Terms and definitions . 17
3.2 Abbreviated terms . 26
4 General requirements . 26
4.1 General . 26
4.2 Selection of equipment . 27
4.2.1 General . 27
4.2.2 Switchgear . 27
4.3 Electrical supply . 28
4.3.1 General . 28
4.3.2 AC supplies . 28
4.3.3 DC supplies . 28
4.3.4 Special supply systems . 28
4.4 Physical environment and operating conditions . 28
4.4.1 General . 28
4.4.2 Electromagnetic compatibility (EMC) . 29
4.4.3 Ambient air temperature . 29
4.4.4 Humidity . 29
4.4.5 Altitude . 29
4.4.6 Contaminants . 29
4.4.7 Ionizing and non-ionizing radiation . 30
4.4.8 Vibration, shock, and bump . 30
4.5 Transportation and storage . 30
4.6 Provisions for handling . 30
5 Incoming supply conductor terminations and devices for disconnecting and
switching off . 30
5.1 Incoming supply conductor terminations . 30
5.2 Terminal for connection of the external protective conductor . 31
5.3 Supply disconnecting (isolating) device. 31
5.3.1 General . 31
5.3.2 Type . 31
5.3.3 Requirements . 32
5.3.4 Operating means of the supply disconnecting device . 32
5.3.5 Excepted circuits . 33
5.4 Devices for removal of power for prevention of unexpected start-up . 34
5.5 Devices for isolating electrical equipment . 34
5.6 Protection against unauthorized, inadvertent and/or mistaken connection . 35
6 Protection against electric shock . 35
6.1 General . 35
6.2 Basic protection . 35
6.2.1 General . 35
6.2.2 Protection by enclosures . 36

6.2.3 Protection by insulation of live parts . 37
6.2.4 Protection against residual voltages . 37
6.2.5 Protection by barriers . 37
6.2.6 Protection by placing out of reach or protection by obstacles . 37
6.3 Fault protection . 37
6.3.1 General . 37
6.3.2 Prevention of the occurrence of a touch voltage . 38
6.3.3 Protection by automatic disconnection of supply . 38
6.4 Protection by the use of PELV . 39
6.4.1 General requirements . 39
6.4.2 Sources for PELV . 40
7 Protection of equipment . 40
7.1 General . 40
7.2 Overcurrent protection . 40
7.2.1 General . 40
7.2.2 Supply conductors . 40
7.2.3 Power circuits . 41
7.2.4 Control circuits . 41
7.2.5 Socket outlets and their associated conductors . 41
7.2.6 Lighting circuits . 41
7.2.7 Transformers . 42
7.2.8 Location of overcurrent protective devices . 42
7.2.9 Overcurrent protective devices . 42
7.2.10 Rating and setting of overcurrent protective devices . 42
7.3 Protection of motors against overheating . 42
7.3.1 General . 42
7.3.2 Overload protection . 43
7.3.3 Over-temperature protection . 43
7.4 Protection against abnormal temperature . 43
7.5 Protection against the effects of supply interruption or voltage reduction and
subsequent restoration . 44
7.6 Motor overspeed protection . 44
7.7 Additional earth fault/residual current protection . 44
7.8 Phase sequence protection . 44
7.9 Protection against overvoltages due to lightning and to switching surges . 44
7.10 Short-circuit current rating . 45
8 Equipotential bonding . 45
8.1 General . 45
8.2 Protective bonding circuit . 47
8.2.1 General . 47
8.2.2 Protective conductors . 47
8.2.3 Continuity of the protective bonding circuit . 48
8.2.4 Protective conductor connecting points . 49
8.2.5 Mobile machines . 49
8.2.6 Additional requirements for electrical equipment having earth leakage
currents higher than 10 mA . 49
8.3 Measures to restrict the effects of high leakage current . 50
8.4 Functional bonding . 50
9 Control circuits and control functions . 50

– 4 – IEC 60204-1:2016 © IEC 2016
9.1 Control circuits . 50
9.1.1 Control circuit supply . 50
9.1.2 Control circuit voltages . 51
9.1.3 Protection . 51
9.2 Control functions . 51
9.2.1 General . 51
9.2.2 Categories of stop functions . 51
9.2.3 Operation . 51
9.2.4 Cableless control system (CCS) . 55
9.3 Protective interlocks . 57
9.3.1 Reclosing or resetting of an interlocking safeguard . 57
9.3.2 Exceeding operating limits. 57
9.3.3 Operation of auxiliary functions . 57
9.3.4 Interlocks between different operations and for contrary motions . 57
9.3.5 Reverse current braking . 57
9.3.6 Suspension of safety functions and/or protective measures . 58
9.4 Control functions in the event of failure . 58
9.4.1 General requirements . 58
9.4.2 Measures to minimize risk in the event of failure . 59
9.4.3 Protection against malfunction of control circuits . 60
10 Operator interface and machine-mounted control devices . 66
10.1 General . 66
10.1.1 General requirements . 66
10.1.2 Location and mounting . 66
10.1.3 Protection . 66
10.1.4 Position sensors . 66
10.1.5 Portable and pendant control stations . 67
10.2 Actuators . 67
10.2.1 Colours . 67
10.2.2 Markings . 67
10.3 Indicator lights and displays . 68
10.3.1 General . 68
10.3.2 Colours . 68
10.3.3 Flashing lights and displays . 69
10.4 Illuminated push-buttons . 69
10.5 Rotary control devices . 69
10.6 Start devices . 69
10.7 Emergency stop devices . 70
10.7.1 Location of emergency stop devices . 70
10.7.2 Types of emergency stop device . 70
10.7.3 Operation of the supply disconnecting device to effect emergency stop . 70
10.8 Emergency switching off devices . 70
10.8.1 Location of emergency switching off devices . 70
10.8.2 Types of emergency switching off device . 70
10.8.3 Local operation of the supply disconnecting device to effect emergency
switching off . 71
10.9 Enabling control device . 71
11 Controlgear: location, mounting, and enclosures . 71
11.1 General requirements . 71

11.2 Location and mounting . 71
11.2.1 Accessibility and maintenance . 71
11.2.2 Physical separation or grouping . 72
11.2.3 Heating effects . 72
11.3 Degrees of protection . 73
11.4 Enclosures, doors and openings . 73
11.5 Access to electrical equipment . 74
12 Conductors and cables . 74
12.1 General requirements . 74
12.2 Conductors . 74
12.3 Insulation . 75
12.4 Current-carrying capacity in normal service . 75
12.5 Conductor and cable voltage drop . 76
12.6 Flexible cables . 77
12.6.1 General . 77
12.6.2 Mechanical rating . 77
12.6.3 Current-carrying capacity of cables wound on drums . 77
12.7 Conductor wires, conductor bars and slip-ring assemblies . 78
12.7.1 Basic protection . 78
12.7.2 Protective conductors . 78
12.7.3 Protective conductor current collectors . 78
12.7.4 Removable current collectors with a disconnector function . 79
12.7.5 Clearances in air . 79
12.7.6 Creepage distances . 79
12.7.7 Conductor system sectioning . 79
12.7.8 Construction and installation of conductor wire, conductor bar systems
and slip-ring assemblies . 79
13 Wiring practices . 80
13.1 Connections and routing . 80
13.1.1 General requirements . 80
13.1.2 Conductor and cable runs . 80
13.1.3 Conductors of different circuits . 81
13.1.4 AC circuits – Electromagnetic effects (prevention of eddy currents) . 81
13.1.5 Connection between pick-up and pick-up converter of an inductive
power supply system . 81
13.2 Identification of conductors . 81
13.2.1 General requirements . 81
13.2.2 Identification of the protective conductor / protective bonding conductor . 82
13.2.3 Identification of the neutral conductor . 82
13.2.4 Identification by colour . 83
13.3 Wiring inside enclosures . 83
13.4 Wiring outside enclosures . 84
13.4.1 General requirements . 84
13.4.2 External ducts . 84
13.4.3 Connection to moving elements of the machine . 84
13.4.4 Interconnection of devices on the machine . 85
13.4.5 Plug/socket combinations . 85
13.4.6 Dismantling for shipment . 86
13.4.7 Additional conductors . 86

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13.5 Ducts, connection boxes and other boxes . 86
13.5.1 General requirements . 86
13.5.2 Rigid metal conduit and fittings . 87
13.5.3 Flexible metal conduit and fittings . 87
13.5.4 Flexible non-metallic conduit and fittings . 87
13.5.5 Cable trunking systems . 87
13.5.6 Machine compartments and cable trunking systems . 88
13.5.7 Connection boxes and other boxes . 88
13.5.8 Motor connection boxes . 88
14 Electric motors and associated equipment . 88
14.1 General requirements . 88
14.2 Motor enclosures . 88
14.3 Motor dimensions . 89
14.4 Motor mounting and compartments . 89
14.5 Criteria for motor selection . 89
14.6 Protective devices for mechanical brakes . 89
15 Socket-outlets and lighting . 90
15.1 Socket-outlets for accessories . 90
15.2 Local lighting of the machine and of the equipment . 90
15.2.1 General . 90
15.2.2 Supply . 90
15.2.3 Protection . 91
15.2.4 Fittings . 91
16 Marking, warning signs and reference designations . 91
16.1 General . 91
16.2 Warning signs . 91
16.2.1 Electric shock hazard . 91
16.2.2 Hot surfaces hazard . 92
16.3 Functional identification . 92
16.4 Marking of enclosures of electrical equipment . 92
16.5 Reference designations . 92
17 Technical documentation . 92
17.1 General . 92
17.2 Information related to the electrical equipment . 93
18 Verification . 94
18.1 General . 94
18.2 Verification of conditions for protection by automatic disconnection of supply . 94
18.2.1 General . 94
18.2.2 Test 1 – Verification of the continuity of the protective bonding circuit . 95
18.2.3 Test 2 – Fault loop impedance verification and suitability of the
associated overcurrent protective device . 95
18.2.4 Application of the test methods for TN-systems. 95
18.3 Insulation resistance tests . 97
18.4 Voltage tests . 98
18.5 Protection against residual voltages . 98
18.6 Functional tests . 98
18.7 Retesting . 98
Annex A (normative) Fault protection by automatic disconnection of supply . 99

A.1 Fault protection for machines supplied from TN-systems . 99
A.1.1 General . 99
A.1.2 Conditions for protection by automatic disconnection of the supply by
overcurrent protective devices . 99
A.1.3 Condition for protection by reducing the touch voltage below 50 V . 100
A.1.4 Verification of conditions for protection by automatic disconnection of
the supply . 101
A.2 Fault protection for machines supplied from TT-systems . 103
A.2.1 Connection to earth . 103
A.2.2 Fault protection for TT systems . 103
A.2.3 Verification of protection by automatic disconnection of supply using a
residual current protective device . 104
A.2.4 Measurement of the fault loop impedance (Z ) . 105
s
Annex B (informative) Enquiry form for the electrical equipment of machines . 107
Annex C (informative) Examples of machines covered by this part of IEC 60204 . 111
Annex D (informative) Current-carrying capacity and overcurrent protection of
conductors and cables in the electrical equipment of machines . 113
D.1 General . 113
D.2 General operating conditions . 113
D.2.1 Ambient air temperature . 113
D.2.2 Methods of installation . 113
D.2.3 Grouping . 115
D.2.4 Classification of conductors . 116
D.3 Co-ordination between conductors and protective devices providing overload
protection . 116
D.4 Overcurrent protection of conductors . 117
D.5 Effect of harmonic currents on balanced three-phase systems . 118
Annex E (informative) Explanation of emergency operation functions . 119
Annex F (informative) Guide for the use of this part of IEC 60204 . 120
Annex G (informative) Comparison of typical conductor cross-sectional areas . 122
Annex H (informative) Measures to reduce the effects of electromagnetic influences . 124
H.1 Definitions . 124
H.1.1 apparatus . 124
H.1.2 fixed installation . 124
H.2 General . 124
H.3 Mitigation of electromagnetic interference (EMI) . 124
H.3.1 General . 124
H.3.2 Measures to reduce EMI . 125
H.4 Separation and segregation of cables . 125
H.5 Power supply of a machine by parallel sources . 129
H.6 Supply impedance where a Power Drive System (PDS) is used . 129
Annex I (informative) Documentation / Information . 130
Bibliography . 132

Figure 1 – Block diagram of a typical machine . 14
Figure 2 – Disconnector isolator . 33
Figure 3 – Disconnecting circuit breaker . 33
Figure 4 – Example of equipotential bonding for electrical equipment of a machine . 46

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Figure 5 – Symbol IEC 60417-5019: Protective earth . 49
Figure 6 – Symbol IEC 60417-5020: Frame or chassis . 50
Figure 7 – Method a) Earthed control circuit fed by a transformer . 60
Figure 8 – Method b1) Non-earthed control circuit fed by transformer . 61
Figure 9 – Method b2) Non-earthed control circuit fed by transformer . 62
Figure 10 – Method b3) Non-earthed control circuit fed by transformer . 62
Figure 11 – Method c) Control circuits fed by transformer with an earthed centre-tap
winding . 63
Figure 12 – Method d1a) Control circuit without transformer connected between a
phase and the neutral of an earthed supply system . 64
Figure 13 – Method d1b) Control circuit without transformer connected between two
phases of an earthed supply system . 64
Figure 14 – Method d2a) Control circuit without transformer connected between phase
and neutral of a non-earthed supply system . 65
Figure 15 – Method d2b) control circuit without transformer connected between two
phases of a non-earthed supply system . 65
Figure 16 – Symbol IEC 60417-5019 . 82
Figure 17 – Symbol IEC 60417-5021 . 82
Figure 18 – Symbol ISO 7010-W012. 91
Figure 19 – Symbol ISO 7010-W017. 92
Figure A.1 – Typical arrangement for fault loop impedance (Z ) measurement in TN
s
systems . 102
Figure A.2 – Typical arrangement for fault loop impedance (Z ) measurement for
s
power drive system circuits in TN systems . 102
Figure A.3 – Typical arrangement for fault loop impedance (Z ) measurement in TT
s
systems . 105
Figure A.4 – Typical arrangement for fault loop impedance (Z ) measurement for
s
power drive system circuits in TT systems . 106
Figure D.1 – Methods of conductor and cable installation independent of number of
conductors/cables . 114
Figure D.2 – Parameters of conductors and protective devices . 116
Figure H.1 – By-pass conductor for screen reinforcement . 125
Figure H.2 – Examples of vertical separation and segregation . 127
Figure H.3 – Examples of horizontal separation and segregation . 127
Figure H.4 – Cable arrangements in metal cable trays . 128
Figure H.5 – Connections between metal cable trays or cable trunking systems . 128
Figure H.6 – Interruption of metal cable trays at fire barriers . 129

Table 1 – Minimum cross-sectional area of copper protective conductors . 31
Table 2 – Symbols for actuators (Power) . 68
Table 3 – Symbols for actuators (Machine operation) . 68
Table 4 – Colours for indicator lights and their meanings with respect to the condition
of the machine . 69
Table 5 – Minimum cross-sectional areas of copper conductors . 75

Table 6 – Examples of curre
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