IEC 60519-4:2021

IEC 60519-4 ®
Edition 5.0 2021-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Safety in installations for electroheating and electromagnetic processing –
Part 4: Particular requirements for arc furnace installations

Sécurité dans les installations destinées au traitement électrothermique et
électromagnétique –
Partie 4: Exigences particulières pour les installations de fours à arc

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IEC 60519-4 ®
Edition 5.0 2021-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Safety in installations for electroheating and electromagnetic processing –

Part 4: Particular requirements for arc furnace installations

Sécurité dans les installations destinées au traitement électrothermique et

électromagnétique –
Partie 4: Exigences particulières pour les installations de fours à arc

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 25.180.10 ISBN 978-2-8322-1059-1

– 2 – IEC 60519-4:2021 © IEC 2021
CONTENTS
FOREWORD . 6
INTRODUCTION . 9
1 Scope . 10
2 Normative references . 10
3 Terms, definitions and abbreviated terms . 11
3.1 General concepts . 11
3.2 Equipment and state of equipment . 11
3.3 Parts and accessories . 14
3.4 Safety related concepts . 14
3.5 Abbreviated terms . 14
4 Classification and subdivision of equipment and installations . 14
4.1 Classification by processing frequency. 14
4.2 Classification by voltage . 14
4.3 Subdivision of installation and equipment . 14
4.4 Classification of hazards and risks . 14
5 Risk assessment . 15
6 General provisions. 15
6.1 Basic considerations . 15
6.2 Significant hazards . 15
6.3 Physical environment and operating conditions for the installation as such
and electrical equipment outside the processing equipment . 15
6.4 Physical environment and operating conditions for electrical equipment
caused by operation of the processing equipment . 16
6.5 Power supply . 16
6.6 Access . 17
6.7 Ergonomic aspects . 17
6.8 Transport and storage . 17
6.9 Provisions for handling. 17
6.10 Consumables and replaceable parts . 18
7 Protection against hazards from electric shock . 18
7.1 General . 18
7.2 Fundamental rule of protection . 18
7.3 General provisions . 18
7.4 Basic protection . 19
7.5 Provisions for protection in electric single fault condition . 19
7.6 Protective equipotential bonding . 19
7.7 Additional provisions for fault protection for frequencies above 200 Hz . 20
7.8 Currents in protective conductors . 20
7.9 Touch current and touch voltage . 20
7.10 Conductors and insulations at high temperature . 20
7.11 Non-electric faults . 20
8 Protection against hazards from electric or magnetic fields . 20
8.1 General . 20
8.2 Magnetic fields . 21
8.3 Magnetic fields below 1 Hz . 21
8.4 Local electric fields . 21

8.5 Requirements related to barriers and screens . 21
8.6 Requirements related to objects worn, carried or held by persons . 21
9 Protection against hazards from radiation . 21
9.1 General . 21
9.2 Installation or equipment generating ionizing radiation . 21
9.3 Ultraviolet radiation . 21
9.4 Visible and infrared radiation . 21
9.5 Laser sources . 22
10 Protection against hazards from thermal influences . 22
10.1 General . 22
10.2 Surface temperature limits for protection against burn . 22
10.3 Hazards caused by working conditions . 22
10.4 Temperature resistance of components. 22
10.5 Cooling . 23
10.6 Over-temperature protection . 23
11 Protection against hazards from fire . 23
12 Protection against hazards from fluids . 23
13 Specific requirements for components and subassemblies . 23
13.1 General . 23
13.2 Electrical equipment and conductors . 23
13.3 Connection to the electrical supply network and internal connections . 24
13.4 Isolation and switching . 24
13.5 Sensors and actuators safeguarding moving parts . 26
13.6 Motors . 26
13.7 Non electric-heating means . 26
13.8 Lighting . 26
13.9 Structural parts and stability. 27
13.10 Doors, windows and other openings . 27
13.11 Transformers, inductors, capacitors . 27
13.12 Handheld applicators . 27
13.13 Vacuum systems . 27
13.14 Protective and reactive gas generator . 27
14 Control of the installation or equipment . 27
14.1 General . 27
14.2 Operator control unit . 27
14.3 Emergency stop . 28
14.4 Control systems and their safety functions . 28
14.5 Controlgear . 28
14.6 Protective devices . 28
14.7 Over-temperature protection devices and systems . 28
14.8 Overpressure safety device . 28
15 Protection against mechanical hazards . 29
16 Protection against hazards resulting from use . 29
16.1 Particular hazards in processing of food, feed, cosmetics and similar
intended for human or animal consumption . 29
16.2 Combination equipment . 29
17 EMC . 29
17.1 Radio frequency interference . 29

– 4 – IEC 60519-4:2021 © IEC 2021
17.2 Immunity . 29
18 Verification and testing . 29
18.1 General . 29
18.2 Performing measurements and tests . 31
18.3 Verification of requirements from references . 31
18.4 Examination of drawings or calculations . 32
18.5 Visual inspection . 32
18.6 Measurements . 32
18.6.1 Environment and operating conditions inside the processing equipment . 32
18.6.2 Impedance of protective bonding . 32
18.6.3 Insulation resistance measurement . 32
18.6.4 Measurement of electric or magnetic fields . 34
18.6.5 Touch current measurement . 34
18.6.6 Measurement of ionising radiation . 34
18.6.7 Measurement of non-coherent optical irradiation . 34
18.6.8 Measurement of coherent optical radiation. 34
18.6.9 Surface temperature measurement . 34
18.6.10 Temperature of structural components subject to heat . 34
18.7 Functional tests . 34
18.7.1 Protection by automatic disconnection of supply . 34
18.7.2 Voltage test . 34
18.7.3 Dielectric test . 34
18.7.4 Accessibility of live parts . 35
18.8 Numerical calculations and modelling . 35
19 Information for use . 35
19.1 General requirements . 35
19.2 Location and nature of the information for use . 35
19.3 Signalling and warning devices . 35
19.4 Markings, pictograms, written warnings . 35
19.5 Instruction handbook . 35
Annex A (normative) Lists of significant hazards . 37
Annex B (normative) Limits to touch currents . 38
Annex C (normative) Non coherent optical radiation – Limits and risk classes. 39
Annex D (normative) Electric and magnetic fields . 40
Annex E (normative) Surface temperature limits . 41
Annex F (normative) EH, EMP and fire. 42
Annex G (normative) Marking and warning . 43
Annex H (normative) Guidelines on using this document . 44
Annex I (informative) Connection with ISO 13577 (all parts). 45
Annex J (informative) Requirements specific to the EU and associated countries. 46
Annex AA (normative) Systems to assure improved safety for personnel working in the
vicinity of electrodes and other live parts of secondary circuit . 47
Annex BB (normative) Limits to touch currents . 53
Bibliography . 54

Figure AA.1 – AC furnace supply according to design arrangements "a" . 49
Figure AA.2 – AC furnace supply according to design arrangements "b" . 49
Figure AA.3 – AC furnace supply according to design arrangements "c" . 50
Figure AA.4 – DC furnace supply according to design arrangements "d" . 51
Figure AA.5 – DC furnace supply according to design arrangements "e" . 51
Figure AA.6 – Six electrode AC furnace supply with current converter according to
design arrangements "f" . 52

Table 1 – Methods for the verification of requirements . 30
Table 101 – Test voltages of the Insulation measurement . 33
Table 102 – Installation progress of EAF and LF . 33

– 6 – IEC 60519-4:2021 © IEC 2021
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SAFETY IN INSTALLATIONS FOR ELECTROHEATING
AND ELECTROMAGNETIC PROCESSING –

Part 4: Particular requirements for arc furnace installations

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
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6) All users should ensure that they have the latest edition of this publication.
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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.
IEC 60519-4 has been prepared by IEC technical committee 27: Industrial electroheating and
electromagnetic processing. It is an International Standard.
This fifth edition cancels and replaces the fourth edition published in 2013. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) the structure has been redrafted according to IEC 60519-1:2020;
b) the scope and object have been redrafted;
c) the terms and definitions, normative references and bibliography have been updated and
completed;
d) the requirements have been redrafted according to IEC 60519-1:2020;
e) all provisions have been redrafted and the text is more concise with respect to submerged
arc furnace installations;
f) the annexes have been restructured, with respect to details concerning high voltage designs
and non-electrical issues, however to be aware of in those installations;
g) the aspect of noise has been removed from the scope;
h) the EMC requirements have been clarified;
i) risk classification of hazards have been based on emission;
j) the boundaries to ISO 13577 (all parts) and ISO 13578 have been clarified.
The text of this International Standard is based on the following documents:
FDIS Report on voting
27/1141/FDIS 27/1143/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/standardsdev/publications.
A list of all parts in the IEC 60519 series, published under the general title Safety in installations
for electroheating and electromagnetic processing, can be found on the IEC website.
The clauses of this standard supplement or modify the corresponding clauses of IEC 60519-
1:2020 (General Requirements hereinafter called "Part 1").
This part of IEC 60519 is to be read in conjunction with Part 1. It supplements or modifies the
corresponding clauses of Part 1. Where the text indicates an "addition" to or a "replacement" of
the relevant provision of Part 1, these changes are made to the relevant text of Part 1. Where
no change is necessary, the words "This clause of Part 1 is applicable" are used. When a
particular subclause of Part 1 is not mentioned in this part, that subclause applies as far as is
reasonable.
Additional specific provisions to those in Part 1, given as individual clauses or subclauses, are
numbered starting from 101.
NOTE The following numbering system is used:
– subclauses, tables and figures that are numbered starting from 101 are additional to those in Part 1;
– unless notes are in a new subclause or involve notes in Part 1, they are numbered starting from 101, including
those in a replaced clause or subclause;
– additional annexes are lettered AA, BB, etc.
In this standard, the following print types are used:
– requirements and definitions: in roman type;
– NOTES: in smaller roman type;
– terms used throughout this standard which have been defined in Clause 3: in bold type.

– 8 – IEC 60519-4:2021 © IEC 2021
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under webstore.iec.ch in the data related to the
specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The "colour inside" logo on the cover page of this document indicates that it
contains colours which are considered to be useful for the correct understanding of its
contents. Users should therefore print this document using a colour printer.

INTRODUCTION
This fifth edition of IEC 60519-4 is a product safety publication and is intended to:
– include all types of installations or equipment that are in the scope of IEC TC 27/MT 21
dealing with arc furnace installations;
– give requirements on electrical safety, touch currents, electric fields, magnetic fields and
radiation;
– give means for verification of the requirements;
– make extensive use of the standards developed by IEC committees with horizontal or
group safety functions and of relevant ISO standards, most of them being developed by
ISO TC 244;
– include all material, references and requirements suitable for risk assessment and list of
significant hazards.
This document addresses mainly manufacturers making made-to-order equipment on a
single project base. The manufacturer is well aware that it is his responsibility to make
equipment safe through adequate risk reduction and it is the responsibility of the user to assess
exposure of the operator in line with applicable health and safety regulations. Looking at
projects providing single pieces of equipment or single installations, this clear division of
responsibilities tends to blur, caused by inter alia:
– development of the process (normal operation) through the manufacturer and user,
– shared definition of working procedures for the operator by the manufacturer and user,
– the scope of delivery often including all protective means,
– individual sales contracts where users require an assessment of exposure through the
manufacturer.
Thus, this document provides information on electrical hazards and limits where relevant,
despite being well aware that this is exceeding the scope of a product standard.
Annexes I and J provide orientation with respect to the application of ISO 13577-1 in
combination with this document.
The rated voltage of an arc furnace Installation can be in the range of low voltage or high
voltage; details are given in 4.2.
This document presumes that the installation or equipment is operated and maintained only by
personnel consisting of skilled or instructed persons.
This document is intended for verifying whether the arc furnace installation meets the safety
requirements of this document through design, site acceptance tests, routine tests or inspection.

– 10 – IEC 60519-4:2021 © IEC 2021
SAFETY IN INSTALLATIONS FOR ELECTROHEATING
AND ELECTROMAGNETIC PROCESSING –

Part 4: Particular requirements for arc furnace installations

1 Scope
This clause of Part 1 is replaced by the following.
Replacement:
This part of IEC 60519 provides particular safety requirements for arc furnace installations. This
document deals with the significant hazards, hazardous situations or hazardous events relevant
to industrial arc furnace installations, as listed in Annex A, for normal operation and for single
fault condition as well as under conditions of reasonably foreseeable misuse.
This document specifies the requirements intended to be met by the manufacturer to ensure
the safety of persons and property during the complete life cycle of the equipment from design
through commissioning, operation, maintenance, inspection, to decommissioning, as well as in
the event of foreseeable single fault condition that can occur in the equipment.
The rated voltage of arc furnace installation can be in the range of low voltage or high voltage,
details are given in 4.2.
This standard is applicable to arc furnace installations such as:
a) furnaces for direct arc heating, forming arcs between the electrode and metal such as the
electric arc furnace using alternating current (EAF AC) or direct current (EAF DC), and the
ladle furnace (LF);
b) furnaces for arc-resistance heating forming arcs between the electrode and the charge
material or heating the charge material by the Joule effect, such as the submerged arc-
resistance furnace using alternating current (SAF AC), or direct current (SAF DC).
NOTE 1 In some documents, the terms "smelter" or "electrical reduction furnace" are used.
Furnace installation for unattended operation is not covered by this document.
This document does not provide requirements for type testing.
NOTE 2 Industrial equipment covered by this document is typically produced as a single unit or a very small number
of units; such unit usually has a very high value and can cause severe harm at disintegration.
This document does not address data security and hazards arising from neglect of security.
With respect to noise of electrical an arc furnace, ISO 13578:2017, 6.1.23 applies.
EAF DC and SAF DC are classified as zero frequency (0 Hz) equipment types. EAF AC, SAF
AC and LF are classified as mains frequency (50 Hz or 60 Hz) equipment types. Furnaces being
operated at frequencies outside of the above-mentioned equipment types are not covered by
this document.
2 Normative references
This clause of Part 1 is applicable except as follows.

Replacement:
IEC 61936-1:2021, Power installations exceeding 1 kV AC and 1,5 kV DC - Part 1: AC
Additions:
IEC 60060-3, High-voltage test techniques – Part 3: Definitions and requirements for on-site
testing
IEC 60519-1:2020, Safety in installations for electroheating and electromagnetic processing –
Part 1: General requirements
ISO 13577-1:2016, Industrial furnaces and associated processing equipment – Safety – Part 1:
General requirements
ISO 13578:2017, Industrial furnaces and associated processing equipment – Safety
requirements for machinery and equipment for production of steel by electric arc furnaces
3 Terms, definitions and abbreviated terms
3.1 General concepts
This subclause of Part 1 is applicable with the following additions.
Addition:
NOTE General definitions can be found in the IEC 60050 series, International Electrotechnical Vocabulary.
Terms relating to industrial electro heating are defined in IEC 60050-841. Terms relating to EAF and SAF are
also defined in IEC 60676 and IEC 60683.
3.1.101
intended use
use of a machine in accordance with the information for use provided in the instructions
[SOURCE: ISO 12100:2010, 3.23]
3.2 Equipment and state of equipment
This subclause of Part 1 is applicable with the following additions.
Addition:
3.2.101
AC current converter
device, which controls the secondary alternating current for EAF or SAF
3.2.102
arc furnace
furnace with a vessel, in which metal or other charged conducting material is heated mainly by
electric arc or joule effect using alternating current (AC) or direct current (DC)
[SOURCE: IEC 60050-841:2004, 841-26-05, modified – The definition has been entirely
reworded for better accuracy.]

– 12 – IEC 60519-4:2021 © IEC 2021
3.2.103
arc furnace transformer
transformer changing high voltage electrical supply to a lower voltage and higher current for
an arc furnace process
[SOURCE: IEC 60050-841:2004, 841-26-55, modified – The definition has been entirely
reworded for better accuracy.]
3.2.104
electric arc furnace using alternating current
EAF AC
furnace, in which electric arcs between the electrodes and conducting material are formed,
using alternating current
[SOURCE: IEC 60050-841:2004, 841-26-07, modified – The term has been modified and the
definition has been entirely reworded for better accuracy.]
3.2.105
electric arc furnace using direct current
EAF DC
furnace, in which the direct current is conducted via bottom electrode(s) (anode) to the
material to be processed, forming arcs between the material and the electrode(s) from top
(cathode)
[SOURCE: IEC 60050-841:2004, 841-26-06, modified – The term has been modified and the
definition has been entirely reworded for better accuracy.]
3.2.106
EAF electrode
LF electrode
part produced from high density graphite to transfer the electrical energy forming arcs between
tip and charged material
[SOURCE: IEC 60050-841:2004, 841-26-38, modified – The terms and the definition have been
made specific to EAF and LF.]
3.2.107
electrode clamp
metallic, water cooled device to hold the electrode and supply current for arcing to the
electrode
[SOURCE: IEC 60050-841:2004, 841-26-39]
3.2.108
ladle furnace
LF
arc furnace for secondary treatment of liquid metals which uses a ladle instead of a furnace
vessel
[SOURCE: IEC 60050-841:2004, 841-26-10, modified – The abbreviated term "LHF" has been
removed and the definition has been entirely reworded for better accuracy.]
3.2.109
rectifier for direct current
device which converts alternating current into direct current for EAF DC or SAF DC

3.2.110
submerged arc-resistance furnace
SAF
furnace, in which material melting is carried out as a result of combined arc and resistance
heating
[SOURCE: IEC 60050-841:2004, 841-26-12, modified – The word "charge" has been replaced
by "material".]
3.2.111
submerged arc-resistance furnace using alternating current
SAF AC
furnace, in which material melting is carried out as a result of combined arc and resistance
heating, using alternating current
3.2.112
submerged arc-resistance furnace using direct current
SAF DC
furnace, in which material melting is carried out as a result of combined arc and resistance
heating, using direct current
3.2.113
SAF electrode
part produced from conductive material to transfer the electric current to the process
Note 1 to entry: There are different types of SAF electrodes, i.e.:
a) prebaked electrodes,
b) self-baking electrodes (e.g. Soederberg electrodes),
c) extrusion/composite electrodes, which are a combination of Soederberg electrodes with a prebaked electrode as
a core,
d) hollow electrode system, which allow charging of fines via the centre hole (prebaked, self-baking).
3.2.114
single fault condition
condition in which there is a fault of a single protection (but not a reinforced protection) or of a
single component or device .
Note 1 to entry: If a single fault condition results in one or more other fault conditions, all are considered as one
single fault condition.
Note 2 to entry: Reinforced protection is defined in IEC 60050-903:2013, 903-02-08.
[SOURCE: IEC GUIDE 104:2019, 3.8]
3.2.115
furnace ON of an arc furnace installation
normal arc furnace conditions during status "furnace breaker ON" and disconnector CLOSE and
grounding switch OPEN
3.2.116
furnace OFF of an arc furnace installation
normal arc furnace conditions during status "furnace breaker OFF" and disconnector CLOSE
and grounding switch OPEN
3.2.117
furnace shut down of an arc furnace installation
normal arc furnace condition during status "furnace breaker OFF" and disconnector OPEN and
grounding switch CLOSED
– 14 – IEC 60519-4:2021 © IEC 2021
3.3 Parts and accessories
This subclause of Part 1 is applicable.
3.4 Safety related concepts
This subclause of Part 1 is applicable with the following addition.
Addition:
3.4.101
emergency stop matrix
matrix indicating the relation of locations of emergency stop devices and related safety functions
3.5 Abbreviated terms
This subclause of Part 1 is applicable with the following addition.
Addition:
DRI: Direct reduced iron
EBT: Eccentric bottom tapping
HBI: Hot briquetted iron
OBT: Oval bottom tapping
4 Classification and subdivision of equipment and installations
4.1 Classification by processing frequency
This subclause of Part 1 is applicable.
4.2 Classification by voltage
This subclause of Part 1 is applicable with the following additions:
Additions:
Arc furnaces can be operated with a secondary voltage above 1 000 V (rms) at mains
frequency or 1 500 V direct current; state of technology are arc furnaces with a secondary
voltage of up to 3 600 V (rms) at mains frequency or 5 000 V DC.
High current supply part of arc furnaces with the secondary voltage up to 3 600 V (rms) or up
to 5 000 V DC shall exceptionally be handled according to LV requirements, taking into account
special requirements mentioned in this document.
NOTE High current supply part starting from the secondary side terminals of the arc furnace transformer mainly
consist of secondary outlets of the arc transformer, high current bus bars, high current cables, flexibles, electrode
support arms, electrode columns, electrodes and where applicable AC current converter, rectifier for direct
current, reactor and/or bottom anode.
4.3 Subdivision of installation and equipment
This subclause of Part 1 is applicable.
4.4 Classification of hazards and risks
This subclause of Part 1 is applicable.

5 Risk assessment
This clause of Part 1 is applicable, with the following addition.
Addition:
Due to the different designs of arc furnace installations, an individual risk assessment shall be
carried out in any case, taking into account the specifi
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