SIST EN 60676:2012

SLOVENSKI STANDARD
01-maj-2012
2SUHPD]DLQGXVWULMVNRHOHNWULþQRRJUHYDQMH3UHVNXVQHPHWRGH]DSHþL]
RGNULWLPREORNRP
Industrial electroheating equipment - Test methods for direct arc furnaces
Industrielle Elektrowärmeanlagen - Prüfverfahren für Lichtbogen-Schmelzöfen
Chauffage électrique industriel - Méthodes d'essai des fours à arc direct
Ta slovenski standard je istoveten z: EN 60676:2012
ICS:
25.180.10 (OHNWULþQHSHþL Electric furnaces
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD
EN 60676
NORME EUROPÉENNE
February 2012
EUROPÄISCHE NORM
ICS 25.180.10 Supersedes EN 60676:2002

English version
Industrial electroheating equipment -
Test methods for direct arc furnaces
(IEC 60676:2011)
Chauffage électrique industriel -  Industrielle Elektrowärmeanlagen -
Méthodes d'essai des fours à arc direct Prüfverfahren für Lichtbogen-Schmelzöfen
(CEI 60676:2011) (IEC 60676:2011)

This European Standard was approved by CENELEC on 2011-12-13. 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, France, Germany, Greece, Hungary, Iceland, Ireland, Italy,
Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia,
Spain, Sweden, Switzerland, Turkey and the United Kingdom.

CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung

Management Centre: Avenue Marnix 17, B - 1000 Brussels

© 2012 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 60676:2012 E
Foreword
The text of document 27/816/FDIS, future edition 3 of IEC 60676, prepared by IEC/TC 27 "Industrial
electroheating" was submitted to the IEC-CENELEC parallel vote and approved by CENELEC as
The following dates are fixed:
(dop) 2012-09-13
• latest date by which the document has
to be implemented at national level by
publication of an identical national
standard or by endorsement
• latest date by which the national (dow) 2014-12-13
standards conflicting with the
document have to be withdrawn
This document supersedes EN 60676:2002.
– Clause 1 (Scope and object) – types of furnaces are more clearly defined.
– Clause 2 (Normative references) and Clause 3 (Terms and definitions) have been updated and
completed.
– New Clause 4 (Features of the EAFsystem) has been added; it mainly concentrates on the tests
necessary for high-voltage / high-current electrical equipment in the installation.
– Clause 5 (Type of tests and general conditions of their performance) and Clause 6 (Technical tests)
have been modified according to today’s requirements for safe operation of an EAF.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC [and/or CEN] shall not be held responsible for identifying any or all such patent
rights.
Endorsement notice
The text of the International Standard IEC 60676:2011 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:
[2] IEC 60146-1-1:2009 NOTE  Harmonized as EN 60146-1-1:2010 (not modified).
[3] IEC 60683:2011 NOTE  Harmonized as EN 60683:2012 (not modified).

- 3 - EN 60676:2012
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

The following documents, in whole or in part, are normatively referenced in this document and are
indispensable for its application. For dated references, only the edition cited applies. For undated
references, the latest edition of the referenced document (including any amendments) applies.

NOTE  When an international publication has been modified by common modifications, indicated by (mod), the relevant EN/HD
applies.
Publication Year Title EN/HD Year

IEC 60398 1999 Industrial electroheating installations - EN 60398 1999
General test methods
IEC 60519-1 - Safety in electroheating installations - EN 60519-1 -
Part 1: General requirements
IEC 60519-4 - Safety in electroheat installations - EN 60519-4 -
Part 4: Particular requirements for arc furnace
installations
IEC 60676 ®
Edition 3.0 2011-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Industrial electroheating equipment – Test methods for direct arc furnaces

Chauffage électrique industriel – Méthodes d’essai des fours à arc direct

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX R
ICS 25.180.10 ISBN 978-2-88912-725-2

– 2 – 60676 © IEC:2011
CONTENTS
FOREWORD . 3
1 Scope and object . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Features of the EAF system . 9
4.1 General . 9
4.2 Electrical assembly of EAF . 9
4.3 Furnace construction . 9
4.4 Water cooling . 10
5 Type of tests and general conditions of their performance . 10
5.1 General . 10
5.2 List of tests during cold and hot state . 10
6 Technical tests . 11
6.1 Electrical insulation of high-current system . 11
6.1.1 General . 11
6.1.2 Insulation resistance . 11
6.2 Cooling water system . 11
6.3 Electrode motion speed . 12
6.4 Short-circuit test procedures. 12
6.4.1 General . 12
6.4.2 High current system: resistance and reactance of EAFac . 12
6.4.3 Test procedures . 12
6.4.4 Asymmetry factor. 16
6.5 Main characteristics of EAF during production . 16
6.5.1 General . 16
6.5.2 Test procedures . 16
6.6 Electrode consumption . 17
6.7 Phase rotation . 18
6.8 EAF – Rated capacity . 18
Bibliography . 19

Figure 1 – Wiring diagram for measuring electrical data of the high current system to
determine the resistance and reactance values . 13

60676 © IEC:2011 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INDUSTRIAL ELECTROHEATING EQUIPMENT –
TEST METHODS FOR DIRECT ARC FURNACES

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 dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60676 has been prepared by IEC technical committee 27:
Industrial electroheating.
This third edition cancels and replaces the previous edition published in 2002 and constitutes
a technical revision.
Significant technical changes with respect to the previous edition are as follows:
– Clause 1 (Scope and object) – types of furnaces are more clearly defined.
– Clause 2 (Normative references) and Clause 3 (Terms and definitions) have been updated
and completed.
– New Clause 4 (Features of the EAFsystem) has been added; it mainly concentrates on the
tests necessary for high-voltage / high-current electrical equipment in the installation.
– Clause 5 (Type of tests and general conditions of their performance) and Clause 6
(Technical tests) have been modified according to today’s requirements for safe operation
of an EAF.
– 4 – 60676 © IEC:2011
The text of this standard is based on the following documents:
FDIS Report on voting
27/816/FDIS 27/837/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
60676 © IEC:2011 – 5 –
INDUSTRIAL ELECTROHEATING EQUIPMENT –
TEST METHODS FOR DIRECT ARC FURNACES

1 Scope and object
This International Standard specifies test procedures, conditions and methods according to
which the main parameters and the main operational characteristics of electric arc furnaces
(EAF) operated either with alternating current (EAFac) or with direct current (EAFdc) with a
capacity above 500 kg/heat are established.
The EAF technology is also applicable to furnaces, in which liquid metal is kept at high
temperature or superheated to casting temperature (e.g. in a ladle furnace (LF), operated with
alternating current).
Test methods for some special equipment, e.g. controlled rectifiers for EAFdc, are covered by
IEC 60146-1-1.
Test methods for submerged arc furnaces (SAF) are covered by IEC 60683.
2 Normative references
The following referenced documents are indispensable for the application 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.
IEC 60398:1999, Industrial electroheating installations – General test methods
IEC 60519-1, Safety in electroheating installations – Part 1: General requirements
IEC 60519-4, Safety in electroheat installations – Part 4: Particular requirements for arc
furnace installations
3 Terms and definitions
For the purposes of this document the terms and definitions given in IEC 60519-1:2010 and
the following apply.
NOTE Refer to International Electrotechnical Vocabulary, IEC 600500, for general definitions. Terms relating to
industrial electroheat are defined in IEC 60050-841.
3.1
active power
P
mean value of the instantaneous power p (in kW) taken under periodic conditions over one
period of time T (in h):
T
P= p dt
∫
T
NOTE Active power instantaneous value (r.m.s.) measured at any time, including all phases.
[IEC 60050-131:2002, 131-11-42, modified]

– 6 – 60676 © IEC:2011
3.2
apparent power
S
power rating of the transformer, energizing the EAF (in MVA)
S= 3 UI (for three-phase EAF)
where
U is the voltage, r.m.s., sinusoidal value [in kV]
I is the current, r.m.s. sinusoidal value [in KA]
[IEC 60050-131:2002, 131-11-41, modified]
3.3
arc furnace
furnace with a vessel, in which a metallic charge is heated mainly by electric arc using
alternating current (EAFac) or direct current (EAFdc)
[IEC 60050-841:2004, 841-26-05, modified]
3.4
arc furnace transformer
transformer changing medium/high voltage electrical supply to low voltage and high current
for an EAF
[IEC 60050-841:2004, 841-26-55, modified]
3.5
asymmetry factor
K
difference between maximum and minimum impedance of any phase, divided by the mean
impedance of all three phases (in %)
NOTE Not applicable for EAFdc.
3.6
capacity (of EAF)
volume of liquid material, which can be produced in the EAF (in t)
NOTE Whether metric or short tonnes according to pre-requisites.
[IEC 60050-841:2004, 841-21-40, modified]
3.7
cold state (of EAF installation)
thermal state of EAF installation when the temperature of all parts equals the ambient
temperature
3.8
electric arc furnace using alternating current
EAFac
furnace, in which electric arcs between the electrodes and the process material are formed,
using three-phase alternating current
NOTE Ladle furnace (LF) is operated under the same conditions.
[IEC 60050-841:2004, 841-26-07, modified]

60676 © IEC:2011 – 7 –
3.9
electric arc furnace using direct current
EAFdc
furnace, in which the direct current is induced via a bottom electrode (anode) to the material
to be processed, forming arcs between the material and the electrode from top (cathode)
[IEC 60050-841:2004, 841-26-06, modified]
3.10
EAF electrode
part produced from high density graphite to transfer the electrical energy forming arcs
between tip and charge material
NOTE In EAFdc, a bottom electrode (anode) is metallic or conductive material in the bottom of an EAF and arcs
are formed between the charge material and the graphite electrode from top (cathode).
[IEC 60050-841:2004, 841-26-38, modified]
3.11
electrode clamp
metallic, water cooled equipment to hold the electrode and supply current for arcing to the
electrode
[IEC 60050-841:2004, 841-26-39, modified]
3.12
heat
mass of liquid material which is tapped after one process from an EAF into a ladle (in t)
3.13
high-current line
assembly to conduct the high current between transformer secondary bushings and
electrode(s) of an EAF
NOTE It consists of the bus bar system, cables and either a current tube system or current conducting electrode
arm to the electrodes.
[IEC 60050-841:2004, 841-26-54, modified]
3.14
hot state (of EAF)
thermal state of an EAF in which the components and charge material are at a temperature
above 600 °C and a steady-state temperature of the components is reached
3.15
medium/high-voltage switchgear
medium/high-voltage switchgear connecting the EAF transformer to the electrical supply by
switching on/off under load
NOTE EAF circuit switchgear capable for up to 150 operations under load per day.
3.16
operational short circuit
short circuit due to direct contact of at least two electrodes in an EAFac with charge/liquid
material
NOTE In EAFdc, short
...