Safety in electroheat installations - Part 4: Particular requirements for arc furnace installations

Is applicable to electroheat installations such as furnaces for direct arc heating (direct arc furnaces, submerged arc furnaces, ladle arc heating furnaces) and furnaces for indirect arc heating. The contents of the corrigendum of December 2008 have been included in this copy.

Sicherheit in Elektrowärmeanlagen - Teil 4: Besondere Bestimmungen für Lichtbogenofenanlagen

Sécurité dans les installations électrothermiques - Partie 4: Exigences particulières pour les installations de fours à arc

Est applicable aux installations électrothermiques telles que les fours utilisant le chauffage par arc direct (fours à arc direct, fours à arc submergés, fours poches avec chauffage à l'arc) et les fours à arc indirect. Le contenu du corrigendum de décembre 2008 a été pris en considération dans cet exemplaire.

Varnost pri električnih grelnih inštalacijah - 4. del: Posebne zahteve za inštalacije obločnih peči (IEC 60519-4:2006)

General Information

Status
Withdrawn
Publication Date
21-Sep-2006
Current Stage
6060 - Document made available
Due Date
22-Sep-2006
Completion Date
22-Sep-2006

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---------------------- Page: 1 ----------------------
EUROPEAN STANDARD
EN 60519-4
NORME EUROPÉENNE
September 2006
EUROPÄISCHE NORM
ICS 25.180.10 Supersedes EN 60519-4:1997 + A1:2000
English version
Safety in electroheat installations
Part 4: Particular requirements
for arc furnace installations
(IEC 60519-4:2006)
Sécurité dans les installations Sicherheit in Elektrowärmeanlagen
électrothermiques Teil 4: Besondere Bestimmungen
Partie 4: Exigences particulières für Lichtbogenofenanlagen
pour les installations de fours à arc (IEC 60519-4:2006)
(CEI 60519-4:2006)

This European Standard was approved by CENELEC on 2006-09-01. 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 Central Secretariat 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 Central Secretariat has the same status as the official versions.

CENELEC members are the national electrotechnical committees of Austria, Belgium, 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 and the United Kingdom.
CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
Central Secretariat: rue de Stassart 35, B - 1050 Brussels

© 2006 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.

Ref. No. EN 60519-4:2006 E
---------------------- Page: 2 ----------------------
EN 60519-4:2006 - 2 -
Foreword

The text of document 27/528/FDIS, future edition 3 of IEC 60519-4, prepared by IEC TC 27, Industrial

electroheating equipment, was submitted to the IEC-CENELEC parallel vote and was approved by

CENELEC as EN 60519-4 on 2006-09-01.
This European Standard supersedes EN 60519-4:1997 + A1:2000.
It includes the following significant changes with respect to EN 60519-4:1997:
– the structure has been adjusted to that of EN 60519-1:2003;

– the classification takes into account the special definition of "band 2" for arc furnaces and the

possibility of band 3 equipment;

– additional provisions concerning the impact of electromagnetic effects have been introduced (in 6.4).

This part of EN 60519 shall be read in conjunction with EN 60519-1:2003. It is intended to modify, replace

or make additions to EN 60519-1 for particular requirements concerning arc furnace installations.

The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2007-06-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2009-09-01
Annex ZA has been added by CENELEC.
__________
Endorsement notice

The text of the International Standard IEC 60519-4:2006 was approved by CENELEC as a European

Standard without any modification.
__________
---------------------- Page: 3 ----------------------
- 3 - EN 60519-4:2006
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications

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.

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 60050-841 2004 International electrotechnical vocabulary - -
Part 841: Industrial electroheat
IEC 60073 2002 Basic and safety principles for man-machine EN 60073 2002
interface, marking and identification - Coding
principles for indicators and actuators

IEC 60204-1 (mod) 2005 Safety of machinery - Electrical equipment of EN 60204-1 2006

machines
Part 1: General requirements
IEC 60364-4-41 2005 Low-voltage electrical installations - -
Part 4-41: Protection for safety - Protection
against electric shock
IEC 60364-4-43 2001 Electrical installations of buildings - -
Part 4-43: Protection for safety - Protection
against overcurrent
IEC/TS 60479-1 2005 Effects of current on human beings and - -
livestock
Part 1: General aspects
IEC 60519-1 2003 Safety in electroheat installations EN 60519-1 2003
Part 1: General requirements
CISPR 11 (mod) - Industrial scientific and medical (ISM) radio-- -
frequency equipment - Electromagnetic
disturbance characteristics - Limits and
methods of measurement
Undated reference.
---------------------- Page: 4 ----------------------
NORME CEI
INTERNATIONALE
IEC
60519-4
INTERNATIONAL
Troisième édition
STANDARD
Third edition
2006-08
Sécurité dans les installations électrothermiques –
Partie 4:
Exigences particulières pour les installations
de fours à arc
Safety in electroheat installations –
Part 4:
Particular requirements for arc furnace
installations
 IEC 2006 Droits de reproduction réservés  Copyright - all rights reserved

Aucune partie de cette publication ne peut être reproduite ni No part of this publication may be reproduced or utilized in any

utilisée sous quelque forme que ce soit et par aucun procédé, form or by any means, electronic or mechanical, including

électronique ou mécanique, y compris la photocopie et les photocopying and microfilm, without permission in writing from

microfilms, sans l'accord écrit de l'éditeur. the publisher.

International Electrotechnical Commission, 3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, Switzerland

Telephone: +41 22 919 02 11 Telefax: +41 22 919 03 00 E-mail: inmail@iec.ch Web: www.iec.ch

CODE PRIX
PRICE CODE
Commission Electrotechnique Internationale
International Electrotechnical Commission
МеждународнаяЭлектротехническаяКомиссия
Pour prix, voir catalogue en vigueur
For price, see current catalogue
---------------------- Page: 5 ----------------------
60519-4  IEC:2006 – 3 –
CONTENTS

FOREWORD...........................................................................................................................5

1 Scope...............................................................................................................................9

2 Normative references .......................................................................................................9

3 Terms and definitions .......................................................................................................9

4 Classification of electroheat equipment according to voltage bands................................11

5 Classification of electroheat equipment according to frequency bands............................11

6 General requirements .....................................................................................................11

7 Isolation and switching ...................................................................................................15

8 Connections to the supply network .................................................................................15

9 Protection against electric shock ....................................................................................17

10 Protection against overcurrent........................................................................................17

11 Equipotential bonding .....................................................................................................19

12 Control circuits and control functions ..............................................................................19

13 Protection against thermal influences .............................................................................19

14 Risk of fire and danger of explosion................................................................................19

15 Marking, labelling and technical documentation ..............................................................19

16 Information on inspection and commissioning, and instructions for utilization and

maintenance of arc furnace installations.........................................................................19

17 Design requirements ......................................................................................................23

18 Protection against overvoltage .......................................................................................29

Annex A (normative) Systems assuring improved safety to personnel working in the

vicinity of electrodes and other live parts of secondary circuit ...............................................31

Annex B (normative) Additional requirements for the safety of non-electrical

components of furnace installations ......................................................................................35

---------------------- Page: 6 ----------------------
60519-4  IEC:2006 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
SAFETY IN ELECTROHEAT INSTALLATIONS –
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 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 provides no marking procedure to indicate its approval and cannot be rendered responsible for any

equipment declared to be in conformity with an IEC Publication.

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 60519-4 has been prepared by IEC technical committee 27:

Industrial electroheating equipment.

This third edition cancels and replaces the second edition published in 1995 as well as its

amendment 1 (2000) and constitutes a technical revision.

This edition includes the following significant changes with respect to the previous edition.

– The structure has been adjusted to that of IEC 60519-1:2003.

– The classification takes into account the special definition of "band 2" for arc furnaces and

the possibility of band 3 equipment.

– Additional provisions concerning the impact of electromagnetic effects have been

introduced (in 6.4).
---------------------- Page: 7 ----------------------
60519-4  IEC:2006 – 7 –

This part of IEC 60519 shall be read in conjunction with IEC 60519-1:2003. It is intended to

modify, replace or make additions to IEC 60519-1 for particular requirements concerning arc

furnace installations.
The text of this standard is based on the following documents:
FDIS Report on voting
27/528/FDIS 27/544/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 list of all parts of the IEC 60519 series, under the general title Safety in electroheat

installations, can be found on the IEC website.

NOTE If necessary, additional parts covering particular industrial electroheat equipment may be prepared.

The committee has decided that the contents of this publication will remain unchanged until

the maintenance result 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.
---------------------- Page: 8 ----------------------
60519-4  IEC:2006 – 9 –
SAFETY IN ELECTROHEAT INSTALLATIONS –
Part 4: Particular requirements for
arc furnace installations
1 Scope
This part of IEC 60519 is applicable to electroheat installations such as:

– furnaces for direct arc heating such as direct arc furnaces, submerged arc furnaces, ladle

arc heating furnaces;
– furnaces for indirect arc heating.

NOTE When the electrodes of an arc furnace deliver a direct current, the arc furnace is called "d.c. arc furnace"

(IEV 841-26-06).
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 60050-841:2004, International Electrotechnical Vocabulary (IEV) – Part 841: Industrial

electroheat

IEC 60073:2002, Basic and safety principles for man-machine interface, marking and

identification – Coding principles for indicators and actuators

IEC 60204-1:2005, Safety of machinery – Electrical equipment of machines – Part 1: General

requirements

IEC 60364-4-41:2005, Low-voltage electrical installations – Part 4-41: Protection for safety –

Protection against electric shock

IEC 60364-4-43:2001, Electrical installations of buildings – Part 4-43: Protection for safety –

Protection against overcurrent

IEC 60479-1:2005, Effects of current on human beings and livestock – Part 1: General

aspects

IEC 60519-1:2003, Safety in electroheat installations – Part 1: General requirements

CISPR 11, Industrial, scientific and medical (ISM) radio-frequency equipment –
Electromagnetic disturbance characteristics – Limits and methods of measurement
3 Terms and definitions

For the purposes of this document, the terms and definitions given in IEC 60519-1 and

IEC 60050-841 apply.
---------------------- Page: 9 ----------------------
60519-4  IEC:2006 – 11 –
4 Classification of electroheat equipment according to voltage bands
The requirements of Clause 4 of IEC 60519-1 apply, except as follows:
4.1 Addition:

The voltage band is determined by the line-to-line open-circuit rated supply voltage to the

electrodes.
4.2.2 Addition:

Direct arc furnaces shall be classified under voltage band 2, even if their rated voltage

exceeds 1 000 V a.c. (1 500 V d.c.) but does not exceed 1 500 V a.c. (2 100 V d.c.).

This is under the precondition that

a) the electrical power installations with a rated voltage above 1 000 V a.c. (1 500 V d.c.),

which are located in enclosed operating premises, have been designed in accordance with

the relevant standards;

b) the envisaged measures and auxiliary equipment according to 15.3 fulfil the requirements

of the actual nominal voltage;

c) the insulation of the high-current conductors to the ground fulfils the minimum

requirements of the relevant standards.
5 Classification of electroheat equipment according to frequency bands
The requirements of Clause 5 of IEC 60519-1 apply, except as follows:
5.1 Addition:

As far as electromagnetic disturbance characteristics are concerned, d.c. is classified as zero

frequency.
6 General requirements

The requirements of Clause 6 of IEC 60519-1 and Annex B of this part of IEC 60519 apply,

except as follows:
6.1.1 Replacement:
Replace the third paragraph by the following:

For voltage band 2 exceeding 1 000 V a.c. and voltage band 3 not exceeding 3 600 V a.c. or

5 000 V d.c., insulation distances along surfaces and/or in air shall take into account the

ionization phenomena which may occur, at high temperatures in high electric fields, in case of

metallic vapour emission, splashes, pollution, etc.
---------------------- Page: 10 ----------------------
60519-4  IEC:2006 – 13 –
6.1.3 Replacement:

Sufficient mechanical stability of the furnace even without a refractory lining shall be ensured.

In the case of rectangular submerged arc furnaces where refractory lining is needed to obtain

mechanical stability, the design shall be such that adjustments in accordance with furnace

expansion are possible.

The operating devices shall be arranged within easy and safe reach of the operator or

operators at his or their normal positions, as far as practicable.

The operating devices shall be designed and placed to prevent their unintended activation, as

far as practicable. Operating devices designed for plug connection shall have connectors that

are mechanically lockable and which do not match with supply network connectors.
6.1.5 Replacement:

Utility supply hoses (for water, hydraulic liquid, etc.) shall not be subjected to undue

mechanical overstressing during movement of the installation.
6.2.1 Replacement:

Electrical equipment installed near components with high operating temperatures shall have

sufficient thermal strength and sufficient protection.
6.2.3 Replacement:

Precautions shall be taken to avoid any hazard to persons due to transient voltages which

might occur during normal operation in circuits comprising transformers, inductors, capacitors

and rectifiers. Equipment shall be designed to suppress and/or withstand the very high

voltages which are normal in the operation of an arc furnace.
6.2.6 Replacement:

The electrical equipment shall be so arranged that it does not deteriorate in normal operation

due to physical and chemical effects, such as those due to heat from the surroundings,

spatter of melted materials and salts, humidity, oil, shocks, friction or electromagnetic forces

created by the operating current. If necessary, suitable measures shall be taken, for example

by providing gutters or protective channels.
6.3.2 Replacement:

Similar precautions shall also be taken concerning the effects of electromagnetic leakage

(stray fields), for example, eddy currents and induced voltages, as far as practicable.

6.4.1 Replacement:

Electromagnetic disturbances created by arc furnaces shall be within the limits given by

CISPR 11, as far as it applies to safety.
---------------------- Page: 11 ----------------------
60519-4  IEC:2006 – 15 –
Add the following new subclause:

6.4.6 For d.c. arc furnaces, measures shall be taken to avoid the influence of strong d.c.

magnetic field on some electrical devices, for example, video display units, control units,

electromagnetic valves, sensors; the magnetization of some steel-made parts shall be

considered.
6.6 Addition:

This also applies to other water-cooled elements, for example, bottom electrodes at d.c. arc

furnaces (see also 16.4.7).
6.6.6 Addition:
– minimum and maximum inlet pressure.
7 Isolation and switching
The requirements of Clause 7 of IEC 60519-1 apply, except as follows:
Add the following new subclauses:

7.3 Emergency-off operating devices shall be clearly marked in red in accordance with

IEC 60073. The colour of the area under the handle at the place of installation shall be

contrasting yellow to make the handle clearly visible. The actuating elements of the

emergency-off operating devices shall be located outside the danger area and easily

accessible to the personnel.

7.4 Before access is gained to the top of furnace or before working in the vicinity of the

electrodes, including the bottom electrodes of a d.c. arc furnace or other conductive parts, is

allowed, an isolating and/or earthing procedure as listed in Annex A shall be carried out.

Means shall be provided to prevent inadvertent re-establishment of the circuit.

7.5 For buck-boost supply systems (see Figure A.3) special care shall be taken to ensure

that the place on which operators stand during work on the electrodes, is connected to the

earthing point of the low-voltage short-circuiting and earthing devices as safely and solidly as

possible.

Special indicators for current and voltage shall trip the high-voltage circuit-breaker at any fault

of the system during the condition furnace OFF to ensure that the current-time-function C1

according to IEC 60479-1 will be not exceeded.

7.6 As far as practicable, all controls associated with the furnace shall be designed to be

"fail-safe". The emergency-off function shall be independent of electronic components as far

as practicable.
8 Connections to the supply network
The requirements of Clause 8 of IEC 60519-1 apply.
---------------------- Page: 12 ----------------------
60519-4  IEC:2006 – 17 –
9 Protection against electric shock
The requirements of Clause 9 of IEC 60519-1 apply, except as follows:
9.1 Addition:

To installations of voltage band 3, relevant national standards shall apply until further notice.

Protection against electric shock shall be provided under the conditions described in 4.2.2.

Add the following new subclause:

9.2.3 Direct contacts with live parts shall not be permissible. However, certain operating

procedures agreed with the local authorities may allow contacts with live parts with the use of

special equipment and tools designed for this purpose.
9.3.2 Replacement:

To ensure safe operation with a view to indirect contacts, solely those requirements of

IEC 60364-4-41 relating to IT earthing systems are applicable.
9.4 Replacement:

At the arc furnace, all accessible metal parts, which are liable to become live accidentally in

the event of an insulation fault, shall be connected electrically as safely and solidly as

possible, by the shortest possible path, to an earth terminal or to an earth contact of the

connector plug.
10 Protection against overcurrent
The requirements of Clause 10 of IEC 60519-1 apply, except as follows:
Replacement:

Where relevant, protective measures against overcurrent shall be provided in accordance with

IEC 60364-4-43 and IEC 60204-1.

Where necessary, protective measures against overcurrent (overloads and short circuits) shall

be provided, even if in excess of the scope specified in these standards.
NOTE IEC 60364-4-43 refers to the protection of cables and wiring up to 1 000 V.
Add the following new subclauses:

10.1 The switching device used for connecting the electroheat installation to the power

supply shall be capable of safely switching off all currents that may occur, including fault

currents.

When two switches are in series then in combination, they shall be capable of safely carrying

and switching off all currents that may arise, including fault currents.

10.2 Protection against overcurrent shall be provided under additional consideration of the

requirements given in 4.2.2.
---------------------- Page: 13 ----------------------
60519-4  IEC:2006 – 19 –
11 Equipotential bonding
The requirements of Clause 11 of IEC 60519-1 apply, except as follows:
Add the following new subclause:
11.4.3 The tilt tracks shall not be used as return circuits.
12 Control circuits and control functions
The requirements of Clause 12 of IEC 60519-1 apply.
13 Protection against thermal influences
The requirements of Clause 13 of IEC 60519-1 apply.
14 Risk of fire and danger of explosion
The requirements of Clause 14 of IEC 60519-1 apply.
15 Marking, labelling and technical documentation
The requirements of Clause 15 of IEC 60519-1 apply, except as follows:
15.1.1 Addition:

l) identification of the principal connections (for example, reference number of a drawing

showing the principal circuit of the furnace).
Add the following new subclause:

15.2.5 The preferred location of the nameplate is on the main furnace control panel.

Wherever there is significant change in the details in any part of the installation, then the

nameplate shall be updated.
15.3 Addition:

Moreover, function descriptions, operating instructions and circuit diagrams as well as

maintenance instructions for the components of the electroheat installation shall be made

available in the case of arc furnace installations. The language used for this documentation

shall be agreed between the manufacturer and the user.

Unless agreed otherwise, the documents shall be in the language of the country in which the

equipment is to be installed.
16 Information on inspection and commissioning, and instructions for
utilization and maintenance of arc furnace installations
The requirements of Clause 16 of IEC 60519-1 apply, except as follows:
---------------------- Page: 14 ----------------------
60519-4  IEC:2006 – 21 –
Add the following new subclauses:

16.1.3 Details of electrical isolation shall be laid down in separate instructions. These shall

be in the form of post-up notices placed in the switching area and/or a set of instructions

given to appropriate personnel for which acknowledgment is obtained.

16.3.4 All personnel shall wear protective clothing, appropriate underwear and other

protectors suitable for their work at the furnace, such as:
• protective boots;
• fire-resistant protective helmets (non-electrically conducting);
• face protections (such as visors and tinted glasses);
• ear protection;
• aprons;
• thermally insulated gloves;
• tinted goggles.

For the selection of tinted goggles at d.c. arc furnaces, the highest intensity of the d.c. arc

shall be considered.

16.3.5 Access to current-carrying parts of the furnace, including the bottom electrode system

of a d.c. arc furnace, shall not be permitted except for specially instructed personnel.

16.3.6 The personnel shall be warned of possible hazards associated with the furnace. In

addition, they shall be warned against gaining access to any hazardous area under the

furnace and the area of current carrying conductors by warning notices. Access to the

hazardous areas shall be prevented by barriers as far as practicable.

16.3.7 All work on the furnace concerned with the unclamping and reclamping, changing and

joining of electrodes and work on electrode accessories shall not be carried out unless

protective measures as stated in 7.4 have been carried out. This also applies for automatic

electrode joining.

16.3.8 Deviations from the requirement of 16.3.7 are permitted if safety of the personnel is

fully ensured by other suitable precautions (for example, insulation of the place on which

operators stand, safe distance, use of insulated tools, contacts with only one electrode).

16.3.9 If the furnace is energized, tools, oxygen lances, lances for bath temperature

measuring and other metallic devices shall be effectively earthed or, when possible, their

accessible metal parts shall be insulated or shall only be used by personnel insulated from

earth. Where practicable, the lengths o
...

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