IEC 60974-3:2013

IEC 60974-3 ®
Edition 3.0 2013-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Arc welding equipment –
Part 3: Arc striking and stabilizing devices

Matériel de soudage à l’arc –
Partie 3: Dispositifs d’amorçage et de stabilisation de l’arc

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IEC 60974-3 ®
Edition 3.0 2013-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Arc welding equipment –
Part 3: Arc striking and stabilizing devices

Matériel de soudage à l’arc –
Partie 3: Dispositifs d’amorçage et de stabilisation de l’arc

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX R
ICS 25.160 ISBN 978-2-8322-1199-1

– 2 – 60974-3  IEC:2013
CONTENTS
FOREWORD . 4

1 Scope . 6

2 Normative references . 6

3 Terms and definitions . 6

4 Environmental conditions . 7

5 Tests . 7

5.1 Test conditions . 7

5.2 Measuring instruments . 7
5.3 Conformity of components . 7
5.4 Type tests . 7
5.5 Routine tests. 7
5.5.1 Stand-alone unit . 7
5.5.2 Built-in unit . 8
6 Protection against electric shock . 8
6.1 Insulation . 8
6.1.1 General . 8
6.1.2 Clearances . 8
6.1.3 Creepage distances . 8
6.1.4 Insulation resistance . 9
6.1.5 Dielectric strength . 9
6.2 Protection against electric shock in normal service (direct contact) . 10
6.3 Protection against electric shock in case of a fault condition (indirect
contact) . 10
6.4 Protective provision . 10
7 Thermal requirements . 10
8 Thermal protection . 10
9 Abnormal operation . 10
10 Connection to the supply network . 11
11 Output . 11
11.1 Rated peak voltage . 11
11.2 Impulse current . 12
11.2.1 Risk of electric shock . 12

11.2.2 Electric charge. 12
11.2.3 Direct contact . 12
11.2.4 Series contact. 13
11.3 Mean energy . 14
11.4 Output circuit capacitance discharging . 15
12 Control circuits . 15
13 Hazard reducing device . 15
14 Mechanical provisions . 15
15 Rating plate . 15
16 Adjustment of the output . 16
17 Instructions and markings . 16
17.1 Instructions . 16
17.2 Markings . 17

60974-3  IEC:2013 – 3 –
Annex A (informative) Examples of coupling systems for arc striking and stabilizing

devices . 18

Annex B (informative) Example of a rating plate . 19

Bibliography . 20

Figure 1 – Rated peak voltage . 11

Figure 2 – Measurement of electric charge of impulse current . 12

Figure 3 – Measuring circuit for direct contact . 13

Figure 4 – Measuring circuit for serial contact . 14

Figure 5 – Measurement of mean energy . 14
Figure 6 – Measuring circuit for capacitance discharging . 15
Figure A.1 – Examples of coupling systems for arc striking and stabilizing devices . 18
Figure B.1 – Stand-alone unit . 19

Table 1 – Minimum clearances and creepage distances for arc striking and stabilizing
circuits . 9
Table 2 – Maximum peak voltages . 11

– 4 – 60974-3  IEC:2013
INTERNATIONAL ELECTROTECHNICAL COMMISSION

____________
ARC WELDING EQUIPMENT –
Part 3: Arc striking and stabilizing devices

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,
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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
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4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
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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 60974-3 has been prepared by IEC technical committee 26:

Electric welding.
This third edition cancels and replaces the second edition published in 2007 and constitutes a
technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
– changes induced by the publication of IEC 60974-1:2012.

60974-3  IEC:2013 – 5 –
The text of this standard is based on the following documents:

FDIS Report on voting
26/518/FDIS 26/521/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.

This standard shall be read in conjunction with IEC 60974-1:2012.
The list of all the parts of IEC 60974, under the general title Arc welding equipment, can be
found on the IEC web site.
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.
– 6 – 60974-3  IEC:2013
ARC WELDING EQUIPMENT –
Part 3: Arc striking and stabilizing devices

1 Scope
This part of IEC 60974 specifies safety requirements for industrial and professional arc

striking and arc stabilizing devices used in arc welding and allied processes.
This part of IEC 60974 is applicable to stand-alone units which may be connected to a
separate welding power source or one where the welding power source and the arc striking
and arc stabilizing device are housed in a single enclosure.
NOTE 1 Typical allied processes are for example plasma arc cutting and arc spraying.
NOTE 2 This standard does not include electromagnetic compatibility (EMC) requirements.
2 Normative references
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.
IEC 60974-1:2012, Arc welding equipment – Part 1: Welding power sources
IEC 60974-7, Arc welding equipment – Part 7: Torches
IEC 61140, Protection against electric shock – Common aspects for installation and
equipment
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60974-1 and
IEC 60974-7, as well as the following, apply.
3.1
arc striking device
device which superimposes a voltage on the welding circuit to ignite an arc
3.2
arc stabilizing device
device which superimposes a voltage on the welding circuit to maintain an arc
3.3
arc striking voltage
voltage superimposed on the no-load voltage to ignite an arc
3.4
arc stabilizing voltage
voltage superimposed on the arc voltage to maintain the arc

60974-3  IEC:2013 – 7 –
3.5
arc striking period
period during which the arc striking voltage is superimposed on the no-load voltage

4 Environmental conditions
As specified in IEC 60974-1:2012, Clause 4.

5 Tests
5.1 Test conditions
As specified in 5.1 of IEC 60974-1:2012.
5.2 Measuring instruments
The accuracy of measuring instruments shall be as follows:
a) electrical measuring instruments: class 1 (±1 % of full-scale reading), except for the
measurement of insulation resistance and dielectric strength where the accuracy of the
instruments is not specified, but shall be taken into account for the measurement;
b) thermometer: ±2 K;
c) high-voltage probe: ±5 %.
5.3 Conformity of components
As specified in 5.3 of IEC 60974-1:2012.
5.4 Type tests
As a condition of conformity, the type tests given below shall be carried out on stand-alone
units in the following sequence with no drying time between f), g) and h):
a) general visual inspection, as defined in 3.7 of IEC 60974-1:2012;
b) insulation resistance, as specified in 6.1.4 of IEC 60974-1:2012 (preliminary check);
c) enclosure, as specified in 14.2 of IEC 60974-1:2012;
d) handling means, as specified in 14.3 of IEC 60974-1:2012;
e) drop withstand, as specified in 14.4 of IEC 60974-1:2012;

f) protection provided by the enclosure, as specified in 6.2.1 of IEC 60974-1:2012;
g) insulation resistance, as specified in 6.1.4 of IEC 60974-1:2012;
h) dielectric strength, as specified in 6.1.5 of IEC 60974-1:2012;
i) general visual inspection, as defined in 3.7 of IEC 60974-1:2012.
Rated arc striking and stabilizing peak voltage shall be measured in accordance with 11.1 in
any convenient sequence of type tests but before verifying mechanical provisions.
The other type tests included in this document and not listed here shall be carried out in any
convenient sequence.
5.5 Routine tests
5.5.1 Stand-alone unit
All routine tests shall be carried out on each stand-alone unit in the following sequence:

– 8 – 60974-3  IEC:2013
a) general visual inspection (as defined in 3.7 of IEC 60974-1:2012);

b) continuity of the protective circuit (as specified in Clause 10 and, if applicable, 10.5.1 of

IEC 60974-1:2012);
c) dielectric strength (as specified in 6.1.5 of IEC 60974-1:2012);

d) high-voltage circuit test: working voltage shall be applied to high-voltage circuits to

establish insulation integrity as specified by the manufacturer;

NOTE No-load voltage and connection of the return cable, either to the ground circuit or isolated, affects

working voltage.
e) general visual inspection (as defined in 3.7 of IEC 60974-1:2012).

5.5.2 Built-in unit
The following routine test shall be carried out on each built-in unit in any convenient sequence
for the power source (as specified in 5.5 of IEC 60974-1:2012):
High-voltage circuit test: working voltage shall be applied to high-voltage circuits to
establish insulation integrity as specified by the manufacturer.
NOTE No-load voltage and connection of the return cable, either to the ground circuit or isolated, affects
working voltage.
6 Protection against electric shock
6.1 Insulation
6.1.1 General
As specified in 6.1.1 of IEC 60974-1:2012.
6.1.2 Clearances
The minimum clearances for high-voltage components shall be in accordance with Table 1.
The minimum clearance for other components shall be in accordance with 6.1.2 of
IEC 60974-1:2012.
Conformity shall be checked by measurement and visual inspection.
6.1.3 Creepage distances
The minimum creepage distances for arc striking and stabilizing circuits shall be in
accordance with Table 1. The minimum creepage distances for other components shall be in
accordance with 6.1.3 of IEC 60974-1:2012.

Conformity shall be checked by measurement and visual inspection.

60974-3  IEC:2013 – 9 –
Table 1 – Minimum clearances and creepage distances

for arc striking and stabilizing circuits

a b b
Rated peak voltage Clearance Creepage distance

kV mm mm
3 3 6,3
6 5,5 10
8 8 12,5
10 11 16
12 14 20
15 18 25
18 25 30
20 30 35
NOTE These values apply to circuits which are designed in accordance with 11.3.
a
Rated peak voltage shall be measured in accordance with 11.1.
b
Interpolation is allowed.
6.1.4 Insulation resistance
As specified in 6.1.4 of IEC 60974-1:2012.
6.1.5 Dielectric strength
The output circuit of arc striking and stabilizing devices and the insulation of coupling
components (for example, coupling transformers or coupling capacitors) shall withstand an
arc striking test voltage 20 % higher than the rated peak arc striking voltage at the maximum
pulse repetition rate of the device.
Alternatively, an a.c. test voltage with the same peak value of approximately sine waveform at
50 Hz or 60 Hz may be used for coupling components only. The maximum permissible setting
of the tripping current shall be 100 mA. The high voltage transformer shall deliver the
prescribed voltage up to the tripping current. Tripping is regarded as a flashover or a
breakdown.
NOTE 1 For the operator's safety, the lowest setting of the tripping current (less than or equal to 10 mA) is
typical.
Conformity shall be checked by the following test.

Coupling components intended for use with arc striking and stabilizing voltages shall be
subjected to the arc striking test voltage or the a.c. test voltage for 60 s.
NOTE 2 Interference suppression capacitors are not coupling devices.
The output circuit shall be subjected to the arc striking test voltage for 60 s applied between
the point of connection to the welding electrode and
a) exposed conductive parts;
b) other isolated circuits.
Flashover or breakdown shall not occur. Any discharges unaccompanied by a voltage drop
(corona) are disregarded.
NOTE 2 Interference suppression capacitors are subjected to the test of the output circuit.

– 10 – 60974-3  IEC:2013
6.2 Protection against electric shock in normal service (direct contact)

As specified in 6.2 of IEC 60974-1:2012.

6.3 Protection against electric shock in case of a fault condition (indirect contact)

Stand-alone arc striking and stabilizing device shall be class I or class II equipment in
accordance with IEC 61140, with the exception of the welding circuit.

The output circuit of the arc striking and stabilizing device shall be electrically isolated from
the public supply system by double or reinforced insulation in accordance with the maximum
rated input voltage. Figure A.1 shows examples of coupling systems for arc striking and

stabilizing devices.
Internal conductors and connections shall be secured or positioned as specified in 6.3.3 of
IEC 60974-1:2012.
For Class I stand-alone arc striking and stabilizing device, weighted touch current in the case
of an external protective conductor failure or disconnection shall not exceed the value
specified in 6.3.6 of IEC 60974-1:2012 when energized and not providing the arc striking and
stabilizing voltage.
Conformity shall be checked by visual inspection and by measurement.
6.4 Protective provision
Connection of exposed conductive parts to the protective conductor is not required if the rated
supply voltage is supplied by the welding circuit or SELV.
7 Thermal requirements
Current-carrying components, incorporated in the arc striking and stabilizing device, shall be
capable of carrying the rated welding current as specified by the manufacturer without
a) exceeding the temperature rating of the current-carrying components;
b) causing the surface temperatures, specified in Table 7 of IEC 60974-1:2012, to be
exceeded.
For liquid-cooled apparatus, the test shall be carried out with the minimum flow and the
maximum temperature of the coolant, as recommended by the manufacturer.

Conformity shall be checked by measurement in accordance with 7.2 of IEC 60974-1:2012.
8 Thermal protection
If the arc striking and stabilizing device is designed for use with or built-in a specific welding
power source, the thermal protection tests shall be carried out with the welding power source.
9 Abnormal operation
In the case of a stand-alone arc striking and stabilizing device the abnormal operation tests
defined in Clause 9 of IEC 60974-1:2012 shall be carried out as applicable.
If the arc striking and stabilizing device is designed for use with a specific welding power
source, the abnormal operation tests shall be conducted with the arc striking and stabilizing
device connected to that welding power source.

60974-3  IEC:2013 – 11 –
The arc stabilizing device shall be short circuited at the output, with neither a torch nor a

return cable connected, until equilibrium is achieved.

Arc striking and stabilizing devices protected internally, for example by automatic shut-off,

meet this requirement if the protection device operates before an unsafe condition occurs.

10 Connection to the supply network

As specified in Clause 10 of IEC 60974-1:2012.

11 Output
11.1 Rated peak voltage
The rated peak voltage (U ) is obtained by subtraction of the no-load voltage (U ) from the
p 0
measured peak voltage (see Figure 1). To determine the peak, the voltage shall be measured
across a 220 pF capacitor with neither a torch nor a return cable connected.
When reported on the rating plate of arc striking and stabilizing devices, the rated peak
voltage (U ) shall be equal to or greater than the measured peak voltage, but shall not exceed
p
the maximum values given in Table 2.

U
U
p
U
t
IEC  2836/13
Figure 1 – Rated peak voltage
Table 2 – Maximum peak voltages
Type of torch Peak voltage
Manually guided 15 kV
Mechanically guided or plasma cutting 20 kV

Conformity shall be checked by measurement with an oscilloscope and a high-voltage probe
with sufficient bandwidth.
– 12 – 60974-3  IEC:2013
11.2 Impulse current
11.2.1 Risk of electric shock
Depending on the design of an arc striking and stabilizing device, a risk of electric shock due
to an impulse current can occur under the following situations:

– the human body is in direct contact with the output of the arc striking and stabilizing

device (as specified in 11.2.3);

– the human body is in series with the arc gap as part of the welding circuit (as specified in

11.2.4).
11.2.2 Electric charge
The maximum electric charge in one half-cycle of impulse current, regardless of polarity, shall
not exceed (see Figure 2):
– 8 µC for equipment intended to be used with manually guided torches;
and
– 15 µC for equipment intended to be used with mechanically guided torches and plasma
cutting torches.
The maximum electric charge
I  (A) I  (A)
The maximum electric charge
of impulse current
of impulse current
Q  µC
Q  µC
t  (µs) t  (µs)
IEC  2837/13 IEC  2838/13
a) AC pulse b) DC pulse
Figure 2 – Measurement of electric charge of impulse current
Conformity shall be checked by measurement with an oscilloscope and a high-voltage probe
with sufficient bandwidth.
11.2.3 Direct contact
To simulate the torch capacitance, the value for C shall be
T
– 220 pF for equipment intended to be used with torches or return cables up to 10 m length;
or
– 1 000 pF for equipment intended to be used with torches or return cables above 10 m
length.
To simulate the body resistance, the value of a non-inductive resistor R shall be
B
– 1 kΩ for equipment intended to be used in environments without increased hazard of
electric shock or with a mechanically guided torch;
or
60974-3  IEC:2013 – 13 –
– 500 Ω for equipment intended to be used in environments with increased hazard of electric

shock.
The value of the impulse current is obtained by dividing the value of the measured voltage by

the value of the resistor R .
B
Conformity shall be checked by voltage measurement with an oscilloscope and a high-voltage

probe with sufficient bandwidth, in a circuit as given in Figure 3, with neither a torch nor a

return cable connected.
Key
1 Welding or cutting power source 4 High-voltage probe
2 Arc striking and stabilizing device 5 Load as compact as possible
3 Oscilloscope a Connection lead as short as possible
Figure 3 – Measuring circuit for direct contact
11.2.4 Series contact
The arc gap (6) (see Figure 4) shall be adjusted to the maximum distance at which flashover
consistently occurs.
To simulate the torch capacitance, the value for C shall be
T
– 220 pF for equipment intended to be used with torches or return cables up to 10 m in
length;
or
– 1 000 pF for equipment intended to be used with torches or return cables above 10 m in
length.
shall be
To simulate the body resistance, the value of a non-inductive resistor R
B
– 1 kΩ for equipment intended to be used in environments without increased hazard of
electric shock or with a mechanically guided torch;
or
– 500 Ω for equipment intended to be used in environments with increased hazard of electric
shock.
The value of the impulse current is obtained by dividing the value of the measured voltage by
the value of the resistor R .
B
Conformity shall be checked by voltage measurement with an oscilloscope and a high-voltage
probe with sufficient bandwidth, in a circuit as given in Figure 4, with neither a torch nor a
return cable connected.
– 14 – 60974-3  IEC:2013
Key
1 Welding or cutting power source 5 Load as compact as possible
2 Arc striking and stabilizing device 6 Arc gap
3 Oscilloscope a Connection lead as short as possible
4 High-voltage probe
Figure 4 – Measuring circuit for serial contact
11.3 Mean energy
The mean energy generated by arc striking and stabilizing devices in a non-inductive resistor,
simulating the body resistance shall not exceed during each period of 1 s
– 4 J for equipment intended to be used with manually guided welding torches;
and
– 20 J for equipment intended to be used with mechanically guided and all plasma cutting
torches.
Conformity shall be checked by testing in accordance with 11.2.
Arc striking and stabilizing devices with a mean energy below 4 J are considered as energy
limited for all parts of IEC 60974.
The arc striking and stabilizing voltage is obtained by subtraction of the no-load voltage given
in Table 13 of IEC 60974-1:2012 (see Figure 5).

U
U
t
IEC  2841/13
Figure 5 – Measurement of mean energy

60974-3  IEC:2013 – 15 –
11.4 Output circuit capacitance discharging

One second after the arc striking and stabilizing device output is cut off or disabled, the

output voltage shall not exceed 113 V d.c.

Conformity shall be checked by measurement of the voltage in a circuit as indicated in

Figure 6 by an oscilloscope and a high-voltage probe.

Key
1 Welding or cutting power source 4 High-voltage probe
2 Arc striking and stabilizing device 5 Load as compact as possible
3 Oscilloscope a Connection lead as short as possible
Figure 6 – Measuring circuit for capacitance discharging
To simulate the torch capacitance, the value for C shall be
T
– 220 pF for equipment intended to be used with torches or return cables up to 10 m in
length;
or
– 1 000 pF for equipment intended to be used with torches or return cables above 10 m in
length.
12 Control circuits
As specified in Clause 12 of IEC 60974-1:2012.
13 Hazard reducing device
Not applicable.
14 Mechanical provisions
Only applicable for stand-alone unit as specified in Clause 14 of IEC 60974-1:2012.
15 Rating plate
A clearly and indelibly marked rating plate shall be fixed securely to, or printed on, each
stand-alone arc striking and stabilizing device with the following minimum information (see
Figure 7 and for examples see Figure B.1):
1) name and address of the manufacturer and, if required, distributor, importer, trade mark
and country of origin;
– 16 – 60974-3  IEC:2013
2) type (identification) as given by the manufacturer;

3) traceability of design and manufacturing data, for example, serial number;

4) reference to IEC 60974-3, confirming that the arc striking and stabilizing device conforms

with its requirements;
5) U rated peak voltage;
p
6) X.% duty cycle, if applicable;

7) I rated welding current, if applicable;
8) U rated input voltage(s) and frequency;
9) I rated input current(s) at maximum load;
10) IP. degree of protection, for example, IP21 or IP23;
symbol for protection class II, if applicable.
11)
Conformity shall be checked by visual inspection.
a) Identification
1) 2)
3) 4)
b) Output
5)
6)
6a) 6b) 6c)
X
7) 7a) 7b) 7c)
I
c) Energy input
8) 9)
10) 11)
Optional If applicable
Figure 7 – Rating plate
In the case of an internal arc striking and stabilizing device, box 5 shall be added to the rating
plate of the power source (as specified in Clause 15 of IEC 60974-1:2012).

16 Adjustment of the output
As specified in Clause 16 of IEC 60974-1:2012.
17 Instructions and markings
17.1 Instructions
As specified in 17.1 of IEC 60974-1:2012, with the addition of the following requirement.
The manufacturer shall state in the instructions
– the rated peak voltage;
– if the arc striking and stabilizing device is designed for manual or mechanically guided
operation.
60974-3  IEC:2013 – 17 –
If the use of longer torch or return cables increases the risk of electric shock (limits are

specified in Clause 11) due to an impulse current, the manufacturer shall specify the

maximum length (in m) and a torch type. The following warning shall be given:

Warning: Increasing the length of torch or return cables more than manufacturer maximum

specified length will increase the risk of electric shock.

17.2 Markings
Only applicable for stand-alone units, as specified in 17.2 of IEC 60974-1:2012.

– 18 – 60974-3  IEC:2013
Annex A
(informative)
Examples of coupling systems for arc striking and stabilizing devices

a) b)
c) d)
Key
1 Welding or cutting power source 5 Voltage generator
2 Arc striking and stabilizing device 6 Choke
3 Output 7 Input coupling winding
4 Voltage supply 8 Blocking diode

Figure A.1 – Examples of coupling systems for
arc striking and stabilizing devices

60974-3  IEC:2013 – 19 –
Annex B
(informative)
Example of a rating plate
a) Identification
1) 2)
Manufacturer  Type
3)   4)
Serial number  IEC 60974-3
b) Output
5)
U = 8,5 kV
p
6) 6a) 6b) 6c)
X       35 %        60 %       100 %
7)            7a) 7b) 7c)
I       300 A        220 A       180 A
c) Energy input
8) 9)
U = 230 V          I = 0,5 A
1 1
10) 11)
IP23
Figure B.1 – Stand-alone unit
– 20 – 60974-3  IEC:2013
Bibliography
IEC 60974 (all parts), Arc welding equipment

______________
– 22 – 60974-3  CEI:2013
SOMMAIRE
AVANT-PROPOS . 24

1 Domaine d’application . 26

2 Références normatives . 26

3 Termes et définitions . 26

4 Conditions ambiantes . 27

5 Essais . 27

5.1 Conditions d’essais . 27

5.2 Instruments de mesure . 27
5.3 Conformité des composants . 27
5.4 Essais de type . 27
5.5 Essais individuels de série . 28
5.5.1 Unité indépendante. 28
5.5.2 Unité intégrée . 28
6 Protection contre les chocs électriques . 28
6.1 Isolement . 28
6.1.1 Généralités . 28
6.1.2 Distances dans l’air . 28
6.1.3 Lignes de fuite . 28
6.1.4 Résistance d'isolement . 29
6.1.5 Rigidité diélectrique . 29
6.2 Protection contre les chocs électriques en service normal (contact direct) . 30
6.3 Protection contre les chocs électriques en cas de défaut (contact
indirect) . 30
6.4 Moyen de protection . 30
7 Exigences thermiques . 30
8 Protection thermique . 30
9 Fonctionnement anormal . 31
10 Raccordement au réseau d’alimentation . 31
11 Sortie . 31
11.1 Valeur assignée de la tension de crête. 31
11.2 Courant d’impulsion . 32
11.2.1 Risque de choc électrique. 32

11.2.2 Charge électrique . 32
11.2.3 Courant d'impulsion . 32
11.2.4 Contact de série . 33
11.3 Énergie moyenne . 34
11.4 Déchargement des capacités du circuit de sortie . 35
12 Circuits de commande . 35
13 Dispositif réducteur de risques . 36
14 Dispositions mécaniques . 36
15 Plaque signalétique . 36
16 Réglage de la sortie . 37
17 Instructions et marquage . 37
17.1 Instructions .
...