Iec 60974 8 2009

The gas console can be external or internal to the power source enclosure.. external gas console gas console not incorporated in a power source 3.7 internal gas console gas console inc

Test conditions

As specified in 5.1 of IEC 60974-1.

Measuring instruments

Conformity of components

Type tests

As specified in 5.4 of IEC 60974-1

LICENSED TO MECON Limited - RANCHI/BANGALORE FOR INTERNAL USE AT THIS LOCATION ONLY, SUPPLIED BY BOOK SUPPLY BUREAU.

The other tests included in this standard may be carried out in any convenient sequence.

Routine tests

External gas console

Routine tests for each external gas console must be conducted in a specific order: first, a general visual inspection as outlined in section 3.7 of IEC 60974-1; second, checking the continuity of the protective circuit according to section 10.4.2 of IEC 60974-1; third, performing a dielectric strength test as specified in section 6.1.5 of IEC 60974-1; fourth, conducting a leak test per section 10.3; and finally, repeating the general visual inspection referenced in section 3.7 of IEC 60974-1.

Internal gas console

All routine tests, as specified in 5.5 of IEC 60974-1, shall be carried out on each internal gas console, with the following addition: g) leak test, see 10.3

Insulation

As specified in 6.1 of IEC 60974-1, with the following exception:

Printed circuit boards shall be enclosed, coated, or encapsulated.

Protection against electric shock in normal service (direct contact)

Protection provided by the enclosure

The minimum degree of protection for gas consoles shall be IP21S in accordance with

Conformity is assessed by applying the articulated finger and ball to openings, ensuring no contact with hazardous parts, as outlined in IEC 60529 Additionally, it is essential to verify that the unit meets insulation resistance and dielectric strength tests immediately after the water test, confirming its operational capability.

No power is applied to the unit while performing these tests.

Capacitors

As specified in 6.2.2 of IEC 60974-1.

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

Heating test

For an external gas console, only the relevant tests are performed.

Maximum temperature

The temperature at any point shall not exceed the ignition temperature of any combustible gas intended to be used in the gas console

Conformity must be verified by operating the gas console according to the manufacturer's specifications, utilizing the gas combinations and flow rates that present the worst-case scenario, as outlined by the manufacturer, along with the specified cooling liquid.

8 Connections for plasma cutting torches

As specified in 11.4.6 of IEC 60974-1, where the torch connects to the gas console

As specified in Clause 14 of IEC 60974-1, with the following additions.

Protection against fire or explosion

The gas console shall be designed to prevent fire or explosion under normal operating conditions and under a single-fault condition (for example, defective valve, hose, etc.)

Where a gas console uses a combustible gas, any circuit, subassembly, or component shall not be capable of creating temperatures or a spark with sufficient energy to cause an ignition

Where a gas console uses a combustible gas in a mixture, the mixture shall not be included within flammability limit that is defined by LFL and UFL

Conformity will be verified through two methods: a) evaluating the design and performing calculations on the circuits, subassemblies, or components; or b) applying faults such as open circuits, short circuits, or movement restrictions to the circuits, subassemblies, or components until an event occurs, like a non-igniting spark, a blown fuse, or the unit shutting down, or until a steady-state temperature is reached.

Gas line purging

The gas console must include a purging mechanism for gas lines when switching between different gas types, such as from oxidizing or oxygen-containing gases to combustible gases, to minimize the risk of fire or explosion It is essential that any residual combustible gas or oxygen in the torch remains at a minimal volume to ensure safety and eliminate potential hazards.

The purging shall occur after each change in gas routing or when the previous gas routing is unknown

NOTE 1 A means of accomplishing this can be by purging the lines with a sufficient volume of an inert gas

NOTE 2 When a risk of fire or explosion exists in the gas lines due to changing gas, the purging can be performed with the following pressure cycle:

1 reduce the pressure of the gas console circuit to atmosphere pressure;

2 purge the gas console circuit with the purging gas;

3 increase the pressure to the maximum pressure of purging gas;

4 reduce the pressure of the gas console circuit to atmosphere pressure

Conformity shall be checked by risk analysis and the following test

Gas lines must be filled with combustible gas and tested using a gas detector after installation of all devices, including valves and fittings Following this, the gas lines should be purged according to the instruction manual Once purging is complete, the gas detector must be used again to confirm that the gas levels in the lines are below the lower flammability level (LFL) of the gas If multiple combustible gases are utilized, this testing process must be repeated for each gas.

Enclosure

Design requirements

The gas console (external or internal) shall be designed to withstand or prevent an explosion

This shall be accomplished by complying with at least one of the requirements in 9.3.2 through 9.3.4

NOTE All tests described below are dangerous, and it is recommended that they are performed by qualified personnel.

Enclosure purging

Purging involves the use of positive pressure from an inert gas and forced ventilation, such as a non-arcing fan It is essential to activate any automatic purging systems for the gas console enclosure to eliminate combustible gases before energizing other electrical devices.

Where a fan or other device is used for purging, a malfunction shall be indicated and the system shall be prevented from continuing to operate

After purging, the level of combustible gas shall not exceed the lower explosion level (LEL)

Conformity must be verified in a draught-free environment through one of two methods The first method involves simulating a continuous gas leak within the enclosure at the manufacturer's specified maximum flow rate and pressure, monitoring the gas until saturation occurs, and activating the purging devices to ensure the gas reaches the Lower Explosive Limit (LEL) before energizing any potential ignition sources This process should be repeated for each type of combustible gas The second method requires placing a simulated arcing device inside the purged enclosure, adjusting the gas until saturation is achieved, and operating all purging means before initiating the start-up sequence The arcing device is then energized to mimic electronics start-up, ensuring continuous operation without ignition, and this should also be repeated for each type of combustible gas.

NOTE 1 A safe level of gas is 50 % of the LEL

NOTE 2 The leak rate needs to be considered when performing these tests

Safe design of gas console

The gas console shall be designed to prevent an ignition caused by a gas leak in the enclosure

To ensure conformity, follow these steps: First, place the energized equipment, such as the external gas console or the internal gas console's power source, in a bag Next, simulate a gas leak to create an internal explosive atmosphere and monitor the gas mixture until it reaches a level between the Lower Explosive Limit (LEL) and the Upper Explosive Limit (UEL) Operate the gas console for at least one hour, cycling all ignition-capable components a minimum of 100 times, and confirm that no ignition occurs during this period Finally, ignite the bag to verify the presence of a flammable mixture.

The enclosure, i.e the external gas console or the power source with internal gas console, shall withstand an explosion without degradation of the protective continuity circuit

To ensure conformity, follow these steps: First, place the non-energized equipment, such as the external gas console or the power source with an internal gas console, in a bag Next, simulate a gas leak to create an internal explosive atmosphere and monitor the gas mixture until it reaches a level between the Lower Explosive Limit (LEL) and the Upper Explosive Limit (UEL) Then, ignite the flammable mixture using an arcing device within the equipment to create an explosion, ensuring there is no flying debris Additionally, check for contact with live hazardous parts using the jointed test finger as per IEC 60529 standards, and verify the continuity of the protective circuit through visual inspection and measurement.

Open structure

An open-structure gas console designed with no enclosure or a partial enclosure that cannot accumulate a combustible mixture and cause an explosion shall be considered safe

Conformity shall be checked by design review.

Solid filled enclosure

A gas console designed with an enclosure that does not contain any empty volume that can accumulate oxygen or a combustible mixture shall be considered safe

Conformity shall be checked by design review.

In areas where combustible gases are utilized, the external gas console must exclusively house the necessary electric and non-electric equipment, such as electromagnetic valves, metering devices, flow meters, and control circuits, that are essential for directing gases to the torch.

Conformity shall be checked by visual inspection.

In areas where combustible gases are utilized, it is essential to ensure that the internal gas console gas lines and components are separated by a barrier from the live components of the power source within the same enclosure Additionally, gas console control circuits can be positioned on either side of this barrier.

Conformity shall be checked by visual inspection

Gas hoses and tubing

Gas hoses and tubing must be appropriate for their intended use and should be rated to withstand the maximum pressure and temperature as specified by product ratings.

Gas hoses for supply must be clearly color-coded or marked according to Table 1 If a gas supply circuit carries multiple types of gas, marking of hoses and tubing is not required as long as the design effectively prevents any misconnections.

Table 1 – Colour coding and marking

Acetylene and other combustible gases (except LPG, MPS, natural gas, red methane) Red

Air, nitrogen, argon, CO 2 Black

LPG, MPS, natural gas, methane orange Orange

All fuel gases (included in this table) red-orange Red-orange

NOTE 1 The manufacturer should be consulted on the suitability of the hose for use with hydrogen or propylene

NOTE 2 This table is taken from ISO 3821 [8]

Conformity shall be checked by visual inspection and the test given in 10.3.

Gas fittings

Supply gas fittings shall not be interchangeable (for example, size, thread type) to avoid mixing fuel gases with inert gases or oxygen/air

Leak test

Assemblies through which gas flows shall be capable of operating under the rated inlet pressure at the rated operating temperature, without a hazardous leak as specified by the manufacturer

Conformity shall be checked by a test specified by the manufacturer to ensure a safe assembly

NOTE Air or inert gas used for this test should not contain contaminants that could degrade components used with O 2

Control circuits not connected to the welding circuit must adhere to specific requirements: the operating voltage should not exceed 250 V, and a transformer with separate windings is necessary for their supply Additionally, both overvoltage and overcurrent protection must be implemented, and any single-fault conditions that could compromise safety need to be assessed Furthermore, the transformer secondary circuits, excluding SELV, must be grounded, and the insulation of bundled conductors should be rated for the highest voltage present It is also essential that software and logic circuits do not negatively impact safety, and any control circuits exiting the enclosure must be isolated from the primary circuit using double or reinforced insulation.

NOTE 1 These requirements are based on IEC 60204-1[2]

Conformity shall be checked by measurement or analysis, as appropriate

There are two main types of control circuits in welding and cutting equipment: internal control circuits located within the equipment enclosure and external control circuits designed for interfacing between the power source and peripheral or ancillary equipment Additionally, control circuits are also utilized within the gas console for enhanced functionality.

As specified in Clause 15 of IEC 60974-1, with the following modifications (as applicable): a) type of gas(es) used; b) maximum inlet gas pressure; c) maximum gas flow rating for each gas

See Annex B for an example of a rating plate layout that may be used for an external gas console.

When specifying a gas console within a welding power source enclosure, it is essential to adhere to the welding power source rating outlined in Clause 15 of IEC 60974-1, along with additional details such as the standard reference, types of gas(es) utilized, maximum inlet gas pressure, and the maximum gas flow rating for each gas.

Each gas console shall be delivered with instructions and markings.

Instructions

According to IEC 60974-1, section 17.1, essential guidelines include the selection and connection of gas hoses and I/O cables, as well as EMC information pertinent to equipment installation and operation It is crucial to address gas purging after any changes in gas routing, ensure proper ventilation during installation, and adhere to specified gas flow rates and maximum pressures Additionally, the purity of the gas source must be considered, and flashback arrestors are mandatory to prevent fire hazards, unless exceptions apply for certain gases or pressures Recommendations for the lifespan and replacement of internal flexible hoses for combustible gases and oxygen, along with precautions against contamination of oxygen lines, are also vital Lastly, general installation and operational guidelines, such as torch positioning relative to the gas console, should be followed to ensure safety and compliance.

NOTE The torch used in arc welding, plasma cutting and gouging is an obvious source of ignition necessary for its intended function

Marking

As specified in 17.2 of IEC 60974-1, (as applicable) and with the following addition

Each gas connection shall be legibly and indelibly marked The gas connections shall be marked with the maximum pressure and the type(s) of gas(es)

Conformity shall be checked by visual inspection

Figure A.1 – Example of a mechanized plasma system

Cable-hose assembly (relevant standards)

Cable-hose assembly of the torch IEC 60974-7

Example of a rating plate layout

1 Name and address of the manufacturer or distributor or importer and optionally a trademark and the country of origin, if required

2 Reference to this standard conforming that the gas console complies with its requirements

3 Type (identification) as given by the manufacturer and traceability of design and manufacturing data, for example, serial number

4 Type of gases used (for example, H 2 or O 2 )

7 Maximum inlet gas pressure: MPa (bar)

8 Maximum gas flow rating for each gas: l/min

9 Degree of protection rating: IPXX

Figure B.1 – Principle of a rating plate

[1] IEC 60050-426:2008, International Electrotechnical Vocabulary – Part 426: Equipment for explosive atmospheres

[2] IEC 60204-1, Safety of machinery − Electrical equipment of machines – Part 1: General requirements

[3] IEC 60664-1, Insulation coordination for equipment within low-voltage systems − Part 1:

[4] IEC 60974-2, Arc welding equipment − Part 2: Liquid cooling system

[5] IEC 60974-3, Arc welding equipment − Part 3: Arc striking and stabilizing devices

[6] IEC 60974-7, Arc welding equipment − Part 7: Torches

[7] IEC 61010-1:2001, Safety requirements for electrical equipment for measurement, control, and laboratory use – Part 1: General requirements

[8] ISO 3821, Gas welding equipment − Rubber hoses for welding, cutting and allied processes

[9] ISO 12170, Gas welding equipment − Thermoplastic hoses for welding and allied processes

6 Protection contre les chocs électriques 24

6.2 Protection contre les chocs électriques en service normal (contact direct) 24

6.3 Protection contre les chocs électriques en cas de défaut (contact indirect) 24

8 Raccordements pour les torches de coupage plasma 25

9.1 Protection contre le feu ou l’explosion 25

9.2 Purge des conduites de gaz 25

9.3.3 Conception sûre de la console de gaz 27

10.1 Conduites et tuyaux de gaz 28

Annexe A (informative) Diagramme de système plasma mécanisé 32

Annexe B (informative) Exemple de disposition de plaque signalétique 33

Figure A.1 – Exemple d’un système plasma mécanisé 32

Figure B.1 – Principe de la plaque signalétique 33

Tableau 1 – Code couleur et marquage 28

Partie 8: Consoles de gaz pour soudage et systèmes de coupage plasma

The International Electrotechnical Commission (IEC) is a global standards organization that includes all national electrotechnical committees Its primary goal is to promote international cooperation on standardization issues in the fields of electricity and electronics To achieve this, the IEC engages in various activities, including the publication of standards.

The International Electrotechnical Commission (IEC) develops Technical Specifications, Technical Reports, Publicly Available Specifications (PAS), and Guides, collectively referred to as "IEC Publications." The creation of these documents involves study committees, which allow participation from any national committee interested in the subject matter Additionally, international, governmental, and non-governmental organizations collaborate with the IEC in this process The IEC works closely with the International Organization for Standardization (ISO) under terms established by an agreement between the two organizations.

Official decisions or agreements of the CIS regarding technical issues aim to establish an international consensus on the topics under consideration, as each study committee includes representatives from the relevant national committees.

IEC publications are issued as international recommendations and are approved by the national committees of the IEC The IEC makes every reasonable effort to ensure the technical accuracy of its publications; however, it cannot be held responsible for any misuse or misinterpretation by end users.

To promote international unification, the national committees of the CIS commit to transparently implementing CIS international standards into their national and regional regulations Any discrepancies between CIS standards and corresponding national or regional standards must be clearly stated.

5) La CEI n’a fixé aucune procédure concernant le marquage comme indication d’approbation et sa responsabilité n’est pas engagée quand un matériel est déclaré conforme à l’une de ses normes

6) Tous les utilisateurs doivent s'assurer qu'ils sont en possession de la dernière édition de cette publication

The IEC and its administrators, employees, agents, including external experts and members of its study committees and national committees, shall not be held liable for any injuries, damages, or any other type of loss, whether direct or indirect This includes any costs or expenses, such as legal fees, arising from the publication or use of this IEC Publication or any other IEC Publication, or from the credit attributed to it.

8) L'attention est attirée sur les références Normatives citées dans cette publication L'utilisation de publications référencées est obligatoire pour une application correcte de la présente publication

Attention is drawn to the fact that some elements of this IEC publication may be subject to intellectual property rights or similar rights The IEC cannot be held responsible for failing to identify such property rights or for not indicating their existence.

La Norme Internationale CEI 60974-8 a été établie par le comité d'études 26 de la CEI:

La présente norme doit être utilisée conjointement avec la CEI 60974-1

Cette deuxième édition annule et remplace la première édition parue en 2004 et constitue une révision technique

Les modifications significatives par rapport à l'édition antérieure sont les suivantes:

• retrait de la conception de sécurité intrinsèque;

• introduction de la fonction mélange du gaz;

• nouvelle disposition informative de la plaque signalétique;

• modifications induites par la publication de l’édition 3 de la CEI 60974-1

The English text of this standard is derived from documents 26/381/CDV and 26/391/RVC The voting report 26/391/RVC provides all the information regarding the vote that led to the approval of this standard.

La version franỗaise de cette norme n’a pas ộtộ soumise au vote

Cette publication a été rédigée selon les Directives ISO/CEI, Partie 2

The committee has determined that the content of this publication will remain unchanged until the maintenance date specified on the IEC website at http://webstore.iec.ch On that date, the publication will be updated.

• remplacée par une édition révisée, ou

Partie 8: Consoles de gaz pour soudage et systèmes de coupage plasma

This section of IEC 60974 outlines the performance and safety requirements for gas consoles intended for use with combustible gases or oxygen These gas consoles are designed to supply gas for arc welding, plasma cutting, gouging, and related processes in non-explosive environments.

The gas console can be located either outside or inside the power source enclosure In the latter case, the current standard also applies to the power source.

NOTE Voir l’Annexe A pour le schéma du système de plasma mécanisé

The following reference documents are essential for the application of this document For dated references, only the cited edition is applicable For undated references, the latest edition of the reference document applies, including any amendments.

CEI 60050-151, Vocabulaire Electrotechnique International – Partie 151: Dispositifs électriques et magnétiques

CEI 60529, Degrés de protection procurés par les enveloppes (Code IP)

CEI 60974-1:2005, Matériel de soudage à l’arc – Partie 1: Sources de courant de soudage

Pour les besoins de la présente norme, les termes et définitions suivants, ainsi que ceux des

3.1 console de gaz dispositif destiné à acheminer, à mélanger le gaz ou les deux, qui contient des appareils électriques dans une seule ou plusieurs enceintes, ou en structure ouverte

LIE concentration dans l’air d’un gaz ou d’une vapeur inflammable en dessous de laquelle l’atmosphère gazeuse n’est pas explosive

1 Les chiffres entre crochets renvoient à la bibliographie

LII concentration minimale de gaz combustible dans un mélange dont une combustion peut être obtenue en utilisant une source d’inflammation

LSE concentration dans l’air d’un gaz ou d’une vapeur inflammable au dessus de laquelle l’atmosphère gazeuse n’est pas explosive

LSI concentration maximale de gaz combustible dans un mélange dont une combustion peut être obtenue en utilisant une source d’inflammation

3.6 console de gaz externe console de gaz qui n’est pas incorporée dans une source de courant

3.7 console de gaz interne console de gaz qui est incorporée dans une source de courant

3.8 condition de premier défaut condition dans laquelle un moyen de protection contre les dangers est défectueux

NOTE Lorsqu’une condition de premier défaut résulte irrémédiablement d’une autre condition de premier défaut, les deux défaillances sont considérées comme une condition de premier défaut

[définition 3.5.11 de la CEI 61010-1 modifiée] [7]

Comme spécifié à l’Article 4 de la CEI 60974-1

Conditions d'essais

Comme spécifié au 5.1 de la CEI 60974-1.

Appareils de mesure

Conformité des composants

Essais de type

Comme spécifié au 5.4 de la CEI 60974-1

Les autres essais inclus dans la présente norme peuvent être effectués dans n’importe quel ordre approprié.

Essais individuels de série

Console de gaz externe

All individual series tests must be conducted on each external gas console in the following order: a) general visual inspection as per section 3.7 of IEC 60974-1; b) continuity of the protection circuit according to section 10.4.2 of IEC 60974-1; c) dielectric strength testing as outlined in section 6.1.5 of IEC 60974-1; d) leak testing as specified in section 10.3; e) final general visual inspection in accordance with section 3.7 of IEC 60974-1.

Console de gaz interne

Tous les essais individuels de série doivent être effectués sur chaque console de gaz interne comme spécifié au 5.5 de la CEI 60974-1, avec l’ajout suivant: g) essai d’étanchéité, voir 10.3

6 Protection contre les chocs électriques

Isolation

Comme spécifié au 6.1 de la CEI 60974-1, à l’exception de ce qui suit:

Les cartes à circuits imprimés doivent être sous enveloppe, recouvertes ou enrobées.

Protection contre les chocs électriques en service normal (contact direct)

Protection procurée par l’enveloppe

Le degré minimal de protection des consoles de gaz doit être IP21S selon la CEI 60529

Compliance must be verified by a) using a finger probe and ball, as specified in IEC 60529, at each opening to ensure that no hazardous parts are touched; and b) confirming that immediately after the water test, as outlined in IEC 60529, the unit meets insulation resistance and dielectric strength tests and is capable of functioning.

Aucune alimentation n’est fournie à l’unité pendant la réalisation de ces essais.

Condensateurs

Comme spécifié au 6.2.2 de la CEI 60974-1.

Protection contre les chocs électriques en cas de défaut (contact indirect)

Essai d’échauffement

Pour une console de gaz externe, seuls les essais applicables sont réalisés.

Température maximale

La température ne doit pas dépasser en tout point la température d’inflammabilité de tout gaz combustible destiné à être utilisé dans la console de gaz

Compliance must be verified by operating the gas console according to the manufacturer's specifications, including a) the gas combinations and flow rates that create the worst-case scenario as specified by the manufacturer, and b) the coolant as specified by the manufacturer.

8 Raccordements pour les torches de coupage plasma

Comme spécifié au 11.4.6 de la CEI 60974-1, ó la torche est raccordée à la console de gaz

Comme spécifié à l’Article 14 de la CEI 60974-1, avec les ajouts suivants:

Protection contre le feu ou l’explosion

The gas console must be designed to protect against fire or explosion under normal operating conditions or in the event of a primary failure, such as defective valves or pipes.

When a gas console operates with a combustible gas, every circuit, subsystem, or component must not generate temperatures or sparks with enough energy to trigger ignition.

Lorsqu’une console de gaz utilise un gaz combustible appartenant à un mélange, celui-ci ne doit pas être inclus sans limite d’inflammabilité définit par LII et LSI

Compliance must be ensured through a) the evaluation of the design and calculations of circuits, subassemblies, or the verification of components; or b) the application of a fault (such as an open circuit, short circuit, and/or movement restriction) to circuits, subassemblies, or components until an event occurs (for example, a spark that does not cause ignition, a fuse that opens, a unit that stops, etc.) or a permanent temperature is reached.

Purge des conduites de gaz

The gas console must have a mechanism to purge gas lines when switching to a different type of gas, such as from a non-combustible gas or one containing oxygen to a combustible gas, in order to minimize the risk of fire or explosion In certain situations, this is crucial for safety.

A small amount of combustible gas or oxygen may accumulate in the torch, and this volume should be minimized to avoid any potential risks.

La purge doit avoir lieu après chaque changement d’acheminement de gaz ou lorsque l’ancien acheminement de gaz est inconnu

NOTE 1 Un moyen pour accomplir cela peut être en purgeant les conduites avec un volume de gaz inerte suffisant

NOTE 2 Lorsqu’un risque d’incendie ou d’explosion subsiste dans les conduites de gaz à cause du changement de gaz, la purge peut être effectuée avec le cycle de pression suivant:

1 réduire la pression du circuit de la console de gaz jusqu’à la pression atmosphérique;

2 purger du circuit de la console de gaz à l’aide du gaz destiné à la purge;

3 augmenter la pression jusqu’à la pression maximale du gaz destiné à la purge;

4 réduire la pression du circuit de la console de gaz jusqu’à la pression atmosphérique

La conformité doit être contrôlée par une analyse de risque et l’essai suivant

Les conduites de gaz, une fois munies de tous les dispositifs (robinets, raccords, etc.) doivent être remplies avec un gaz combustible et mesurées à l’aide d’un détecteur de gaz

Immediately after, gas lines must be purged according to the instruction manual Following the purge, the gas content in the lines should be measured with a gas detector to ensure that the levels are below the lower explosive limit (LEL) of the specific gas If multiple combustible gases are used, the testing must be repeated for each gas.

Enveloppe

Exigences de conception

The gas console, whether external or internal, must be designed to withstand or prevent an explosion This should be achieved by adhering to at least one of the requirements specified in sections 9.3.2 to 9.3.4.

NOTE Tous les essais décrits ci-après sont dangereux et il est recommandé qu’ils soient réalisés par du personnel qualifié.

Purge de l’enveloppe

Purge methods typically involve the use of positive pressure from inert gas and forced ventilation, which utilizes a fan that does not ignite an arc Any automatic means for purging the console housing of combustible gases must be activated before powering on any other electrical devices.

Lorsqu’un ventilateur ou autre dispositif est utilisé pour la purge, toute défaillance doit être indiquée et le système doit être empêché de continuer à fonctionner

Après la purge, le niveau de gaz combustible ne doit pas dépasser la limite inférieure d’explosivité (LIE)

Compliance must be monitored in a draft-free environment by either simulating a continuous gas leak within the envelope at the maximum flow rate and pressure specified by the manufacturer or by following the outlined procedures It is essential to monitor and adjust the gas within the envelope until saturation or stabilization occurs Additionally, activate the purge devices and ensure that the gas reaches the Lower Explosive Limit (LEL) before any potential ignition source is energized This process should be repeated for each type of combustible gas used.

Licensed to MECON Limited for internal use at this location only, supplied by Book Supply Bureau Place a simulated ignition device inside the purged envelope Monitor and adjust the gas within the envelope until saturation or stabilization is achieved Operate all purging means and initiate a startup sequence Power the ignition device to simulate the operation of electronic components, ensuring continuous operation without any ignition Repeat this process for each type of combustible gas used.

NOTE 1 Un niveau de gaz sûr correspond à 50 % de la LIE

NOTE 2 Lors de la réalisation de ces essais, il est nécessaire de prendre en considération le débit de fuite.

Conception sûre de la console de gaz

La console de gaz doit ờtre conỗue pour empờcher une inflammation due à une fuite de gaz dans l’enveloppe

To ensure compliance, the following test must be conducted: a) Power on the equipment, including the external gas console or power supply and the internal gas console, placing it in a bag or similar containment b) Simulate a gas leak within the equipment to create an explosive internal atmosphere c) Monitor the gas mixture until it reaches a level between the Lower Explosive Limit (LEL) and the Upper Explosive Limit (UEL) d) Operate the gas console for at least one hour, cycling all components that could cause ignition a minimum of 100 times during this period e) Confirm that no ignition occurs throughout the operation f) Ignite the bag or similar containment to verify the presence of a flammable mixture.

The envelope, which refers to the external gas console or power supply and the internal gas console, must withstand an explosion without compromising the continuity protection circuit.

Compliance must be verified through the following test: a) Place the unpowered equipment, such as the external gas console or power supply and the internal gas console, in a bag or similar container b) Simulate a gas leak inside the equipment to create an explosive internal atmosphere c) Monitor the mixture until it reaches halfway between the Lower Explosive Limit (LEL) and the Upper Explosive Limit (UEL) of the gas d) Ignite the flammable mixture using an ignition device incorporated into the equipment to create an explosion e) Ensure there are no fragments f) Check for any contact with hazardous live parts using the specified articulated test finger according to IEC 60529 g) Verify the continuity of the protection circuit through visual inspection and measurement.

Structure ouverte

An open-structure gas console, designed without a full casing or with a partial casing that cannot accumulate a combustible mixture, is deemed safe as it minimizes the risk of explosion.

La conformité doit être contrôlée par examen de la conception.

Enveloppe pleine

Une console de gaz conỗue avec une enveloppe qui ne contient aucun volume vide qui puisse accumuler de l’oxygène ou un mélange combustible doit être considérée sûre

La conformité doit être contrôlée par examen de la conception.

La console de gaz externe ne doit renfermer que les appareils électriques et non électriques

(par exemple électrovannes, appareils de mesure, débitmètres, circuits de commande) requis pour acheminer les gaz combustibles vers la torche

La conformité doit être contrôlée par examen visuel.

When using combustible gases, the gas lines and components of the internal gas console must be separated by a barrier from the active parts of the power source located within the same enclosure The control circuits of the gas console can be positioned on either side of this barrier.

La conformité doit être contrôlée par examen visuel

Conduites et tuyaux de gaz

Gas pipes and conduits must be suitable for their specific applications They should be rated for the maximum pressure and temperature in accordance with the product's nominal specifications.

Gas supply pipes must be properly identified using a color code as specified in Table 1 If the gas supply circuit delivers more than one type of gas, the pipes do not need to be marked, provided that the design prevents connection errors.

Tableau 1 – Code couleur et marquage

Acétylène et autres gaz combustibles (sauf GPL, MPS, gaz naturel, méthane rouge) Rouge

Air, azote, argon, CO 2 Noir

GPL, MPS, gaz naturel, orange méthane Orange

Tous les gaz combustibles (inclus dans ce tableau) rouge-orange Rouge-orange

NOTE 1 Il convient que le fabricant soit consulté sur la pertinence d’utiliser le tuyau pour de l’hydrogène ou du propylène

NOTE 2 Ce tableau est issu de l’ISO 3821 [8]

La conformité doit être contrôlée par examen visuel et en effectuant l’essai indiqué au 10.3.

Raccords de gaz

Gas supply fittings must not be interchangeable, such as in size or thread type, to prevent the mixing of combustible gases with inert gases or oxygen/air.

Essai d’étanchéité

Gas systems must operate at the specified nominal inlet pressure and service temperature without any hazardous leaks, as outlined by the manufacturer.

La conformité doit être contrôlée en effectuant un essai spécifié par le fabricant pour garantir un assemblage sûr

NOTE Il convient que l’air ou le gaz inerte utilisé pour cet essai ne contienne pas de contaminants pouvant dégrader les composants utilisés avec O 2

Control circuits that are not connected to the welding circuit must meet specific requirements Firstly, the operating voltage of these control circuits should not exceed 250 V Additionally, a transformer with separate windings must be used to power the control circuits It is also essential to provide surge protection and overcurrent protection Furthermore, any first fault conditions that could impact safety must be assessed Lastly, the secondary circuits of the transformers should be grounded, with certain exceptions.

The insulation of conductor bundles must be rated for the highest voltage of any individual conductor Software and logic circuits should not compromise safety Additionally, control circuits that are separated from the enclosure must be isolated from the primary circuit using double or reinforced insulation.

NOTE 1 Ces exigences sont basées sur la CEI 60204-1[2]

La conformité doit être contrôlée par des mesures ou des analyses, selon ce qui est approprié

There are two types of control circuits: a) internal control circuits within the welding/cutting equipment's housing; b) control circuits designed to serve as an interface between the power source and the peripheral equipment created by the manufacturer.

Licensed to MECON Limited for internal use in Ranchi and Bangalore, supplied by Book Supply Bureau This includes control circuits designed to interface between the power source and various auxiliary equipment, as well as control circuits intended for installation within the gas console.

Comme spécifié à l’Article 15 de la CEI 60974-1, avec les modifications suivantes (le cas échéant): a) type(s) de gaz utilisé(s); b) pression maximale d’entrée de gaz; c) débit de gaz maximal pour chaque gaz

Voir l’Annexe B pour un exemple de disposition de plaque signalétique qui peut être utilisé pour une console de gaz externe.

For a gas console included in a welding power source enclosure, the specifications outlined in Article 15 of IEC 60974-1 must be followed, with the following additions: a) normal reference; b) type(s) of gas used; c) maximum gas inlet pressure; d) maximum gas flow rate for each gas.

Chaque console de gaz doit être fournie avec des instructions et des marquages

According to section 17.1 of IEC 60974-1, the following information is essential: a) guidance on selecting and connecting gas pipes and I/O cables; b) electromagnetic compatibility (EMC) details specific to the installation and operation of the equipment; c) gas purging procedures, particularly after any changes in gas routing; d) ventilation requirements for installation; e) maximum gas flow rates and pressures; f) information regarding the gas source, including purity; g) a statement indicating the necessity of backfire flame arrestors, unless unavailable for specific gases or required pressures, to prevent fire from propagating back to the gas supply; h) recommended lifespan and replacement guidelines for internal flexible hoses for combustible gas and oxygen; i) information on the contamination of oxygen lines.

This document is licensed to MECON Limited for internal use at the Ranchi and Bangalore locations, as supplied by the Book Supply Bureau It includes specific general information regarding the installation and operation of the specified equipment, such as the torch's location in relation to the gas console and its power supply.

NOTE La torche utilisée pour le soudage à l’arc, le coupage plasma et le gougeage est évidemment une source d'inflammation, nécessaire pour la fonction prévue

Marquage

Comme spécifié au 17.2 de la CEI 60974-1, (le cas échéant) et avec l’ajout suivant

Chaque raccord de gaz doit être marqué de manière lisible et indélébile Les raccords de gaz doivent porter l’inscription concernant la pression maximale et le(s) type(s) de gaz

La conformité doit être contrôlée par examen visuel

Diagramme de système plasma mécanisé

Figure A.1 – Exemple d’un système plasma mécanisé

Système de refroidissement par liquide CEI 60974-2

Faisceau de la torche CEI 60974-7

Ensemble de soupape torche CEI 60974-1

Exemple de disposition de plaque signalétique

1 Nom et adresse du fabricant ou du distributeur ou de l’importateur et, éventuellement, une marque commerciale et le pays d’origine, si nécessaire

2 Référence à la présente norme stipulant que la console de gaz est conforme à ses exigences

3 Type (identification) donnộ par le fabricant et la traỗabilitộ des donnộes de conception et de fabrication, par exemple le numéro de série

4 Type de gaz utilisés (par exemple, H2 ou O2)

7 Pression maximale d’entrée de gaz: MPa (bar)

8 Débit de gaz maximal pour chaque gaz: l/min

9 Degré de l’indice de protection: IPXX

Figure B.1 – Principe de la plaque signalétique

[1] CEI 60050-426:2008, Vocabulaire Electrotechnique International – Partie 426: Matériel pour atmosphères explosives

[2] CEI 60204-1, Sécurité des machines − Equipement électrique des machines – Partie 1:

[3] CEI 60664-1, Coordination de l’isolement des matériels dans les systèmes (réseaux) à basse tension – Partie 1: Principes, exigences et essais

[4] CEI 60974-2, Matériel de soudage à l’arc – Partie 2: Systèmes de refroidissement par liquide

[5] CEI 60974-3, Matộriel de soudage à l’arc – Partie 3: Dispositifs d’amorỗage et de stabilisation de l’arc

[6] CEI 60974-7, Matériel de soudage à l’arc – Partie 7: Torches

[7] CEI 61010-1:2001, Règles de sécurité pour appareils électriques de mesurage, de régulation et de laboratoire – Partie 1: Prescriptions générales

[8] ISO 3821, Matériel de soudage aux gaz − Tuyaux souples en caoutchouc pour le soudage, le coupage et les techniques connexes

[9] ISO 12170, Matériel de soudage aux gaz − Tuyaux souples en matière thermoplastique pour le soudage et les techniques connexes

Tiêu đề	Arc welding equipment – Part 8: Gas consoles for welding and plasma cutting systems
Chuyên ngành	Electrical Engineering
Thể loại	Standard
Năm xuất bản	2009

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Số trang	38
Dung lượng	0,99 MB