[Basic concepts for explosion protection] - Scame · [Basic concepts for explosion protection] 1...

[Basic concepts for explosion protection]

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General Index

1. Introduction Pag. 2

2. Group and equipment category Pag. 3

3. North American Standards Pag. 5

4. Conformity Pag. 6

5. Comparison of IEC Publication and European Standards (EN) Pag. 7

6. Types of protection Pag. 8

7. Protection concept Pag. 17

8. Apparatus groups & temperature classes for common flammable materials Pag. 18

9. Temperature Class (group II) Pag. 18

10. Marking Pag. 19

11. SCAME products range Pag. 22

‐ ZENITH P Series Increased Safety Enclosures and Terminal Boxes for Applications in Hazardous Environments Pag. 23

‐ ALUBOX-Ex Series

Junction boxes in aluminium alloy Pag. 31

‐ ADVANCE GRP Series

Interlocked switch sockets outlets Pag. 32

‐ OPTIMA-Ex Series

Industrial plugs Pag. 33

‐ ISOLATORS Series Switch-disconnectors

Pag.

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1. Introduction Products for use in explosive atmospheres – ATEX Here is a simple guide to ATEX, its meaning and how to choose the right products for your application.

What is ATEX? ATEX is a European Directive (94/9/EC) valid for products to be used within an explosive atmosphere. The ATEX directive has been in force throughout the European Union since 1 July 2003, replacing the existing different national and European legislation relating to explosive atmospheres. ATEX = “ATmosphere EXplosive” Why ATEX? An ambience with the potential to become an explosive atmosphere during operating conditions and/or under the influence of the environment is defined as a potentially explosive atmosphere. Products covered by directive 94/9/EC are defined as intended for use in potentially explosive atmospheres. Directive 94/9/EC defines an explosive atmosphere as a mixture of:

a) flammable substances gases, vapors, mists or dusts b) with air c) under specific atmospheric conditions d) in which, after ignition has occurred, combustion spreads to the flammable mixture

Harmonised European ATEX standard The European Union has adopted two harmonized directives in the field of health and safety. The directives are known as ATEX 100a and ATEX 137. Directive ATEX 100a (94/9/EC) lays down minimum safety requirements for products intended for use in potentially explosive atmospheres in European Union member states. Directive ATEX 137 (99/92/EC) defines minimum requirements for health and safety at the workplace, for working conditions and for the handling of products and materials in potentially explosive atmospheres. This directive divides the workplace into zones and defines criteria by which products are categorized within these zones.

ATEX

ATEX 94/9/EC (ATEX 100a)

Products directive Covers manufacturers health and safety

requirements

ATEX 100a Product directive

Products requirements

ATEX 199/92/EC (ATEX 137)

Workers directive Covers and users minimum requirements for

health and safety protection of workers

ATEX 137 Workers directive

Risks analysis

Product test Quality audit Certificates documentation instructions

Zones identification Assessment

Explosion protection document


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‐ Gives the minimum requirements in the field of safety and health protection of workers potentially at risk of explosive atmospheres.

‐ Define obligations of the employer ‐ Defines Zones and criteria for selection of equipment and protective systems

‐ Applied to equipment and protective systems intended for use in potentially explosive atmospheres. ‐ Covers all risk of explosion (not only those from electrical origin) ‐ Covers both application for mines and for other application ‐ Applied to equipment, components, safety devices, controlling devices and regulating devices .

2. Group and equipment category

Group I Mines and surface installations of such mines

Group II Other places

Category M1 very high level of protection

Category M2 high level of protection

Category 1 very high level of protection

Category 2 high level of protection

Category 3 normal level of protection

DIRECTIVE 1999/92/EC OF THE EUROPEAN PARLIAMENT

AND OF THE COUNCIL

dated 16 December 1999

on minimum requirements to improve the safety and health protection of workers potentially at risk of explosive atmospheres (15th individual Directive within the meaning

of Article 16(1) of Directive 89/391/EEC)

DIRECTIVE 94/9/EC OH THE EUROPEAN PARLIAMENT

AND THE COUNCIL

dated 23 March 1994

on the approximation of the laws of the Member States concerning equipment and protective systems intended for use in potentially explosive atmospheres

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Group II - Zones

GAS DUST Frequency and duration of the occurrence of an explosive atmosphere

0 20 continuously present or for long periods or frequently

1 21 occasionally

2 22 not likely to occur

Potentially explosive atmospheres

Group II – Categories - Zones

Category GAS DUST Frequency and duration of the

occurrence of an explosive atmosphere

Level of protection

1 0 20 Continuously present or for long periods or frequently.

‐ very high ‐ 2 means of prot. ‐ 2 faults

2 1 21 occasionally ‐ high ‐ 1 mean of prot. ‐ 1 fault

3 2 22 not likely to occur ‐ normal ‐ guaranted in normal operation

Conformity assessment procedures

Category Type of products Procedure

1 M1 All

CE type-examination (Annex III) Production quality assurance (Annex IV) or product verification

(Annex V)

2 M2

Electric CE type-examination (Annex III) Conformity to type referred (Annex VI) or Product quality assurance (Annex VII)

2 M2 Not-electric

Internal control of production (Annex VIII) and communicate the dossier to a notified body

3 All Internal control of production (Annex VIII)

For an explosive atmosphere to form, the flammable material must be present in a certain concentration. If the concentration is too low (lean mixture) or too high (rich mixture), no explosion occurs, rather there is just a slow combustion reaction or none at all. It is only in the range between the lower and upper explosion limit that the mixture reacts explosively when ignited. The explosion limits depend on the ambient pressure and the proportion of oxygen in the air.


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3. North American Standards In North America all electrical installations are governed by the National Electric Code (NEC). Electrical equipment used in ordinary, wet and hazardous (or classified) locations must be ‘listed’ by an accredited approval agency for use in the intended location. The hazardous locations include areas in which flammable, combustible or ignitable substances may occur in hazardous quantities. Article 501 Codes of the NEC use a different way of categorizing the hazardous locations, which is by Class and Division, compared with the European and IEC standards, which have adopted the Zonal method. Electrical apparatus approved in North America for use in hazardous locations must be categorized with an Equipment Class and suitable for a specified Division and Gas Group. Classifications are made in line with the type of combustible material as follows;

‐ Class I – Flammable gases, vapors or mists ‐ Class II – Combustible dusts ‐ Class III – Ignitable fibers and flying

In 1996 article 505 was introduced to the NEC which allowed Zonal classification of hazardous areas. This now means that products can be approved as follows: Either, or Class, Division & Gas Group

For example: Class 1, Division 2, A,B,C,D

Class, Zone & Gas Group For example: Class 1, Zone 2, IIA, IIB, IIC.

Although this code change permits the use of products that have a Zonal classification, in a similar way to European practice, the mixing of different forms of equipment approval across zones or divisions is not acceptable. For example products approved for Zone 1 do not necessarily meet the requirements of Division 1, which also encompasses Zone 0. Although no direct equivalents exist between European/IEC and American codes of protection and Area Classification there are similarities and there is a developing acceptance of European/IEC methods in North America and vice versa. The following table shows the basic relationships between the North American and European Classifications.

Equivalent Division/Zone

NEC European/IEC

Division 1 Zone 0 Zone 1

Division 2 Zone 2

As can be seen from the above table, Division 1 covers both the European / IEC Zones 0 & 1. Therefore, care must be taken when using zone classified equipment in a Division 1 area to ensure the suitability of the protection employed. Underwriters Laboratory (UL) and Factory Mutual (FM) are the two main certification bodies in North America and in some cases electrical equipment may also need to meet certain Marine Standards and be separately approved by the US Coast Guards, before it can be used e.g. on an offshore oil rig.

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4. - Conformity The following route to CE conformity for electrical apparatus is prescribed according to Directive 94/9/EC. Depending on the conformity category, it defines which path the manufacturer has to follow towards making the CE declaration of conformity. The overview below shows these paths for the different conformity categories.

Conformity-Assessment-Procedure Stages to be followed on the way to CE conformity and the CE mark

(*) and their components if subject to a separate certification. (•) ID number of the notified body, which certified the QA system or inspected the products.

Equipment of group I & II, category M2 & 2 (*)

Equipment of group I & II, category M1 & 1 (*) and autonomous protective

systems

Equipment of group

II, category 3 (*)

Motor with internal combustion engine, electrical equipment

QA production

Product inspection

EC declaration of conformity


EC type examination certificate

EC type examination certificate

Conformity with design

QA product

EC declaration of

conformity

EC declaration of

conformity

CE mark with ID number (•)


Internal production

control

Forwarding technical documentation

to notified bodies


CE mark without

ID number (•)

Internal production control


CE mark without ID number (•)



OR

AND YES NO

OR

AND AND


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5. Comparison of IEC Publication and European Standards (EN) Electrical Apparatus for Explosive Gas Atmospheres

IEC publications EN

IEC 60079-0 EN 50 014 General requirements

IEC 60079-1 EN 50 018 Construction and verification test of flameproof enclosures of electrical apparatus

IEC 60079-1A - Method of test for ascertainment of maximum experimental safe gap

IEC/TR 60079-2 EN 50 016 Electrical apparatus, type of protection “p”

IEC 60079-3 EN 50 020 Spark-test apparatus for intrinsically-safe circuits

IEC 60079-4 - Method of test for ignition temperature

IEC 60079-4A

IEC 60079-5 EN 50 017 Powder filling “q”

IEC 60079-6 EN 50 015 Oil-immersion “o”

IEC 60079-7 EN 50 019 Increased safety “e”

IEC 60079-10 EN 60079-10 Classification of hazardous areas

IEC 60079-11 EN 50 020 Intrinsic safety “i”

IEC 60079-12 EN 50 014 Classification of mixtures of gases or vapours with air according to their maximum experimental safe gaps and minimum ignition currents

IEC/TR 60079-13 - Construction and use of rooms or buildings protected by pressurization

IEC 60079-14 EN 60079-14 Electrical installations in hazardous areas (other than mines)

IEC 60079-15 pr EN 50 021 Electrical apparatus with type of protection “n”

IEC/TR 60079-16 - Artificial ventilation for the protection of analyser(s) houses

IEC 60079-17 EN 60079-17 Inspection and maintenance of electrical installations in hazardous areas (other than mines)

IEC 60079-18 EN 50 028 Encapsulation “m”

IEC 60079-19 pr EN 60079-19 Repair and overhaul for apparatus used in potentially explosive atmospheres (other than mines or explosives)

IEC/TR 60079-20 - Data for flammable gases and vapours, relating to the use of electrical apparatus

Electrical Apparatus for Use in the Presence of Combustible Dust

IEC publications EN

IEC 61241-1-1 Part 1: Electrical apparatus protected by enclosures Section 1: Specification for apparatus

IEC 61241-1-2 Part 1: Electrical apparatus protected by enclosures Section 2: Selection, installation and maintenance

IEC 61241-2-1 Part 2: Test methods Section 1: Methods for determining the minimum ignition temperatures of dust

IEC 61241-2-2 EN 61241-2-2 Part 2: Test methods Section 2: Methods for determining the electrical resistivity of dust in layers

IEC 61241-2-3 Part 2: Test methods Section 3: Methods for determining minimum ignition energy of dust/air mixtures

IEC 61241-3 Part 3: Classification of areas where combustible dust are or may be present

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6. Types of protection

Flameproof enclosure

Marking "Ex d" II 2 G in accordance with IEC 60079-0

Principle A type of protection in which the parts which could ignite an explosive atmosphere are located inside an enclosure which can withstand the pressure of an explosion of the explosive mixture inside, and prevents the transmission of the explosion to the explosive atmosphere surrounding the enclosure. Technically unavoidable gaps are so long and narrow that hot gases jetting out will have lost their power to cause ignition by the time they reach the outside of the enclosure, or, alternatively, if the gaps are only required for the manufacturing process they might be sealed with adhesive.

Important design parameters ‐ Mechanical strength in accordance with a defined safety factor to withstand internal explosion

pressure. ‐ As an orientation value, it may be assumed that inside the sphere approx. 0.8 MPa (8 bar) can be

generated and that this sphere used as an EEx d enclosure must be able to withstand a pressure of 1.2 MPa (12 bar).

‐ Any gap between two parts of the enclosure must be kept so narrow and long that hot gas flowing out will not be able to ignite any explosive atmosphere which may be present in the potentially explosive atmosphere.

‐ The parameters for the gaps preventing the transmission of the ignition, width/length, are different for the explosion subgroups IIA, IIB and IIC. The most stringent requirements with regard to the gap parameters apply to enclosures in explosion subgroup IIC.

Applications ‐ Equipment where, during normal operation, sparks, electric arcs and/or hot surfaces are generated

such as switchgear, slip rings, collectors, adjustable resistors, fuses or lamps, heating cartridges, friction brakes.

Protection by enclosure

Marking "Ex tD" II 2 D in accordance with IEC 61241-0

Principle The enclosure is sealed so tight, that no combustible dust can enter. The surface temperature of the external enclosure is limited.

Important design parameters ‐ Minimum degree of protection in accordance with IEC/EN 60529 IP 6X. ‐ Consideration of dust accumulating on the surface and reduction of permissible surface temperature

with dust layer ≥ 5 mm are possible.

Applications ‐ Various equipment where during normal operation sparks, electric arcs or hot surfaces occur and

complex industrial designs (controllers) which by means of this type of protection can be utilized in the potentially explosive atmosphere.


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Enclosed break device

Marking "Ex nC" II 3 G in accordance with IEC 60079-0

Principle Switchgear as a variant of the Ex n type of protection, with contacts which close and open a circuit potentially able to trigger an explosion, where the enclosure will withstand an internal explosion of a mixture of subgroup IIA, IIB or IIC without being damaged and without transferring the explosion to the external mixture in the surrounding area.

Important design parameters ‐ Free internal volume ≤20 cm³. ‐ The encapsulation must permit a permanent temperature of ≥10 K compared to the maximum

operating temperature ‐ Limited to AC 690 V and 16 A.

Applications ‐ Contact systems

Non-incendive component


Principle Variant of the Ex n type of protection with contacts which close and open a circuit potentially able to trigger an explosion, where the contact mechanism or the enclosure into which the contacts are enclosed is designed in such a way that the ignition of a mixture of subgroup IIA, IIB or IIC in the surrounding environment is prevented as long as defined operating conditions apply.

Important design parameters ‐ Free internal volume ≤20 cm³. ‐ The encapsulation must permit a permanent temperature of ≥10 K compared to the maximum

operating temperature. ‐ The combination of the parts is tightly sealed or ‐ The design of the contacts will extinguish any incipient flame. ‐ Limited to AC 254 V and 16 A. ‐ L and C are part of the test. ‐ Explosion subgroups IIA, IIB and IIC are to be treated differently.

Applications ‐ Contact systems

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Pressurized apparatus

Marking "Ex p" II 2 G in accordance with IEC 60079-0 Marking "Ex pD" II 2 D in accordance with IEC 61241-0

Principle The ingress of the surrounding atmosphere into the enclosure of electrical equipment is prevented by maintaining an ignition shield gas (air, inert or a different suitable gas) inside it at a pressure above atmospheric pressure. The overpressure is maintained with or without constant flushing of the protective gas.

Important design parameters ‐ Strength of the enclosure; the surrounding, flushed enclosure must withstand 1.5 times the

overpressure experienced during normal operation. ‐ Flush before commissioning the electrical equipment. ‐ Shut-down or alarm if the flushing gas flow or overpressure fails.

Applications ‐ Equipment where during normal operation sparks, electric arcs or hot surfaces are generated and

complex industrial equipment (controls) which must be operated in a potentially explosive atmosphere protected by this type of protection.

‐ Large machines, slip ring or collector motors, switch cabinets and control cabinets and analytical apparatus.

n-pressurization

Marking "Ex pz" II 3 G in accordance with IEC 60079-0

Principle Use of a protective gas preventing ignition inside an enclosure to prevent the formation of an explosive atmosphere inside the enclosure by maintaining a pressure greater than the that in the surrounding atmosphere.

Important design parameters ‐ The important difference from the pressurized enclosure is the restriction to an enclosure where no

internal sources are available and no flammable gases or vapors can be released. ‐ Strength of the enclosure. ‐ Flush before commissioning the electrical equipment. ‐ Shut-down or alarm if the flushing gas flow or overpressure fails.

Applications ‐ Equipment where during normal operation sparks, electric arcs or hot surfaces are generated and

complex industrial equipment (controls) which must be operated in a potentially explosive atmosphere protected by this type of protection.

‐ Analytical apparatus without internal sources.


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Powder filling

Marking "Ex q" II 2 G in accordance with IEC 60079-0

Principle By filling the enclosure with a finely grained powder, an arc within the enclosure is unable, with correct use, to ignite the explosive atmosphere outside. There must be no risk of ignition by flames, nor by increased temperatures at the surface of the enclosure.

Important design parameters ‐ The filling such as sand, glass balls etc. has to fulfill specific requirements, as must the design of the

enclosure. The filling must not be able to leave the enclosure, neither during normal operation, nor as the result of electric arcs or other processes inside the powder-filled enclosure.

Applications ‐ Capacitors, electronic assembly groups or transformers which are used in a potentially explosive

atmosphere. Often components where sparks or hot surfaces occur but whose functioning is not affected by the finely grained filling.

Oil immersion

1) Marking "Ex o" II 2 G in accordance with IEC 60079-0

Principle Parts which might ignite an explosive atmosphere are immersed in oil or other non-flammable, insulating liquid so that gases and vapors above the oil level and outside the enclosure cannot be ignited by electric arcs or sparks generated below the oil level, or by hot residual gases from the switching process or by hot surfaces - e. g. on a resistor.

Important design parameters ‐ Stipulated, insulating liquids, e. g. oil

Protection of the liquid from contamination and moisture. ‐ Assurance and possibility of monitoring that the oil level is safe

- when heated up or cooled - for identification of leaks

‐ Restricted to non-portable devices.

Applications ‐ Large transformers, switchgear, starting resistors and complete starting controllers.

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Increased safety

Marking "Ex e" II 2 G in accordance with IEC 60079-0

Principle Additional measures provide a higher level of protection. This ensures reliable prevention of unacceptably high temperatures and sparks or electrical arcs, both on the internal and on the external parts of electrical equipment whose normal operation does not involve unacceptably high temperature sparks or arching.

Important design parameters ‐ For uninsulated, live parts, special protective requirements apply. ‐ Air and creep age gaps are made wider than is generally the case in industry. Special conditions

apply to the IP protection degree to be adhered to. ‐ For windings, their design, mechanical strength and insulation, higher requirements apply and the

windings must be protected from increased temperatures. ‐ Minimum cross sections are stipulated for winding wire, the impregnation and reinforcement of coils

and for thermal monitoring devices.

Applications ‐ Installation material such as junction boxes, connection cabinets for heating systems, batteries,

transformers, ballasts and cage motors. Non-sparking apparatus

Marking "Ex nA" II 3 G in accordance with IEC 60079-0

Principle The construction ensures reliable prevention of unacceptably high temperatures and sparks or electrical arcs, both on the internal and on the external parts of electrical equipment whose normal operation does not involve unacceptably high temperature sparks or arcing.

Important design parameters ‐ For uninsulated, live parts, special protective requirements apply. ‐ Air and creepage gaps are specified. ‐ Special requirements must be fulfilled by certain types of equipment.

Applications Installation material such as junction boxes, connection cabinets, rotating electrical machines, special fuses, lamps, cells and batteries, transformers and low energy equipment.


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Encapsulation

Marking "Ex m" II 2 G in accordance with IEC 60079-0 Marking "Ex mD" II 2 D in accordance with IEC 61241-0

Principle Parts that could ignite an explosive atmosphere by means of sparks or heat are potted so as to prevent ignition of the explosive atmosphere. This is achieved by encapsulating the components in a compound resistant to physical - especially electrical, thermal and mechanical - and chemical influences.

Important design parameters ‐ Encapsulation:

• Breakdown strength • Low water absorption • Resistance to various influences • Casting compound must be of the stipulated thickness all round • Cavities are only permitted to a limited extent • As a rule the casting compound is only penetrated by the cable entries

‐ The load on the components is limited or reduced ‐ Increased clearance between live parts

Applications ‐ Static coils in ballasts, solenoid valves or motors, relays and other control gear of limited power and

complete PCBs with electronic circuits. Hermetically sealed device


Principle The equipment may include cavities. It is constructed in such a way that the external atmosphere cannot enter.

Important design parameters ‐ Sealed by means of a melting process e. g.:

• Soft solder • Hard solder • Welding • Fusing of glass and metal

Applications ‐ Spark generating equipment

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Encapsulated device


Principle The equipment may include cavities which are fully enclosed similar to the encapsulation type of protection e. g. in a casting compound, so that ingress of the outer atmosphere is prevented.

Important design parameters ‐ It must be impossible to open the equipment during normal operation, internal free volume ≤100 cm³ ‐ External connections, terminals or cables must be available ‐ Cast seal must permit permanent operating temperature ≥10 K compared to the maximum operating

temperature ‐ It must not be possible for elastic seals to become mechanically damaged under normal operating

conditions; they must maintain their sealing properties over the service life of the equipment

Applications ‐ Contact systems, static coils in ballasts, solenoid valves or motors and complete PCBs with

electronic circuits. Sealed device


Principle The equipment may include cavities, which are fully enclosed similar to the encapsulation type of protection so that ingress of the outer atmosphere is prevented.

Important design parameters ‐ It must be impossible to open the equipment during normal operation, internal free volume ≤100 cm³ ‐ External connections, terminals or cables must be available ‐ It must not be possible for elastic seals to become mechanically damaged under normal operating

conditions; they must maintain their sealing properties over the service life of the equipment

Applications Contact systems, static coils in ballasts, solenoid valves or motors and complete PCBs with electronic circuits.


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Intrinsic safety

Marking "Ex i" II 2 G in accordance with IEC 60079-0 Marking "Ex iD" II 2 D in accordance with IEC 61241-0

Principle Intrinsically safe electrical equipment contains only circuits that meet the requirements of intrinsically safe circuits. Intrinsically safe circuits are circuits in which no spark or thermal effect occurring under the test conditions laid down in the standard can ignite the explosive atmosphere of subgroups IIA, IIB and IIC or of an air/dust mixture. The test conditions cover normal operation and certain fault conditions stipulated in the standard.

Important design parameters ‐ Use of certain components for electrical and electronic circuits. ‐ Lower permitted load on the components than in ordinary industrial applications with regard to

• voltage related to electric strength • current related to heat

‐ Voltage and current, including a safety margin, are kept permanently so low that no impermissible temperatures can occur, and, in the event of open circuit or short-circuit, sparks and electric arcs possess so little energy that they are unable to ignite an explosive atmosphere.

‐ An impression of this protection type is provided by the fact that explosive atmospheres of subgroup IIA require only a few hundred μW and those of subgroup IIC only 10μW for ignition.

Applications ‐ Measuring and monitoring instrumentation and control. ‐ Sensors working on the basis of physical, chemical or mechanical principles and at limited power. ‐ Actuators working on the basis of optical, acoustic and, to a certain extent, mechanical principles.

Energy limited circuit

Marking "Ex nL" II 3 G in accordance with IEC 60079-0

Principle These are circuits in which no spark or thermal effect occurring under the test conditions laid down in the standard can ignite the explosive atmosphere of subgroups II A, II B and II C or of an air/dust mixture. The test conditions cover normal operation and certain fault conditions stipulated in the standard. The permissible currents or voltages exceed those stipulated for the intrinsic safety type of protection.

Important design parameters ‐ The requirements to be fulfilled by the circuit and the loads on the components are lower than those

for the intrinsic safety type of protection. ‐ Also with regard to errors, lower requirements apply.

Applications ‐ Measuring and monitoring instrumentation and control. ‐ Sensors working on the basis of physical, chemical or mechanical principles and at limited power. ‐ Actuators working on the basis of optical, acoustic and, to a certain extent, mechanical principles.

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Restricted breathing enclosure

Marking "Ex nR" II 3 G in accordance with IEC 60079-0

Principle The enclosures are designed in such a way that the ingress of gases is restricted.

Important design parameters ‐ The powerloss in the enclosure may, if it contains sparking components, only lead to a temperature

increase compared to the surrounding of ≤10 K. ‐ Equipment with these enclosures must allow monitoring of the vapour tightness and tightness after

installation and maintenance. ‐ The allocation to the temperature class by the external surface temperature applies to all enclosures

with and without sparking components. ‐ It must not be possible for elastic seals to become mechanically damaged under normal operating

conditions; they must maintain their sealing properties over the service life of the equipment. ‐ Cast seals must permit a permanent operating temperature ≥10 K compared to the maximum

operating temperature.

Applications ‐ Switchgear, measuring and monitoring instrumentation and information systems and devices.


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7. Protection concept

Electrical Symbol Gas/Dust

Typical Zone(s)

IEC/EN Draft Only Due 2006 Standard (status at Jan 2006) Basic concept of protection

Gas Dust

Increased safety e 1,21 EN 60079-7 } EN 61241-1 No arcs, sparks or hot surfaces

Type “n” (non-sparking) nA 2,22 EN 60079-15

Flameproof D 1,21 EN 60079-1 } EN 61241-1 Contain the explosion, quench

the flame Type “n” (Enclosed break) nC 2,22 EN 60079-15

Quartz/sand filled Q 1,21 EN 60079-5

Intrinsic safety Ia/iaD 0,20 EN 60079-11 } EN 61241-11 Limit the energy of sparks and

surface temperatures Intrinsically safe Ib/ibD 1,21 EN 60079-11

Type “n” (Energy limitation) nL 2,22 EN 60079-15

Pressurised p/pD 1,21,22 EN 60079-2 EN 61241-2

Keep the flammable gas out

Type “n” (restricted breathing) nR 2,22 EN 60079-15 EN 61241-1

Type “n” (simple pressurised) nP 2,22 EN 60079-15

Encapsulation Ma/maD 0,20 EN 60079-18 } EN 61241-18

Encapsulation Mb/mbD 1,21 EN 60079-18

Oil immersion O 1,21 EN 60079-2

Enclosure tD 20,21,22 EN 61241-1 Protection by enclosure

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8. Apparatus groups & temperature classes for common flammable materials

Gas/Vapour Apparatus group

Temperature class

Dusts

Typical Ignition Temperature (°C)

Cloud Layer

Acetic Acid IIA T1 Aluminium 590 >450

Acetone IIA T1 Coal dust (lignite) 380 225

Acetylene IIC T2 Flour 490 340

Ammonia IIA T1 Grain dust 510 300

Butane IIA T2 Methyl cellulose 420 320

Cyclohexane IIA T3 Phenolic resin 530 >450

Ethanol (ethyl alcohol) IIA T2 Polythene 420 (melts)

Ethylene IIB T2 PVC 700 >450

Hydrogen IIC T1 Soot 810 570

Kerosene IIA T3 Starch 460 435

Methane (natural gas) (non-mining) IIA T1 Sugar 490 460

Methanol (methyl alcohol) IIA T2 Methyl ethyl ketone (MEK) IIB T2 Propane IIA T1 Propan-1-ol (n-propyl alcohol) IIB T2 Propan-2-ol (iso-propyl alcohol) IIA T2 Tetrahydrofuran (THF) IIB T3 Toluene IIA T1 Xylene IIA T1

9.Temperature Class (group II)

Maximum surface temperature

T. Codes

CENELC IEC

450°C T1

300°C T2

200°C T3

135°C T4

100°C T5

85°C T6

N.B. For Group I applications apparatus has rigid 150°C and 450°C limits rather than “T” classes.


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10. Marking To enable a piece of equipment to be readily identified it needs to be marked. For electrical equipment in hazardous areas the requirements for the label are carefully detailed in the certification standards and this section covers the sort of information that you will find on such labels. The marking must be legible and durable, permanently affixed onto the equipment to which it relates, and in a visible position. Equipment on which the label has fallen off or is illegible should be re-labelled after consulting the documentation or, if necessary, contacting the manufacturer (quoting the type of equipment and its serial number) for labelling details. The rules for the marking of systems, devices and components are uniformly defined in the standards relating to the general technical requirements. Because the European Community has agreed in the future to also formulate uniform requirements and to introduce a uniform classification for devices, systems and components, other than electrical equipment, the marking has also been unified. Additional symbols have been introduced. This has been defined in the Directive 94/9/EC on “Devices and protective systems for use in hazardous areas”. This Directive introduces electrical equipment, and for this reason the marking are prefixed by additional symbols. The marking on all devices and protective systems for hazardous areas must indicate the area of their designated use. The marking must indicate the following (see the symbol numbers on the example label):

N° details

Typical marking Meaning Variants

General informations

1 SCAME Product manufacturer -

2 Via Costa Erta 15 PARRE (BG) – ITALY

Manufacturer address -

3 Cod. 644.xxx-yyy Product designation -

4 2007 Year of manufacture Can be used with the last two year digit “07”

5

Conformity mark For category 1 and 2 must be followed by the

notified body number

6

Specific marking of explosive protection -

7 II Apparatus group

I: electrical apparatus for mines II: electrical apparatus for all remaining potentially

explosive atmosphere Depending on the dangerousness of the gas the

group II can be; IIA, IIB, IIC (IIC is the most dangerous)

8 2 Product category

1 for category 1 2 for category 2 3 for category 3

9 GD Type of explosive atmosphere

G: gas D: dust

GD: gas/dust

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N° details


Gas

10 Ex Specific marking according European Directive 94/9/EC

-

11 e Protection concept

Protection concept for gas: ‐ “d”: flameproof enclosure ‐ “px”: pressurized apparatus, level of protection “px” ‐ “py”: pressurized apparatus, level of protection “py” ‐ “pz”: pressurized apparatus, level of protection “pz” ‐ “q”: power filling ‐ “o”: oil immersion ‐ “e”: increased safety ‐ “ia”: increased safety, level of protection “ia” ‐ “ib”: increased safety, level of protection “ib” ‐ “nA”: type of protection “nA” ‐ “nC”: type of protection “nC” ‐ “nL”: type of protection “nL” ‐ “nR”: type of protection “nR” ‐ “mA”: encapsulation level of protection “mA” ‐ “mB”: encapsulation level of protection “mB”

12 Tx Temperature Class

(Max. Surface temperature of the enclosure)

Tx: Temperature Class (Group II): T1 = 450°C T2 = 300°C T3 = 200°C T4 = 130°C T5 = 100°C T6 = 85°C

Ta: range of ambient temperature

Dust

13 tD Type of protection for dust

Type of protection for dust: ‐ “tD”: protection by enclosure ‐ “pD”: type of protection pressurized “pD” ‐ “iD”: type of protection, intrinsic safety ‐ “mD”: type of protection, encapsulation protection

14 A21 Suitable Zone for Dust The equipment have been tested according EN 61241-1 method “A” or method “B”

15 IP66 Protection degree

IP6X: apparatus suitable for Zone 22 with presence of conductive dust IP5X: apparatus suitable for Zone 22 with presence of non conductive dust

16 Tyy Max. surface temperature of the enclosure

Tyy°C: max. surface temperature of the enclosure Ta: range of ambient temperature


21

N° details


Additional information

17a U ATEX components (not CE marked)

“U”: component (for example empty enclosure). The customer is required to certify the final assembly

17b X Particular condition for application

“X”: indicates in instruction sheet particular condition for application

18 Ta –xx°C to +xx°C Ambient temperature If not indicated the range is -20°C+40°C

Via Costa Erta 15 Parre BG ITALY

Cod. 644.xxxx-yyy Year xxxxS/N xxxxxxxxx V xxxx VSIRA08ATEX3042 I xxxx A

P max xxxx W

0051

Ex e II Tx Ta -xx° to +xx°CEx tD A21 IP66 Tyy°C II 2 GD

DO NOT OPEN WHEN ENERGIZEDIN PRESENCE OF EXPLOSIVE ATMOSPHERE

1 2

7

3 4

8

5

6

9

10

11

13

12

14

15 16

U

X

17a

17b

18

22

11. SCAME products range

ZENITH P Series Increased Safety Enclosures and Terminal Boxes for Applications in Hazardous Environments

ALUBOX-Ex Series Junction boxes in aluminium alloy

ADVANCE GRP Series Interlocked switch sockets outlets

OPTIMA-Ex Series Industrial plugs

ISOLATORS Series Switch-disconnectors


23

Zenith P Series

Specifications

Atex Code: II 2GD

Ex Protection type:

Ex e II Ex ia IIC Ex tD A21 IP6X T80°C (Ta -50°C+40°C if not marked)

Certificates: ‐ Empty Enclosure

Sira 08ATEX304IU IECEx SIR 08.0013U

‐ Terminal Box

Sira 08ATEX3042 IECEx SIR 08.0014

Operating Temperature Range: -60°C to +75°C (limits)

Temperature Class and Ambient: ‐ Standard

Ambient 40°C and T6 Class

‐ Optional

Ambient 60°C and T6 Class Ambient 60°C and T5 Class Ambient 75°C and T4 Class

Degree of Protection: IP66

Material:

• Glass Reinforced Polyester (SMC) –4 mm thickness

• Carbon Loaded for Anti-Static protection

• UV resistant according to ISO 4892-2

• Halogen Free and formulated RoHs directive

• Absolutely corrosion-proof • Seawater-proof

Surface Resistance:

Antistatic properties: < 10⁹ Ω The enclosures do not present a hazard from static electricity

Finish: Natural Black RAL 9005

Impact Resistance:

The enclosures are designed to withstand an impact of 7 J, and to be used in normal conditions of vibration

Code Enclosure size H W D

644.0100 75x80x55 75 80 55

644.0200 75x80x75 75 80 75

644.0110 75x110x55 75 110 55

644.0210 75x110x75 75 110 75

644.0120 75x160x55 75 160 55

644.0220 75x160x75 75 160 75

644.0130 75x190x55 75 190 55

644.0230 75x190x75 75 190 75

644.0140 75x230x55 75 230 55

644.0240 75x230x75 75 230 75

644.0350 120x220x90 120 220 90

644.0360 160x160x90 160 160 90

644.0370 160x260x90 160 260 90

644.0380 160x360x90 160 360 90

644.0390 160x560x90 160 560 90

Empty enclosures

Terminal box with glands

24

Component As “component” it is intended the empty enclosure composed by base, cover and gasket. It can be delivered with internal plate, continuity plate, earth stud, hinges, etc. The installer/customer is required to certify the final assembly Components are not CE marked Material of the enclosure: Resin SMC LS3806 R28C NERO Material of the gasket: Silicone rubber gasket without joint (Mesgo – MG8446N30) – (delivered in the cover)


Cod. 644.xxxx Year xxxxS/N xxxxxxxxxSIRA08ATEX3041U

0051Ex e II Ta -60° to +75°CEx ia IIC Ta -60° to +75°CEx tD A21 IP66 II 2 GD

Internal fixing: all internal fittings (e.g. DIN rail, backplate) shall be fitted using stainless steel fasteners and suitable antivibration washers Documentation: each “components” shall be accompanied by:

‐ the certificate of conformity ‐ instructions in the language or languages of the country in which the equipment or protective system

is to be used (availability in internet is not enough)

Label placed internally on the base Material of the label: Fasson Transfer PET Matt Chrome TOP/AL170 BG42 White. As option: Label plate in S.S. AISI316 Laser marking


25

Equipment As equipment it is intended the empty enclosure composed by base, cover and gasket completed with terminals. It can be delivered with internal plate, continuity plate, earth stud, hinges, holes, cable glands, etc. Scame certifies the final assembly. Material of the enclosure: Resin SMC LS3806 R28C NERO Material of the gasket: Silicone rubber gasket without joint (Mesgo – MG8446N30) – (delivered in the cover)



P max xxxx W

0051





P max xxxx W

0051



Tx e Tyy depends on Ta: Ta=40°C we can have T6 e T80°C Ta=60°C we can have T6 o T5 e T95°C Ta=75°C we can have T4 e T130°C

Label placed outside on the cover and internally on the base Material of the label: Fasson Transfer PET Matt Chrome TOP/AL170 BG42 White. As option: Label plate in S.S. AISI316 Laser marking

Year= year of production V= Rated voltage (V) I= Rated current P max= maximum dissipable power depending on Ta and T class (see following tables)

-50°C o –60°C to

+40°C, +60°C o +75°C

T4, T5 o T6

80°C, 95°C o 130°C

26

For T4 equipment the following sentence shall be reported on the label: WARNING - The cable entry point may exceed 101°C – Suitable precaution should be taken when selecting the cable For T5 equipment the following sentence shall be reported on the label : WARNING - The cable entry point may exceed 78°C – Suitable precaution should be taken when selecting the cable Internal fixing: all internal fittings (e.g. DIN rail, backplate) shall be fitted using stainless steel fasteners and suitable antivibration washers Terminals can be on rail or back-plate mounted If back-plate mounted they must be fixed with 2 screws The following distances shall be respected:

Voltage Creepage distance Clearance

250 6,3 5

400 10 6

500 12,5 8

630 16 10

800 20 12

1.000 25 14

SEE NOTE 8

SEE NOTE 8


27

Any suitable ATEX certified terminal can be used with the following limitations: ‐ terminals shall comply with EN 60079-7 (2006) ‐ terminals shall be fitted in accordance with the manufacturer’s instructions and any special condition

for safe use that are specified in their certificate ‐ Weidmuller WDU1.5 o WDU2.5 must be limited to 15°C ‐ T6 Equipment terminals shall be rated for a temperature minimum 80°C ‐ T5 Equipment terminals shall be rated for a temperature minimum 111°C ‐ T4 Equipment terminals shall be ceramic ‐ Ex i Equipment terminals shall be blue coloured

Maximum number of terminals to be fitted into the enclosure depends on:

‐ dimensions ‐ dissipated power

Where: Rt is the terminal resistance d3 tridimensional internal diagonal of the enclosure r20 is the resistivity of the connected conductor at 20°C I is the flowing current (if not specified, it is that of the terminal)

SCAME code

Enclosure size

Maximum Power Dissipation (W) for Cage Type Terminals

T6 Ta=+40°C

T6 Ta=+60°C

T5 Ta=+60°C

T4 Ta=+75°C

644.0100 75x80x55 2.5 1.3 2.5 2.55

644.0200 75x80x75 2.6 1.3 2.6 2.9

644.0110 75x110x55 3.2 1.35 2.85 3.6

644.0210 75x110x75 3.4 1.35 3 4.

644.0120 75x160x55 4.5 1.4 3.55 5.8

644.0220 75x160x75 4.7 1.45 3.6 6

644.0130 75x190x55 5.4 1.5 4 7

644.0230 75x190x75 5.5 1.55 4.05 7.2

644.0140 75x230x55 6.5 1.55 4.6 8.9

644.0240 75x230x75 6.6 1.6 4.7 9.2

644.0350 120x220x90 3.75 2.3 3.8 8.25

644.0360 160x160x90 3 2.5 3.2 6

644.0370 160x260x90 6.3 2.8 5.1 13.5

644.0380 160x360x90 7.2 2.75 N/A N/A

644.0390 160x560x90 11.7 3.8 N/A N/A

( )[ ]∑ +=n ttot IdRP 2

203ρ

28

SCAME code

Enclosure size

Maximum Power Dissipation (W) for Screw Type Terminals

T6 Ta=+40°C

T6 Ta=+60°C

T5 Ta=+60°C

T4 Ta=+75°C

644.0100 75x80x55 4.5 1.5 2.9 4.9

644.0200 75x80x75 4.6 1.5 3.1 5.2

644.0110 75x110x55 5 1.6 3.5 6

644.0210 75x110x75 5.1 1.65 3.8 6.4

644.0120 75x160x55 6 1.75 4.8 8.2

644.0220 75x160x75 6.1 1.8 4.9 8.4

644.0130 75x190x55 6.6 2 5.6 9.4

644.0230 75x190x75 6.7 2.05 5.7 9.85

644.0140 75x230x55 7.5 2.2 6.7 11.3

644.0240 75x230x75 7.6 2.25 6.8 11.6

644.0350 120x220x90 7 2 4.5 16

644.0360 160x160x90 6.4 1.7 4 14.5

644.0370 160x260x90 8.5 2.5 5.6 19.7

644.0380 160x360x90 7.4 2.75 N/A N/A

644.0390 160x560x90 11.2 4.2 N/A N/A Maximum power calculated with the above formula shall be less or equal to the maximum power indicated in the tables.

Enclosure size (HxWxD)

Top/Bottom sides A/C Left/Right sides B/D Rear side F M16 M20 M25 M32 M40 M16 M20 M25 M32 M40 M16 M20 M25 M32 M40

75x80x55 1 1 - - - 1 - - - - - - - - -

75x80x75 2 1 1 - - 2 - - - - - - - - -

75x110x55 3 2 - - - 1 - - - - - - - - -

75x110x75 6 3 2 1 - 2 - - - - - - - - -

75x160x55 5 4 - - - 1 - - - - - - - - -

75x160x75 10 5 3 2 - 2 - - - - - - - - -

75x190x55 6 5 - - - 1 - - - - - - - - -

75x190x75 12 6 4 3 - 2 - - - - - - - - -

75x230x55 6 4 - - - 1 - - - - - - - - -

75x230x75 12 6 4 2 - 2 - - - - - - - - -

120x220x90 14 9 4 3 - 4 2 1 1 - - - - - -

160x160x90 8 6 3 2 1 6 4 2 1 - 8 6 4 - -

160x260x90 16 12 6 4 3 6 4 2 1 - 16 12 8 - -

160x360x90 22 18 9 6 4 6 4 2 1 - 24 18 12 - -

160x560x90 36 28 14 8 6 6 4 2 1 - 36 28 20 - -


29

Drilling area

Enclosure size (WxHxD)

Top/Bottom sides A/C

W1xD1

Left/Right sides B/D

H2xD2

Rear side F H3xW3

75x80x55 48 x 34 28 x 28 60 x 48

75x80x75 48 x 54 27 x 48 60 x 48

75x110x55 80 x 34 28 x 28 60 x 80

75x110x75 80 x 54 27 x 48 60 x 80

75x160x55 130 x 34 28 x 28 60 x 130

75x160x75 130 x 54 27 x 48 60 x 130

75x190x55 160 x 34 28 x 28 60 x 160

75x190x75 160 x 54 27 x 48 60 x 160

75x230x55 90 x 34 (x2) 28 x 28 60 x 190

75x230x75 90 x 54 (x2) 27 x 48 60 x 190

120x220x90 180 x 58 60 x 52 105 x 180

160x160x90 110 x 65 84 x 56 140 x 110

160x260x90 210 x 65 84 x 56 140 x 210

160x360x90 310 x 65 84 x 56 140 x 310

160x560x90 240 x 65 (x2) 84 x 56 140 x 240 (x2) Clearances for standard gland sizes

Cable gland size a (mm)

Clearances b (mm)

16 32

20 39

25 46

32 58

40 68 Documentation: each “equipment” shall be accompanied by:

‐ the declaration of conformity ‐ instructions in the language or languages of the country in which the equipment or protective system

is to be used (availability in internet is not enough) Equipments must be CE marked

GLAND

CLEARANCE

a

b

30

Accessories Back plate in zinc plated steel Mounting bracket in stainless steel AISI 316 External hinges in plastic material Earth continuity plate (internal) in zinc plated steel – available as option in copper or brass Earth stud (stud, nut and flat washer) in brass – available as option in S.S. AISI 316

50 MIN

Final test If junction boxes are fitted with wiring each equipments shall be subjected to a routine dielectric strengh test.


31

ALUBOX-Ex Series

Versions

Enclosure

Mounting plate

DIN rail kit

‐ Junction boxes in aluminium alloy (for Zone 22) ‐ Suitable for outdoor use.

‐ Supplied with enclosure earthing kit.

‐ Use only non-sparking components and cable glands compliant with the ATEX directive.

Reference standards

EN 61241-0 EN 61241-1

EN 60079-0 EN 60079-15

Technical characteristics

Protection degree: IP66

Material: Aluminium alloy

IK degree at 20°C: IK08

Cable inlets: Blank sides

DIN rail fixing: Yes

Colour: RAL 7037

Ex classification

Atex Code:

II 3GD

Ex Protection type: Ex nA II Ex tD A22 IP66 T90°C U

Operating Temperature Range: -20°C +60°C

Maximum permissible surface temperature: T90°C

Impact Resistance: Low mechanical risk (4J)

CE Certificates: SCAME ATEX 01U

32

ADVANCE GRP Series

Versions with mechanical interlock

With switch-disconnector

With switch-disconnector and fuse

With fuse and switch-disconnector

With molded case circuit breaker with thermal magnetic trip unit

With molded case circuit breaker with thermal magnetic and residual current release trip units

Versions with electrical interlock

With contactor

Reference standards

EN 60309-1 EN 60309-2 EN 60309-4

EN 61241-0 EN 61241-1


Rated current: 125A

Rated voltage: 100÷690V~

Frequency: 50÷60Hz

Insulating voltage: 500/690V~


Operating temperature according to the reference standard: -25°C+40°C

Max. operating temperature: 60°C

Glow wire test: 850°C/960°C

Self-extinguishing UL94: V0

Material: Thermoset

Cable inlets: Top side max 3xM63 Bottom side max 2xM63

Switch-disconnectors: ABB OT 160

Fuse-carriers: NH00

Thermal magnetic protection: Molded case circuit breaker ABB Tmax T1B (16kA) with thermal magnetic trip unit TMD (adjustable thermal threshold 0,7…1 x In fixed magnetic threshold 10 x In)

Thermal magnetic protection: Molded case circuit breaker ABB Tmax T1B (16kA) with thermal magnetic trip unit TMD (adjustable thermal threshold 0,7…1 x In fixed magnetic threshold 10 x In) + residual current release trip units RC221/1 (adjustable residual current trip 0,03 - 0,1 - 3A and time limit for non-trip instantaneous)

Version with contactor: Contactor CL09 GE POWER CONTROL

Colour: Grey RAL 7037

Ex classification

Atex Code:

II 3D

Ex Protection type: Ex tD A22 IP66 T90°C




Impact Resistance: 7J

Material: Thermoset

CE Certificates: SCAME ATEX 02


33

OPTIMA-Ex Series

Versions

Plugs


Rated current: 125A

Rated voltage: 200÷415V~

Frequency: 50÷60Hz

Protection degree: IP66/IP67



Glow wire test: 850°C/960°C

Self-extinguishing UL94: V5

Material: Thermoplastic

Colour: Grey

Reference standards

EN 60309-1 EN 60309-2 EN 60309-4

EN 61241-0 EN 61241-1

Ex classification

Atex Code:

II 3D

Ex Protection type: Ex tD A22 IP66 T90°C


Maximum permissible surface temperature:

T90°C

Protection degree: IP66/IP67

Impact Resistance: 7J

Material: Thermoplastic

CE Certificates: SCAME ATEX 03

34

ISOLATORS Series

Versions

Surface mounting

Cable inlets

Enclosure 20A – 32A and 40A (105x150x82) ‐ Upper surface: 1xM20 + 1xM25 ‐ Lower surface: 1xM20 + 1xM25

Enclosure 63A – 80A and 100A (150x210x106) ‐ Upper surface: 2xM32 ‐ Lower surface: 2xM32

Enclosure 125A (315x264x122) 160A (410x315x150)

‐ Blank side

Reference standards

EN 60947-3


Polarity: 2P – 3P – 4P

Rated current: 20A – 32A – 40A – 63A – 80A – 125A – 160A




Glow wire test: 650°C

Material: Metal

Colour: Grey RAL 7015

Ex classification

Atex Code:

II 3D

Ex Protection type: Ex tD A22 IP65 T90°C U



UNDER DEVELOPMENT

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