CE ATEX Requirements for Cable Glands

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ATEX
ATEX 95 Cable Gland Marking
Page 2 of 2
Additional Marking of ATEX Hazardous Area Cable Glands
The following two groups of symbols, in addition to what can be found on the previous page, are typically what you might find on an ATEX approved hazardous area cable gland :-


The first six digits above NE6 1BS refer to the manufacturer's postcode signifying the address of the manufacturing location.

The next two digits UK relate to the country of manufacture.
The next four digits -60oC to +130oC detail the approved temperature range of the product which happens to be a "positive" special condition of safe use.

The next two digits represent the European Community CE Mark, signifying that the product complies with all relevant European Normatives.

The next four digits 0518 indicate the QA Notified Body number. The first four digits EEx d detail the specific form of protection.

The next three digits IIC denote the Gas Group that the equipment or product certification covers.(In the example above the product approval has a Dual Certified status).

The next four digits EEx e detail the specific form of protection.The next two digits II denote the Gas Group that the equipment or product certification covers.

The next symbol is the trade mark of the Underwriters Laboratories of USA.
The next six digits Type 4X relate to the NEMA enclosure rating.

The next eight digits Oil Res II relate to the Oil Resistance rating according to UL 514B.Pages: 1 2

ATEX• What is ATEX ?• When does ATEX take effect ?• ATEX 95 Introduction• Manufacturer's Responsibility• Special Conditions for Safe Use• Products Covered by ATEX• Products Not Covered by ATEX• ATEX 95 Categories• ATEX 95 Cable Gland Marking• ATEX 95 Approved Cable Glands• ATEX 137• UK DSEAR Regulations 2002• EC Chemical Agents Directive (CAD)• ATEX - a Global Requirement ?• Up one level

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MARKING and INSTRUCTION MANUAL

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LOUDSPEAKERS INSTRUCTION MANUAL

CABLE GLANDS FAQs

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Technical information
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FAQ
The answer on frequently asked questions ...

Should cables, used in the Ex-zone, be marked according to the ATEX directive 94/9/EC ?
No, cables are no apparatus as described in this Directive. Cables are not considered as an ignition source assuming that they are electrically and mechanically adequately protected. Connecting apparatus following the ATEX95 directive is considered as being an installation (= domain of the social directive).

Cables conform to the Low Voltage Directive (73/23/EEC) are considered to be adequate for connecting apparatus as described in the ATEX95 directive.

Consequently a cable must not be labelled following the ATEX directive 94/9/EC.


Should intrinsically safe junction boxes (simple apparatus) be covered by an ATEX certificate ?
The definition of simple apparatus can be found in the harmonised European standard EN 50020 article 5.4 (= intrinsically safe equipment). Examples : switches, junction boxes, resistors, thermocouples, … This guideline is only applicable to electric equipment. These simple apparatus are excluded from the 94/9/EC directive because they have no intrinsic ignition source. In consequence, they don’t have to follow the conformity procedures and don’t have to be labelled following this directive.

Attention, this does not automatically implies that every simple apparatus is suitable for every application of the end user. Polyester boxes of category 1G for example should be antistatic. So, the user should decide for himself (risk analysis of the potential ignition sources) whether the simple apparatus is suitable for his application.


The same reasoning should be followed for non-electrical simple apparatus (plastic container, tube, chair,…). However, there is no definition for non-electrical simple apparatus, and in any case, end user should evaluate this separately.

In fact, the problem is being shifted from the economic to the social directive. In case of discussion the ATEX Standing Committee will take a decision, as it has been done for the valves operated by human force.


Can an apparatus in the safe zone be subject to the ATEX95 directive ?
Safety, control and regulating devices are located in the safe zone, but they are necessary to guarantee the safe working of an apparatus located in the Ex-zone having reference to danger for explosion.

Examples :
- motor protection switches for an EExe motor
- EExi barriers and modules
- central circuit board of a gas detection system
- electronic module to guard the temperature of a bearing
- PTC relay of an Ex motor

Safety, control and regulation devices are the only equipment that are subject to both the Low Voltage as the ATEX95 Directive.

Due to this double condition (always in combination with an apparatus in the Ex-zone and having reference to danger for explosion) it is avoided that every apparatus located in the safe zone and having an accidentally connection to the Ex-zone (for example by a cable), should be subject to the 94/9/EC Directive.

What is the meaning of the different characters in the EExn classification ?
EExn is based on the European harmonised standard EN 50021.

This protection method can be achieved in five different ways :
- non sparking apparatus (nA)
- housing with simplified overpressure (nP)
- apparatus with limited energy (nL)
- housing “restricted breathing” (nR)
- sparking apparatus (nC) of which the contacts are well protected, in another way than restricted breathing, apparatus with limited energy and simplified overpressure.

Apparatus that meet this standard (= category 3G) is only suited for use in zone 2 (gasexplosions). There is no automatic relation with a possible installation in zone 22 (dustexplosions), for which apparatus of category 3D are needed.


Can a user assemble an apparatus himself, based on componentcertificates (“U” at the end) ?
Components are parts, essential for the safe working of apparatus and safety systems, but not having an autonomic function.

Examples :
- connection terminals
- empty flameproof enclosures
- push buttons, signal lamps, A-meters,…
- ballasts for fluorescent lighting
- Ex MCB’s, relays

Components following the ATEX95 Directive should not be marked CE !

Indeed, they can’t be subject to all tests described in the Directive and matching Cenelec standards. This is the reason why component certificates (with “U” at the end) don’t mention the temperature class. The certificate or the manual states the final temperature class should be determined at a (later) installation in a housing.

Even an empty housing (= also a component) is certified without temperature class, since the manufacturer is not aware of what will be built in by the customer at a later time.

Unlike for example the Low Voltage Directive, an assembler can not rely on the CE’s of the components. This is why the directive demands a complete certificate of a Notified Body for zones 1 and 21 (categories 2G and 2D). In principle, self certification is allowed for zones 2 and 22. But how can an assembler determine the final temperature class when these of the different parts are not known ?

In practice, an assembly of components becomes an apparatus as meant in the directive.

When an end-user builts himself an apparatus, he is automatically considered as being a manufacturer which implies all his responsibilities and duties.


Can an EExd cable gland be used in an EExe application ?
Flameproof cable glands (EExd – EN 50018) and glands of increased safety (EExe – EN 50019) are being tested following 2 different standards.

As an increased safety gland can not be used in an flameproof housing, so can flameproof cable glands not automatically be used in an EExe housing.

For an EExe application, EExe glands should be used at any time.

A so-called dual-certified gland with marking EExde may be used in both applications.


Which documents are to be supplied by the manufacturer ?
A manufacturer is only obliged to deliver the declaration of conformity (CE-declaration) and the relevant installation and maintenance instructions.

The supply of the EC type certificate is not a legal obligation. Nevertheless, this contains a lot of additional information that often can’t be found on the documents to be supplied legally.


Should apparatus of group II always be marked with A, B or C ?
Only for the protection methods flameproof housing (EExd) and intrinsic safety (EExi) electric apparatus of group II are divided in gasgroups IIA, IIB or IIC.

This subdivision is based on the maximum experimentally defined gap (MESG) for flameproof housings and the minimum ignition current (MIC) for apparatus of intrinsic safety.

Examples :
- junction box increased safety with marking EEx e II T6
- junction box intrinsic safety with marking EEx ia IIC T6
- flameproof housing with marking EEx d IIB T3
- housing with overpressure with marking EEx p II T4
- magnetic valve with marking EEx em II T5

Apparatus with marking IIC have the most severe conditions. This means that IIB apparatus are also suited for IIA applications, and IIC apparatus are also suited for applications in need of IIA or IIB.


Is an authorized assessment organisation the same as a Notified Body as referred to in the directive 94/9/EC ?
A Notified Body following the Directive 94/9/EC is not to be confused with an authorized assessment organisation.

The last one does only an independent inspection on site before starting up the installation. So there is no judgement of compliance to the directive needed for the installation itself, on condition that the used apparatus and assemblies have had a proper judgement.

An authorized assessment organisation can not execute a product inspection nor deliver an ATEX certificate following the Directive 94/9/EC.


Why are cable glands of British make in most cases not suited for IIC applications?
According to EN 50018 (Annex C : C.2.1.1) glands with elastomeric sealing rings are divided in 2 groups.
The first group has sealing rings with a minimum uncompressed axial height of 20 mm for circular cables of diameter not greater than 20 mm, and a minimum axial height of 25 mm for circular cables of diameter greater than 20 mm. These glands have the advantage of interchangeable sealing ring, within the range of one gland type (f.e. M25).


The second group has short sealing rings, with a minimum uncompressed axial height of 5 mm, and with every gland type there is only one compatible sealing ring. These glands are not suited for IIC housing with an internal volume greater than 2 litres.

To warn the user about this restriction, an 'X' is added to the relative certificate, which means there are special conditions for use.
Most British cable glands are part of the second group.


When are round () and when are square [] brackets used in the classification code?
An intrinsically safe circuit consists of an intrinsically safe apparatus and a so called associated apparatus. All current circuits of an intrinsically safe apparatus are intrinsically safe, thus the apparatus can be placed within the Ex-zone.
For example : IS magnetic valve of category 1G with marking EEx ia IIC T6
Associated apparatus contain both intrinsically safe and non-intrinsically safe circuits. They are developed in a way that the non-intrinsically safe circuits don’t affect the intrinsically safe circuits. Thus, they should always be placed in the safe zone. Brackets are used to make this clear.
For example : galvanic isolator of category (1)G with marking [EEx ia]IIC
Square brackets are used in the classic Cenelec classification of associated apparatus while round brackets are used to define the category.

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