> TECHNICAL > technical   Type A1 For unarmoured cable with an elastomer or plastics outer sheath, where the function of the gland is to secure the outer sheath of the cable. Type A2 As type A1, but with an IP66 seal between the outer sheath and gland. Type B For armoured or wire braided cable, where the function of the gland is to secure the armour or metallic braid and to provide electrical continuity between such armour or braid and the threaded fixing component of the gland. Type C For armoured or wire braided cable with elastomeric or plastics outer sheath. As type B but with an IP66 seal between the outer sheath and gland. Type E1 For armoured or wire braided cable with an extruded elastomeric or plastics inner sheath and elastomeric or plastics outer sheath and gland and etween the inner sheath and threaded fixing component.     The suffix for each type of protection shall be as follows. Single wire armoured W Pliable wire armoured flexible T Wire braided X Aluminium strip armoured Y Double steel tape armoured Z       Proof torque test Test one gland of each size and type. The gland shall be clean, new and without lubricant. Screw the threaded fixing component of the gland into a suitably tapped hole in a substantial block of steel. The thickness of the block shall be greater than the length of the thread on the component, and the hole pass right through the block. Assemble the gland with a short piece of the appropriate kind of cable of any diameter within the range of the gland. Tighten the gland with a manually operated torque spanner to the appropriate proof torque given in tables 1 to 6(BS 6121) ; apply the spanner first to the main body of the gland and then to each successive hexagonal component. Dismantle the gland and examine it. Ignore any seal distortion. Load test for type A glands Test one gland of each size and type. The gland shall be clean, new and without lubricant. Mount the gland as shown in figure 1. Secure a cylindrical low carbon steel mandrel, of the diameter specified in table 1(BS 6121) and any convenient length, in the gland; do this by tightening the gland with a torque spanner to a torque equal to 50% of the proof torque specified in table 1(BS 6121). The mandrel, which shall be clean, dry and polished, shall carry a platform on which weights may be placed. Mark the mandrel so that any movement relative to the gland can easily be detected. Load the mandrel with weights until the total tensile load of the mandrel, platform and weights is in accordance with table 1(BS 6121). Maintain the load for 6 hrs. Measure at the end of this period, the distance, if any, through which the mandrel has moved relative to the gland.     Test one insulated adaptor of each size. Mount the adaptor in a suitable gland plate as shown in figure 2. Tighten a suitable gland into the adaptor to enable the radial torque to be applied. Insert into the gland a mandrel of appropriate size, ensuring that the mandrel end does not enter the adaptor. Make arrangements to suspend weights from the mandrel. When calculating the radial torque to be applied assume that the weight of the mandrel itself acts halfway along its length. Apply the load for not less than 5 min. Finally, dismantle the assembly and inspect the insulated adaptor for signs of damage. Flammable mixtures can be classified under two main characteristics in respect of explosion protection; temperature of ignition by hot surfaces and the spark energy required to ignite the mixture. The spark energy of the ignition is also related to the intensity of the explosion. Classification of maximum surface temperatures in both North America and Europe are similar but vary slightly in the nomenclature used. The temperature classification is important to ensure that the correct equipment is matched to the flammable atmosphere that could potentially exist in an area. This will take into account such things as maximum ambient temperature and maximum operating voltage with a + 10% over voltage or an overload condition applied. In some types of protection such as Ex‘ d’or ‘nR’ the temperature classification is based on the outside temperature of the enclosure whereas in other types of protection such as Ex ‘e’or ‘nA’the temperature classification is based on the temperature of the internal components. (Unless otherwise specified on the rating plate it is assumed that the operating ambient temperature is in the range -20。C to +40。C in accordance with European standards) All gases are grouped according to their physical properties and details of their grouping can be found in either National or International codes of practice. Some examples of Gas Groups are shown below. GROUP GAS I(Mining) Methane(firedamp) IIA Industrial methane, propane, petrol & most industrial gases. IIB Ethylene, Town gas & other industrial gases IIC Hydrogen, Acetylene & Carbon Di-sulphide Ambient Temperature The ambient temperature is the surrounding temperature of the environment in which the equipment is installed, whether indoors or outdoors. For electrical equipment certified in Europe it is assumed that the ambient temperature in which the equipment may be operated is between -20。C and + 40。C. Some types of equipment are certified for operation outside this range and if so must be stated on the equipment label or certificate.” The ATEX directive (94/9/EC) came into force in April 1994 and was enacted into UK law in March 1996. It became a mandatory requirement in july 2003. Most of the products in this catalogue have an EC type examination certificate to the ATEX directive. ATEX covers both electrical and mechanical ignition hazards. Apparatus are divided into equipment groups (I for mining and II non-mining), source of ignition Gas (G) and Dust (D) and Categories 1, 2 and 3. The categories provide respectively, very high, high and normal levels of protection against ignition. The categories deliver the level of protection which is currently obtained by applying the existing protection techniques (Ex ‘d’, Ex ‘e’etc) and they also take into account other protection concepts proposed by manufacturers and considered by the notified (certification) bodies who produce EC type examination (ATEX) Certificates. The categories in practice are equated to suitability for Zones. The actual category of apparatus specified for a Zone depends on the overall risk assessment for a Zone. The zoning considers only the probability of the existence of an explosive atmosphere. It does not consider the consequential effects of an ignition taking place. Apparatus are marked with the grouping and category in addition to the marking required by the individual protection standards. Although this code change permits the use of products that have a Zonal classification, in a similar way to European practice, mixing of different forms of equipment approval across zones or divisions is not acceptable. e. g. 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/lEC methods in North America and vice versa The following table shows the basic relationships between the North American and European classifications.   Flammable gas always present > 1000 hrs/year Flammable gas normally present > 10 -1000 hrs/year Flammable gas not normally present < 10 hrs/year CENELEC/IEC Zone 0 (Zone 20 dust) Zone 1 (Zone 21 dust) Zone 2 (Zone 22 dust) ATEX Category 1G Category 1D Category 2G Category 2D Category 3G Category 3D US-NEC 505 Zone 0 Zone 1 Zone 2 US-NEC 500 Division 1 Division 1 Division 2 As can be seen from the table above, Division I covers both the European/IEC Zones 0 & 1. Therefore, care must be taken when using zone classified equipment in a Division1 area as to the suitability of the protection employed. Underwriters’ Labortory (UL) and Factory Mutual Inc(FM) are 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. Method of Protection Symbol Permitted Zone ATEX Category CENELEC Standard IEC Standard Protection Principle Flameproof Ex d 1 & 2 2 & 3 EN50018 79-1 Contain the explosion and prevent transmission Enclosed Break Ex nC 2 3 EN50021 79-15 Powder Filled Ex q 1 & 2 2 & 3 EN50017 79-5 Increased Safety Ex e 1 & 2 2 & 3 EN50019 79-7 No Arcs, sparks of hot surfaces or components Non Sparking Ex nA 2 3 EN50021 79-15 Intrinsic Safety Ex ia 0,1 & 2 1,2 & 3 EN50020 79-11 Limit energy of sparks and limit temperature of hot surfaces or components Ex ib 1 & 2 2 & 3 EN50020 79-11 Energy Limitation Ex nL 2 3 EN50021 79-15 Pressurised Ex p 1 & 2 2 & 3 EN50016 79-2 Prevent flammable gas coming into contact with hot surfaces and ignition capable equipment Encapsulation Ex m 1 & 2 2 & 3 EN50028 79-18 Oil lmmersion Ex o 1 & 2 2 & 3 EN50015 79-6 Restricted Breathing Ex nR 2 3 EN50021 79-15 Special Ex s 0,1 & 2 1,2 & 3 EHSR   Any proven method A major secondary protection parameter is the ingress protection of the electrical equipment. Moisture or dust if allowed to come into contact with electrical circuits could lead to either sparking or physical breakdown of the components and interfere with the protection method being used. In some cases the IP ratings for products in this catalogue have been carried out in accordance with EN 60529 (IEC 529) and have been witness tested by independent test laboratories. It will be noted that some products have both IP66 and IP67 ratings and this is because in some instances the IP66 requirment is more onerous than the IP67 requirement. Both the SX range and BPG range have also been tested to the Shell/ERA deluge specification. This is one of the most onerous water ingress tests and we designed specifically for electrical equipment which would be subject to deluge conditions, e.g. Ships decks, fire deluge areas. The following table shows the criterion for IP requirement to EN60529(IEC 529). First Digit Degree of Protection 0   No protection 1 Protection against ingress of large solid particles 2 Protection against ingress of medium sized solid particles 3 Protection against ingress of medium solid particles greater in thickness than 2.5mm 4 Protection against ingress of small solid foreign bodies greater in thickness than 1mm 5 Protection against ingress of dust in an amount sufficient to interfere with enclosed equipment. 6 Complete protection against ingress of dust. Second Digit Degree of Protection 0   No protection 1 Protection against ingress of vertically dripping water 2 Protection against ingress of water dripping at an angle of 75。to 90。 3 Protection against ingress of sprayed water 4 Protection against ingress of splashed water 5 Protection against ingress of water jets 6 Protection against ingress ofwater in heavy water 7 Protection against effects of temporary immersion 8 Protection against effects of indefinite immersion The IECEx is a single global certification framework to facilitate international trade in equipment and services for use in explosive atmosphere based on the IEC (International Electrotechnical Commission)’s international standard while maintaining the required level of safety : * Reduced testing and certification costs to manufacturer * Reduced time to market * International confidence in the product assessment process * One international database listing The goal is to help manufacturers reduce costs and time while developing and maintaining uniform product evaluation to protect users against products that are not in line with the required level of safety. So it should help industry to open up new markets from different conformity assessment criteria in various countries.The aim of the IECEx Scheme and its programs is to ease international trade of explosion protected equipment (termed Ex equipment) by eliminating the need for duplication of testing and certification while preserving safety. IECEx accepts the participation of Ex certification bodies and Ex test laboratories only after successful completion for the IECEx Assessment Process which also includes on-going surveillance each Ex candidate certification body and testing laboratory are subjected to the same IECEx assessment process utilizing the internationally established ISO/IEC standards and guides on conformity assessment supplemented with the IECEx technical guidance documents with world experts in the field of explosion-protection being appointed as IECEx Assessors. IEC (Marking : Ex d IIB T4) (EEx d IIB T4 : CENELEC Standard / Class, Zone 1, AEx d IIB T4 : American Standard (NEC 505) Type of Enclosure There are many factors to consider when selecting cable glands for industrial installations. Neglecting to pay due attention to some of these factors may cause unnecessary anxiety at a future point in time when the equiment and cable have either been forgotten to be ordered or it is discovered that they are the incorrect type or size at the very point when they are needed the most. Good advice would be to allocate some value added planning and preparation time to the subject of cable gland selection so as to avoid the great inconvenience which is likely to occur at a critical point in time. In the event that a user or contractor is in possession of a cable schedule that requires a cable gland selection and sizing process to be carried out, OSCG would be more than happy to assist in carrying out this process at no cost to the enquirer. Please contact OSCG for further information on this subject. Here is a summary of some aspects to carefully consider when selecting cable glands. ■ Identify the type of cable to be used. ■ Check the construction, size & material properties of the cable. When the cable is armoured, verify the following ■ Check the type and material of the cable armour ■ Check the short circuit fault current rating of the cable armour ■ Check the actual diameter of the inner bedding(where present) against this catalogue. ■ Check the actual diameter of the lead covering(where present) against this catalogue. ■ Check the actual size of the overall cable cable diameter against this catalogue. ■ Check the size and type of armour or braid against this catalogue. ■ Check any special environmental requirements in relation to corrosion protection. ■ Check the material of the mating electrical enclosures to eliminate dissimiar metals. ■ Consider whether any protective plating is required to be applied to the cable gland. ■ Check the type and size of the cable entry hole in the mating electrical equipment. ■ Check the ingress protection rating of the electrical equipment or site standard. ■ Check whether a single seal or double seal cable gland is required. ■ Check whether an entry thread seal is required for IP66(or IP67/68) conditions. ■ Check whether fixing accessories such as lock nuts and serrated washers are required. ■ Check whether earth tags are required. ■ Check whether shrouds are required. ■ Select a corresponding cable gland type from this catalogue. ■ For installation in hazardous areas, special considerations should be taken into account to ensure compliance with national or make the installation. ■ Select corresponding adaptors or reducers from this catalogue. ■ Check whether any stopping plugs are required to close unused cable entries. ■ Select corresponding stopping plugs from this catalogue.