The question pertains to the selection of appropriate cable glands for use in Zone 1 explosive atmospheres, specifically when employing a cable with a metallic armouring and an outer sheath. According to IEC 60079-14:2013, Clause 7.5.2.3, when a cable with metallic armouring is used, the gland must provide effective electrical continuity of the armouring to the enclosure. Furthermore, Clause 7.5.2.4 addresses the sealing arrangements for cables. For cables with a thermoplastic outer sheath, a “barrier gland” (also known as a “flameproof cable gland” or “Ex d gland”) is typically required to maintain the integrity of the explosion-protected enclosure by sealing the cable’s outer sheath and preventing the ingress of flammable gas into the enclosure through the cable entry. This type of gland creates a seal around the outer sheath, and the armouring is terminated to ensure electrical continuity. Therefore, a barrier gland with appropriate sealing for the outer sheath and provision for armour continuity is the correct choice.

The question pertains to the selection of appropriate cable glands for use in Zone 1 hazardous areas, specifically concerning the ingress protection (IP) rating requirements when using non-armoured cables. According to IEC 60079-14:2013, Clause 7.3.2, for non-armoured cables, the cable gland shall provide a seal around the cable sheath to prevent the ingress of dust and moisture. The required degree of protection for equipment installed in Zone 1 is typically IP6X for dust and IPX5 for water, as per IEC 60079-0. While the gland itself might be rated higher, the critical aspect for non-armoured cables is ensuring the seal around the outer sheath achieves the necessary ingress protection. Therefore, a cable gland with an IP rating of at least IP6X for dust and IPX5 for water is mandated to maintain the integrity of the enclosure’s protection. The specific requirement for the seal around the cable sheath to prevent ingress of dust and moisture is paramount.

The selection of cable glands for use in Zone 1 hazardous areas, specifically for a flexible cable with an overall diameter of 18 mm and an unarmored construction, requires adherence to the principles outlined in IEC 60079-14. The standard mandates that for flexible cables in such environments, the gland must provide adequate sealing against ingress of dust and moisture and also offer mechanical protection. Furthermore, the gland must be suitable for the specific type of explosive atmosphere and the equipment it is connecting to. Considering the unarmored nature of the flexible cable, a gland that offers a “barrier” seal (often referred to as a “stopping seal” or “compound seal” in older terminology, or a “resin seal” or “epoxy seal” in practice) is typically required to prevent the ingress of flammable gas or vapor into the enclosure through the cable entry. This barrier seal is crucial for maintaining the integrity of the enclosure’s protection concept. The gland must also be rated for the correct ingress protection (IP) rating and suitable for the temperature range of operation. For a flexible cable with an 18 mm outer diameter, the gland’s sealing range must encompass this dimension. The requirement for a barrier seal is paramount for unarmored flexible cables in Zone 1 to prevent the migration of explosive atmospheres into the enclosure. Therefore, a gland specifically designed with a barrier seal, capable of accommodating an 18 mm outer diameter flexible cable, is the appropriate choice.

The fundamental principle guiding the selection of cable glands for use in Zone 1 hazardous areas, specifically when employing the ‘Ex d’ (flameproof enclosure) method of protection, is to ensure that the gland maintains the integrity of the enclosure’s protection against the ingress of explosive atmospheres. IEC 60079-14:2013, in its clauses pertaining to cable gland selection and installation, emphasizes the need for the gland to be suitable for the specific hazardous area classification, the type of cable used, and the enclosure’s protection concept. For ‘Ex d’ enclosures, the cable gland must provide a seal that prevents the passage of flammable gases or vapours into the enclosure. This is achieved through a combination of the gland’s construction and, crucially, the correct application of sealing compounds or packing materials within the gland to form a barrier. The gland must also be rated for the specific gas group and temperature class relevant to the Zone 1 environment. Therefore, a gland that is certified for ‘Ex d’ applications, designed to maintain the enclosure’s integrity, and correctly installed with appropriate sealing is paramount. The requirement for a gland to be suitable for the cable’s construction (e.g., armoured or unarmoured) and to provide effective environmental sealing against dust and moisture, in addition to preventing the ingress of flammable atmospheres, further solidifies the importance of a comprehensive and certified solution. The selection process must consider the gland’s ability to maintain the overall explosion protection of the equipment, which is directly linked to the ‘Ex d’ certification of the enclosure itself.

The core principle being tested here relates to the selection of appropriate cable glands for specific hazardous area applications, particularly concerning the ingress protection (IP) rating and the method of sealing. IEC 60079-14:2013, specifically in clauses pertaining to cable entries, mandates that the sealing arrangements must maintain the integrity of the equipment’s enclosure, especially concerning its IP rating. When a cable gland is used, it typically employs a sealing ring or cone that compresses against the cable sheath to prevent the ingress of dust and moisture. The effectiveness of this seal is directly related to the gland’s design and its ability to achieve the required IP rating for the enclosure it is installed in. For an enclosure marked with IP65, it signifies protection against dust ingress (first characteristic numeral ‘6’) and protection against water jets from any direction (second characteristic numeral ‘5’). Therefore, the cable gland’s sealing arrangement must be capable of achieving at least this level of protection when properly installed on the specified cable. A gland that relies solely on a mechanical compression of the outer sheath without a dedicated sealing ring or cone, or one designed for a lower level of ingress protection, would not meet the requirements for an IP65 enclosure. The selection of a gland with an appropriate sealing method, such as a neoprene seal or a similar elastomer, designed to create a tight barrier against both solids and liquids, is crucial. This ensures that the overall ingress protection of the equipment is not compromised by the cable entry. The question focuses on the *method of sealing* as the critical factor in maintaining the enclosure’s specified ingress protection.

The question pertains to the selection of suitable cable glands for use in Zone 1 hazardous areas, specifically when employing unarmoured, elastomeric-sheathed cables. According to IEC 60079-14:2013, Clause 7.5.2.3, for unarmoured cables with elastomeric sheaths, the cable gland must provide effective sealing against the ingress of dust and moisture into the enclosure. Furthermore, it must offer mechanical protection to the cable sheath and prevent the outer sheath from being drawn out. The gland’s design should ensure that the sealing ring (or equivalent) compresses the outer sheath to achieve the required ingress protection (IP rating) and mechanical retention. The gland must also be suitable for the specific type of cable and the environmental conditions. Considering these requirements, a gland that provides a “barrier seal” or “compound seal” is often specified for such cables to ensure a robust and reliable seal against the hazardous atmosphere, in addition to providing adequate mechanical support and strain relief. The term “barrier seal” implies a seal that creates a physical barrier against the ingress of flammable gases or vapours, which is paramount in Zone 1.

The question pertains to the selection of appropriate cable glands for use in Zone 1 explosive atmospheres, specifically when employing unarmoured, elastomeric-sheathed cables. IEC 60079-14:2013, Section 10.5.2, addresses the requirements for cable entries. For unarmoured cables, the standard mandates the use of cable glands that provide both sealing and mechanical retention. The sealing function is critical to prevent the ingress of flammable gases into the enclosure, thereby maintaining the integrity of the explosion protection concept. The mechanical retention ensures that the cable is securely held, preventing strain on the internal conductors and connections. When dealing with elastomeric sheaths, which can be softer and more prone to deformation than other materials, the gland’s design must ensure a robust seal without crushing or damaging the sheath. This typically involves an outer seal that compresses against the cable sheath and an inner seal or clamping mechanism that secures the armouring (if present) or the cable itself. For unarmoured cables, the gland must provide a seal around the sheath and a method to prevent the cable from being pulled out. Therefore, a gland designed for unarmoured cables, providing both sealing and mechanical retention of the sheath, is the correct choice. Other options are incorrect because glands for armoured cables are designed to clamp the armouring, which is absent in this scenario, making them unsuitable. Glands solely for sealing without mechanical retention would not adequately secure the cable. Glands for different protection concepts (e.g., intrinsically safe circuits) have specific requirements that may not be met by a general-purpose gland for Zone 1.

The question pertains to the selection of appropriate cable glands for use in Zone 1 hazardous areas, specifically concerning the ingress protection (IP) rating requirements when terminating cables with a metallic braid. According to IEC 60079-14:2013, Clause 7.3.2, when a metallic braid is used for earthing or screening purposes and is terminated within the gland enclosure, the gland must provide adequate ingress protection against dust and water. For Zone 1 environments, the standard generally requires a minimum IP66 rating for enclosures and associated equipment. When a metallic braid is present and requires termination, the cable gland must be designed to maintain this ingress protection. This typically involves a method for securely clamping and earthing the braid while ensuring the gland’s sealing integrity. The gland’s construction must prevent the ingress of dust and water, even under adverse environmental conditions, and the termination of the braid should not compromise this. Therefore, a gland specifically designed to accommodate and seal around the metallic braid, ensuring the overall assembly meets at least IP66, is the correct choice. Other options might offer some level of protection but fail to address the specific requirement of sealing around the braid to maintain the necessary ingress protection for a Zone 1 installation.

The question pertains to the selection of appropriate cable glands for use in Zone 1 hazardous areas, specifically when employing non-armoured cables with an outer sheath material that is resistant to oils and hydrocarbons. According to IEC 60079-14:2013, Clause 7.5.2.3, for non-armoured cables, the cable gland should provide a seal against the ingress of dust and moisture into the enclosure. Furthermore, for cables with an outer sheath resistant to oils and hydrocarbons, the gland’s sealing material (e.g., the elastomer used in the gland’s seal) must also exhibit compatibility with these substances to prevent degradation and maintain its sealing integrity. The standard emphasizes the importance of selecting glands that offer both mechanical protection and environmental sealing suitable for the specific cable type and the hazardous area classification. The primary function of the gland in this context is to maintain the integrity of the enclosure’s protection concept by providing a seal around the cable entry. Therefore, a gland designed for sealing non-armoured cables, with materials compatible with the cable’s sheath properties, is the correct choice.

The question pertains to the selection of cable glands for use in Zone 1 explosive atmospheres, specifically focusing on the requirements for maintaining the integrity of the enclosure’s explosion protection concept. IEC 60079-14:2013, Clause 7.5.1, addresses the selection and installation of cable glands. It mandates that cable glands must be suitable for the specific type of explosion protection and the environmental conditions. For an enclosure with Type of Protection ‘d’ (flameproof enclosure), the cable gland must provide a similar level of protection to the enclosure itself, particularly concerning the prevention of flame propagation. This means the gland must be correctly selected for the cable type (e.g., unarmoured, armoured) and the enclosure’s entry thread. Furthermore, the gland must be installed to ensure the sealing integrity and mechanical strength required by the standard. The critical aspect for ‘d’ enclosures is maintaining the flame path. A gland that is not correctly specified for the cable’s construction or the enclosure’s thread could compromise the flame path, leading to a failure of the explosion protection. Therefore, the most crucial consideration is ensuring the gland’s suitability for the specific enclosure type and the cable’s physical characteristics to maintain the integrity of the flameproof enclosure.

The correct approach involves understanding the requirements for maintaining the integrity of explosion-protected equipment when modifications are made. Specifically, IEC 60079-14:2013, Clause 7.1.1, addresses the need to ensure that any alterations do not compromise the original protection concept. When a cable gland is replaced with one of a different type or size, it is crucial to verify that the new gland maintains the same level of protection (e.g., Ex d, Ex e, Ex i) and is suitable for the specific hazardous area classification (Zone 0, 1, 2, 20, 21, 22) and the type of explosive atmosphere (e.g., gas group, temperature class). This includes ensuring proper sealing against ingress of dust and moisture, correct gland entry for the cable type, and adequate mechanical strength. If the replacement gland does not meet these criteria, or if the modification introduces a new potential ignition source or reduces the equipment’s ability to withstand explosion pressures or prevent ignition, then re-certification or re-assessment of the equipment might be necessary according to the applicable standards. The key principle is that any modification must not invalidate the original certification or the safety of the installation. Therefore, the most appropriate action is to ensure the new gland is certified for the specific application and maintains the original protection characteristics.

The core principle being tested here relates to the selection of appropriate cable glands for specific environmental conditions and explosion protection concepts, as detailed in IEC 60079-14. When selecting a cable gland for an enclosure with an Ex d (flameproof) enclosure, the gland must maintain the integrity of the flameproof enclosure. This typically involves ensuring that the gland itself is certified for use with Ex d enclosures and that its construction and installation method do not compromise the flamepath or the overall safety of the enclosure. Specifically, for a cable gland intended for use with a flameproof enclosure, it must be designed to prevent the passage of an internal explosion to the surrounding atmosphere. This often means the gland must have a suitable flamepath, be correctly tightened, and provide adequate sealing. The question focuses on the requirement for the cable gland to be certified for the specific enclosure type and to maintain the integrity of the explosion protection concept. Therefore, a gland certified for Ex d enclosures, which inherently addresses the requirements for preventing flame propagation, is the most appropriate choice. Other options might be suitable for different protection concepts or environmental conditions but do not specifically address the critical requirement of maintaining the Ex d integrity of the enclosure. For instance, while some glands might offer ingress protection (IP rating), this is a secondary consideration to the primary explosion protection requirement for an Ex d enclosure. The correct approach is to select a cable gland that is explicitly designed and certified to maintain the Ex d integrity of the enclosure, ensuring it can contain any internal explosion and prevent its propagation.

The correct approach involves understanding the requirements for selecting suitable cable glands for specific hazardous area applications as per IEC 60079-14. Specifically, when dealing with a Zone 1 hazardous area where a Group IIB explosive atmosphere is present, and the cable is of the unarmoured, multi-core type with a specific outer sheath material, the selection of the cable gland must ensure the correct ingress protection (IP) rating and mechanical strength. The standard mandates that for Zone 1, the enclosure or equipment connected to the cable gland must have a minimum IP rating of IP66. Furthermore, the cable gland itself must be suitable for the specific gas group (IIB in this case) and provide adequate sealing against the ingress of dust and liquids, as well as offering mechanical protection. For unarmoured cables, a gland that provides a “barrier seal” or “compound seal” is often required to prevent the migration of flammable gas into the enclosure through the cable’s interstices, especially if the cable’s outer sheath material is not inherently resistant to gas migration. The gland must also be rated for the appropriate temperature range and environmental conditions. Considering these factors, a gland with an IP66 rating, suitable for Group IIB, and designed for unarmoured cables with a barrier seal capability would be the most appropriate choice to maintain the integrity of the explosion-protected equipment and the hazardous area classification.

The fundamental principle guiding the selection of cable glands for Zone 0 environments, as per IEC 60079-14:2013, is to maintain the integrity of the enclosure’s explosion protection concept. For Zone 0, where ignitable atmospheres are present continuously or for long periods, the enclosure itself is typically designed with a high level of protection, such as flameproof (Ex d) or increased safety (Ex e). The cable gland must therefore provide a seal that prevents the ingress of the explosive atmosphere into the enclosure and, in the case of Ex d enclosures, maintain the flame path integrity. This necessitates a gland that offers a high degree of sealing, often achieved through compression of the cable’s outer sheath. The standard specifies that for Ex d enclosures, the cable gland must be suitable for the specific type of protection and the cable used. While Ex e enclosures also require careful gland selection to prevent the ingress of dust or moisture and to ensure proper termination, the absolute requirement for maintaining a flame path is paramount for Ex d. Therefore, a gland designed for a higher level of protection, such as that required for Ex d, would generally be considered suitable for Ex e, provided it meets all other installation requirements for the specific cable and zone. Conversely, a gland solely designed for Ex e might not inherently meet the stringent flame path requirements of an Ex d enclosure. The question probes the understanding of this hierarchy of protection and the critical role of the cable gland in preserving the overall safety of the installation in the most hazardous zones.

The question concerns the selection of appropriate cable glands for use in Zone 2 hazardous areas, specifically when employing a cable with a non-metallic outer sheath and a metallic armour. According to IEC 60079-14:2013, Clause 7.5.2.3, for cables with metallic armour or metallic braid, the gland shall provide electrical continuity between the armour/braid and the enclosure. Furthermore, Clause 7.5.2.4 addresses the requirement for sealing. For cables with a non-metallic outer sheath, a sealing arrangement (e.g., a diaphragm or packing) is required to prevent the ingress of dust and moisture into the enclosure, and to maintain the integrity of the enclosure’s protection concept. This sealing is crucial for maintaining the hazardous area classification and preventing potential ignition sources. Therefore, a cable gland that provides both effective electrical continuity to the metallic armour and a robust seal against the non-metallic outer sheath is necessary. This combination ensures the safety requirements for the installation are met.

The question pertains to the selection of appropriate cable glands for use in Zone 2 hazardous areas, specifically when employing a cable with a non-metallic outer sheath and a metallic armour. According to IEC 60079-14:2013, Clause 10.3.2, for cables with metallic armour, the gland must provide effective electrical continuity of the armour to the enclosure. Furthermore, Clause 10.3.3 addresses the sealing of cables, stating that the gland shall provide a seal against the ingress of dust and moisture. When dealing with a cable that has both a non-metallic sheath and metallic armour, the gland must be capable of terminating both elements effectively. A gland designed for metallic armour termination typically incorporates a mechanism to clamp and earth the armour. The sealing function is achieved by the gland’s internal sealing ring or diaphragm that compresses around the cable’s outer sheath. Therefore, a gland that provides both armour clamping and a sealing arrangement suitable for the cable’s construction is required. The correct approach involves selecting a gland that offers mechanical retention of the armour and a barrier against environmental ingress, ensuring the integrity of the explosion-protected equipment. This typically means a gland with an appropriate sealing system for the outer sheath and a method to secure and electrically bond the metallic armour. The other options are less suitable because they either do not address the metallic armour, or they propose sealing methods that are not specifically designed for the combined requirements of metallic armour and a non-metallic sheath in a hazardous area installation.

The question pertains to the selection of appropriate cable glands for use in Zone 1 hazardous areas, specifically when employing non-armoured cables with a thermoplastic sheath. According to IEC 60079-14:2013, Clause 7.5.2.1, for non-armoured cables, the cable gland must provide effective sealing and mechanical retention of the cable’s outer sheath. For cables with a thermoplastic sheath, the gland should be designed to prevent the ingress of dust and moisture and to ensure that the sheath is not damaged by the gland’s clamping mechanism. The gland must also provide adequate strain relief to prevent the conductors from being pulled out of their terminals. The sealing compound or sealing ring within the gland is crucial for maintaining the integrity of the enclosure’s protection concept, especially in Zone 1 where flammable gases may be present. Therefore, a gland that offers both effective sealing and appropriate clamping for the thermoplastic sheath, while also providing strain relief, is required. The specific type of gland that meets these requirements is typically a “barrier gland” or a gland with an integrated sealing system that can effectively seal around the cable sheath and provide mechanical support. The primary function is to maintain the integrity of the enclosure’s protection concept by preventing the passage of flammable atmosphere into the enclosure through the cable entry. This is achieved by the gland’s sealing mechanism and its ability to securely grip the cable’s outer sheath.

The question pertains to the selection of appropriate cable glands for use in Zone 1 hazardous areas, specifically when employing unarmoured, elastomeric-sheathed cables. According to IEC 60079-14:2013, Clause 7.5.2.3, for unarmoured cables with elastomeric sheaths, the cable gland must provide effective sealing against the ingress of dust and moisture, and crucially, it must offer mechanical protection to the cable’s sheath. Furthermore, the gland must ensure the integrity of the explosion protection concept of the equipment it is connecting to, which for Zone 1 typically involves flameproof enclosures (Ex d) or increased safety (Ex e). The gland must also provide adequate strain relief. Considering these requirements, a gland that offers both effective sealing and mechanical retention of the outer sheath, while also being suitable for the specific enclosure type (e.g., Ex d or Ex e), is necessary. A gland designed for unarmoured cables that provides a clamping effect on the outer sheath and a sealing barrier against the external environment, while maintaining the enclosure’s protection concept, is the most appropriate. This typically involves a gland with a sealing ring and a clamping mechanism that secures the outer sheath. The other options are less suitable: glands for armoured cables are designed to grip the armouring, which is absent; glands for specific cable types might not offer the required sealing or mechanical protection for elastomeric sheaths; and glands that only provide sealing without mechanical retention of the sheath would not adequately protect against mechanical stress or prevent the ingress of contaminants if the sheath is compromised.

The question pertains to the selection of appropriate cable glands for use in Zone 1 explosive atmospheres, specifically when employing a cable with a non-metallic outer sheath and a metallic armour. According to IEC 60079-14:2013, Clause 7.5.2.3, for cables with metallic armouring, the gland must provide effective electrical continuity between the armouring and the enclosure or equipment. Furthermore, Clause 7.5.2.1 specifies that for cables with non-metallic outer sheaths, the gland should provide a seal against the ingress of dust and moisture. When dealing with metallic armour, the gland must also ensure effective earthing continuity. Therefore, a cable gland that offers both a sealing function for the outer sheath and a means to establish electrical continuity with the metallic armour is required. Such a gland is typically referred to as an “Ex d” or “Ex e” gland suitable for armoured cables, ensuring both mechanical protection and electrical bonding. The requirement for effective sealing against the ingress of external elements is paramount for maintaining the integrity of the enclosure’s protection concept. The electrical continuity of the armouring is crucial for safety, as it provides a path for fault currents to be safely discharged, preventing the armour from becoming live. The selection must also consider the cable’s construction and the specific environmental conditions.

The core principle here relates to the selection of cable glands for use in Zone 2 hazardous areas, specifically when employing the “increased safety” (Ex e) protection concept for the connected equipment. According to IEC 60079-14:2013, for Ex e equipment, cable glands must be suitable for the specific protection concept of the equipment they are connecting to. While a cable gland certified for “flameproof enclosure” (Ex d) can often be used in Ex e applications, the reverse is not always true without further consideration. The critical factor is ensuring that the cable gland’s design and certification adequately maintain the integrity of the Ex e enclosure, particularly regarding the prevention of arcing or sparking that could ignite the explosive atmosphere. A gland certified for Ex d inherently provides a higher level of containment than typically required for Ex e. Therefore, using an Ex d certified gland in an Ex e application is permissible as it meets or exceeds the safety requirements. However, the question asks about the *most appropriate* selection for an Ex e equipment in Zone 2. While an Ex d gland is acceptable, a gland specifically certified for Ex e, or a multi-certified gland that includes Ex e, is generally considered the most direct and appropriate choice, as it aligns precisely with the protection concept of the equipment. The question implies a scenario where a choice needs to be made between glands with different certifications. The most suitable gland for an Ex e enclosure is one that is itself certified for Ex e, or a gland that is certified for multiple protection concepts including Ex e. This ensures that the gland’s design features (e.g., sealing, mechanical strength) are specifically validated to maintain the integrity of the Ex e enclosure under fault conditions that might arise within the hazardous area. The other options represent less suitable or potentially incorrect choices. A gland only certified for Ex i (intrinsic safety) would not be appropriate for an Ex e enclosure as it does not address the potential for higher energy levels or fault conditions within the enclosure. A gland certified solely for Ex nA (non-incendive) might be acceptable in some Zone 2 applications, but the Ex e certification is the most direct match for Ex e equipment. A gland certified for Ex p (pressurization) is designed for a different protection concept and would not be the primary choice for an Ex e enclosure. Therefore, a gland certified for Ex e, or a gland with a broader certification that includes Ex e, is the correct selection.

The question pertains to the selection of appropriate cable glands for use in Zone 2 hazardous areas, specifically concerning the ingress protection (IP) rating. According to IEC 60079-14:2013, Clause 7.1.2, for equipment installed in Zone 2, the enclosure shall have a minimum degree of protection of IP54. Cable entries, including cable glands, must also maintain this level of protection. Therefore, a cable gland selected for a Zone 2 installation must provide at least an IP54 rating to ensure the integrity of the enclosure against dust and water ingress, as required by the standard for this specific zone classification. The other options represent lower or higher levels of protection that are not the minimum required for Zone 2 according to the specified standard. An IP54 rating signifies protection against dust ingress (the ‘5’) and protection against water jets from any direction (the ‘4’).

The question pertains to the selection of cable glands for use in Zone 2 hazardous areas, specifically focusing on the requirements for maintaining the integrity of the enclosure’s protection concept. According to IEC 60079-14:2013, when an enclosure is protected by the “increased safety” (Ex e) method, any cable entry device, such as a cable gland, must also be suitable for Ex e applications to ensure that the increased safety is maintained. This means the gland itself must be designed and certified to prevent the occurrence of sparks or excessive temperatures under normal operating conditions and foreseeable abnormal conditions. While other protection concepts like flameproof (Ex d) or intrinsically safe (Ex i) have their own specific requirements for cable entries, for an Ex e enclosure, the cable gland must also comply with Ex e standards. Using a gland certified only for general industrial use or for a different protection concept (e.g., Ex d) would compromise the overall protection of the Ex e enclosure, potentially leading to ignition of the explosive atmosphere. Therefore, the correct selection is a cable gland certified for Ex e installations.

The selection of cable glands for use in Zone 1 hazardous areas, specifically for unarmoured cables, requires careful consideration of the ingress protection (IP) rating and the type of enclosure. According to IEC 60079-14:2013, for an enclosure with an IP65 rating, the cable gland must also provide at least an IP65 rating when properly installed. This ensures that the enclosure’s protection against dust ingress and water jets is maintained. Furthermore, the gland must be suitable for the specific explosive atmosphere group and temperature class. For unarmoured cables, the gland typically provides the necessary mechanical protection and sealing against the ingress of flammable gases or vapours. The sealing system of the gland, often referred to as the “seal” or “barrier seal,” is critical for maintaining the integrity of the enclosure’s protection concept. The correct installation technique, including proper tightening of sealing components, is paramount to achieving the specified IP rating and ensuring safety. Therefore, a cable gland with an IP65 rating, designed for unarmoured cables, is the appropriate choice to maintain the integrity of an IP65 enclosure in a Zone 1 environment.

The core principle being tested here relates to the selection of cable glands for specific hazardous area applications, particularly concerning the ingress protection (IP) rating and its relationship with the enclosure type of protection. IEC 60079-14:2013, in clauses pertaining to cable entries and glands, emphasizes that the cable gland must maintain the integrity of the enclosure’s protection concept. For an enclosure with a Type of Protection ‘d’ (flameproof enclosure), the cable gland, when used as a sealing arrangement, must provide a level of protection that is compatible with the enclosure’s requirements. Specifically, when a cable gland is used to seal the entry point of a cable into a Type ‘d’ enclosure, it must prevent the ingress of dust and moisture to a degree that would compromise the flameproof integrity or the internal atmosphere. The standard specifies that for outdoor or dusty environments, a minimum IP rating of IP6X for dust ingress protection is generally required for enclosures. Consequently, a cable gland intended for such an application, and which also serves as the primary sealing mechanism for the cable entry into a Type ‘d’ enclosure, must also meet at least this level of dust protection to ensure the overall integrity of the enclosure. Therefore, an IP66 rating, which signifies protection against dust ingress (6) and protection against powerful water jets (6), is a suitable and often required minimum for cable glands used in such demanding environments to maintain the enclosure’s protection against external ingress. Other IP ratings might be insufficient for dust protection, or might not offer adequate protection against water, which could indirectly affect the enclosure’s performance or lead to internal corrosion, potentially compromising safety. The selection of the correct IP rating for cable glands is crucial for maintaining the overall safety and operational integrity of electrical equipment installed in explosive atmospheres, as stipulated by the standard.

The fundamental principle guiding the selection of cable glands for Zone 0 environments, as per IEC 60079-14:2013, is to maintain the integrity of the enclosure’s explosion protection concept. For Zone 0, the primary protection concept is typically “intrinsic safety” (Ex i) or “flameproof enclosure” (Ex d). Cable glands must be certified for use in Zone 0 and must be compatible with the specific type of explosion protection employed by the equipment. The gland’s sealing mechanism (e.g., O-ring, packing) is critical to prevent the ingress of flammable atmospheres into the enclosure, and its material composition must be resistant to the specific environmental conditions and potential chemical interactions. Furthermore, the gland must provide adequate mechanical protection for the cable and ensure effective earthing or bonding if required by the installation design. The question tests the understanding of how the cable gland’s properties directly contribute to maintaining the safety of the electrical installation in the most hazardous of environments, emphasizing the need for certified components that uphold the equipment’s protection concept. The correct approach involves selecting a gland that is specifically designed and certified for Zone 0 applications, ensuring its material compatibility and sealing effectiveness, and verifying its suitability for the particular explosion protection method of the equipment.

The question pertains to the selection of cable glands for use in Zone 1 hazardous areas, specifically concerning the ingress protection (IP) rating requirements when a cable gland is used with a conduit system. According to IEC 60079-14:2013, Clause 7.5.2.3, when a conduit system is used to provide the required degree of protection, the cable gland itself, when fitted to the enclosure, must maintain that same degree of protection. For Zone 1, the minimum requirement for ingress protection against solid particles and water is typically IP6X for solids and IPX5 for water, as specified in IEC 60079-0. However, the critical aspect here is the *combined* protection offered by the conduit and the gland. If the conduit system is designed to achieve a higher level of ingress protection, such as IP67, then the cable gland, when installed, must also ensure this level of protection is maintained at the point of entry into the enclosure. Therefore, a cable gland rated for at least IP67 would be necessary to ensure the overall integrity of the enclosure’s protection against dust and water ingress, especially if the conduit system itself is designed to meet this standard. The question focuses on the *maintenance* of protection, implying the gland must match or exceed the protection provided by the conduit system it connects to.

The correct approach to determining the appropriate cable gland for a Zone 1 hazardous area installation, specifically for a cable with an outer sheath made of thermoplastic material and an internal metallic armouring, involves considering the ingress protection (IP) rating and the method of earthing the metallic armour. According to IEC 60079-14:2013, for cables with metallic armouring, the gland must provide effective electrical continuity between the armour and the gland’s earth connection. Furthermore, the gland must offer adequate ingress protection against dust and water, which is critical in Zone 1 environments. The gland’s design must also ensure that the thermoplastic outer sheath is securely gripped to prevent strain on the internal conductors and to maintain the integrity of the enclosure’s sealing. Therefore, a gland that provides both effective armour bonding and a robust seal for the outer sheath, typically achieved through a compression seal on the sheath and a dedicated connection point for the armour, is required. The selection must also consider the cable’s overall diameter and the enclosure’s entry thread size. The specific requirement for effective electrical continuity of the armouring is paramount for safety, as it ensures that any fault current can be safely conducted away. This necessitates a gland designed to make positive electrical contact with the metallic armour.

The selection of cable glands for use in Zone 1 hazardous areas, specifically for cables with metallic braiding, requires careful consideration of the gland’s ability to maintain the enclosure’s integrity and provide effective electrical continuity of the protective conductor. According to IEC 60079-14:2013, when a cable with metallic braiding is used, the gland must ensure that the braiding is effectively terminated to provide a low-impedance path for fault currents, thereby contributing to the overall safety of the installation. This involves ensuring that the gland provides a reliable connection to the braiding, which is often achieved through a clamping or crimping mechanism that makes positive contact with the metallic sheath. The gland’s design must also guarantee that the ingress protection (IP) rating of the enclosure is maintained, preventing the ingress of dust and moisture. Furthermore, the gland must be suitable for the specific type of explosive atmosphere and the temperature class of the equipment. The question focuses on the requirement for effective termination of the metallic braiding to ensure the continuity of the protective conductor, which is a critical aspect of earthing and bonding in hazardous areas to prevent the accumulation of static electricity and to provide a path for fault currents. Therefore, a gland designed for this specific purpose, ensuring both mechanical integrity and electrical continuity of the braiding, is essential.

The correct approach to determining the suitability of a cable gland for a specific Zone 1 hazardous area installation, considering the ingress protection (IP) rating and the potential for dust ingress, involves a thorough understanding of the requirements outlined in IEC 60079-14:2013. Specifically, Clause 7.5.2.1 addresses the selection of cable glands and their associated IP ratings. For Zone 1, where explosive atmospheres are present continuously or for long periods, the standard mandates a minimum IP rating for enclosures and associated equipment to prevent the ingress of flammable dust and moisture. While the question does not require a specific calculation, it tests the understanding of the principles governing the selection of cable glands based on environmental factors and the required level of protection. The selection process must ensure that the gland provides adequate sealing against both dust and water, which are critical for maintaining the integrity of the explosion-protected equipment. A gland with an IP66 rating signifies complete protection against dust ingress (the first digit, 6) and protection against powerful water jets (the second digit, 6). This level of protection is generally considered appropriate for Zone 1 environments where robust sealing is paramount to prevent the ingress of potentially ignitable materials or moisture that could compromise the explosion protection concept. Other IP ratings, while offering some protection, may not meet the stringent requirements for continuous or frequent presence of explosive atmospheres, especially concerning dust ingress which can be a significant hazard in certain Zone 1 classifications. Therefore, an IP66 rating is the most suitable choice to ensure the required level of safety and operational integrity in such demanding environments.

The core principle being tested here relates to the selection of appropriate cable glands for use in Zone 1 hazardous areas, specifically concerning the ingress protection (IP) rating requirements for cables entering enclosures. According to IEC 60079-14:2013, Clause 7.3.2, when a cable gland is used to maintain the integrity of an enclosure’s IP rating, the gland itself must be selected to provide at least the same degree of protection as the enclosure. For a Zone 1 environment, the typical minimum IP rating for enclosures is IP54. Therefore, the cable gland must also be rated for at least IP54 to ensure that the enclosure’s protection against solid objects and water ingress is not compromised. The selection of a gland with a lower IP rating, such as IP5X or IPX4, would not meet the requirement of maintaining the enclosure’s specified ingress protection. Similarly, a gland with a higher IP rating, while offering superior protection, is not strictly necessary to meet the minimum standard, though it would be permissible. The critical aspect is meeting or exceeding the enclosure’s IP rating.