Cable Gland Selection: Cable Fit, Sealing, Armour and Earthing

Start With the Actual Cable Construction

Collect the manufacturer's current cable data: minimum and maximum overall diameter, inner-sheath or bedding diameter where a seal bears there, armour type and dimensions, outer-sheath material, screen or metallic-sheath details, mass, temperature range and expected mechanical load. Two cables with the same core count and conductor area can have different outside diameters.

IEC 62444:2010 provides requirements and tests for the construction and performance of complete cable glands. Project requirements may add enclosure, environmental, electrical or explosive-atmosphere obligations.

Match the Declared Sealing Range

The delivered cable diameter must fall within the gland manufacturer's declared sealing range. Leave practical allowance for cable tolerance, ovality and installation conditions rather than choosing at the extreme edge. Confirm whether the design seals the outer sheath, uses separate inner- and outer-sheath seals, a multi-hole insert, or a barrier compound.

Do not remove sheath layers or add tape merely to make an incompatible gland fit. Such field changes can defeat sealing, retention and certification.

Non-Armoured and Armoured Cables

A non-armoured gland normally provides sealing and retention appropriate to its declared design. For armoured cable, the gland must also match steel wire, steel tape, aluminium wire, braid or the actual metallic layer and its dimensions. Confirm the armour clamping range, continuity requirements and any fault duty assigned to the armour or bonding path.

Do not assume every metallic gland automatically provides an adequate protective-earth connection. Review the gland's declared electrical function, cable construction, enclosure interface and project earthing design.

Entry Thread and Enclosure Interface

Confirm the thread form, size, pitch and usable length; whether the enclosure has a threaded entry or clearance hole; wall thickness and material; and the required locknut, earth tag, serrated washer, sealing washer, adaptor or reducer. A correct cable-side seal cannot compensate for an incorrect enclosure entry.

Ingress protection is an assembly result. It depends on the gland, seal, enclosure surface, entry geometry, accessories, installation torque and cable diameter. Outdoor and washdown duty may also require drainage, suitable orientation, UV resistance and corrosion control.

Temperature, Materials and Compatibility

Check the lowest and highest service temperatures for the body, seals, accessories and any barrier compound. Include ambient conditions, enclosure heat, solar exposure and cable operating temperature. Brass, nickel-plated brass, stainless steel, aluminium and non-metallic products differ in corrosion, mass, bonding and compatibility.

The cable sheath and sealing element must remain compatible with oil, chemicals, cleaning agents and long-term heat. Avoid unacceptable galvanic combinations between gland, accessories and enclosure.

Hazardous Areas Need Additional Evidence

General industrial suitability does not establish suitability for an explosive atmosphere. IEC 60079-14:2024 addresses design, selection, installation and initial inspection of electrical installations in or associated with explosive atmospheres. The design must account for the protection concept, gas or dust group, temperature class, zone and certificate conditions.

Verify the current certificate and marking, permitted cable construction and diameter, sealing method, thread interface, temperature range and any specific conditions of use. Do not substitute a visually similar gland.

Installation Quality Controls

The work instruction should cover cable preparation, armour cut-back, clamp assembly, seal orientation, permitted lubricant, installation torque, bend clearance, locknut and bonding accessories, and inspection for sheath damage. Follow the instructions for the exact model: excessive tightening can damage the cable or seal, while insufficient tightening can reduce retention and ingress protection.