How to choose a cable gland: size, type and material for Saudi sites

By the Six Winds engineering team · Updated 2 November 2026

Step by step

1. Identify the cable constructionRead the cable code or cut face: unarmoured (NYY, H07RN-F, flexible), steel wire armoured (SWA, NYRY), aluminium wire armoured (AWA, single core), or braided (EMC screen, VFD cable). The construction decides the gland family: a single-seal gland for unarmoured cable, an armour-clamping gland (CW type outdoors, BW indoors) for SWA, an EMC gland for braided cable.
2. Measure the diametersMeasure the overall outer diameter of the cable with a caliper, and for armoured cable also the diameter over the inner sheath (bedding) under the armour. Use the maker’s cable data sheet when the cable is not yet on site.
3. Pick the gland size from the seal rangesEach gland size has a seal range for the outer sheath and, on armoured glands, a second range for the bedding. Both measured diameters must fall inside the ranges, ideally near the middle. Never choose from the conductor size alone: a 4 x 16 mm² SWA cable can need an M25 gland from one maker and an M32 from another.
4. Match the thread to the entryMetric ISO threads (M20 x 1.5, M25 x 1.5, M32 x 1.5, M40 x 1.5, M50 x 1.5, M63 x 1.5) are standard in Saudi projects; NPT appears on North American equipment and PG on older German equipment. Use a reducer or adaptor only when it is certified for the installation. Flameproof (Ex d) entries need at least five full threads engaged (IEC 60079-1), so order the long-thread version for thick walls and plates.
5. Choose the material and sealing for the siteIndoor dry panels: brass or nylon. Outdoors in Saudi Arabia (ambient above 50 °C, strong UV, sand): nickel-plated brass with a PVC shroud, IP66 and IP68 rated. Coastal plants in Jeddah, Yanbu, Jubail, Ras Al Khair and Rabigh, desalination and chemical areas: 316 stainless steel. Check that the seal elastomer is rated for the site temperature.
6. Hazardous areas: match the protection conceptFor Zone 1 and Zone 2 the gland is part of the certified equipment. Use an Ex d gland on flameproof enclosures, an Ex e gland on increased-safety enclosures (most industrial glands are certified Ex db eb for both), with the same gas group and ambient range as the enclosure, and a barrier (compound-filled) gland where IEC 60079-14 asks for one. Unused entries take a certified stopping plug.
7. Add the accessories and orderEarth tag (and a bonding lead) for armour earthing or where the enclosure is not metallic, locknut for clearance holes, serrated washer to cut through paint, PVC or LSF shroud outdoors, reducers only where allowed. Order by cable data: construction, outer and bedding diameter, gland thread, material, IP rating and, for Ex, the zone and gas group.

What a cable gland does

A cable gland (also called a cable connector or cord grip) is a mechanical fitting that terminates a cable at an enclosure, motor, luminaire or junction box. It holds the cable against pull-out and twist, seals the entry against dust and water, and on armoured cable clamps the armour and connects it to earth. Glands are specified in IEC 62444 and BS 6121, and for hazardous areas additionally certified to IEC 60079-0 with 60079-1 (Ex d) or 60079-7 (Ex e).

Because the gland is the weak point of an enclosure's IP rating and, in a hazardous area, part of the explosion protection, it is selected as carefully as the enclosure itself.

Step 1: identify the cable construction

The construction of the cable decides the gland family. Unarmoured cables need one seal on the outer sheath; armoured cables need a gland that clamps the armour and seals both the outer sheath and the inner bedding; braided (screened) cables need an EMC gland that bonds the braid 360 degrees.

Step 2: measure the cable and pick the size

The gland size is chosen from two diameters, not from the conductor cross-section: the overall outer diameter of the cable, and on armoured cable the diameter over the inner sheath (bedding) that the inner seal closes on. Both must lie inside the gland's published seal ranges. The table shows typical ranges for metric brass glands; makers differ by a millimetre or two, so the maker's own selection table is the final word.

Rules of thumb that save returns: a 4 x 16 mm² Cu XLPE/SWA/PVC cable is usually an M25, 4 x 35 mm² an M32, 4 x 95 mm² an M40, 4 x 185 mm² an M50, and 4 x 300 mm² an M63, but the actual diameters on the cable data sheet decide. When a diameter falls on the edge of a range, take the size where it sits nearer the middle of the range, or the smaller size when the seal must grip firmly against pull.

Step 3: thread type and length

The gland thread must match the enclosure entry: metric ISO (IEC 60423: M20 x 1.5, M25 x 1.5, M32 x 1.5, M40 x 1.5, M50 x 1.5, M63 x 1.5) is standard on IEC equipment and Saudi projects, NPT (1/2", 3/4", 1", 1 1/4", 1 1/2", 2") is standard on North American and some oil-and-gas equipment, and PG (PG 13.5, PG 16, PG 21) appears on older German machinery.

• Thread length: standard glands have about 15 mm of thread; a long-thread version (around 25 to 30 mm) is needed for thick cast walls, gland plates with gaskets and flameproof entries, where at least five full threads must be engaged (IEC 60079-1).
• Adaptors and reducers: change the entry size or thread form (M25 to M20, NPT to metric). In hazardous areas they must be certified and limited to one adaptor per entry.
• Clearance holes (unthreaded plates) need a locknut and, on painted plates, a serrated washer or earth tag for electrical continuity.

Step 4: material, plating and sealing

The gland material decides how long the seal and the earth path last in the site's climate. In Saudi Arabia the three enemies are heat (ambient above 50 °C on the surface of outdoor panels), ultraviolet light and salt-laden, sandy air on the coasts.

IP66 or IP68? IP66 means dust-tight and protected against powerful water jets; IP68 means protected against continuous immersion to the depth and time the maker states (for glands often 100 m for seven days). For outdoor panels, wash-down areas and buried pits specify both, IP66 and IP68, and check the seal temperature range: standard seals cover about −20 to +80 °C continuous, silicone seals go higher.

Step 5: hazardous areas (Ex d, Ex e, ATEX, IECEx)

In a hazardous area the gland is part of the certified equipment: it must carry its own Ex certificate (ATEX and/or IECEx) for the protection concept of the enclosure, the gas group and the ambient temperature range. An Ex d (flameproof) gland is used on flameproof enclosures and an Ex e (increased safety) gland on increased-safety enclosures; most industrial Ex glands are certified Ex db eb IIC Gb and Ex tb IIIC Db, so one gland covers both and dust.

• Barrier glands (filled with a setting compound around the cores) are required by IEC 60079-14 on flameproof enclosures in cases such as an internal source of ignition with a cable that is not substantially compact and circular, or gas group IIC installations; the project specification normally states when.
• Unused entries must be closed with certified stopping plugs of the same protection concept.
• Earthing: the armour must be earthed at the gland (earth tag or the enclosure's earth), and the gland body must maintain continuity through painted plates.
• Ambient: standard certification covers −20 to +40 °C; outdoor Saudi plants often specify +55 or +60 °C, so order glands with the wider marked range (Ta).

Our hazardous-area equipment guide explains zones, EPLs, gas groups and how to read an Ex marking.

Step 6: accessories

• Shroud (PVC or LSF): covers the gland nut and cable entry against sand, dust, UV and dripping water; standard on Saudi outdoor installations.
• Earth tag: a brass or stainless plate under the gland to bond the armour to the earth bar; use it on non-metallic enclosures or where the enclosure earth is not reliable.
• Locknut: secures the gland in a clearance hole; brass or nickel-plated to match the gland.
• Serrated washer: bites through paint to give electrical continuity between gland and plate.
• Entry thread sealing washer or IP washer: keeps the IP rating at the gland-to-plate joint.
• Reducers, adaptors and stopping plugs: as above; certified for Ex where used in hazardous areas.

Worked example: a feeder in Jubail

Cable: 4 x 25 mm² Cu XLPE/PVC/SWA/PVC 0.6/1 kV, outdoor, to a nickel-plated steel motor control panel on an open gland plate in a Zone 2 (IIA, T3) area of a petrochemical plant in Jubail Industrial City.

1. Construction: steel wire armoured, so an armour-clamping gland with a double seal (CW type).
2. Diameters from the cable data sheet: outer 24.2 mm, over bedding 19.6 mm. Both fall inside the M25 ranges (19.5 to 26 mm over armour, 15.5 to 20.5 mm bedding) and near the middle, so M25, not M32.
3. Thread: M25 x 1.5 into a gland plate with a gasket: standard thread length, with a locknut.
4. Site: coastal, salt-laden air and 50 °C ambient: 316 stainless steel body (nickel-plated brass is acceptable if the specification allows), IP66/IP68, seal rated to at least +80 °C.
5. Zone 2: gland certified Ex db eb IIC Gb / Ex tb IIIC Db, Ta range to +60 °C, no barrier required for Zone 2 with a compact cable (confirm against IEC 60079-14 and the project specification).
6. Accessories: LSF shroud, earth tag with 16 mm² bonding lead, serrated washer, certified stopping plugs for the two spare entries.

Ordering line: "Cable gland M25, CW type, 316 SS, Ex db eb IIC Gb, IP66/68, for SWA cable OD 24.2 / bedding 19.6 mm, with LSF shroud, earth tag, locknut and serrated washer."

Comparison: common gland types

What to send us for a quotation

The cable construction and size (for example 4 x 25 mm² Cu XLPE/SWA/PVC), its outer and bedding diameters or the cable data sheet, the entry thread and plate thickness, indoor or outdoor, the material, the IP rating, and for hazardous areas the zone, gas group and ambient temperature. Send the quantities per size and we quote certified glands with their accessories, datasheets and certificates, usually within 24 hours. Our cable gland selector gives a first answer from the cable diameter and location.

Common questions

This guide is general information. Final selection must follow the project design, the applicable standards and the maker's data.