A common A2 type brass cable gland seals an unarmoured cable by compressing an elastomer insert around its outer jacket. A threaded brass body mounts the assembly at the enclosure. I would use “A2” as a starting point, then check the supplier’s current drawing. The component order, cable range, thread, accessories and approvals depend on the product.
Key takeaways
- Read an A2 assembly from the cable side to the enclosure side: cap, insert, body, entry thread, sealing washer when specified, enclosure wall, and locknut for a clearance-hole mounting.
- Match the cable’s finished outside-diameter interval to the declared sealing or clamping range.
- Keep an A2 compression gland separate from an armour gland, which has dedicated armour-gripping parts and an assigned electrical arrangement.
- Specify the brass grade, finish, elastomer, entry thread, thread length, cable range, accessories, and installation method rather than buying by the A2 name alone.
- The supplier’s drawing and instructions identify which parts fit together and how that particular gland is assembled.
What does the A2 designation identify?
A2 type cable gland is not a complete purchasing specification until you identify the maker, model, drawing and project convention. Here, I am describing the common brass compression design that acts on an unarmoured cable’s outer covering. Check the supplier’s drawing before applying that description to another A2 product. In the purchase schedule, add size, cable range, entry thread, accessories, cable construction and required performance alongside the maker, model and A2 name. This helps prevent two mistakes: choosing an insert whose range misses the cable’s outside diameter (OD), and choosing a compression gland where a dedicated armour grip is needed. I would start with the cable construction and list the layers that must be sealed, gripped, terminated or passed through. The armoured-versus-unarmoured gland guide covers that broader choice. This article follows the A2 parts and their contact points.
Read the common A2 construction from cable to enclosure
I find it useful to follow both the load path and sealing path from cable to enclosure. The cap advances on the body and moves the insert into its working shape. The insert contacts a defined area of the outer jacket. The brass body supports these parts, provides wrench flats and carries the male entry thread. At the enclosure, a specified washer may seal under the body shoulder, and an inside locknut secures a mounting through a clearance hole. A threaded enclosure entry has a different mounting detail and may need different accessories.
Before installation, confirm the actual model’s component order against its bill of materials, drawing, and instructions. Models can combine shapes, use different insert profiles, mount into a threaded wall, or require another accessory arrangement.
Compression cap
Compression cap is the threaded component that advances toward the gland body and loads the insert according to the product design. Its wrench flats provide a controlled tool surface. Check the cap-to-body thread, starting position, tightening method, and tool clearance. The cap should be associated with its matching body and insert in the bill of materials, especially when several cable ranges share the same nominal entry thread.
Elastomer insert
Sealing insert is the shaped elastomer part that contacts the cable jacket over a stated diameter range. I would check its part identity, material or compound designation, size code, orientation and permitted cable range against the current product record. Then measure the finished cable where the insert will seal. Conductor size does not tell you the jacket diameter, and ovality, ridges, damage, contamination and tolerance can affect contact.
Brass body and hex shoulder
The body connects the cable-side compression system to the enclosure entry. Its internal profile supports the insert; its external hex permits counter-holding; and its male thread provides the mounting interface. Drawings should state the thread designation, usable length, body across-flats dimension, shoulder diameter, bore or passage, and any seating feature. Its material and finish also affect whether the body suits the environment at that mounting point.
Entry washer and locknut
Entry interface is the assembled joint between the gland body, enclosure wall, seating face, and specified accessories. A washer or gasket can provide the designed face-sealing element. A locknut retains a gland through a clearance hole. For a threaded enclosure wall, the manufacturer may specify a different stack. Include coatings, earth tags, adaptors, reducers, or serrated hardware when the approved design uses them.
Keep A2 construction separate from armour-gland construction
A common A2 compression gland seals and retains the outer jacket of an unarmoured cable. An armour gland adds components designed to grip a specific armour construction and may participate in a defined protective-bonding arrangement. BS 6121-5:2005 makes the distinction useful by addressing selection, installation, and inspection of cable glands and armour glands, while BS 6121-1:2005 specifically covers requirements and tests for armour glands used with armoured cables.
| Construction question | Common A2 compression pattern | Armour-gland pattern |
|---|---|---|
| Cable construction entering the gland | Unarmoured cable with a sealable outer jacket | Cable with a defined armour layer plus its inner and outer coverings |
| Primary cable-side parts | Cap, elastomer insert, and body | Body plus armour cone, clamp ring, or another declared armour-gripping system |
| Dimension that drives selection | Finished outer-jacket diameter at the seal | Outer jacket plus armour and bedding dimensions at their assigned interfaces |
| Electrical detail | Established by the equipment and installation design | Includes the armour termination and its assigned bonding or earthing path |
| Preparation record | Jacket condition, insertion depth, and assembly sequence | Strip lengths, armour cut-back, wire arrangement, cone or clamp assembly, and seals |
If the drawing specifies steel wire armour (SWA), aluminium wire armour (AWA), braid, tape armour or a metallic sheath, choose a gland designed for that layer. An earth tag added to an A2-style compression gland does not provide an armour clamp. I would also check an armour gland’s cable ranges, enclosure-entry parts, seals, accessories and electrical arrangement separately.
Measure the five interfaces before choosing a size
An M20 entry does not define the cable aperture: two glands with that entry may have different insert ranges, bodies, thread lengths, and accessories. The M20 specification breakdown separates thread designation from cable fit. IEC 60423:2007 supplies conduit-system thread dimensions; the exact gland drawing controls the manufactured entry geometry.
| Interface to measure | Record from the cable, gland, or enclosure | Decision made with it |
|---|---|---|
| Cable at seal position | Minimum and maximum finished OD, tolerance, shape, and jacket condition | Select an insert range that covers the whole cable interval |
| Insert and body | Declared cable range, insert code, bore, and insertion depth | Match the correct insert to the correct body and cable |
| Cap-to-body joint | Thread identity, assembly position, and tightening instruction | Confirm compatible parts and provide tool access |
| Entry thread and wall | Thread designation, usable male-thread length, wall thickness, runout, and accessories | Establish whether the installed stack leaves the specified engagement |
| Internal space | Locknut across-flats size, component depth, cable path, conductor reach, and terminal clearance | Prevent interference and preserve the planned cable route |
The clamping-range guide provides a step-by-step OD comparison. For the enclosure side, calculate the installed axial stack rather than counting visible threads. The usable male-thread length must accommodate the wall and every specified accessory while leaving the engagement required by the controlled design.
Example: the same entry thread, two cable ranges
For example, an equipment schedule specifies M20 entries and a finished cable OD interval of 10.4–11.1 mm. Supplier A’s M20 A2 gland has an insert range that covers that interval. Supplier B’s M20 gland has a range that starts above 11.1 mm. Both may fit the enclosure thread, but only Supplier A’s candidate passes the cable-fit check. I would use the actual cable certificate or datasheet and current gland table for a purchase decision. These values are drawing-controlled examples.
Specify brass, finish, seals, and accessories as separate fields
“Brass” names a material family. It does not specify composition, properties, surface condition or corrosion response. The grade and finish—plain brass, nickel plating or another treatment—affect how the body behaves in the service environment. The industrial-grade cable-gland article explains the wider qualification process. Use the material and finish stated for the exact A2 model.
The insert and entry washer need suitable elastomers as well. Their temperature and chemical limits can differ from those of the brass body. Jacket chemistry, process fluids, cleaners, temperature cycling, compression set and exposure time can interact at the seal. Compression set is the deformation that remains after compression. For nickel plating, the nickel-plated brass gland guide helps organize the substrate, deposit, environment and inspection checks.
Complete the bill of materials with the precise accessories needed at each entry:
- gland body, cap, and matching insert size;
- entry sealing washer or gasket where specified;
- locknut for a clearance-hole mounting;
- adaptor or reducer when the approved entry and gland threads differ;
- earth tag, serrated washer, or bonding hardware where the electrical design assigns it;
- shroud where the product and installation documents call for one; and
- plugs for unused openings, selected under the enclosure’s own requirements.
Connect standards and approvals to the complete configuration
IEC 62444:2010 gives requirements and tests for cable glands as complete products. I would use the manufacturer’s current declaration, certificate, test record, drawing and instructions to identify the covered size, material, seal, cable range, mounting arrangement and classification.
The current IEC 60529:1989+A1:1999+A2:2013 consolidated version defines enclosure IP classifications and test conditions. That result depends on the gland and washer together with the wall, covers, joints, unused openings and installation conditions.
Hazardous-area service needs a separate approval check. The European Commission’s ATEX overview states that Directive 2014/34/EU covers equipment and protective systems intended for potentially explosive atmospheres. Match the gland to the equipment category, protection concept, certificate schedule, cable construction, entry type, temperature conditions, accessories and accepted instructions. An A2 label alone does not establish hazardous-area suitability.
Check the parts and assembly before installation
The supplied insert, body, cap, thread and accessories must match the exact model you intend to install. A similar-looking insert or locknut can have different dimensions. Compare the parts with the manufacturer’s drawing and instructions; a reference photograph cannot establish thread fit or cable range.
At installation, inspect the cable jacket at the seal position, confirm the measured OD, and check the entry seating face and hole or thread. Lay out the components in the documented order. Insert the cable to the defined position, engage threads cleanly, counter-hold the body where instructed, and tighten by the manufacturer’s method. Provide external cable support so routing load is managed by the installation rather than by the termination.
Open a technical review whenever one of these changes:
- cable supplier, construction, outer diameter, jacket, or service condition;
- gland body, cap, insert, material, finish, size, cable range, or thread length;
- washer, locknut, adaptor, reducer, shroud, earth tag, or bonding hardware;
- enclosure material, wall thickness, coating, hole, thread, seating face, or internal clearance;
- required IP code, hazardous-area classification, temperature, chemical exposure, or mechanical duty; or
- drawing, datasheet, certificate, test record, or installation-instruction revision.
Conclusion
I would turn the A2 name into a list of parts and interfaces before ordering the gland. Follow the cable through the cap, insert, brass body, entry thread, washer, enclosure wall and locknut. Then match the finished cable OD, mounting stack, material, finish, seal, accessories and required functions to that assembly.
Use the current drawing and installation instructions to match the cable and entry, then follow the assembly order for that gland. A change to the insert, cable, accessory or enclosure can affect fit, sealing or retention, even when the replacement still carries the A2 name.
A2 Type Brass Cable Gland FAQs
Is an A2 type brass cable gland for armoured cable?
A common A2 compression pattern is used with unarmoured cable and seals on the outer jacket. Armoured cable needs a gland construction declared for the exact armour type and dimensions, with dedicated armour-gripping parts and an assigned electrical arrangement. Confirm the meaning of A2 in the supplier drawing and project specification before ordering.
What parts are normally found in an A2 type brass cable gland?
A common assembly has a compression cap, elastomer insert, brass body with a male entry thread, and mounting accessories such as a face-sealing washer and locknut. A threaded enclosure entry may use a different accessory stack. Use the current bill of materials and assembly drawing for the exact product.
Does M20 identify the cable size for an A2 gland?
No. M20 identifies a metric entry-thread designation. The gland’s declared cable or sealing range is a separate value. Compare the cable’s complete finished-OD interval with that range, then verify the entry thread, usable length, wall stack, accessories, and internal clearance.
Is every A2 brass gland weatherproof or IP68?
No single rating follows from the A2 name. State the required enclosure IP code, then obtain product and assembly documentation for the exact gland, cable range, washer, wall, mounting method, and test conditions. The installed equipment must follow the covered arrangement and instructions.
What should an A2 gland purchase specification include?
Include the manufacturer and exact product code, A2 type reference, entry thread and usable length, cable range, body dimensions, brass grade, finish, insert and washer materials, accessory set, required product classifications, service conditions, drawing revision, and installation-instruction revision.
Sources and technical references
- BS 6121-5:2005, Code of practice for selection, installation and inspection of cable glands and armour glands, accessed 2026-09-23.
- BS 6121-1:2005, Armour glands: requirements and test methods, accessed 2026-09-23.
- IEC 60423:2007, Conduit thread dimensional requirements, accessed 2026-09-23.
- IEC 62444:2010, Cable glands for electrical installations, accessed 2026-09-23.
- IEC 60529:1989+A1:1999+A2:2013 consolidated version, Degrees of protection provided by enclosures, accessed 2026-09-23.
- European Commission, Equipment for potentially explosive atmospheres (ATEX), accessed 2026-09-23.