20mm Coupler

20mm Coupler: Key Types and Applications

The 20mm Coupler is a fundamental component in conduit systems. It offers secure and reliable straight-through connections that extend conduit runs efficiently.

PVC Couplers: Manufactured from robust, impact-resistant uPVC with a high temperature tolerance (-5°C to +60°C). They provide a fast, push-fit connection, making them the standard choice for surface-mounted, embedded, and concealed indoor wiring applications.

Steel Couplers: Galvanised versions meeting BS 4568 and BS 31, and black-enamelled versions meeting BS EN 50086, are essential for industrial environments. They offer superior mechanical strength, corrosion resistance, and compliance with rigorous safety standards.

Specialist Couplers: Flanged couplers, manufactured from malleable steel with a BZP finish, are supplied with a BESA bush and lead washer for secure, watertight terminations. A specialised compression variant with an IP65 rating and a wide operating temperature range (-50°C to +135°C) is also available for demanding outdoor applications.

20mm Coupler: Key Specifications

20mm Coupler: Applications

PVC Couplers: Essential for extending runs of 20mm round PVC conduit in domestic and commercial electrical installations. They are used in wall chases, floor voids, and ceiling cavities. Their push-fit design ensures quick and secure joining.

Steel Couplers: Required for industrial installations, outdoor lighting, underground cable runs, and areas prone to mechanical impact. They provide a strong, robust connection that maintains the mechanical protection of the conduit system.

Flanged Couplers: Used in steel conduit systems where a secure, flanged termination is needed to connect conduit lengths to a box or enclosure.

Compression Couplers: Ideal for demanding outdoor and industrial use. They provide a sealed (IP65), high-strength join for metallic conduits that can withstand extreme temperatures (-50°C to +135°C) and provide high tensile strength.

20mm Coupler: Installation and Safety Considerations

PVC Coupler Installation: Ensure conduit ends are cut cleanly and free from burrs. Insert each conduit end firmly into the coupler until it fully engages. No glues or solvents are required. Use compatible conduit and couplers for the best fit.

Steel Coupler Installation: Screw the coupler onto threaded steel conduit ends. Ensure an earth lockring or bush is used where required to maintain earth continuity. Tighten securely for a strong mechanical join and electrical earth continuity.

Conduit Support: Ensure conduit is adequately supported with appropriate clips or cleats on both sides of the coupler to prevent strain on the fitting.

Indoor Use: Plastic/PVC couplers are designed for indoor use only. Do not use them in wet locations or where they will be exposed to direct weather unless specifically IP-rated.

Tool-free Assembly: Most plastic couplers offer a clip-on or push-in connection, allowing for rapid assembly.

Earthing/Continuity (Steel): When using steel conduit, the coupler plays a critical role in maintaining earth continuity throughout the system.

Storage: Store couplers in a clean, dry environment to prevent damage or corrosion prior to use.

20mm Coupler: Quality Assurance

The 20mm Coupler is a quality-assured component manufactured in compliance with BS EN 61386-21, BS 4607-5, BS 4568, or BS EN 50086. This guarantees its safety, electrical properties, and mechanical strength as a conduit accessory for electrical installations.

Leading brands like Centaur, RS PRO, Niglon, and Schneider Electric provide these critical fittings. They are typically backed by a 1-year manufacturer’s warranty, ensuring the long-term reliability of the entire containment system.