Overview
IEC 61386-23:2021 - "Conduit systems for cable management - Part 23: Particular requirements - Flexible conduit systems" specifies the particular requirements, tests and documentation expected for flexible conduit systems. It is intended to be used together with IEC 61386-1:2008 and IEC 61386‑1:2008/AMD1:2017 and updates the 2002 edition. A notable addition in this edition is Annex AA, which gives guidance on applying a constantly increasing compression force during tests.
Key topics and technical requirements
- Scope and linkage: Part 23 supplements and modifies the general requirements in IEC 61386‑1 for flexible conduit systems.
- Marking and documentation:
- Conduit shall be marked along its length at regular intervals (preferably every 1 m, maximum 3 m) or on labels/packaging where impractical.
- Manufacturers must document the minimum inside diameter, minimum bend radius and the classification code for the conduit system.
- Dimensions and threads:
- Threads must comply with IEC 60423.
- The minimum inside diameter is as declared by the manufacturer and is subject to measurement checks.
- Mechanical tests:
- Compression test: Annex AA provides guidance on a uniformly increasing compression force; example: for a 750 N test force an increase of 25 N/s (750/30) is required. Annex AA details tolerances for time and force.
- Flexing test: assemblies (conduit + terminating fitting) are tested on six samples - three at minimum declared temperature and three at maximum declared temperature (±2 °C). If the manufacturer limits flexing suitability to ambient, testing is at (20 ± 2) °C and the classification code uses “X” for the third digit.
- Test motion: oscillating member ±90° (total 180° ±5°), 5 000 flexings at (40 ±5) flexings/min, sinusoidal movement.
- Acceptance: no disintegration or visible cracks; the appropriate gauge must pass through the conduit under its own weight.
- Use limitation: very light flexible conduits are not considered adequate mechanical protection for building construction.
Practical applications and users
- Who uses IEC 61386-23: manufacturers of flexible conduit systems, product testers and independent laboratories, electrical designers, installers, procurement/specifiers, and certification bodies.
- Typical uses: specifying product performance (flexing, compression), verifying marking and dimensional claims, designing cable-management systems requiring flexible protection, and demonstrating compliance for procurement or regulatory requirements.
Related standards
- IEC 61386-1:2008 (General requirements) and IEC 61386‑1:2008/AMD1:2017 - mandatory companion documents.
- IEC 60423 - thread gauges and thread conformity for conduit fittings.
Keywords: IEC 61386-23:2021, flexible conduit systems, conduit systems for cable management, flexing test, compression test, conduit marking, minimum inside diameter, conduit classification, IEC 61386 series.