IEC 61386-23:2021

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.