ISO 4141-2:2019

Overview

ISO 4141-2:2019 specifies test methods and requirements for high-performance sheathed multi-core connecting cables used to link towing and towed road vehicles. The standard targets cables rated to temperature classes A and B (see ISO 6722-1) and augments the baseline tests in ISO 4141-1 with more stringent conditions and additional checks for coiled cable designs.

This part of ISO 4141 focuses on practical durability and functional performance under mechanical, thermal and chemical stress - essential for cable reliability in towing applications.

Key Topics

• General requirements: High-performance sheathed multi-core cables are subject to ISO 4141-1 requirements plus the additional or modified test conditions specified in Clause 5 of ISO 4141-2.

• Mechanical tests:

  • Impact: performed per ISO 4141-1 but at a freezing temperature of -20 ± 2 °C.
  • Cyclic bending: similar to ISO 4141-1 but increased to 10 000 cycles.

• Pressure and thermal tests: Pressure at high temperature is carried out according to ISO 14572, applying requirements for high-performance cables.

• Fluid compatibility of the sheath:

  • Representative fluids and conditions include ethanol (168 h), dilute sulphuric (battery) acid (48 h, density 1.275 g/cm³), lubrication oil No.1 (168 h, ISO 1817) and 50% zinc chloride solution (168 h).
  • Requirement: the sheath shall show no evidence of fracture or cracking after exposure.

• Coiled cable-specific tests (Clause 6):

  • Elongation by cable weight: extended coil length must not exceed twice the initial block length.
  • Cyclic extension: two sequences - 200 000 cycles to working length and 20 000 cycles to maximum admitted extension; test frequency (10 ± 5) cycles/min and conductor monitoring with (5 ± 0.5) A. No conductor breakage and no sheath cracking allowed.
  • Restoring force: after conditioning, restoring force when extended to max admitted length shall not exceed 250 N.
  • Cable sag limits: specified maxima vary by class and conditioning step (examples: 400 mm, 450/550 mm, 650 mm depending on the measurement stage).
  • Permanent elongation: percentage limits are specified per conditioning step (e.g., Class A/Class B limits: 30/30 %, 35/40 %, 40/50 %, 50/65 % across stages).
  • Class B peak-temperature sag: maximum sag after peak temperature cycles shall not exceed 750 mm.

Applications

This standard is used by cable manufacturers, automotive component testers and vehicle OEMs to:

• Verify mechanical and environmental durability of towing and coiled connection cables.
• Demonstrate compliance for product acceptance, procurement and design validation.
• Guide material selection for sheaths to resist chemicals, temperature and repeated flexing.

Related Standards

• ISO 4141-1 - Basic-performance sheathed cables (test methods and requirements)
• ISO 4141-3 - Construction, dimensions and marking of unscreened sheathed cables
• ISO 6722-1 - Single-core cable temperature classes and dimensions
• ISO 14572 - Round sheathed cables (pressure and high-temperature test methods)
• ISO 1817 - Rubber: determination of effect of liquids

For implementation details and exact test setups, refer to the full ISO 4141-2:2019 text and the referenced standards.