IEC 61156-1:2023

Overview - IEC 61156-1:2023 (Multicore & symmetrical pair/quad cables)

IEC 61156-1:2023 is the fourth edition generic specification for multicore and symmetrical pair/quad cables for digital communications. It defines terminology, construction requirements and standardized test methods for communication cables used in LANs, data communication systems, industrial installations and customer premises wiring. The standard covers installation and work‑area cables defined in ISO/IEC 11801, and addresses cables intended to carry voltages and currents normally encountered in communications, including support for low‑voltage remote powering applications such as Power over Ethernet (PoE) (per ISO/IEC/IEEE 8802-3).

Key topics and technical requirements

The standard lays out comprehensive requirements and test procedures across these areas:

• Materials & cable construction
  • Conductor, insulation, cable elements, screening, sheath and identification.
• Electrical characteristics & tests
  • Conductor resistance, resistance unbalance, dielectric strength, insulation resistance, mutual capacitance and capacitance unbalance to earth.
  • Transfer impedance and coupling attenuation relevant to screened and unscreened designs.
  • Current‑carrying capacity for powered cabling.
• Transmission performance
  • Velocity of propagation, phase delay and delay skew (differential delay).
  • Attenuation, unbalance attenuation, characteristic impedance and return loss.
  • Crosstalk measurements: near‑end (NEXT), far‑end (FEXT), and alien (exogenous) crosstalk for bundled installations.
• Mechanical & environmental tests
  • Dimensional checks, tensile/elongation, bending, crush, impact, repeated bending, vibration and shock.
  • Ageing, damp heat, cold flex, solvent resistance, water immersion, flame propagation, halogen gas evolution, smoke and toxic gas emission.
• Test setups
  • Defined measurement configurations (baluns, termination, drum winding and bundling) to ensure repeatable lab verification.

Applications & who uses IEC 61156-1:2023

This standard is essential for:

• Cable manufacturers designing and qualifying multicore, pair and quad cables.
• Test laboratories performing standardized electrical, mechanical and environmental testing.
• Network designers and system integrators specifying cable performance for LANs, industrial Ethernet, structured cabling and PoE deployments.
• Procurement and compliance teams writing technical specifications and acceptance criteria.
• Standards developers and safety authorities coordinating cabling performance with building and fire codes.

Related standards

• ISO/IEC 11801 (generic cabling for customer premises wiring)
• ISO/IEC/IEEE 8802-3 (Power over Ethernet)
• Other parts of the IEC 61156 series (for specific constructions and performance classes)

By following IEC 61156-1:2023, stakeholders ensure consistent, testable cable performance for reliable digital communications and power‑over‑data applications.