IEC 60793-2-20:2015

Overview

IEC 60793-2-20:2015 is an international standard developed by the International Electrotechnical Commission (IEC) for optical fibres. It forms Part 2-20 of the broader IEC 60793 series, focusing specifically on product specifications for category A2 multimode fibres. The standard is applicable to three sub-categories of A2 multimode fibres: A2a, A2b, and A2c. These fibres are commonly incorporated into information transmission equipment and optical fibre cables, typically used for transmission distances up to 2 km.

This third edition represents a technical revision, introducing notable changes such as the replacement of Nath with NAff and refined measurement requirements for core diameter and numerical aperture.

Key Topics

• Scope: Defines requirements for A2a, A2b, and A2c multimode fibre types, as used in data communications and telecommunications.
• General Requirements: Based on IEC 60793-2, addressing essential optical fibre properties.
• Specification Structure:
  • General requirements as outlined in IEC 60793-2.
  • Category-specific requirements for all A2 fibres, detailed in the core standard text.
  • Sub-category requirements in dedicated annexes for A2a, A2b, and A2c fibres.
• Dimensional Requirements: Detailed limits on attributes such as core diameter, cladding diameter, coating diameter, and fibre length.
• Mechanical Requirements: Guidelines for tensile strength, proof stress, and resistance to environmental factors.
• Transmission Requirements: Key parameters such as attenuation coefficient, modal bandwidth, and numerical aperture (NAff).
• Environmental Performance: Test procedures for performance under damp heat, dry heat, and temperature changes, ensuring fibre reliability.

Applications

Category A2 multimode optical fibres specified by IEC 60793-2-20:2015 are widely used for high-performance information transmission in:

• Data centres and campus networking where cable runs do not exceed 2 km
• Telecommunications infrastructure in local and metropolitan area networks (LAN/MAN)
• Industrial automation systems requiring reliable, short to medium-distance fibre optic links
• High-bandwidth information transmission equipment, ensuring low attenuation and consistent modal bandwidth

The comprehensive specifications-covering physical, mechanical, and transmission characteristics-support manufacturers, network planners, and installers in ensuring consistent performance, long-term reliability, and interoperability in complex fibre optic deployments.

Related Standards

IEC 60793-2-20:2015 forms part of a larger framework for optical fibre standardization. Relevant related standards include:

• IEC 60793-2: General product specifications for optical fibres
• IEC 60793-1 series: Methods for measuring optical fibre attributes (geometry, attenuation, bandwidth, tensile strength, environmental performance, etc.)
• IEC 60794 series: Specifications for optical fibre cables
• IEC TR 62048: Guidance on reliability and power law theory for optical fibres

For compatibility and comprehensive guidance, users should consult the referenced standards within the IEC 60793 series when designing, specifying, or testing optical fibre systems.

Keywords: IEC 60793-2-20, optical fibres, category A2 multimode fibres, information transmission equipment, optical fibre cables, data communications, telecommunications, standard, NAff, attenuation, modal bandwidth, international standards, IEC