IEC 61754-31:2016

Overview

IEC 61754-31:2016 is an international standard issued by the International Electrotechnical Commission (IEC), defining the standard connector interface dimensions for the two way and four way Type N-FO fibre optic connector family. This standard is part of the broader IEC 61754 series focused on fibre optic interconnecting devices and passive components, specifically addressing connector interface specifications. The Type N-FO connectors utilize spring-loaded ferrules housed within circular plug and socket sets, providing reliable, precise alignment for fibre optic connections in advanced communication networks.

Key Topics

• Connector Family Description
  The Type N-FO family includes both two way and four way circular plug connectors and sockets.

  • Two Way System: Features two spring-loaded ferrules with a fiber pitch of 3.0 mm.
  • Four Way System: Features four spring-loaded ferrules arranged in a row, with a fiber pitch of 2.5 mm.

• Coupling Mechanism
  Both types use a threaded coupling nut for secure connection, designed to be tightened within a torque range of 1 Nm to 2 Nm. The plug shell features a keyway that aligns with a corresponding key in the socket, ensuring proper orientation.

• Ferrule and Endface Specifications
  The connectors employ 1.25 mm diameter non-angle polished ferrules. Resilient sleeves housed inside plug connectors align the ferrules accurately to maintain optical performance.

• Standardized Interfaces
  The standard defines detailed mating interfaces for:

  • Two way plug connectors
  • Two way socket connectors
  • Four way plug connectors
  • Four way socket connectors

• Intermateability and Dimensions
  Tables and illustrations within the standard provide precise dimensional specifications for plug and socket connectors, endface geometry, ferrule grades, and pin gauge dimensions, ensuring intermateability within the Type N-FO family.

• Normative References
  The standard references related IEC documents such as IEC 61754-1 for general connector interface guidance and IEC 61755-3 series for connector optical interface parameters.

Applications

The IEC 61754-31 Type N-FO connector family is critical for applications requiring robust, standardized fibre optic interconnects, including:

• Telecommunication networks – high-speed data transmission requiring precise fibre alignments.
• Data Centers – modular installations utilizing multi-fibre connectors for efficient rack-to-rack cabling.
• Industrial Automation – systems demanding stable fibre connections that can withstand twisting and environmental stresses.
• Broadcast and Medical Equipment – sectors needing reliable optical connectivity for signal transmission.
• Fibre Optic Equipment Manufacturing – ensuring compatibility and interchangeability of connectors and components.

Related Standards

• IEC 61754-1: Fibre optic connector interfaces – General and guidance applicable across multiple fibre optic connector families.
• IEC 61755-3: Connector optical interfaces covering parameters for non-dispersion shifted single mode physically contacting fibres, complementing the physical interface definitions of IEC 61754-31.
• Other parts of the IEC 61754 series define interfaces for different fibre optic connector families, providing comprehensive global standards for connector design and interoperability.

Keywords: standard connector interface dimensions, two way Type N-FO connector, four way Type N-FO connector, fibre optic connector interfaces, IEC 61754-31, fibre optic interconnecting devices, passive components, fibre optic connectors, threaded coupling nut, ferrule alignment, spring loaded ferrules, optical connector standards, fibre optic plugs and sockets.