IEC 61755-3-31:2015

Overview

IEC 61755-3-31:2015 is an internationally recognized standard published by the International Electrotechnical Commission (IEC). This standard defines the dimensional limits and key parameters of angled physically contacting (PC) rectangular ferrule optical interfaces made from polyphenylene sulphide (PPS) material. It specifically applies to non-dispersion shifted single mode fibre optic connectors used in fibre-to-fibre interconnection systems. The standard supports the reliable and precise alignment necessary to maintain high-performance optical communications.

As part of the IEC 61755 series, IEC 61755-3-31 addresses the detailed connector parameters essential for ensuring compatibility, optical performance, and mechanical robustness in fibre optic networks. This standard complements the IEC 61754 series, which specifies ferrule interface dimensions and features for fibre optic connectors.

Key Topics

• Angled Polyphenylene Sulphide (PPS) Rectangular Ferrules: Defines the material specifications and design parameters for angled PPS ferrules to optimize physical contact and minimize back reflections in single mode fibre interfaces.
• Dimensional Limits: Establishes precise tolerances related to lateral and angular offsets, longitudinal positioning, and end-face geometry to ensure optimal fibre alignment and connection quality.
• Optical Interface Variants: Covers multiple interface variants (e.g., 1002, 1104, 1108, 1112), detailing their respective dimensional requirements for various fibre counts and connector designs.
• Physical Contact and Fibre Alignment: Includes parameters to achieve stable physical contact between fibres, essential for minimizing insertion loss and return loss in optical connections.
• Compliance with Fibre Categories: Specifies suitability for categories C, U, E, and O as described in IEC 61753-1, ensuring compatibility with various fibre classifications used in telecommunications and data networks.
• Testing and Measurement Methods: References relevant IEC normative documents for testing fibre position, polish angle, alignment pin deformation, and other critical connector interface properties.

Applications

IEC 61755-3-31:2015 applies primarily to the design, manufacturing, and quality control of fibre optic connectors that utilize angled PPS rectangular ferrules with non-dispersion shifted single mode fibres. Key practical applications include:

• Telecommunications Networks: Ensures low-loss, reliable fibre interconnection in long-haul and metro optical links.
• Data Centers and High-Speed Networks: Supports high-density multi-fibre connectors with stringent alignment requirements for minimal signal degradation.
• Passive Optical Networks (PONs): Enables consistent connector performance critical for subscriber-side fibre optics.
• Optical Test Equipment: Provides standardized interface parameters that facilitate accurate testing and measurement of fibre optic components.
• Military and Aerospace Communications: Enhances connector durability and performance under challenging environmental conditions.

By standardizing ferrule dimensions and interface parameters, IEC 61755-3-31 enables interoperability among manufacturers, reduces insertion loss and reflection issues, and supports the fast deployment of fiber optic communication systems worldwide.

Related Standards

• IEC 61755 Series: General series covering fibre optic connector optical interfaces and connector parameters for various fibre types.
• IEC 61754 Series: Defines fibre optic connector interfaces for different connector families such as MT, MPO, Mini-MPO, and MT-RJ connectors.
• IEC 61300 Series: Describes test and measurement procedures for fibre optic interconnecting devices, including polish angle and fibre position measurements.
• IEC 61753-1: Specifies performance categories (C, U, E, O) for fibre optic components, applicable in categorizing devices using IEC 61755-3-31 defined ferrules.
• IEC 60793-2-50: Covers product specifications for class B single mode optical fibres, relevant for non-dispersion shifted fibres.
• IEC 61300-3-52: Provides guidelines on alignment pin deformation constants for angled PC rectangular ferrules.

Conclusion

IEC 61755-3-31:2015 is critical for manufacturers and users of fibre optic connectors that employ angled PPS rectangular ferrules, ensuring they meet stringent dimensional and performance requirements for non-dispersion shifted single mode fibres. This fosters high-quality fibre-to-fibre interconnections with low optical loss and high reliability, crucial in advanced telecom, data communication, and high-performance network environments. Adhering to this standard helps maintain global interoperability and consistent connector quality in fibre optic systems.