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Low Macrobend Loss Fibers

Splicing compatibility

The selected G. 657A1 fiber from Tyco Electronics will guarantee full splice compatibility (both fusion and mechanical) with existing installed G. 652 fibers. No changes to fusion splicing parameter settings for core alignment are required.

Issues seen with bend insensitive fibers

• OTDR traces will show strange effects (gainers or higher losses) when mixing fiber types in connections or splices! Non-trained installers might make wrong conclusions about the splice loss or connector loss quality!

Attenuation measurement with OTDR in lines with mixed fiber types

Bend insensitive fibers are more and more used in the distribution network. When using OTDR measurement it is necessary to take the following information into account...

Assume the following situation

Low Optical Bend Loss Fibers

Attenuation measurement with OTDR in lines with mixed fiber types

Attenuation measurement with OTDR in lines with mixed fiber types

For correct insertion loss measurements with OTDR the component or line need to be measured from both sides. The average loss will be the correct loss. This can be avoided by using the same fiber at the start and at the end of the line.

Attenuation measurement with OTDR in lines with mixed fiber types

IEC SC86A Working group 1 (fibers)

• Mainly copy of ITU-T G6xx fiber documents for the singlemode fibers, but IEC 86A is the leader for the multimode fiber specifications.

IEC cable standards

Standards for patchcord cable

• The European members of IEC SC86A(cables) and IEC SC86B(optical components) have created a Joint Working Group "Cenelec JWG 86A/86BXA" to solve interface issues between cable and optical components/closures

IEC 86A compliant cable +IEC 86B compliant connector= Non functional patchcord!

Long cable lengths tested by manufacturer do not reflect the changes on the ends of the cable, nor do they reflect the real useage with short lengths in reality.

New documents IEC 60794-2-50 and IEC 60794-2-51 (draft) do contain specific cable end requirements (like minimum buffer movement, kinking during patchcord manipulation and permanent jacket shrinkage). On top of that a detailed specification with defined functional test severities is under construction finally a pigtail cable standard!

<<Update on optical fiber and cable standards(2/3)