IEC TR 62959:2021

Optical fibre cables - Shrinkage effects on cable and cable element end termination - Guidance

IEC TR 62959:2021 which is a Technical Report, provides information on cable shrinkage characterisation of optical fibre cables that consist of standard glass optical fibres for telecommunication application. The characterisation is directed to the effects of cable shrinkage or cable element shrinkage on the termination of cables. Shrinkage can or cannot be a concern depending on the method of termination. Examples of different cable termination cases are included and described. Tests for the evaluation of cable shrinkage are recommended that can be used as indicators, and shrinkage classification by several grades are given.

General Information

• Status: Published
• Publication Date: 16-Feb-2021
• ICS: 33.180.10 - Fibres and cables
• Technical Committee: SC 86A - Fibres and cables
• Current Stage: PPUB - Publication issued
• Start Date: 03-Mar-2021
• Completion Date: 17-Feb-2021

Standards Content (Sample)

IEC TR 62959 ®
Edition 1.0 2021-02
TECHNICAL
REPORT
colour
inside
Optical fibre cables – Shrinkage effects on cable and cable element end
termination – Guidance
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IEC TR 62959 ®
Edition 1.0 2021-02
TECHNICAL
REPORT
colour
inside
Optical fibre cables – Shrinkage effects on cable and cable element end

termination – Guidance
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.180.10 ISBN 978-2-8322-9434-5

– 2 – IEC TR 62959:2021  IEC 2021
CONTENTS
FOREWORD . 7
INTRODUCTION . 9
1 Scope . 10
2 Normative references . 10
3 Terms and definitions . 10
4 Abbreviated terms . 11
5 Characteristics of optical fibre cables . 11
5.1 General . 11
5.2 Cable materials . 11
5.2.1 Plastic materials . 11
5.2.2 Reversible thermal expansion and contraction . 11
5.2.3 Irreversible thermal contraction (shrinkage) . 12
5.2.4 Forces between cable elements caused by thermal changes . 13
5.3 Cable design . 13
5.4 Basic cable types . 14
5.5 Cable performance . 15
5.5.1 General . 15
5.5.2 Optical performance during temperature changes . 15
5.5.3 Cable shrinkage characteristic . 16
5.5.4 Cable shrinkage during connector termination process . 16
6 Test methods for cable shrinkage . 17
6.1 General . 17
6.2 Conditions before shrinkage testing . 17
6.3 Test method F11 . 17
6.4 Test method F17 . 18
7 Conclusions of the cable shrinkage study . 19
7.1 General . 19
7.2 Conclusion for simplex cables . 19
7.3 Conclusion for loose tube cables . 20
8 Termination cases of optical fibre cables . 20
8.1 General . 20
8.2 Different termination cases . 20
9 Recommended tests for evaluation of shrinkage effects . 21
9.1 General . 21
9.2 Limitation of tests for determination of shrinkage effects . 22
9.3 Cables terminated with connectors. 22
9.3.1 Performance indicator tests . 22
9.3.2 Cable shrinkage . 22
9.3.3 Cable thermal expansion and contraction . 22
9.3.4 Cable element forces . 22
9.4 Cables terminated with hardened connectors . 22
9.4.1 Performance indicator tests . 22
9.4.2 Cable shrinkage (fibre protrusion) . 23
9.5 Cables fixed into a module and fibres terminated with connectors . 23
9.5.1 Performance indicator tests . 23
9.5.2 Cable shrinkage (fibre protrusion) . 23

9.6 Cables fixed into a divider and fan-out cables terminated with connectors . 23
9.6.1 Performance indicator tests . 23
9.6.2 General . 24
9.6.3 Shrinkage (fibre protrusion) . 24
9.6.4 Shrinkage of fan-out cable . 24
9.7 Cables fixed into a protective housing and terminated with splices . 25
9.7.1 Performance indicator tests . 25
9.7.2 Cable shrinkage (fibre protrusion) . 25
9.7.3 Sheath shrinkage . 25
9.8 Cables fixed into a protective housing and terminated with connectors . 25
9.8.1 Performance indicator tests . 25
9.8.2 Cable shrinkage . 25
10 Recommended test parameters for shrinkage testing and shrinkage grades . 26
10.1 General . 26
10.2 Recommended test parameters for shrinkage testing . 26
10.3 Shrinkage grades for Method F11A . 27
10.4 Recommended shrinkage limit for Method F11B. 27
10.5 Fibre protrusion grades for Method F17 . 27
Annex A (informative) Test results of the cable shrinkage study . 29
A.1 General . 29
A.2 Shrinkage test results of simplex cables . 29
A.2.1 Simplex cable types for shrinkage tests . 29
A.2.2 Shrinkage test with different aging methods and duration . 29
A.2.3 Shrinkage test with various numbers of temperature cycles . 33
A.2.4 Shrinkage test with different sample lengths . 34
A.2.5 Shrinkage test versus optical performance of two different simplex
cables . 34
A.2.6 Shrinkage test versus optical performance of different versions of a
simplex cable . 36
A.2.7 Change in length during and after climatic exposure . 36
A.3 Shrinkage test results for loose tube cables . 37
A.3.1 Loose tube cable types for shrinkage tests . 37
A.3.2 Shrinkage test (method F11 modified) of four loose tube cable types . 37
A.3.3 Shrinkage test (method F17) of four loose tube cable types . 39
A.3.4 Shrinkage test of nine unitube cable types . 43
Annex B (informative) Test method for change in length during climatic exposure . 45
B.1 General . 45
B.2 Cable samples . 45
B.3 Apparatus for determination of the change in length . 45
B.4 Procedure for determination of the change in length . 46
B.5 Test results for the change in length . 46
B.6 Procedure for determination of the change in attenuation. 47
B.7 Test results for the change in attenuation . 47
B.8 Comparison of change in length with change in attenuation . 50
B.9 Conclusion . 51
Annex C (informative) Shrinkage testing template . 52
Annex D (informative)  Recommended tests for performance evaluation of cables to
be terminated with connectors . 53
D.1 General . 53

– 4 – IEC TR 62959:2021  IEC 2021
D.2 Connector types and design . 53
D.3 Simplex and duplex cable types . 55
D.4 Termination of a cable to a connector . 56
D.5 Overview of recommended cable tests . 57
D.6 Main performance of a terminated cable . 57
D.7 Guidance for change of temperature test methods .
...