IEC 60793-1-30:2010

Optical fibres - Part 1-30: Measurement methods and test procedures - Fibre proof test

IEC 60793-1-30:2010 describes procedures for briefly applying a specified tensile load as a proof test to continuous lengths of optical fibre. The tensile load is applied for as short a time as possible, yet sufficiently long to ensure the glass experiences the proof stress, typically much less than one second. This method is applicable to types A1, A2, A3 and B optical fibres. The main change with respect to the previous edition is an improved description of the procedure.

Fibres optiques - Partie 1-30: Méthodes de mesure et procédures d'essai - Essais de sélection

IEC 60793-1-30:2010 décrit des procédures permettant d'appliquer brièvement, à titre d'essai de sélection, une force de traction déterminée à la totalité de la longueur d'une fibre optique. La force de traction est appliquée sur une durée aussi courte que possible, mais suffisamment longue toutefois pour garantir que le verre supporte les essais de contrainte, généralement quelques dixièmes de moins d'une seconde. Cette méthode est applicable aux fibres optiques de types A1, A2, A3 et B. Le but de la présente norme est d'établir des exigences uniformes applicables aux essais de sélection des caractéristiques mécaniques des fibres. Cette deuxième édition annule et remplace la première édition, publiée en 2001, dont elle constitue une révision technique. Le changement principal par rapport à l'édition précédente est une description améliorée de la procédure.
Mots clés: méthodes de mesure et les procédures d'essai s'appliquant aux fibres optiques

General Information

• Status: Published
• Publication Date: 18-May-2010
• ICS: 33.180.10 - Fibres and cables
• Technical Committee: SC 86A - Fibres and cables
• Drafting Committee: WG 1 - TC 86/SC 86A/WG 1
• Current Stage: PPUB - Publication issued
• Start Date: 19-May-2010
• Completion Date: 15-Aug-2010

Relations

• Revises: IEC 60793-1-30:2001 - Optical fibres - Part 1-30: Measurement methods and test procedures - Fibre proof test
• Effective Date: 05-Sep-2023

Standards Content (Sample)

IEC 60793-1-30 ®
Edition 2.0 2010-05
INTERNATIONAL
STANDARD
Optical fibres –
Part 1-30: Measurement methods and test procedures – Fibre proof test

All rights reserved. Unless otherwise specified, no part of this publication may be reproduced or utilized in any form
or by any means, electronic or mechanical, including photocopying and microfilm, without permission in writing from
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IEC 60793-1-30 ®
Edition 2.0 2010-05
INTERNATIONAL
STANDARD
Optical fibres –
Part 1-30: Measurement methods and test procedures – Fibre proof test

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
PRICE CODE
M
ICS 33.180.10 ISBN 978-2-88910-930-2
– 2 – 60793-1-30 © IEC:2010(E)
CONTENTS
FOREWORD.3
INTRODUCTION.5
1 Scope.6
2 Normative references .6
3 Apparatus.6
3.1 General .6
3.2 Fibre pay out .6
3.3 Proof test region.6
3.4 Fibre take-up.7
3.5 Load and unload.7
3.6 Minimum bending radii .7
3.7 Typical equipment design .7
3.7.1 Introduction .7
3.7.2 Braked capstan type.7
3.7.3 Dead weight type.8
4 Sample preparation .9
5 Procedure .9
6 Calculations – Compensation for load-sharing by coating .10
7 Results .10
7.1 Test requirement .10
7.2 Information to be provided.10
7.3 Optional information .11
8 Specification information .11
Bibliography.12

Figure 1 – Braked capstan type .8
Figure 2 – Dead weight type .8

60793-1-30 © IEC:2010(E) – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
OPTICAL FIBRES –
Part 1-30: Measurement methods and test procedures –
Fibre proof test
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60793-1-30 has been prepared by subcommittee 86A: Fibres and
cables, of IEC technical committee 86: Fibre optics.
This second edition cancels and replaces the first edition published in 2001 and constitutes a
technical revision.
The main change with respect to the previous edition is an improved description of the
procedure.
– 4 – 60793-1-30 © IEC:2010(E)
The text of this standard is based on the following documents:
CDV Report on voting
86A /1288/CDV 86A/1313/RVC
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts of the IEC 60793-1-3x series, published under the general title Optical fibres
– measurement methods and test procedures, can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
A bilingual version of this publication may be issued at a later date.

60793-1-30 © IEC:2010(E) – 5 –
INTRODUCTION
Publications in the IEC 60793-1 series concern measurement methods and test procedures as
they apply to optical fibres.
Within the same series, several different areas are grouped, but all numbers possibly not
used, as follows:
• parts 1-10 to 1-19: General
• parts 1-20 to 1-29: Measurement methods and test procedures for dimensions
• parts 1-30 to 1-39: Measurement methods and test procedures for mechanical
characteristics
• parts 1-40 to 1-49: Measurement methods and test procedures for transmission and
optical characteristics
• parts 1-50 to 1-59: Measurement methods and test procedures for environmental
characteristics
– 6 – 60793-1-30 © IEC:2010(E)
OPTICAL FIBRES –
Part 1-30: Measurement methods and test procedures –
Fibre proof test
1 Scope
This part of IEC 60793 describes procedures for briefly applying a specified tensile load as a
proof test to continuous lengths of optical fibre. The tensile load is applied for as short a time
as possible,
...

IEC 60793-1-30 ®
Edition 2.0 2010-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Optical fibres –
Part 1-30: Measurement methods and test procedures – Fibre proof test

Fibres optiques –
Partie 1-30: Méthodes de mesure et procédures d'essai – Essais de sélection
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IEC 60793-1-30 ®
Edition 2.0 2010-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Optical fibres –
Part 1-30: Measurement methods and test procedures – Fibre proof test

Fibres optiques –
Partie 1-30: Méthodes de mesure et procédures d'essai – Essais de sélection

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.180.10 ISBN 978-2-8322-5180-5

– 2 – IEC 60793-1-30:2010 © IEC 2010
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Apparatus . 6
3.1 General . 6
3.2 Fibre pay out. 6
3.3 Proof test region . 6
3.4 Fibre take-up . 7
3.5 Load and unload . 7
3.6 Minimum bending radii . 7
3.7 Typical equipment design . 7
3.7.1 Introduction . 7
3.7.2 Braked capstan type . 7
3.7.3 Dead weight type . 8
4 Sample preparation . 9
5 Procedure . 9
6 Calculations – Compensation for load-sharing by coating . 10
7 Results . 10
7.1 Test requirement . 10
7.2 Information to be provided . 11
7.3 Optional information . 11
8 Specification information . 11
Bibliography . 12

Figure 1 – Braked capstan type . 8
Figure 2 – Dead weight type . 8

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
OPTICAL FIBRES –
Part 1-30: Measurement methods and test procedures –
Fibre proof test
FOREWORD
1) The International Electrotechnical Commission (IEC) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of IEC is to promote
international co-operation on all questions concerning standardization in the electrical and electronic fields. To
this end and in addition to other activities, IEC publishes International Standards, Technical Specifications,
Technical Reports, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for Standardization (ISO) in accordance with conditions determined by
agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an international
consensus of opinion on the relevant subjects since each technical committee has representation from all
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60793-1-30 has been prepared by subcommittee 86A: Fibres and
cables, of IEC technical committee 86: Fibre optics.
This bilingual version (2017-12) corresponds to the monolingual English version, published in
2010-05.
This second edition cancels and replaces the first edition published in 2001 and constitutes a
technical revision.
The main change with respect to the previous edition is an improved description of the
procedure.
– 4 – IEC 60793-1-30:2010 © IEC 2010
The text of this standard is based on the following documents:
CDV Report on voting
86A/1288/CDV 86A/1313/RVC
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
The French version of this standard has not been voted upon.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts of the IEC 60793-1-3x series, published under the general title Optical fibres
– measurement methods and test procedures, can be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data
related to the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
INTRODUCTION
Publications in the IEC 60793-1 series concern measurement methods and test procedures as
they apply to optical fibres.
Within the same series, several different areas are grouped, but all numbers possibly not
used, as follows:
• parts 1-10 to 1-19: General
• parts 1-20 to 1-29: Measurement methods and test procedures for dimensions
• parts 1-30 to 1-39: Measurement methods and test procedures for mechanical
characteristics
• parts 1-40 to 1-49: Measurement methods and test procedures for transmission and
optical characteristics
• parts 1-50 to 1-59: Measurement methods and test procedures for environmental
characteristics
– 6 – IEC 60793-1-30:2010 © IEC 2010
OPTICAL FIBRES –
Part 1-30: Measurement methods and test procedures –
Fibre proof test
1 Scope
This part of IEC 60793 describes procedures for briefly applying a specified tensile load as a
proof test to continuous lengths of optical fibre. The tensile load is applied for as short a time
as possible, yet sufficiently long to ensure the glass experiences the proof stress, typically
much less than one second.
This method is applicable to types A1, A2, A3 and B optical fibres.
The object of this standard is to establish uniform requirements for the mechanical
characteristic fibre proof test.
2 Normative references
None.
3 Apparatus
3.1 General
There are several possible machine designs, all of which perform the basic functions required
for measuring fibre proof with the indicated general operating requirements. Care should be
used in the design so as to prevent coating damage.
Two machine types are used:
– braked capstan type;
– dead weight type.
Either machine may be used during the fibre-drawing process (on-line for coated fibre only),
or as a separate process step (off-line).
NOTE There are dynamics with on-line screening (different from off-line screening) which should be taken into
account.
3.2 Fibre pay out
Isolate the tensile load variations from the proof test region so as not to cause variations in
the proof load. Do not permit the applied proof stress to fluctuate below the value specified in
the detail specification.
3.3 Proof test region
With the exception of additional bend stress of up to 10 % of the proof stress, apply the proof
stress uniformly through the cross-sectional area of the test sample. Ensure that the load-
bearing members in this region are rigid (e. g. made of steel or aluminium). During testing, the
tension-producing mechanism(s) shall not allow the proof stress to fluctuate below the value
specified in the detail specification.

Proof testing requires that a constant stress be applied sequentially along the full length of
fibre. A break rate (failures per unit length) is statistically expected. It is carried out during
fibre manufacturing, on-line as part of the fibre drawing and coating process, or off-line as
part of the testing process.
The stress history of proof test stressing is as follows:
• stress loading from near-zero to the proof test stress during a load time;
• constant proof test stress during a dwell time;
• stress unloading from the proof test stress back down to near-zero during an unload time.
3.4 Fibre take-up
Isolate the tensile load variations from the proof test region so as not to cause variations in
the proof load. Ensure that the applied proof stress does not fluctuate below the value
specified in the detail specification.
3.5 Load and unload
The load and unload regions occur on both sides of the proof test region. Tension in the fibre
ramps up from being under constant low tension, in the pay-out region, to the full load in the
proof test region. Tension in the fibre then ramps down, from the proof test region, to a
constant low tension in the take-up region. The unload zone is the arc formed by the two
tangent points in the guide where the fibre finally leaves the loading area. (For example,
unloading across 90° of a 150 mm diameter wheel at a speed of about 12 m/s yields an
unloading time of about 10 ms.) Control the unload time to some maximum, agreed between
user and manufacturer. Accomplish ramping up and ramping down as quickly as possible.
3.6 Minimum bending radii
All radii over which the test sample passes need to be of sufficient size so that the maximum
stress and time at that stress shall not significantly degrade the strength of the sample.
3.7 Typical equipment design
3.7.1 Introduction
The following examples illustrate some typical designs. Other designs may be used, provided
the operating requirements in 3.2 to 3.6 are met.
3.7.2 Braked capstan type
A specific apparatus illustrating these requirements is shown in Figure 1. The fibre is paid out
with constant low tension. The rewinding after the proof test is also done with constant
tension. The levels of the pay-off and take-up tensions are adjustable. The proof test load is
applied to the fibre between the brake and drive capstans by creating a speed difference
between the capstans. Two belts are used to prevent slippage at the capstans. One design
can be that the high precision tension gauge measures the load on the fibre and controls the
speed difference to achieve the required proof test load. The load level and operating speed
of the equipment can be independently set. Another design can be that the difference in
speeds between the two capstans is set and controlled directly according to the desired fibre
elongation (strain), without tension measurements.
NOTE The relationship between stress and strain can be found in IEC/TR 62048 (see Bibliography).

– 8 – IEC 60793-1-30:2010 © IEC 2010

Precision tension
gauge
Brake capstan Drive capstan
Fibre
Dancer Dancer
in
proof
test
zone
IEC  891/10
Fibre pay-off region – Stage 1: Proof testing region – Stage 2: Fibre take-up region – Stage 3:
Constant pay-off Proof testing with master and braking Constant tension take-up spooling
capstan and precision tension gauge
Figure 1 – Braked capstan type
3.7.3 Dead weight type
Another specific apparatus illustrating these requirements is shown in Figure 2.
Capstan pinch belts
Take up Take up
Pay out
Pay out
capstan subassembly
capstan
subassembly
Idler
pulley
Dead weight
dancer pulley
Pay out dancer pulley
Take up dancer pulley
Load arm
Dead weight (holder)
IEC  892/10
Figure 2 – Dead weight type
This sub-assembly pays out fibre from a reel under constant low tension. The pay-out
sub-assembly has various guide rollers and pulleys, plus a motorised traversing mechanism.

The pay-out dancer pulley keeps the sample under just enough tension to run straight and
true to the proof test region, with minimum tension fluctuations. The pay-out capstan is the
start of the proof test region. This capstan is driven and synchronized with the take-up
capstan.
Two belts are required to hold the fibre sample firmly against the pay-out and take-up
capstans so that there is no slippage at the entrance to, and exit from, the proof test region.
The dancer pulley may consist of two pulleys, one behind the other on a common shaft. (The
second pulley is optional, however.) The fibre is fed first to the rear pulley, then back up to
the idler pulley, back down to the front dancer pulley and up to the take-up capstan.
The load arm is attached to both the shaft of the dead weight dancer pulley and to the dead
weight itself. The load arm is adjustable to zero balance. It is pivoted and actuates a sensor
which signals the drive capstan either to increase or decrease speed, depending on the
position of the load arm. Since both drives are controlled from a common reference, load arm
movement is negligible because the arm seeks a neutral position when the machine is at any
operating speed.
There is a thin plate at the bottom of the load arm. Weights are added to the plate to produce
the required actual proof load.
The idler pulley, which is optional, provides increased gauge length of the fibre under test. No
idler pulley is required if there is only one dancer pulley.
The take-up capstan is at the end of the proof test region. This is driven and synchronized
with the pay-out capstan so that tension fluctuations are minimized.
The take-up dancer pulley produces the desired winding tension of the fibre on the take-up
reel. (The winding tension is low in comparison to the proof test and is not part of the detail
specification requirement.)
The take-up sub-assembly takes up the fibre on a reel for final shipping or for further
processing. It has various guide rollers and pulleys to ensure even lay-down of the fibre, at
the desired tension level, so that the fibre remains on the reel without cascading.
4 Sample preparation
Use the entire length of optical fibre as the test specimen, minus short sections, typically 25 m
to 50 m at the ends (end allowance length). This allowance is required for a period of
acceleration during which the unloading time exceeds the maximum.
5 Procedure
The test specimen is fed into the machine according to the operating instructions for the
machine.
The tension load on the machine is set according to the requirements in the detail
specification.
The procedure allows easy detection of any failure in the fibre by the operator, if or when it
occurs.
The test specimen is run through the proof test machine.

– 10 – IEC 60793-1-30:2010 © IEC 2010
6 Calculations – Compensation for load-sharing by coating
Calculate the fraction, F, of the tension carried by the protective coating as follows:
2 2 2 2
E( D − D )+ E( D − D )
2 2 1 1 1 g
F=
2 2 2 2 2
[E( D − D )+ E( D − D )]+ E D
2 2 1 1 1 g g g
where
E is Young's modulus of the glass fibre in Pa;
g
E is Young's modulus of the second coating layer in Pa;
E is Young's modulus of the first coating layer in Pa;
D is the nominal diameter of the glass fibre in µm;
g
D is the nominal diameter of the second coating layer in µm;
D is the nominal diameter of the first coating layer in µm.
Use values for E and E that are consistent with the operating temperature, humidity and
2 1
strain rate. A worst case over-estimate of the coating contribution can be made by replacing
the modulus of the inner primary coating by the larger modulus of the outer primary coating.
In this way, the diameter and modulus of the inner primary coating need not be known.
Calculate the corrected proof test tension, T (N), to be applied to the coated fibre as follows:
a
(0,0008) σ
D
g p
T =
a
(1− F)
where
D is the nominal diameter of the glass fibre in µm;

g
σ is the proof stress in GPa;
p
F is the fraction of the load carried by the coating.
–3
The coefficient 0,0008 is a rounded number of π/4 × 10 .
NOTE In case of strain controlled braked capstan proof test machines, this compensation is not applicable.
7 Results
7.1 Test requirement
All fibre shall pass the proof test machine. Some surviving sections may be shorter than the
other.
If a fibre fails, evidence of failure shall be readily apparent. Fibre failure may sho
...