IEC 61300-3-21:2019

IEC 61300-3-21 ®
Edition 3.0 2019-09
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Fibre optic interconnecting devices and passive components – Basic test and
measurement procedures –
Part 3-21: Examinations and measurements – Switching time

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IEC 61300-3-21 ®
Edition 3.0 2019-09
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Fibre optic interconnecting devices and passive components – Basic test and

measurement procedures –
Part 3-21: Examinations and measurements – Switching time

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.180.20 ISBN 978-2-8322-7436-1

– 2 – IEC 61300-3-21:2019 RLV © IEC 2019
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Apparatus . 7
4.1 General description . 7
4.2 Optical source (S) . 7
Excitation unit (E) .
4.3 Detector (D) . 7
4.4 Actuation energy supply (AS) . 8
4.5 Data acquisition system (DAS) . 8
4.6 Termination (T) . 8
4.7 Temporary joint (TJ) . 8
5 Procedure . 8
6 Details to be specified . 10
Bibliography . 11

Figure 1 – Measurement set-up using a 2-channel oscilloscope as DAS to measure a
single output port . 9
Figure 2 – Example of a port moving to an on-state or off-state . 9

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
FIBRE OPTIC INTERCONNECTING DEVICES AND PASSIVE
COMPONENTS – BASIC TEST AND MEASUREMENT PROCEDURES –

Part 3-21: Examinations and measurements – Switching time

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.
This redline version of the official IEC Standard allows the user to identify the changes
made to the previous edition. A vertical bar appears in the margin wherever a change
has been made. Additions are in green text, deletions are in strikethrough red text.

– 4 – IEC 61300-3-21:2019 RLV © IEC 2019
International Standard IEC 61300-3-21 has been prepared by subcommittee 86B: Fibre optic
interconnecting devices and passive components, of IEC technical committee 86: Fibre optics.
This third edition cancels and replaces the second edition published in 2014. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) changes to remove redundant overlap with IEC 60876-1;
b) clarifications to definitions and diagrams;
c) generalization of the detection apparatus beyond an oscilloscope.
The text of this International Standard is based on the following documents:
FDIS Report on voting
86B/4218/FDIS 86B/4230/RVD
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 61300 series, published under the general title, Fibre optic
interconnecting devices and passive components – Basic test and measurement procedures,
can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
FIBRE OPTIC INTERCONNECTING DEVICES AND PASSIVE
COMPONENTS – BASIC TEST AND MEASUREMENT PROCEDURES –

Part 3-21: Examinations and measurements – Switching time

1 Scope
This part of IEC 61300 is describes a method to measure the switching time and related
performance parameters of an optical a fibre optic spatial switch when the actuation energy is
applied or removed to change the state of the switch.
2 Normative references
The following documents are referred to in the text in such a way that some or all of their
content constitutes requirements of this document. For dated references, only the edition
cited applies. For undated references, the latest edition of the referenced document (including
any amendments) applies.
IEC 61300-1, Fibre optic interconnecting devices and passive components – Basic test and
measurement procedures – Part 1: General and guidance
IEC 61300-3-4, Fibre optic interconnecting devices and passive components – Basic test and
measurement procedures – Part 3-4: Examinations and measurements – Attenuation
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
3.1
latency time
elapsed time until the output power of a
specified output port reaches 10 % of its steady-state value of the output power from the time
the actuation energy is applied for a normally-on normally-off switch or is removed for a
normally-off normally-on switch
[SOURCE: IEC 60876-1:2012, 3.3.4.1, modified – “for a normally-on switch or is removed for
a normally-off switch” has been added.]
3.2
latency time
 elapsed time until the output power of a
specified output port reaches 90 % of its steady-state value of the output power from the time
the actuation energy is removed for a normally-on normally-off switch or is applied for a
normally-off normally-on switch
Note 1 to entry: For a latch type optical switch, when switching from conducting state to isolated state, actuation
energy is applied or removed.
– 6 – IEC 61300-3-21:2019 RLV © IEC 2019
[SOURCE: IEC 60876-1:2012, 3.3.4.2, modified – “for a normally-on switch or is removed for
a normally-off switch” and Note 1 to entry have been added.]
3.3
rise time
elapsed time for the output power of the specified output port to rise from 10 % of the steady-
state conducting value to 90 % of the steady-state conducting value
[SOURCE: IEC 60876-1:2012, 3.3.5, modified – “conducting” has been added.]
3.4
fall time
elapsed time for the output power of the specified output port to fall from 90 % of the steady-
state conducting value to 10 % of the steady-state conducting value
[SOURCE: IEC 60876-1:2012, 3.3.6, modified – “conducting” has been added.]
3.5
bounce time
elapsed time until the output power of a
specified output port is maintained between 90 % and 110 % of its steady-state value of the
output power from the first time the output power of a specified output port reaches 90 % of its
steady-state value of the output power
[SOURCE: IEC 60876-1:2012, 3.3.7.1]
3.6
bounce time
elapsed time until the output power of a
specified output port is maintained between 0 % and 10 % of its steady-state conducting value
of the output power from the first time the output power of a specified output port reaches
10 % of its steady-state conducting value of the output power
[SOURCE: IEC 60876-1:2012, 3.3.7.2]
3.7
switching time

t
s
t = t + t + t
s l r b
where
t is the latency time;
l
t is the rise time;
r
t is the bounce time
b
[SOURCE: IEC 60876-1:2012, 3.3.8.1]

3.8
switching time

t
s'
t = t + t + t
s l' f b'
where
t is the latency time;
l'
t is the fall time;
f
is the bounce time
t
b'
[SOURCE: IEC 60876-1:2012, 3.3.8.2]
4 Apparatus
4.1 General description
For each optical path through the switch that is to be tested, a stable optical signal from an
optical source is applied to the input port(s), and the time-dependent optical signal level at the
output port(s) is measured with respect to the time when the actuation energy specified in the
relevant specification is applied or removed.
4.2 Optical source (S)
The source output power shall be sufficiently stable over the time required to perform the
measurements. Unless otherwise specified, the optical power stability shall follow
IEC 61300-3-4. The source shall be capable of producing the spectral characteristics (both
wavelength and spectral width) defined in the relevant specification. The ouput power
required shall consider the power range of the detection system and the loss of the device
under test (DUT).
In the case that the optical source is polarized, as is usual for laser sources, then the
measurement and especially the steady-state conducting value of the output power will be
influenced by any polarization dependence in the switch, joints, or detector. Stable
environmental conditions and fibre positioning are recommended to avoid changes in the
polarization state during the measurement.
4.3 Excitation unit (E)
This is a special launch fibre or imaging system designed to achieve the required launch
conditions. The excitation unit shall follow IEC 61300-1.
4.3 Detector (D)
The detector produces an electrical signal proportional to the input optical power. The
detector shall have sufficient speed fast response time to measure the switching time and
bounce time to the accuracy specified in the relevant specification. The response time of the
detector should be less than or equal to one tenth the rise time or fall time to be measured.
The detector shall have sufficient large dynamic range to make the measurement and have
linear response of < 0,05 dB over the optical power levels expected to be encountered. The
detector shall have sufficiently high return loss to prevent impact on the measurements. The
return loss of the measurement system should be 30 dB or higher. Multiple detectors may be
used to measure multiple optical ports simultaneously.

– 8 – IEC 61300-3-21:2019 RLV © IEC 2019
4.4 Actuation energy supply (AS)
The rise time and fall time of the actuation energy supply should be less than or equal to one
tenth the rise time or fall time of the optical switch specification. The duration of the actuation
energy shall be sufficiently longer than the anticipated bounce time, for non-latch type optical
switches.
4.5 Data acquisition system (DAS)
The data acquisition system records the time-dependence of the optical power, referred to
from the time that the actuation energy is applied or removed. It shall have sufficient large
data storage capacity, bandwidth and accuracy and shall have the capability for of at least two
traces, or one trace that is synchronized by a hardware or software trigger to the actuation
energy. An oscilloscope may be used for data acquisition or the detector, and data acquisition
functions may be integrated in a data-logging optical power meter.
4.6 Termination (T)
These terminations are components or techniques to suppress reflected light from the device
under test (DUT) output ports. Impairment of the measurement by reflections at the fibre
output to the detector(s) should also be avoided. Fibre optic connectors with angled polished
contacting (APC) face are usually sufficient to achieve > 60 dB return loss. If the switch under
test has non-angled-polished connectors, they can be terminated by connecting to a cord with
a non-angled-polished connector and an angled-polished connector at the other end.
4.7 Temporary joint (TJ)
A method, device, or mechanical fixture for temporarily aligning two fibre ends into a
reproducible, low loss joint. It may can be, for example, a precision V-groove vacuum chuck,
micro-manipulator, or a fusion or mechanical splice. The attenuation and return loss stability
of the temporary joint shall be compatible with the measurement precision required.
5 Procedure
The procedure is illustrated here for a switch containing integral fibre optic pigtails without
connectors (configuration A switch, see IEC 60876-1). For switches configured with fibre optic
connectors on the pigtails or housing plugs or receptacles (configurations B or C), the
appropriate fibre cords and connectors optic patchcords or adaptors shall be used in the place
of the temporary joints. When multiple output ports are measured, each may be connected to
a detector and it should be assured that impairment from reflections is avoided.
a) Configure the switching time and bounce time measurement set-up as shown in Figure 1.
Connect the detector output to channel 1 of the data acquisition system. Additional
detectors may be used in the same way. Connect the actuation energy supply to the
optical switch and to channel 2 or the trigger input of the data acquisition system, as
shown in Figure 1.
b) When the actuation energy specified in the relevant specification is supplied or removed,
record the change in the optical power level over enough time to establish the steady-
state optical power level. Using the 10 % and 90 % power levels, determine the switching
time t , rise time t or fall time t , and bounce time t , as shown in Figure 2. Using the 0 %,
s r f b
10 % and 90 % power levels, determine the latency time t , the rise time t or fall time t , the
l r f
bounce time t , and the switching time t as shown in Figure 2. In the case in which, for any
b s
reason, the steady-state power of the isolated state is not zero, the power levels should
be normalized by subtracting from them the steady-state power of the isolated state,
before determining the switching time parameters.

Key
S optical source
TJ temporary joint
T termination
D detector
T termination
DAS data acquisition system
Figure 1 – Measurement set-up using a 2-channel oscilloscope as DAS
to measure a single output port

Key
t , t ' switching time
s s
t , t ' latency time
l l
t rise time
r
t fall time
f
t , t ' bounce time
b b
NOTE Figure 2 is valid for normally-off configuration. For a normally-on example, refer to IEC 60876-1:2014.
Figure 2 – Example of a port moving to an on-state or off-state

– 10 – IEC 61300-3-21:2019 RLV © IEC 2019
6 Details to be specified
The following details, as applicable, shall be specified in the relevant specification:
– source S: type of optical source, power, wavelength range, spectral width, power stability,
and degree of polarization;
– excitation unit E: kind of excitation unit and its specification;
– detector D: sensitivity, response frequency or response time, and polarization dependence,
linearity;
– data acquistion system DAS: DAS structure, specification, time resolution, relative signal
uncertainty and linearity;
– temporary joint: types of temporary joint, connection attenuation, and return loss;
– actuation energy supply: characteristic of applied actuation energy and rise and fall times;
– termination: type and return loss of terminations;
– performance requirement;
– deviation from standard test procedure;
– measurement uncertainty.
Bibliography
IEC 60876-1:2014, Fibre optic interconnecting devices and passive components – Fibre optic
spatial switches – Part 1: Generic specification

___________
IEC 61300-3-21 ®
Edition 3.0 2019-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Fibre optic interconnecting devices and passive components – Basic test and
measurement procedures –
Part 3-21: Examinations and measurements – Switching time

Dispositifs d’interconnexion et composants passifs fibroniques – Procedures
fondamentales d'essais et de mesures –
Partie 3-21: Examens et mesures – Temps de commutation

– 2 – IEC 61300-3-21:2019 © IEC 2019
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms and definitions . 5
4 Apparatus . 6
4.1 General description . 6
4.2 Optical source (S) . 7
4.3 Detector (D) . 7
4.4 Actuation energy supply (AS) . 7
4.5 Data acquisition system (DAS) . 7
4.6 Termination (T) . 7
4.7 Temporary joint (TJ) . 7
5 Procedure . 8
6 Details to be specified . 9
Bibliography . 10

Figure 1 – Measurement set-up using a 2-channel DAS to measure a single output port . 8
Figure 2 – Example of a port moving to an on-state or off-state . 9

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
FIBRE OPTIC INTERCONNECTING DEVICES AND PASSIVE
COMPONENTS – BASIC TEST AND MEASUREMENT PROCEDURES –

Part 3-21: Examinations and measurements – Switching time

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 61300-3-21 has been prepared by subcommittee 86B: Fibre optic
interconnecting devices and passive components, of IEC technical committee 86: Fibre optics.
This third edition cancels and replaces the second edition published in 2014. This edition
constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) changes to remove redundant overlap with IEC 60876-1;
b) clarifications to definitions and diagrams;
c) generalization of the detection apparatus beyond an oscilloscope.

– 4 – IEC 61300-3-21:2019 © IEC 2019
The text of this International Standard is based on the following documents:
FDIS Report on voting
86B/4218/FDIS 86B/4230/RVD
Full information on the voting for the approval of this International Standard can be found in
the report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 61300 series, published under the general title, Fibre optic
interconnecting devices and passive components – Basic test and measurement procedures,
can be found on the IEC website.
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://webstore.iec.ch" in the data related to
the specific document. At this date, the document will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
FIBRE OPTIC INTERCONNECTING DEVICES AND PASSIVE
COM
...