SIST EN 60876-1:2002
(Main)Fibre optic spatial switches -- Part 1: Generic specification
Fibre optic spatial switches -- Part 1: Generic specification
Applies to fibre optic switches. These have the following features: -they are passive without optoelectronic elements; -they have two or more states in which power may be routed betweenports; -the ports are optical fibres or optical fibre connectors. This standard establishes uniform requirements for their optical, mechanical and environmental properties. It also establishesmeasurement and test procedures for quality assessment.
Räumliche Umschalter für Lichtwellenleiter -- Teil 1: Fachgrundspezifikation
Commutateurs spatiaux à fibres optiques -- Partie 1: Spécification générique
S'applique aux commutateurs à fibres optiques. Ces commutateurs possèdent les caracteristiques suivantes: - ils sont passifs sans aucun élément optoélectronique; - its ont au moins deux états dans lesquels la puissance optique peut passer entre ces portes; - les portes sont des fibres optiques ou des connecteurs à fibres optiques. La norme établit des exigences pour les commutateurs et les procédures d'assurance de la qualité.
Fibre optic spatial switches - Part 1: Generic specification (IEC 60876-1:2001)
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SLOVENSKI SIST EN 60876-1:2002
prva izdaja
STANDARD
september 2002
Fibre optic spatial switches - Part 1: Generic specification (IEC 60876-1:2001)
ICS 33.180.20 Referenčna številka
SIST EN 60876-1:2002(en)
© Standard je založil in izdal Slovenski inštitut za standardizacijo. Razmnoževanje ali kopiranje celote ali delov tega dokumenta ni dovoljeno
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EUROPEAN STANDARD EN 60876-1
NORME EUROPÉENNE
EUROPÄISCHE NORM October 2001
ICS 33.180.20
English version
Fibre optic spatial switches
Part 1: Generic specification
(IEC 60876-1:2001)
Commutateurs spatiaux à fibres optiques Räumliche Umschalter für
Partie 1: Spécification générique Lichtwellenleiter
(CEI 60876-1:2001) Teil 1: Fachgrundspezifikation
(IEC 60876-1:2001)
This European Standard was approved by CENELEC on 2001-10-01. CENELEC members are bound to
comply with the CEN/CENELEC Internal Regulations which stipulate the conditions for giving this European
Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on
application to the Central Secretariat or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other
language made by translation under the responsibility of a CENELEC member into its own language and
notified to the Central Secretariat has the same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Czech Republic,
Denmark, Finland, France, Germany, Greece, Iceland, Ireland, Italy, Luxembourg, Malta, Netherlands,
Norway, Portugal, Spain, Sweden, Switzerland and United Kingdom.
CENELEC
European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
Central Secretariat: rue de Stassart 35, B - 1050 Brussels
© 2001 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members.
Ref. No. EN 60876-1:2001 E
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EN 60876-1:2001 - 2 -
Foreword
The text of document 86B/1466/FDIS, future edition 3 of IEC 60876-1, prepared by SC 86B, Fibre
optic interconnecting devices and passive components, of IEC TC 86, Fibre optics, was submitted to
the IEC-CENELEC parallel vote and was approved by CENELEC as EN 60876-1 on 2001-10-01.
The following dates were fixed:
– latest date by which the EN has to be implemented
at national level by publication of an identical
national standard or by endorsement (dop) 2002-07-01
– latest date by which the national standards conflicting
with the EN have to be withdrawn (dow) 2004-10-01
Annexes designated "normative" are part of the body of the standard.
In this standard, annex ZA is normative.
Annex ZA has been added by CENELEC.
__________
Endorsement notice
The text of the International Standard IEC 60876-1:2001 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards indicated:
IEC 60068 NOTE Harmonized in the series EN 60068 (modified).
IEC 60874 NOTE Harmonized in the series EN 60874 (modified).
IEC 61753 NOTE Harmonized in the series EN 61753 (modified).
IEC 61754-2 NOTE Harmonized as EN 61754-2:1997 (not modified).
IEC 61754-4 NOTE Harmonized as EN 61754-4:1997 (not modified).
IEC 61754-13 NOTE Harmonized as EN 61754-13:1999 (not modified).
IEC 62005 NOTE Harmonized in the series EN 62005 (modified).
_________
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- 3 - EN 60876-1:2001
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
This European Standard incorporates by dated or undated reference, provisions from other
publications. These normative references are cited at the appropriate places in the text and the
publications are listed hereafter. For dated references, subsequent amendments to or revisions of any
of these publications apply to this European Standard only when incorporated in it by amendment or
revision. For undated references the latest edition of the publication referred to applies (including
amendments).
NOTE When an international publication has been modified by common modifications, indicated by (mod), the relevant
EN/HD applies.
Publication Year Title EN/HD Year
IEC 60027 Series Letter symbols to be used in electrical HD 245 Series
technology
1)
IEC 60050-731 - International Electrotechnical
Vocabulary (IEV)
Chapter 731: Optical fibre
communication
-1)
IEC 60410 Sampling plans and procedures for--
inspection by attributes
IEC 60617 Series Graphical symbols for diagrams EN 60617 Series
-1)
2)
IEC 60695-2-2 Fire hazard testing EN 60695-2-2 1994
Part 2: Test methods -- Section 2:
Needle-flame test
-1) 2)
IEC 60825-1 Safety of laser products EN 60825-1 1994
Part 1: Equipment classification, + corr. February 1994
requirements and user's guide + A11 1996
IEC 61300 Series Fibre optic interconnecting devices EN 61300 Series
and passive components - Basic test
and measurement procedures
-1)
IEC/TR3 61930 Fibre optic graphical symbology - -
IEC QC 001001 1998 Basic rules of the IEC Quality --
Assessment System for Electronic
Components (IECQ)
IEC QC 001002 Series Rules of procedure of the IEC Quality--
Assessment System for Electronic
Components (IECQ)
1)
undated reference.
2)
valid edition at date of issue.
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EN 60876-1:2001 - 4 -
Publication Year Title EN/HD Year
-1)
IEC Guide 102 Electronic components - Specification--
structures for quality assessment
(Qualification approval and capability
approval)
-1)
ISO 129 Technical drawings - Dimensioning ---
General principles, definitions,
methods of execution and special
indications
-1) 2)
ISO 286-1 ISO system of limits and fits EN 20286-1 1993
Part 1: Bases of tolerances, deviations
and fit
3)
ISO 1101 Geometrical Product Specification--
(GPS) - Geometrical tolerancing -
Generalities, definitions, symbols,
indications on drawings
ISO 8601 1988 Data elements and interchange EN 28601 1992
formats - Information interchange -
Representation of dates and times
3)
To be published.
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NORME
CEI
INTERNATIONALE IEC
60876-1
INTERNATIONAL
QC 820000
STANDARD
Troisième édition
Third edition
2001-04
Commutateurs spatiaux à fibres optiques –
Partie 1:
Spécification générique
Fibre optic spatial switches –
Part 1:
Generic specification
© IEC 2001 Droits de reproduction réservés ⎯ Copyright - all rights reserved
Aucune partie de cette publication ne peut être reproduite ni No part of this publication may be reproduced or utilized in
utilisée sous quelque forme que ce soit et par aucun procédé, any form or by any means, electronic or mechanical,
électronique ou mécanique, y compris la photocopie et les including photocopying and microfilm, without permission in
microfilms, sans l'accord écrit de l'éditeur. writing from the publisher.
International Electrotechnical Commission 3, rue de Varembé Geneva, Switzerland
Telefax: +41 22 919 0300 e-mail: inmail@iec.ch IEC web site http://www.iec.ch
CODE PRIX
Commission Electrotechnique Internationale
V
PRICE CODE
International Electrotechnical Commission
Pour prix, voir catalogue en vigueur
For price, see current catalogue
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60876-1 © IEC:2001 – 3 –
CONTENTS
Page
FOREWORD . 5
INTRODUCTION .9
Clause
1 General. 11
1.1 Scope . 11
1.2 Normative references. 11
1.3 Definitions. 13
2 Requirements. 21
2.1 Classification . 21
2.2 Documentation. 35
2.3 Standardization system . 41
2.4 Design and construction. 51
2.5 Quality . 51
2.6 Performance . 51
2.7 Identification and marking . 51
2.8 Packaging. 53
2.9 Storage conditions . 53
2.10 Safety . 53
3 Quality assessment procedures. 55
3.1 Primary stage of manufacture. 55
3.2 Structurally similar components. 55
3.3 Qualification approval procedures . 55
3.4 Quality conformance inspection. 59
3.5 Certified records of released lots. 61
3.6 Delayed deliveries. 63
3.7 Delivery release before completion of group B tests. 63
3.8 Alternative test methods. 63
3.9 Unchecked parameters . 63
Bibliography . 65
Figure 1 – Standards .49
Table 1 – Example of a typical switch classification. 21
Table 2 – Transfer matrix of a four-port switch without crossover . 27
Table 3 – Transfer matrix of a four-port crossover switch . 29
Table 4 – The IEC specification structure. 37
Table 5 – Standards interlink matrix. 49
Table 6 – Quality assurance options . 49
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60876-1 © IEC:2001 – 5 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
––––––––––––
FIBRE OPTIC SPATIAL SWITCHES –
Part 1: Generic specification
FOREWORD
1) The IEC (International Electrotechnical Commission) is a worldwide organization for standardization comprising
all national electrotechnical committees (IEC National Committees). The object of the 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, the IEC publishes International Standards. 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. The 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 the 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 National Committees.
3) The documents produced have the form of recommendations for international use and are published in the form
of standards, technical specifications, technical reports or guides and they are accepted by the National
Committees in that sense.
4) In order to promote international unification, IEC National Committees undertake to apply IEC International
Standards transparently to the maximum extent possible in their national and regional standards. Any
divergence between the IEC Standard and the corresponding national or regional standard shall be clearly
indicated in the latter.
5) The IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with one of its standards.
6) Attention is drawn to the possibility that some of the elements of this International Standard may be the subject
of patent rights. The IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60876-1 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 1994, and constitutes a
technical revision.
The text of this standard is based on the following documents:
FDIS Report on voting
86B/1466/FDIS 86B/1534/RVD
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 3.
The QC number that appears on the front cover of this publication is the specification number
in the IEC Quality Assessment System for Electronic Components (IECQ).
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60876-1 © IEC:2001 – 7 –
The committee has decided that the contents of this publication will remain unchanged until
2008. At this date, the publication will be
reconfirmed;
withdrawn;
replaced by a revised edition, or
amended.
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60876-1 © IEC:2001 – 9 –
INTRODUCTION
This part of IEC 60876 is divided into three clauses.
Clause 1, "General", contains the scope, the normative references and the definitions which
pertain to this generic specification.
Clause 2, "Requirements", contains all of the requirements to be met by switches covered by
this standard. These include requirements for classification, the IEC specification system,
documentation, materials, workmanship, quality, performance, identification, and packaging.
Clause 3, "Quality assessment procedures", contains all of the procedures to be followed for
proper quality assessment of products as covered by this standard.
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60876-1 © IEC:2001 – 11 –
FIBRE OPTIC SPATIAL SWITCHES –
Part 1: Generic specification
1 General
1.1 Scope
This part of IEC 60876 applies to fibre optic switches possessing all of the following general
features:
– they are passive in that they contain no optoelectronic or other transducing elements;
– they have one or more ports for the transmission of optical power and two or more states in
which power may be routed or blocked between these ports;
– the ports are optical fibres or optical fibre connectors.
This standard establishes uniform requirements for:
– fibre optic switch requirements;
– quality assessment procedures.
1.2 Normative references
The following normative documents contain provisions which, through reference in this text,
constitute provisions of this part of IEC 60876. For dated references, subsequent amendments
to, or revisions of, any of these publications do not apply. However, parties to agreements
based on this part of IEC 60876 are encouraged to investigate the possibility of applying the
most recent editions of the normative documents indicated below. For undated references, the
latest edition of the normative document referred to applies. Members of IEC and ISO maintain
registers of currently valid International Standards.
IEC 60027 (all parts), Letter symbols to be used in electrical technology
IEC 60050(731), International Electrotechnical Vocabulary (IEV) – Chapter 731: Optical fibre
communication
IEC 60410, Sampling plans and procedures for inspection by attributes
IEC 60617 (all parts), Graphical symbols for diagrams
IEC 60695-2-2, Fire hazard testing – Part 2: Test methods – Section 2: Needle-flame test
IEC 60825-1, Safety of laser products – Part 1: Equipment classification, requirements and
user’s guide
IEC 61300 (all parts), Fibre optic interconnecting devices and passive components – Basic test
and measurement procedures
IEC 61930, Fibre optic graphical symbology
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60876-1 © IEC:2001 – 13 –
IEC QC 001001:1998, IEC Quality Assessment System for Electronic Components (IECQ) –
Basic Rules
IEC QC 001002 (all parts), IEC Quality Assessment System for Electronic Components (IECQ)
– Rules of Procedure
IEC Guide 102, Electronic components – Specification structures for quality assessment
(Qualification approval and capability approval)
ISO 129, Technical drawings – Dimensioning – General principles, definitions, methods of
execution and special indications
ISO 286-1, ISO system of limits and fits – Part 1: Bases of tolerances, deviations and fits
ISO 1101, Geometrical Product Specifications (GPS) – Geometrical tolerancing – Tolerances of
1)
form, orientation, location and run-out
ISO 8601:1988, Data elements and interchange formats – Information interchange –
Representation of dates and times
1.3 Definitions
For the purpose of this part of IEC 60876, the definitions given in IEC 60050(731) apply,
together with the following definitions.
1.3.1
optical switch
passive component possessing one or more ports which selectively transmits, redirects or
blocks optical power in an optical fibre transmission line
1.3.2
port
optical fibre or optical fibre connector attached to a passive component for the entry and/or exit
of optical power
1.3.3
switch state
particular optical configuration of a switch, whereby optical power is transmitted or blocked
between specific ports in a predetermined manner
1.3.4
actuation mechanism
physical means (mechanical, electrical, acoustic, optical, etc.) by which a switch is designed to
change between states
1.3.5
actuation energy
input energy required to place a switch in a specific state
–––––––––––––
1)
To be published.
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60876-1 © IEC:2001 – 15 –
1.3.6
transfer matrix
optical properties of a fibre optic switch can be defined in a n × n matrix of coefficients (n is the
number of ports)
NOTE The T matrix represents the on-state paths (worst-case transmission) and the T° matrix represents the off-
state paths (worst-case isolation).
1.3.7
transfer coefficient
element t or t° of the transfer matrix
ij ij
NOTE Each coefficient t is the worst-case (minimum) fraction of power transferred from port i to port j for any
ij
state with path ij switched on. Each coefficient t° is the worst-case (maximum) fraction of power transferred from
ij
port i to port j for any state with path ij switched off.
1.3.8
logarithmic transfer matrix
in general, the logarithmic transfer matrix is as follows:
a = –10 log t
ij ij
where
a is the optical power reduction in decibels out of port j with unit power into port i, i.e.
ij
t is the transfer matrix coefficient.
ij
Similarly, for the off state, a° = 10 log t°
ij ij
1.3.9
attenuation
element a (where i ≠ j) of the logarithmic transfer matrix. It is the reduction in optical power
ij
between an input and output port of a passive component expressed in decibels and is defined
as follows:
a = –10 log (P /P )
ij j i
where
P is the optical power launched into the input port, and
i
P is the optical power received from the output port. The insertion loss values depend on the
j
state of the switch
1.3.10
return loss – reflection loss
element a (where i = j) of the logarithmic transfer matrix. It is the fraction of input power that is
ij
returned from the input port of a passive component and is defined as follows:
RL = –10 log (PR /P )
i
i i
where
P is the optical power launched into the input port, and
i
P the optical power received back from the same port.
j
The return loss values depend on the state of the switch
1.3.11
operating wavelength
nominal wavelength λ, at which a passive component is designed to operate with the specified
performance
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60876-1 © IEC:2001 – 17 –
1.3.12
operating wavelength range (bandpass)
specified range of wavelengths from λ to λ around a nominal operating wavelength λ ,
i min i max i
within which a passive component is designed to operate with the specified performance
1.3.13
conducting ports
two ports between which the attenuation is nominally zero for a passive component
1.3.14
isolated ports
two ports between which the attenuation is nominally infinite for a passive component
1.3.15
crosstalk
ratio of the optical power that goes out from a given output port to an optical power that goes
out from another output port, nominally isolated from the previous one, when all other ports are
terminated
EXAMPLE: Typical 1 × 2 switch
Switch
P
1
P
in
P
2
IEC 397/01
When the switch is connected to port 1, crosstalk is defined as follows:
P
2
FC = −10 log
12
P
1
where
P is the optical power that goes out from the output port 1, and
1
P is the optical power that goes out from the output port 2 (nominally isolated from port 1).
2
When the switch is connected to port 2, crosstalk is defined as follows:
P
1
FC = −10 log
21
P
2
where
P is the optical power that goes out from the output port 2, and
2
P is the optical power that goes out from the output port 1 (nominally isolated from port 2)
1
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60876-1 © IEC:2001 – 19 –
1.3.16
latching switch
switch that maintains its last state and specified performance level when the actuation energy
which initiated the change is removed
1.3.17
non-latching switch
switch that reverts to a home state or undefined state when the actuation energy which initiated
a change is removed
1.3.18
switching time
elapsed time it takes the switch to turn path ij on or off from a particular initial state, measured
from the time the actuation energy is applied or removed
Actuation energy supply
Steady state
Output port power
Power
90 % of steady state
10 % of steady state
t t t
r b f
Time
Switching time: t , t
r f
Bounce time: t
IEC 398/01
b
1.3.19
bounce time
elapsed time for the insertion loss between two specified ports of a switch to reach and remain
within 0,5 dB of its steady-state value from when it initially reaches within 0,5 dB of the steady-
state value
1.3.20
switching time matrix
matrix of coefficients in which each coefficient S is the longest switching time to turn path ij on
ij
or off from any initial state
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60876-1 © IEC:2001 – 21 –
1.3.21
blocking
blocking and various degrees of non-blocking operation functionality are encompassed by this
specification
NOTE “Blocking” refers to the inability to establish a connection from a free input port to a free output port due to
the existence of some other established connection.
“Strict-sense non-blocking” refers to a switch matrix in which it is always possible to establish a connection between
any free input port and any free output port irrespective of previously established connections.
“Wide-sense non-blocking” refers to a matrix in which it is always possible to establish a desired connection
provided that some systematic procedure is followed in setting up connections. Some multistage switching
architectures fall into this category.
“Rearrangeably non-blocking” refers to a switch matrix in which any free input port can be connected to any free
output port provided that other established connections are unconnected and then reconnected as part of making
the new connection.
2 Requirements
The requirements for switches covered by this clause are intended to aid in classifying this
device.
2.1 Classification
Fibre optic spatial switches shall be classified as follows:
– type;
–style;
– variant;
– interface standard (when applicable);
– environmental category;
– assessment level;
– normative reference extensions.
The following table is an example of a switch classification.
Table 1 – Example of a typical switch classification
Type: 2 × 2 electrically actuated switch
Style: – Configuration B
– IEC type A1 a fibre
– F-SMA connector
Variants: Means of mounting
Environmental category: .
Assessment level: A
Normative reference extensions: .
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60876-1 © IEC:2001 – 23 –
2.1.1 Type
Switches are divided into types by their actuating mechanism and topology (optical switching
function).
There are an essentially infinite number of possible topologies. Each topology is illustrated by a
schematic diagram and defined by a unique transfer matrix.
The following device topologies include only those which are in common use within industry at
present. The schematic diagrams which follow do not necessarily correspond to the physical
layout of the switch and its ports.
NOTE The following examples apply to unidirectional switches only, where t = t . For bi-directional switches,
ij ji
t = t in each transfer matrix below.
ij ji
2.1.1.1 Single-pole, single-throw switch
Off
12
On
IEC 399/01
This switch has one input and one output port. The transfer matrix describing the device is as
follows:
Ideally, t is 1 and the other coefficients are 0 when the switch is on. When the switch is off,
12
all coefficients are 0.
2.1.1.2 Single-pole, N-throw switch
2
1
3
.
.
.
.
N + 1
IEC 400/01
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60876-1 © IEC:2001 – 25 –
This switch has one input port and N output ports. The transfer matrix describing the device is
as follows:
Ideally, in the first position of the switch, t is 1 and the other coefficients are 0. In the generic
12
i-th position of the switch, the t transfer coefficient is 1 and the others are 0.
1 i+1
2.1.1.3 N-port matrix switch
. . . .
12 3 N
IEC 401/01
This switch has N ports. The transfer matrix describing the device is as follows:
A 2 × 2 matrix switch is a particular case with two input and two output ports.
In one type, it is possible to have four positions with the transfer coefficients t and t always
14 23
zero while t and t have the values indicated in table 2.
13 24
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60876-1 © IEC:2001 – 27 –
Table 2 – Transfer matrix of a four-port switch without crossover
Transfer coefficient State
12 34
t 10 10
13
t 11 00
24
13 State 1
2 4 State 4
13 State 2
4 State 3
2
IEC 402/01
In another type, a four-port crossover switch or by-pass switch is described. This switch has
two input and two output ports. The transfer coefficients are indicated in table 3.
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60876-1 © IEC:2001 – 29 –
Table 3 – Transfer matrix of a four-port crossover switch
Transfer coefficient State
12
t 10
13
t 10
24
t 01
14
t 01
23
13 State 1
2 4 State 2
IEC 403/01
2.1.2 Style
Switches may be classified into styles based upon fibre type, connector type, cable type,
housing shape and dimensions and configuration.
Configuration
The configuration of the switch ports is classified as follows.
Configuration A
A device containing integral fibre optic pigtails without connectors.
Switch
IEC 404/01
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60876-1 © IEC:2001 – 31 –
Configuration B
A device containing integral fibre optic pigtails, with a connector on each pigtail.
Switch
IEC 405/01
Configuration C
A device containing a fibre optic connector as an integral part of the device housing.
Switch
IEC 406/01
Configuration D
A device containing some combination of the interfacing features of the preceding
configurations.
2.1.3 Variant
The switch variant identifies those features which encompass structurally similar components
(see 3.2).
Examples of features which define a variant include, but are not limited to the following:
– orientation of ports on housing;
– means for mounting.
2.1.4 Interface standard
Where a particular switch variant possesses an integral
...
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