IEC 61300-2-43:2022

IEC 61300-2-43 ®
Edition 3.0 2022-09
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Fibre optic interconnecting devices and passive components – Basic test and
measurement procedures –
Part 2-43: Tests – Screen testing of return loss of single-mode PC optical fibre
connectors
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IEC 61300-2-43 ®
Edition 3.0 2022-09
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Fibre optic interconnecting devices and passive components – Basic test and
measurement procedures –
Part 2-43: Tests – Screen testing of return loss of single-mode PC optical fibre
connectors
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 33.180.20 ISBN 978-2-8322-5659-6

– 2 – IEC 61300-2-43:2022 RLV © IEC 2022
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms, definitions, and abbreviated terms . 5
3.1 Terms and definitions . 5
3.2 Abbreviated terms . 5
4 General description . 6
5 Apparatus . 6
5.1 General . 6
5.2 Source (S) . 6
5.3 Detector (D) . 6
5.4 Temporary joint (TJ) . 7
5.5 Termination (T) . 7
5.6 Branching device (BD) . 7
5.7 Reflection standard plug (RSP) . 7
5.8 Reflection standard cord (RSC). 7
6 Procedure . 7
6.1 Selection of the RSC . 7
6.2 Patch cord screen testing. 8
6.3 Pigtail cord screen testing . 9
7 Details to be specified and reported. 9
Annex A (informative) Screen testing of return loss of pigtails having PC fibre optic
connector . 11
Bibliography . 17

Figure 1 – Measurement set-up for open plug reflection standard . 8
Figure 2 – Measurement set-up for mated RSCs . 8
Figure 3 – Measurement set-up for patch cord screen testing . 9
Figure 4 – Measurement set-up for pigtail cord screen testing . 9
Figure A.1 – Measurement set-up of the screen test method . 12
Figure A.2 – Relationship between β and α . 14
Figure A.3 – Cumulative probability of return loss before test . 15
Figure A.4 – Cumulative probability of return loss after test . 15
Figure A.5 – Relationship between power and α . 16
Figure A.6 – Measurement set-up of the reflected powers . 16

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

Part 2-43: Tests – Screen testing of return loss of
single-mode PC optical fibre connectors

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
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Standardization (ISO) in accordance with conditions determined by agreement between the two organizations.
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This redline version of the official IEC Standard allows the user to identify the changes made to
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– 4 – IEC 61300-2-43:2022 RLV © IEC 2022
IEC 61300-2-43 has been prepared by subcommittee 86B: Fibre optic interconnecting devices
and passive components, of IEC technical committee 86: Fibre optics. It is an International
Standard.
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 change with respect to the previous
edition: addition of Clause 3 containing terms, definitions, and abbreviated terms.
The text of this International Standard is based on the following documents:
Draft Report on voting
86B/4628/FDIS 86B/4652/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/standardsdev/publications.
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 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 document indicates that it
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FIBRE OPTIC INTERCONNECTING DEVICES
AND PASSIVE COMPONENTS –
BASIC TEST AND MEASUREMENT PROCEDURES –

Part 2-43: Tests – Screen testing of return loss of
single-mode PC optical fibre connectors

1 Scope
This part of IEC 61300 aims at screening single-mode physical contact (PC) optical fibre
connectors connector plugs of an optical fibre patch cord or an optical fibre pigtail in terms of
return loss, thus ensuring minimum return loss when the connectors connector plugs, which
have been screen tested by this method are randomly mated with each other in the field. This
document is intended to apply to cylindrical ferrule connector plugs.
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 61300-3-6, Fibre optic interconnecting devices and passive components – Basic test and
measurement procedures – Part 3-6: Examinations and measurements – Return loss
3 Terms, definitions, and abbreviated terms
3.1 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminological databased for use in standardization at the following
addresses:
• ISO Online browsing platform: available at https://www.iso.org/obp
• IEC Electropedia: available at http://www.electropedia.org/
3.2 Abbreviated terms
BD branching device
D detector
DUT device under test
PC physical contact
PDL polarization dependent loss
RSC reflection standard cord
RSP reflection standard plug
S source
T termination
TJ temporary joint
– 6 – IEC 61300-2-43:2022 RLV © IEC 2022
4 General description
The domed ferrule end faces of PC connectors connector plugs (not angled) are produced by a
polishing process. This polishing process results in a thin, damaged surface layer at the fibre
end face of the connector plug. In silica fibres, the refractive index of the damaged layer is
slightly higher than that of the original fibre. This high refractive index layer generates optical
reflection. When PC connectors connector plugs are mated, return loss occurs as a result of
multiple reflections at the two damaged high index layers of the butted connectors the physically
contacting fibre end faces. This phenomenon and its effect on return loss is further explained
in IEC 61755-2-1.
This test procedure ensures that a designed minimum return loss is achieved when PC
connectors connector plugs are randomly mated. It screens patch cords or pigtails by using a
pair of reflection standard plug (RP) cords reflection standard cords (RSCs). The reflection
standard cord has a reflection standard plug (RSP) at one end. The pair of reflection standard
plugs is RSCs are selected on the condition that the return loss when the plugs are mated is
several decibels better higher than the designed minimum return loss. Patch cords which pass
this test will achieves the designed minimum return loss in over 99 % of cases when randomly
mated (see Annex A).
5 Apparatus
5.1 General
The equipment listed below used shall be chosen according to the method used to measure the
connector return loss, in accordance with IEC 61300-3-6. The reflection standard plug shall be
prepared according to the procedure given in 5.1. For the sake of simplicity, the procedure and
figures in this document reflect that of a measurement with an optical continuous wave
reflectometer (OCWR). The procedure can be adapted to any of the other measurement
methods as deemed fit.
• Sources S
• Excitation unit E
• Detector D
• Temporary joint TJ
• Terminator T
• Branching device BD
• Reflection standard cord
The reflection standard cord has a reflection standard plug (RP) at one end. The other end of
the reflection standard cord is an end or a plug whose return loss is better than the designed
minimum return loss L (in decibels).

rs
5.2 Source (S)
The source consists of an optical emitter, associated drive electronics, an excitation unit, and
a fibre connector or fibre pigtail.
5.3 Detector (D)
The detector used consists of an optical detector, the associated electronics, and a means of
connecting to an optical fibre. The optical connection may be a receptacle for an optical
connector plug, a fibre pigtail, or a bare fibre adapter.

5.4 Temporary joint (TJ)
A TJ is a joint that is made to connect the device under test (DUT) into the measurement circuit.
Examples of TJs are a connector, splice, vacuum chuck or micro-manipulator. The loss of the
TJ shall be stable, and the TJ shall have a return loss of at least 10 dB greater than the
maximum return loss to be measured.
Where a return loss greater than 50 dB is to be measured, a fusion splice is recommended in
order to guarantee the prescribed measurement uncertainty.
5.5 Termination (T)
Fibre terminations, T, shall have a high return loss. Three types of terminations are suggested:
– angled fibre ends: the value of the angle depends on the fibre type. A minimum angle of 12°
is necessary to achieve the desired high return loss;
– the application of an index matching material to the fibre end;
– attenuation in the fibre, for example, with a mandrel wrap.
Where attenuation is used as a termination, it may be applied between components.
The fibre termination shall have a return loss of at least 20 dB greater than the maximum return
loss to be measured.
Where a return loss greater than 50 dB is to be measured, the "attenuation in the fibre"
termination technique is advised in order to guarantee the prescribed measurement uncertainty.
5.6 Branching device (BD)
The BD splits light power from the source to the signal and reference ports and couples light
power from those ports into the detector.
The splitting ratio of the BD shall be stable and be insensitive to polarization. The PDL is
recommended to be less than 0,1 dB. The directivity shall be at least 10 dB higher than the
maximum return loss to be measured.
5.7 Reflection standard plug (RSP)
The RSP is a plug connector whose return loss is better than the designed minimum return loss
RL (in decibels).
rs
5.8 Reflection standard cord (RSC)
The RSC has a RSP at one end. The other end of the RSC is an end or a plug whose return
loss is better than the designed minimum return loss RL (in decibels).

rs
6 Procedure
6.1 Selection of the RSC
The reflection standard plug (RP) RSC shall be selected by the following procedure.
a) Set up an objective RSC as shown in Figure 1.

– 8 – IEC 61300-2-43:2022 RLV © IEC 2022
TJ
S E BD
RP
D 14,7 dB
IEC  2022/14
Figure 1 – Measurement set-up for open plug reflection standard
b) Set the detector to 14,7 dB as the Fresnel reflection between the air and the silica fibre core
as shown in Figure 1. The refractive index of air is 1,0, and the one of silica fibre is 1,452
for single-mode fibre on condition refractive index constant, Δ = 0,3 %, and wavelength,
λ = 1,31 µm.
NOTE Measurement accuracy uncertainty can be improved by using the actual parameters of fibres which have
been employed.
c) Connect another objective RSC as shown in Figure 2, then measure the return loss.
TJ
S E BD
T T
RP
RPRP
L + β (in decibels)
rs
D
IEC  2023/14
Figure 2 – Measurement set-up for mated RSCs
d) Take the pair of objective RSC’s as RSC’s on condition that their return loss from the mating
point is L RL + β (in decibels), where L RL is a designed minimum return loss. The

rs rs rs rs
value of β shall be set at above 2 dB.
6.2 Patch cord screen testing
Optical fibre patch cords shall be screen tested according to the following procedure.
a) Connect the device under test (DUT) (patch cord) between the RSPs as shown in Figure 3.

TJ
S E BD DU T
T T
RP RP
D
Lr (in decibels)
IEC  2024/14
Figure 3 – Measurement set-up for patch cord screen testing
b) Measure the return loss L RL (in decibels) from the two PC mating points.
r r
c) Consider the objective patch cord as a screen tested patch cord when L RL is greater than
r r
L RL .
rs rs
6.3 Pigtail cord screen testing
Optical fibre pigtails shall be screen tested according to the following procedure.
a) Connect the objective PC connector of DUT (pigtail cord) to one RSP as shown in Figure 4,
and terminate the pigtail fibre end.
TJ
S E BD DUT T T
RP
D
L + α (in decibels)
rs
IEC  2025/14
Figure 4 – Measurement set-up for pigtail cord screen testing
b) Measure the return loss L RL (in decibels) from the mating point.
r r
c) Pass the objective pigtail cord as a screen tested cord pigtail when L RL is greater than L

r r rs
RL + α (in decibels). The value of α shall be set at above 0,6 dB and at less than 5 dB.

rs
7 Details to be specified and reported
The following details, as applicable, shall be specified in the relevant specification and reported
in the test report:
– minimum return loss L RL (in decibels);
rs
rs
– condition of RSPs (the value of β in decibels);
– screening condition for pigtail cords (the value of α in decibels);
– attenuation of mating points between the reflection standard connectors RSPs and the
objective connectors connector plugs;

– 10 – IEC 61300-2-43:2022 RLV © IEC 2022
– attenuation and return loss of temporary joint;
– types of termination;
– return loss of termination;
– measurement uncertainty.
Annex A
(informative)
Screen testing of return loss of pigtails
having PC fibre optic connector
Annex A describes the theoretical background of the screen testing of return loss for pigtails.
The basic idea is the same as the screen testing of return loss of patch cords having PC fibre
optic connectors connector plugs: select a pair of reference connectors, and a measurement
pigtail is screen tested using the reference connector under a condition which is determined by
simulation, where the distribution of high refractive index layer caused by polishing process is
considered.
Two parameters β and α are introduced into this method. Parameter β is used for the selection
of a pair of reference connectors. Parameter α is used as a criterion for screen testing
measurement connectors. These two parameters β and α are carefully determined by simulation
so that return loss of mating point exceeds certain specified return loss L with high probability

rs
when the screen tested connectors are randomly connected.
The method assumes the following:
– refractive index of fibre core n is 1,452;
– refractive index of air n is 1,0.
The set-up of the measurement and test procedures will be shown first. Figure A.1 shows the
set-up with the reference patch cords 1 and 2; 1a and 2a represent reference connectors
connector plugs. Points 3a and 3b are the connectors connector plugs of the patch cord under
test and 4a is the connector plug of the pigtail under test. The connectors connector plugs
represented by 1b, 2b and 5b are angled connectors with high return loss. S is the optical
source; D is the optical detector and BD represents the optical coupler branching device. T is
a fibre termination which shall have has a high return loss; it should be made by the application
of an index matching material to the fibre end or introducing a high attenuation in the fibre, for
example, with a mandrel wrap.
– 12 – IEC 61300-2-43:2022 RLV © IEC 2022

Key
P  input power
P , P , P and P reflected power
1 2 3 8
①.④  connection conditions
and  angled connections with high return loss
non-angled PC plugs
Figure A.1 – Measurement set-up of the screen test method
The procedure of the screen test method is as follows:
a) A pair of reference plugs is selected.
– Connect the connector 1b to the connector 5b, then measure the power P (see ① in
Figure A.1).
– Connect the reference connector 2a to the reference connector 1a, then measure the
power P (see ② in Figure A.1).
The condition of selection is given by:
L < –10 log P1/P0 ≤ L + β (dB)

rs rs
RL < –10 log P /P ≤ RL + β (dB)
(A.1)
rs 1 0 rs
The measured power P can be described using P , n and n as follows:

0 8 1 2
–10 log 1/P0 = –10 log 1/P8 – 20 log (n – n ) / (n + n )
1 2 1 2
–10 log 1/P = –10 log 1/P – 20 log (n – n ) / (n + n )
(A.2)
0 8 1 2 1 2
The second term of the right side represents Fresnel reflection of air and equals 14,7 dB.
Therefore, Formula (A.1) can be rewritten as:
0 < –10 log P1/P8 + 14,7 – L ≤ β
rs
0 < –10 log P /P + 14,7 – RL ≤ β
(A.3)
1 8 rs
b) The patch cord under test is screen tested using the pair of reference connectors.
– Connect the patch cord under test 3 between the reference connectors 1a and 2a, then
measure the power P (see  Figure A.1).
The criteria for the screen test of the measurement connectors are given by:
–10 log P2/P8 + 14,7 ≥ L + α (dB)
rs
–10 log P /P + 14,7 ≥ RL + α (dB)
(A.4)
2 8 rs
c) The pigtail under test is screen tested using one of the pair reference connectors.
– Remove the reference connector 2a from reference connector 1a.
– Connect measurement connector 4a to the reference connector 1a, then measure the
(see ④ in Figure A.1).
power P
The criteria for the screen test of the measurement connectors is given by:
–10 log P3/P8 + 14,7 ≥ L + α (dB)
rs
–10 log P /P + 14,7 ≥ RL + α (dB)
(A.5)
3 8 rs
The parameters β and α are determined by simulation so that the return loss of mating point
exceeds the specified return loss L RL with high probability when the screen tested
rs
rs
connectors are randomly connected.
Figure A.2 shows the relation between β and α derived by the condition that the return loss at
the mating point exceeds a specified value L RL with a probability of 99 %. The white circles
rs
rs
represent the simulation results for pigtails. The black circles represent those for patch cords.
The lines indicate first-order regression lines. Figure A.2 indicates that the return loss of
randomly concatenated patch cords exceeds L RL (in decibels) with a probability of 99 %
rs
rs
under the condition of α ≥ 0,4β – 2,0. The parameters β and α shall be are determined according
to this condition.
– 14 – IEC 61300-2-43:2022 RLV © IEC 2022
α = 0,45β − 0,3
Cord
−2
Pigtail
α = 0,4β − 2,0
−4
−4 −2 0 2 4 6
β  (dB)
IEC  2027/14
Figure A.2 – Relationship between β and α
Figure A.3 shows the cumulative probability of return loss before screen testing. Figure A.4
shows the cumulative probability of return loss when pigtails were screen tested under the
condition of Formula (A.5) using the reference cord selected in accordance with Formula (A.1).
The parameters L RL , β and α are set at 45 dB, 5 dB and 2 dB, respectively. For pigtails, the
rs rs
probability exceeds 99 % when the return loss L RL is greater than 45 dB.

rs rs
α  (dB)
Figure A.3 – Cumulative probability of return loss before test

Figure A.4 – Cumulative probability of return loss after test
It is also important for the screen testing of pigtails that the fibre surface condition of one of the
paired reference connectors is almost equal to that of the other reference connector. Figure A.5
shows the relation of the difference of P and P and difference of α and α . P and P are the

4 5 a b 4 5
reflected power of the paired reference connectors. The power is measured in the way
described in Figure A.6 where the meaning of the symbols is the same as in Figure A.1. The
and α are individual criteria which mean that the return loss of randomly
parameters α
a b
concatenated connectors selected using the individual reference connector exceeds a specified
value L RL with a probability of 99 % under following condition:

rs rs
–10 log P2/P8 + 14,7 ≥ L + α (dB); or
a
rs
–10 log P2/P8 + 14,7 ≥ L + α (dB).
b
rs
• –10 log P /P + 14,7 ≥ RL + α (dB); or
a
2 8 rs
• –10 log P /P + 14,7 ≥ RL + α (dB).
b
2 8 rs
Figure A.5 shows that the fibre surface condition of the reference connector 1a is almost equal
to that of the reference connector 2a when the difference between the measured power P and
– 16 – IEC 61300-2-43:2022 RLV © IEC 2022
P is small. The power P and P shall should satisfy the following condition to obtain the small
5 4 5
difference between α and α within 1,0 dB:

a b
2,0 (dB) ≥ |–10 log P /P |
(A.6)
4 5
Figure A.5 – Relationship between power and α

Figure A.6 – Measurement set-up of the reflected powers

Bibliography
IEC 61300-1, Fibre optic interconnecting devices and passive components – Basic test and
measurement procedures – Part 1: General and guidance
IEC 61755-2-1, Fibre optic connector optical interfaces – Part 2-1: Optical interface standard
single mode non-angled physically contacting fibres

___________
IEC 61300-2-43 ®
Edition 3.0 2022-09
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Fibre optic interconnecting devices and passive components – Basic test and
measurement procedures –
Part 2-43: Tests – Screen testing of return loss of single-mode PC optical fibre
connectors
Dispositifs d’interconnexion et composants passifs fibroniques – Procédures
fondamentales d’essais et de mesures –
Partie 2-43: Essais – Sélection des connecteurs PC pour fibres optiques
unimodales en fonction de leur affaiblissement de réflexion

– 2 – IEC 61300-2-43:2022 © IEC 2022
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Terms, definitions, and abbreviated terms . 5
3.1 Terms and definitions . 5
3.2 Abbreviated terms . 5
4 General description . 6
5 Apparatus . 6
5.1 General . 6
5.2 Source (S) . 6
5.3 Detector (D) . 6
5.4 Temporary joint (TJ) . 6
5.5 Termination (T) . 6
5.6 Branching device (BD) . 7
5.7 Reflection standard plug (RSP) . 7
5.8 Reflection standard cord (RSC). 7
6 Procedure . 7
6.1 Selection of the RSC . 7
6.2 Patch cord screen testing. 8
6.3 Pigtail screen testing. 8
7 Details to be specified and reported. 8
Annex A (informative) Screen testing of return loss of pigtails having PC fibre optic
connector . 10
Bibliography . 16

Figure 1 – Measurement set-up for open plug reflection standard . 7
Figure 2 – Measurement set-up for mated RSCs . 8
Figure 3 – Measurement set-up for patch cord screen testing . 8
Figure 4 – Measurement set-up for pigtail screen testing . 8
Figure A.1 – Measurement set-up of the screen test method . 11
Figure A.2 – Relationship between β and α . 13
Figure A.3 – Cumulative probability of return loss before test . 13
Figure A.4 – Cumulative probability of return loss after test . 14
Figure A.5 – Relationship between power and α . 15
Figure A.6 – Measurement set-up of the reflected powers . 15

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

Part 2-43: Tests – Screen testing of return loss of
single-mode PC optical fibre connectors

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
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IEC 61300-2-43 has been prepared by subcommittee 86B: Fibre optic interconnecting devices
and passive components, of IEC technical committee 86: Fibre optics. It is an International
Standard.
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 change with respect to the previous
edition: addition of Clause 3 containing terms, definitions, and abbreviated terms.

– 4 – IEC 61300-2-43:2022 © IEC 2022
The text of this International Standard is based on the following documents:
Draft Report on voting
86B/4628/FDIS 86B/4652/RVD
Full information on the voting for its approval can be found in the report on voting indicated in
the above table.
The language used for the development of this International Standard is English.
This document was drafted in accordance with ISO/IEC Directives, Part 2, and developed in
accordance with ISO/IEC Directives, Part 1 and ISO/IEC Directives, IEC Supplement, available
at www.iec.ch/members_experts/refdocs. The main document types developed by IEC are
described in greater detail at www.iec.ch/standardsdev/publications.
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 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 COMPONENTS –
BASIC TEST AND MEASUREMENT PROCEDURES –

Part 2-43: Tests – Screen testing of return loss of
single-mode PC optical fibre connectors

1 Scope
This part of IEC 61300 aims at screening single-mode physical contact (PC) optical fibre
connector plugs of an optical fibre patch cord or an optical fibre pigtail in terms of return loss,
thus ensuring minimum return loss when the connector plugs are randomly mated with each
other in the field. This document is intended to apply to cylindrical ferrule connector plugs.
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 61300-3-6, Fibre optic interconnecting devices and passive components – Basic test and
measurement procedures – Part 3-6: Examinations and measurements – Return loss
3 Terms, definitions, and abbreviated terms
3.1 Terms and definitions
No terms and definitions are listed in this document.
ISO and IEC maintain terminological databased for use in standardization at the following
addresses:
• ISO Online browsing platform: available at https://www.iso.org/obp
• IEC Electropedia: available at http://www.electropedia.org/
3.2 Abbreviated terms
BD branching device
D detector
DUT device under test
PC physical contact
PDL polarization dependent loss
RSC reflection standard cord
RSP reflection standard plug
S source
T termination
TJ temporary joint
– 6 – IEC 61300-2-43:2022 © IEC 2022
4 General description
The domed ferrule end faces of PC connector plugs (not angled) are produced by a polishing
process. This polishing process results in a thin, damaged surface layer at the fibre end face
of the connector plug. In silica fibres, the refractive index of the damaged layer is slightly higher
than that of the original fibre. This high index layer generates optical reflection. When PC
connector plugs are mated, return loss occurs as a result of multiple reflections at the two high
index layers of the physically contacting fibre end faces. This phenomenon and its effect on
return loss is further explained in IEC 61755-2-1.
This test procedure ensures that a designed minimum return loss is achieved when PC
connector plugs are randomly mated. It screens patch cords or pigtails by using a pair of
reflection standard cords (RSCs). The reflection standard cord has a reflection standard plug
(RSP) at one end. The pair of RSCs are selected on the condition that the return loss when the
plugs are mated is several decibels higher than the designed minimum return loss. Patch cords
which pass this test achieves the designed minimum
...