IEC 61300-3-4:2012

IEC 61300-3-4 ®
Edition 3.0 2012-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Fibre optic interconnecting devices and passive components – Basic test and
measurement procedures –
Part 3-4: Examinations and measurements – Attenuation

Dispositifs d'interconnexion et composants passifs à fibres optiques –
Méthodes fondamentales d’essais et de mesures –
Partie 3-4: Examens et mesures – Affaiblissement

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IEC 61300-3-4 ®
Edition 3.0 2012-12
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Fibre optic interconnecting devices and passive components – Basic test and

measurement procedures –
Part 3-4: Examinations and measurements – Attenuation

Dispositifs d'interconnexion et composants passifs à fibres optiques –

Méthodes fondamentales d’essais et de mesures –

Partie 3-4: Examens et mesures – Affaiblissement

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX Q
ICS 33.180.20 ISBN 978-2-83220-491-7

– 2 – 61300-3-4 © IEC:2012
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 General description . 5
3.1 General . 5
3.2 Precautions . 6
4 Apparatus . 6
4.1 Launch conditions and source (S) . 6
4.2 Optical power meter (D) . 7
4.3 Temporary joint (TJ) . 7
4.4 Fibre . 7
4.5 Reference plugs (RP) . 8
4.6 Reference adaptors (RA) . 8
5 Procedure. 8
5.1 Pre-conditioning . 8
5.2 Visual inspection . 8
5.3 DUT configurations and test methods . 8
5.4 Attenuation measurements with a power meter . 9
5.4.1 General . 9
5.4.2 Cutback method . 9
5.4.3 Substitution method . 10
5.4.4 Insertion method (A) . 11
5.4.5 Insertion method (B) with direct coupling to power meter . 11
5.4.6 Insertion method (C) with additional test patchcord . 12
5.5 Attenuation measurements with an OTDR . 13
5.5.1 Measurement description . 13
5.5.2 Bidirectional measurement . 14
5.5.3 Measurement method . 15
5.5.4 Evaluation procedure . 15
6 Details to be specified . 16
Bibliography . 17

Figure 1 – Cutback method – Type 1, Type 2 and Type 3 DUTs . 10
Figure 2 – Substitution method – Type 4 DUT . 10
Figure 3 – Insertion method (C1) – Type 2 DUT . 11
Figure 4 – Insertion method (C2) – Type 5 and Type 6 DUT . 12
Figure 5 – Insertion method (C3) – Type 4, Type 5, Type 7 and Type 8 DUT . 13
Figure 6 – Method 1 – One launch section . 14
Figure 7 – Method 2 – Two launch sections . 14
Figure 8 – Non-reflective event . 15
Figure 9 – Reflective event . 16

Table 1 – Preferred source conditions . 6
Table 2 – Preferred power meter parameters . 7
Table 3 – DUT configurations . 8

61300-3-4 © IEC:2012 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
FIBRE OPTIC INTERCONNECTING DEVICES
AND PASSIVE COMPONENTS –
BASIC TEST AND MEASUREMENT PROCEDURES –

Part 3-4: Examinations and measurements – Attenuation

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
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6) All users should ensure that they have the latest edition of this publication.
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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 61300-3-4 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 2001. It constitutes a
technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) revision of source conditions, launch conditions and power meter parameters;
b) addition of safety recommendations;
c) removal of launch condition details for multimode fibres, now referenced in 61300-1.

– 4 – 61300-3-4 © IEC:2012
The text of this standard is based on the following documents:
FDIS Report on voting
86B/3494/FDIS 86B/3541/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 2.
A list of all the parts in IEC 61300 series, published under the general title, Fibre optic
interconnecting and passive components – Basic test and measurement 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.
61300-3-4 © IEC:2012 – 5 –
FIBRE OPTIC INTERCONNECTING DEVICES
AND PASSIVE COMPONENTS –
BASIC TEST AND MEASUREMENT PROCEDURES –

Part 3-4: Examinations and measurements – Attenuation

1 Scope
This part of IEC 61300 describes the various methods available to measure the attenuation of
optical components. It is not, however, applicable to dense wavelength division multiplexing
(DWDM) components, for which IEC 61300-3-29 should be used.
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60793-2, Optical fibres – Part 2: Product specifications – General
IEC 60825-1, Safety of laser products – Part 1: Equipment classification and requirements
IEC 61300-1:2011, Fibre optic interconnecting devices and passive components – Basic test
and measurement procedures – Part 1: General and guidance
IEC 61300-3-1, Fibre optic interconnecting devices and passive components – Basic test and
measurement procedures – Part 3-1: Examinations and measurements – Visual examination
IEC 61300-3-2, Fibre optic interconnecting devices and passive components – Basic test and
measurement procedures – Part 3-2: Examinations and measurements – Polarization
dependent loss in a single-mode fibre optic device
IEC/TR 62316, Guidance for the interpretation of OTDR backscattering traces
3 General description
3.1 General
Attenuation is intended to give a value for the decrease of useful power, expressed in
decibels, resulting from the insertion of a device under test (DUT), within a length of optical
fibre cable. The term insertion loss is sometimes used in place of attenuation.
The DUT may have more than two optical ports. However, since an attenuation measurement
is made across only two ports, the DUTs in this standard shall be described as having two
ports. Eight different DUT configurations are described. The differences between these
configurations are primarily in the terminations of the optical ports. Terminations may consist
of bare fibre, a connector plug, or a receptacle.
The reference method for measuring attenuation is with an optical power meter. Optical time
domain reflectometry (OTDR) measurements are presented as an alternative method. Three
variations in the measurement of attenuation with a power meter are presented. The reference

– 6 – 61300-3-4 © IEC:2012
and alternative methods to be used for each DUT configuration are defined in Table 3.
Different test configurations and methods will result in different accuracies of the attenuation
being measured. In cases of dispute, the reference test method should be used.
3.2 Precautions
The power in the fibre shall not be at a level high enough to generate non-linear scattering
effects.
The position of the fibres in the test should be fixed between the measurement of P and P to
0 1
avoid changes in attenuation due to bending loss.
In multimode measurements, a change in modal distribution in the measurement system due
to fibre disturbance, will affect the attenuation measurement.
Components with polarization dependent loss will show different attenuation depending on the
input state of polarization from the source. If the component PDL can exceed the acceptable
uncertainty in the attenuation measurement, then either an unpolarized or polarization
scrambled source can be used to measure the polarization averaged attenuation or the
methods of IEC 61300-3-2 should be used to measure PDL and attenuation together.
The safety recommendations in IEC 60825-1, Safety of laser products, should be followed.
4 Apparatus
4.1 Launch conditions and source (S)
Table 1 – Preferred source conditions
No. Type Central wavelength Spectral width Source type
nm nm
S1 Multi-mode Monochromator or LED
660 ± 30 ≥30
S2 Multi-mode 780 ± 30 ≥30 Monochromator or LED
S3 Multi-mode 850 ± 30 ≥30 Monochromator or LED
S4 Multi-mode Monochromator or LED
1 300 ± 30 ≥30
S5 Single-mode To be reported Laser diode monochromator or LED
1 310 ± 30
S6 Single-mode 1 550 ± 30 To be reported Laser diode monochromator or LED
S7 Single-mode To be reported Laser diode monochromator or LED
1 625 ± 30
NOTE 1 It is recognized that some components, e.g. for CWDM, may require the use of other source types such
as tunable lasers. It is therefore recommended in these cases that the preferred source characteristics are
specified on the basis of the component to be measured.
NOTE 2 Central wavelength and spectral width are defined in IEC 61280-1-3.

The launch condition shall be specified in accordance with Clause 9 of IEC 61300-1:2011.
The source unit consists of an optical emitter, the associated drive electronics and fibre pigtail
(if any). Preferred source conditions are given in Table 1. The stability of the single-mode
fibre source at 23 °C shall be ±0,01 dB over the duration of the measurement. The stability of
the multimode fibre source at 23 °C shall be ± 0,05 dB over the duration of the measurement.
The source output power shall be ≥ 20 dB above the minimum measurable power level.

61300-3-4 © IEC:2012 – 7 –
4.2 Optical power meter (D)
The power meter unit consists of an optical detector, the mechanism for connecting to it and
associated detection electronics. The connection to the detector will either be with an adaptor
that accepts a bare fibre or a connector plug of the appropriate design.
The measurement system shall be stable within specified limits over the period of time
required to measure P and P . For measurements where the connection to the detector must
0 1
be broken between the measurement of P and P , the measurement repeatability shall be
0 1
within 0,02 dB. A detector with a large sensitive area may be used to achieve this.
The precise characteristics of the detector shall be compatible with the measurement
requirements. The dynamic range of the power meter shall be capable of measuring the
power level exiting from the DUT at the wavelength being measured.
The preferred power meter parameters are given below in Table 2. The power meter shall be
calibrated for the operational wavelength and power level. The power meter stability should
be ≤ 0,01 dB over the measurement time and operational temperature range. The stability and
validity of dark current corrections from zeroing calibration can influence this.
Table 2 – Preferred power meter parameters
Number Type Maximum nonlinearity Relative uncertainty
dB dB
D1 Multi-mode
± 0,05
≤ 0,05
(-60 dBm < input power < –5 dBm)
D2 Single-mode
± 0,01
(attenuation < 10 dB)
≤ 0,02
± 0,05
(10 dB < attenuation < 60 dB)
NOTE 1 In order to ensure that all light exiting the fibre is detected by the power meter, the sensitive area of the
detector and the relative position between it and the fibre should be compatible with the numerical aperture of the
fibre.
NOTE 2 Common sources of relative uncertainty are polarization dependence and interference with reflections
from the power meter and fibre connector surfaces. The sensitivity of the power meter to such reflections can be
characterized by the parameter spectra ripple, determined as the periodic change in responsivity vs. the
wavelength of a coherent light source.

4.3 Temporary joint (TJ)
This is a method, device or mechanical fixture for temporarily aligning two fibre ends into a
stable, reproducible, low-loss joint. It is used when direct connection of the DUT to the
measurement system is not achievable by a standard connector. It may, for example, be a
precision V-groove, vacuum chuck, a micromanipulator or a fusion or mechanical splice. The
temporary joint shall be stable to within ±10 % of the required measurement accuracy in dB
over the time taken to measure P and P . A suitable refractive index matching material may
0 1
be used to improve the stability of the TJ.
4.4 Fibre
The fibre in the lead from the source to the temporary joint, in the test patchcord, and in the
substitute patchcord, shall belong to the same category as that used in the DUT.
Fibres should be in accordance with IEC 60793-2.

– 8 – 61300-3-4 © IEC:2012
4.5 Reference plugs (RP)
Where reference plugs are required to form complete connector assemblies in any of the test
methods, the reference plugs become in effect a part of the DUT during the measurement of
attenuation. Reference plugs shall be specified in the relevant specification.
4.6 Reference adaptors (RA)
Where reference adaptors are required to form complete connector assemblies in any of the
test methods, the reference adaptors become in effect a part of the DUT during the
measurement of attenuation. Reference adaptors shall be specified in the relevant
specification.
5 Procedure
5.1 Pre-conditioning
The optical interfaces of the DUT shall be clean and free from any debris likely to affect the
performance of the test and any resultant measurements. The manufacturer’s cleaning
procedure shall be followed.
The DUT shall be allowed to stabilize at room temperature for at least 1 h prior to testing.
Care should be exercised throughout the test to ensure that mating surfaces are not
contaminated with oil or grease. It is recognized that bare fingers can deposit a film of grease.
5.2 Visual inspection
The optical interfaces shall be free from defects or damage which may affect the performance
of the test and any resultant measurements. It is recommended that a visual inspection of the
optical interfaces of the DUT is made in accordance with IEC 61300-3-1 prior to the start of
the test.
5.3 DUT configurations and test methods
Table 3 – DUT configurations
Test methods
Reference test Alternative
Type Description DUT
method test method
RTM ATM
1 Fibre to fibre Power meter OTDR
(component) (cutback)
2 Fibre to fibre Power meter Power meter
(splice or field-mountable (insertion A) (cutback)

connector set)
Or OTDR
3 Fibre to plug Power meter OTDR

(cutback)
4 Plug to plug Power meter Power meter
(component) (insertion B) (insertion C)
C
Or OTDR
5 Plug to plug Power meter Power meter
(patchcord) (insertion B) (insertion C)

Or OTDR
61300-3-4 © IEC:2012 – 9 –
Test methods
Reference test Alternative
Type Description DUT
method test method
RTM ATM
6 Single plug
Power meter OTDR
(pigtail) (insertion B)
7 Receptacle to Power meter Power meter
receptacle (insertion C) (substitution)
(component) Or OTDR
8 Receptacle to plug Power meter Power meter
(insertion C) (substitution)
(component)
Or OTDR
C is a passive optical component which may have more than the two ports indicated. Insertion
measurements and cutback measurements may be expected to give equivalent
measurements for type 2 DUTs.
Due to measurement considerations, the OTDR method may be less accurate than other
measurement methods but may be the only test applicable.
An OTDR can be used on components with more than two ports, but in this case the reflected
power from the ports not being measured should be suppressed in the attenuation zone.
5.4 Attenuation measurements with a power meter
5.4.1 General
The measurement of attenuation using cutback, substitution or insertion is based on the use
of an optical power meter,as described in 4.2.
Two measurements of power are required for each measurement of attenuation, A, with a
power meter:
P
A=−10log dB (1)
P
where
P is the measurement of power with the DUT in the path;
P is the measurement of power without the DUT in the path.
Suitable connections shall be provided between the fibre and the detector. Connections may
be with either an adaptor to connect a bare fibre or with a connector adaptor for the
appropriate connector.
5.4.2 Cutback method
For a type 1 and type 2 DUT, one lead of the DUT is connected to the source with a TJ. The
other lead is connected to the detector, and P is measured (see Figure 1). The fibre is cut at
CP, and P is measured.
– 10 – 61300-3-4 © IEC:2012
CP
S
DUT D
PM
TJ
P
IEC  2176/12
CP
S
D
PM
TJ
P
Figure 1 – Cutback method – Type 1, Type 2 and Type 3 DUTs
For a Type 3, fibre-to-plug DUT, a reference adaptor and a reference plug with a pigtail are
added to the DUT to form a complete connector assembly. Attenuation of a Type 3 DUT is the
attenuation of the complete connector assembly with pigtail leads, and is measured as a
Type 1 DUT.
5.4.3 Substitution method
In the substitution method, P is measured with the DUT in the circuit, and P is measured
with a substitute patchcord in place of the DUT (see Figure 2).
For a type 4 DUT, reference adaptors are added to the reference plugs on both the source
lead and the test patchcord (see Figure 2).
Test
Substitute
patchcord
patchcord
RA
RA
S
D
PM
RP RP RP RP
TJ
P
IEC  2178/12
Test
patchcord
DUT
RA RA
S
C D
PM
TJ RP RP
P
IEC  2179/12
Figure 2 – Substitution method – Type 4 DUT

61300-3-4 © IEC:2012 – 11 –
For a Type 7 DUT, the measurement is made in the same way as a plug-to-plug DUT, except
that reference adaptors are not required for the measurement of P (see Figure 2).
For a Type 8 DUT the measurement is made in the same way as for a plug-to-plug DUT,
except that only one reference adaptor is required for the measurement of P (see Figure 2).
In this case, the reference adaptor shall be the one nearest the source.
Substitution measurements may be expected to give somewhat lower results of attenuation
than insertion measurements for types 4, 5, 6, and 7 DUTs. This is due to the fact that in the
substitution method the reference power P includes the attenuation of the ‘substitute
patchcord’ with its connections to the measurement system. Therefore, the value of P in the
substitution method is lower than in the insertion method.
5.4.4 Insertion method (A)
For a type 2 fibre-to-fibre DUT (splice- or field-mountable connector set), P is measured with
a length of fibre between the temporary joint and the detector, the fibre is cut, the splice- or
field-mountable connector set is installed, and P is measured (see Figure 3).
S
D
PM
TJ
P
0 IEC  2180/12
S
D
PM
Splice
TJ
P
IEC  2181/12
Figure 3 – Insertion method (C1) – Type 2 DUT
5.4.5 Insertion method (B) with direct coupling to power meter
For a Type 5 and Type 6 DUT, P is measured with the detector connected to a reference
plug on the fibre from the temporary joint. A reference adaptor and the DUT are added, and
P is measured (see Figure 4).
– 12 – 61300-3-4 © IEC:2012
S
D
PM
TJ
RP
P
IEC  2182/12
DUT
RA
S
D
PM
RP
TJ
P
IEC  2183/12
Figure 4 – Insertion method (C2) – Type 5 and Type 6 DUT
This measurement includes only the plug on the source end of the DUT in the measurement.
To measure both ends of the DUT the measurement shall be repeated with the patchcord
reversed.
For a Type 6 DUT the measurement requires an adaptor for a bare fibre at the detector.
5.4.6 Insertion method (C) with additional test patchcord
For a Type 4 plug-to-plug (component) DUT or a type 5 plug-to-plug (patchcord) DUT, P is
measured with the test patchcord connected between the detector and the lead from the
temporary joint. The DUT and another reference adaptor are added, to measure P (see
Figure 5).
61300-3-4 © IEC:2012 – 13 –
Test patchcord
RA
S
D
PM
TJ RP
RP
P
IEC  2184/12
Test
patchcord
DUT
RA RA
S
C D
PM
TJ RP RP
P
IEC  2185/12
Figure 5 – Insertion method (C3) – Type 4, Type 5, Type 7 and Type 8 DUT
For a Type 7 receptacle-to-receptacle DUT, reference adaptors are not required for the
measurement of P .
For a Type 8 receptacle-to-plug DUT, only one reference adaptor is required for the
measurement of P .
5.5 Attenuation measurements with an OTDR
5.5.1 Measurement description
An OTDR measures the level of radiation scattered back by the optical line and collected by
the receiver of the instrument. Using an OTDR, it is possible to measure and to evaluate both
point events due, for example, to passive components such as splices, connectors,
attenuators, etc. or losses due to the attenuation of fibre sections terminated by passive
components.
There are two principal measurement methods used depending on the DUT configuration (see
Table 3):
Method 1 – One launch section (see Figure 6) is applicable to DUT Types 1, 2, 3;
Method 2 – Two launch sections (see Figure 7) is applicable to DUT Types 4, 5, 6, 7, 8.

– 14 – 61300-3-4 © IEC:2012
b
a
LS1
DUT
OTDR
L L
1 X
IEC  2186/12
Figure 6 – Method 1 – One launch section

a
b
LS2
LS1
OTDR
DUT
L L L
1 X 2
IEC  2187/12
Figure 7 – Method 2 – Two launch sections
Fibre launch sections LS1 and LS2 provide separation between the OTDR equipment and the
events to be measured and ensure stable measurement conditions. Their minimum length is
determined by the ability of the OTDR to resolve the measurement of attenuation and is
commonly referred to as the attenuation dead zone (DZ ). The maximum length of the launch
att
section is limited by requirement to minimize the OTDR distance resolution and to minimize
optical losses of measured route.
If the DUT section length L is greater than the OTDR resolution (L > DZ ), then the
X X att
attenuation for each event, a and b, will be displayed separately. Where L < DZ , the OTDR
X att
will be unable to distinguish between events a and b and the DUT will be shown as one
attenuation event.
Where the DUT is terminated with either a connector plug or a receptacle, reference plugs
and adaptors are added, as necessary, to form complete connector assemblies. These
connector assemblies are considered part of the DUT.
Where the component has pigtails, connector points are required. The pigtail lengths shall be
greater than the OTDR resolution for each event to be displayed separately.
5.5.2 Bidirectional measurement
The value of attenuation is determined from the intensity difference of back-scattering before
and after the DUT, so the launch section LS2 is needed if the DUT does not itself have
sufficiently long pigtails, compared to the dead zone. Since the backscattering coefficient of
the fibre before and after the DUT can differ, the OTDR measurement shall be made from
both ends of the assembly of DUT and launch sections, without changing the ordering of this
assembly. The attenuation result is the average of the apparent attenuation from the two
OTDR measurements.
Differences in the backscatter coefficient of the fibre on either side of the DUT will result in an
error in a one-way OTDR measurement. The error in a measurement made in one direction
will be positive and the error in the other direction will be negative. The use of an average of
readings taken in opposite directions cancels the error due to differences in the backscatter
coefficient of the two fibres.

61300-3-4 © IEC:2012 – 15 –
Referring to the two measured attenuation values, illustrated in 5.5.4, as A and A , the
1 2
average attenuation is calculated as:
A+ A
1 2
A= (dB). (2)
See IEC/TR 62316 for further details.
5.5.3 Measurement method
– Configure the apparatus as shown in Figure 6 or Figure 7 with the OTDR equipment
connected to side a.
– Set the OTDR measurement characteristics.
– Take an attenuation measurement in direction a-b and save the resulting OTDR data for
evaluation.
– Configure the apparatus as shown in Figure 6 or Figure 7 with the OTDR equipment
connected to side b.
– Set the same OTDR measurement characteristics as for the side a.
– Take an attenuation measurement in direction b-a and save the resulting OTDR data for
evaluation.
5.5.4 Evaluation procedure
5.5.4.1 General
A typical OTDR display of the backscatter signal from a DUT with a non-reflective event is
illustrated in Figure 8a and Figure 8b.

(1) (1)
(5)
≡
(2)  (2a)
(2)
A
A
(3) ≡
(3)  (3a)
(4) (4)
IEC  2188/12 IEC  2189/12
Figure 8a – Five-point evaluation   Figure 8b – Four-point evaluation
Figure 8 – Non-reflective event
A typical OTDR display of the backscatter signal from a DUT with a reflective event is
illustrated in Figure 9a and Figure 9b. To avoid the reflection peak affecting the attenuation
measurement, the distance between the reference markers and the peak should be suitably
long. Alternatively, a suitable filter, specified in the relevant specification, should be used to
mask the reflection.
– 16 – 61300-3-4 © IEC:2012
(1)
(1)
(5)
≡
(2) ( 2a)
(2)
A
A
≡
(3) (3a)
(3)
(4)
(4)
IEC  2190/12 IEC  2191/12
Figure 9a – Five-point evaluation  Figure 9b – Four-point evaluation
Figure 9 – Reflective event
5.5.4.2 Five-point evaluation
Set evaluation points (1) and (2) on the fibre section in front of the DUT and (3) and (4) on the
fibre section behind the DUT. Set the position of decision point (5). Attenuation, A, shall be
calculated as the power level difference at point (5) between the least squares approximation
curve of the fibre section in front of the DUT and the least squares approximation curve of the
fibre behind the DUT.
5.5.4.3 Four-point evaluation
Set evaluation points (1) and (2) on the fibre section in front of the DUT and (3) and (4) on the
fibre section behind the DUT. Attenuation, A, shall be calculated as the power-level difference
between point (2a) of the least squares approximation curve of the fibre section in front of the
DUT and point (3a) of least squares approximation curve of the fibre behind the DUT.
6 Details to be specified
The following details, as applicable, shall be specified in the relevant specification:
– test method;
– source characteristics;
– performance requirements (allowable attenuation);
– power meter characteristics;
– relevant fibre parameters;
– OTDR characteristics
• wavelength,
• refractive index value used,
• range,
• pulse width,
• averaging time,
• lengths L , L , L ;
1 2 x
– deviations from this test method.

61300-3-4 © IEC:2012 – 17 –
Bibliography
IEC 61300-3-29, Fibre optic interconnecting devices and passive components – Basic test
and measurement procedures – Part 3-29 Examinations and measurements – Measurement
techniques for characterizing the amplitude of the spectral transfer function of DWDM
components
IEC 61280-1-3, Fibre optic communication subsystem test procedures – Part 3-1: General
communication subsystems – Central wavelength and spectral width measurement

_____________
– 18 – 61300-3-4 © CEI:2012
SOMMAIRE
AVANT-PROPOS . 20
1 Domaine d’application . 22
2 Références normatives . 22
3 Description générale. 22
3.1 Généralités . 22
3.2 Précautions à prendre . 23
4 Appareillage . 24
4.1 Conditions d’injection et source (S) . 24
4.2 Appareil de mesure de la puissance optique (D) . 24
4.3 Jonction temporaire (TJ) . 25
4.4 Fibre . 25
4.5 Fiches de référence (RP) . 25
4.6 Raccords de référence (RA) . 25
5 Procédure. 26
5.1 Pré-conditionnement . 26
5.2 Contrôle visuel . 26
5.3 Configurations du DUT et méthodes d'essai . 26
5.4 Mesures de l’affaiblissement au moyen d’un appareil de mesure de la
puissance . 27
5.4.1 Généralités . 27
5.4.2 Méthode de la fibre coupée . 27
5.4.3 Méthode par substitution . 28
5.4.4 Méthode par insertion (A) . 29
5.4.5 Méthode par insertion (B) avec couplage direct avec l'appareil de
mesure de la puissance . 29
5.4.6 Méthode par insertion (C) avec cordon de brassage supplémentaire . 30
5.5 Mesures de l’affaiblissement au moyen d'un OTDR . 31
5.5.1 Description de la mesure . 31
5.5.2 Mesure bidirectionnelle . 32
5.5.3 Méthode de mesure . 33
5.5.4 Procédure d’évaluation . 33
6 Détails à spécifier . 34
Bibliographie . 35

Figure 1 – Méthode de la fibre coupée – DUT de Type 1, de Type 2, et de Type 3 . 28
Figure 2 – Méthode par substitution – DUT de Type 4 . 28
Figure 3 – Méthode par insertion (C1) – DUT de Type 2 . 29
Figure 4 – Méthode par insertion (B) – DUT de Type 5 et de Type 6 . 30
Figure 5 – Méthode par insertion (C3) – DUT de Type 4, de Type 5, de Type 7 et de
type 8 . 31
Figure 6 – Méthode 1 – Un tronçon d’injection . 32
Figure 7 – Méthode 2 – Deux tronçons d’injection .
...