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BS EN 61300-3-45:2011 BSI Standards Publication Fibre optic interconnecting devices and passive components — Basic test and measurement procedures Part 3-45: Examinations and measurements — Attenuation of random mated multi-fibre connectors BRITISH STANDARD BS EN 61300-3-45:2011 National foreword This British Standard is the UK implementation of EN 61300-3-45:2011 It is identical to IEC 61300-3-45:2011 The UK participation in its preparation was entrusted by Technical Committee GEL/86, Fibre optics, to Subcommittee GEL/86/2, Fibre optic interconnecting devices and passive components A list of organizations represented on this committee can be obtained on request to its secretary This publication does not purport to include all the necessary provisions of a contract Users are responsible for its correct application © BSI 2011 ISBN 978 580 64523 ICS 33.180.20 Compliance with a British Standard cannot confer immunity from legal obligations This British Standard was published under the authority of the Standards Policy and Strategy Committee on 31 July 2011 Amendments issued since publication Amd No Date Text affected BS EN 61300-3-45:2011 EUROPEAN STANDARD EN 61300-3-45 NORME EUROPÉENNE June 2011 EUROPÄISCHE NORM ICS 33.180.20 English version Fibre optic interconnecting devices and passive components Basic test and measurement procedures Part 3-45: Examinations and measurements Attenuation of random mated multi-fibre connectors (IEC 61300-3-45:2011) Dispositifs d'interconnexion et composants passifs fibres optiques Méthodes fondamentales d'essais et de mesures Partie 3-45: Examens et mesures Affaiblissement dû l'accouplement de connecteurs quelconques multifibres (CEI 61300-3-45:2011) Lichtwellenleiter Verbindungselemente und passive Bauteile Grundlegende Prüf- und Messverfahren Teil 3-45: Untersuchungen und Messungen Dämpfung von zufällig gesteckten Mehrfasersteckverbindern (IEC 61300-3-45:2011) This European Standard was approved by CENELEC on 2011-06-16 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, Bulgaria, Croatia, Cyprus, the Czech Republic, Denmark, Estonia, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia, Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Slovakia, Slovenia, Spain, Sweden, Switzerland and the United Kingdom CENELEC European Committee for Electrotechnical Standardization Comité Européen de Normalisation Electrotechnique Europäisches Komitee für Elektrotechnische Normung Management Centre: Avenue Marnix 17, B - 1000 Brussels © 2011 CENELEC - All rights of exploitation in any form and by any means reserved worldwide for CENELEC members Ref No EN 61300-3-45:2011 E BS EN 61300-3-45:2011 EN 61300-3-45:2011 -2- Foreword The text of document 86B/3177/FDIS, future edition of IEC 61300-3-45, 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 61300-3-45 on 2011-06-16 Attention is drawn to the possibility that some of the elements of this document may be the subject of patent rights CEN and CENELEC shall not be held responsible for identifying any or all such patent rights 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) 2012-03-16 – latest date by which the national standards conflicting with the EN have to be withdrawn (dow) 2014-06-16 Annex ZA has been added by CENELEC Endorsement notice The text of the International Standard IEC 61300-3-45:2011 was approved by CENELEC as a European Standard without any modification -3- BS EN 61300-3-45:2011 EN 61300-3-45:2011 Annex ZA (normative) Normative references to international publications with their corresponding European publications The following referenced documents are indispensable for the application 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 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 61300-1 - Fibre optic interconnecting devices and passive components - Basic test and measurement procedures Part 1: General and guidance EN 61300-1 - IEC 61300-3-1 - Fibre optic interconnecting devices and passive components - Basic test and measurement procedures Part 3-1: Examinations and measurements Visual examination EN 61300-3-1 - IEC 61300-3-35 - EN 61300-3-35 Fibre optic interconnecting devices and passive components - Basic test and measurement procedures Part 3-35: Examinations and measurements Fibre optic cylindrical connector endface visual and automated inspection IEC 61754 Series Fibre optic connector interfaces EN 61754 - Series –2– BS EN 61300-3-45:2011 61300-3-45  IEC:2011 CONTENTS Scope Normative references General description 3.1 Test methods 3.2 Precautions Apparatus 4.1 Source (S) 4.2 Launch conditions (E) 4.3 Detector (D) Procedure 5.1 Method 5.2 Method 10 5.3 Analysis of results 13 Details to be specified 13 Figure – “Reference” cord measurement – Method Figure – Test cord measurement – Method Figure – Test matrix and labelling for measuring method (2-fibre connector) Figure – Test matrix and labelling for measuring method (4-fibre connector) 10 Figure – Test matrix and labelling for measuring method (8, 10, 12-fibre connector) 10 Figure – “Reference” cord measurement (1) – Method 11 Figure – Test cord measurement (1) – Method 11 Figure – “Reference” cord measurement (2) – Method 12 Figure – Test cord measurement (2) – Method 12 Figure 10 – Test matrix and labelling for measuring method (2-fibre connector) 12 Figure 11 – Test matrix and labelling for measuring method (4-fibre connector) 13 Figure 12 – Test matrix and labelling for measuring method (8, 10, 12-fibre connector) 13 Table – Sample size for Method Table – Sample size for Method BS EN 61300-3-45:2011 61300-3-45  IEC:2011 –5– FIBRE OPTIC INTERCONNECTING DEVICES AND PASSIVE COMPONENTS – BASIC TEST AND MEASUREMENT PROCEDURES – Part 3-45: Examinations and measurements – Attenuation of random mated multi-fibre connectors Scope The purpose of this part of IEC 61300 is to describe the procedure required to measure the statistical distribution and mean attenuation for random mated optical connectors with physical contact (PC) and angled physical contact (APC) polished 1-row multi-fibre rectangular ferrules as defined in the IEC 61754 series This measurement method is applicable to cable assemblies Normative references The following referenced documents are indispensable for the application 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 61300-3-1, Fibre optic interconnecting devices and passive components – Basic test and measurement procedures – Part 3-1: Examinations and measurements – Visual examination IEC 61300-3-35, Fibre optic interconnecting devices and passive components – Basic test and measurement procedures – Part 3-35: Examinations and measurements – Fibre optic connector endface visual and automated inspection IEC 61754 (all parts), Fibre optic connector interfaces 3.1 General description Test methods Two test methods are described for measuring the attenuation of random mated optical connectors Both provide an estimate of the expected average performance that a group of cable assemblies (including an adaptor, if applicable) selected from a batch will exhibit when used in an optical system The cable assemblies, and any adaptors, must be chosen at random to ensure that the measurements provide a statistically unbiased estimate Method describes the procedure using a sample of cable assemblies and adaptors specified in Table In this case the plugs (with pins) are used as “reference” plugs and the plugs (without pins) are tested against them sequentially The results, based on the number of measurements specified in Table 1, are recorded in the test matrix shown in Figures to Method is intended to be part of a design approval exercise that may involve one or more suppliers Once approval is achieved, Method would be relied on to maintain process control However, in the event of a dispute, Method shall act as the reference measurement method BS EN 61300-3-45:2011 61300-3-45  IEC:2011 –6– Method describes a procedure for the measurement of a sample of cable assemblies specified in Table Three cable assemblies are selected from the sample as “reference” cable assemblies and pins are fitted The other test cable assemblies (without pins) are tested against each of the three “reference cable assemblies” sequentially This produces the number of measurements specified in Table and the results are recorded in the test matrix shown in Figures 10 to 12 It is recognised that the number of measurements required by Method may be excessive for day-to-day routine checking of either in-house or supplier produced products In this case, as indicated above, Method may be an alternative option NOTE In this measurement method, the terms “reference” plug or “reference” cord are used to define those components chosen at random from a batch, against which a number of comparative measurements are made It is not intended that the terms should imply specially chosen or manufactured components, such as those used, for example, in screen testing Table – Sample size for Method Connector Sample size (n-fibre connector) Cord and adaptors Measurements Fibres 2-fibre connector 15 210 420 4-fibre connector 12 132 528 8-fibre connector 10 90 720 10-fibre connector 10 90 900 12-fibre connector 10 90 080 Measurements Fibres Table – Sample size for Method Sample size Connector (n-fibre connector) Cord and adaptors Total Reference Test :N 2-fibre connector 12 54 108 4-fibre connector 30 120 8-fibre connector 3 18 144 10-fibre connector 3 18 180 12-fibre connector 3 18 216 3.2 Precautions The following test requirements shall be met a) Precautions shall be taken to ensure that the cladding modes not affect the measurement Cladding modes shall be stripped as a function of the fibre coating b) Precautions shall be taken to ensure that the position of the fibres in the test remains fixed between the measurement of P and P to avoid changes in attenuation due to bending losses c) The stability performance of the test equipment shall be ≤ 0,05 dB or 10 % of the attenuation to be measured, whichever is the lower value The stability shall be maintained over the measurement time and operational temperature range The required measurement resolution shall be 0,01 dB for both multimode and single mode BS EN 61300-3-45:2011 61300-3-45  IEC:2011 –7– d) To achieve consistent results, clean and inspect all connectors and adaptors prior to measurement Visual examination shall be undertaken in accordance with IEC 61300-3-1 and IEC 61300-3-35 NOTE A cladding mode stripper usually comprises a material having a refractive index equal to or greater than that of the fibre cladding Apparatus 4.1 Source (S) The source consists of an optical emitter, the means to connect to it and associated drive electronics In addition to meeting the stability and power level requirements, the source shall have the following characteristics: – Centre wavelength, as detailed in the performance and product standard; – Spectral width, filtered light emitting diode (LED) ≤ 150 nm full width half maximum (FWHM); – Spectral width, laser diode (LD) < 10 nm FWHM For multimode fibres, broadband sources such as an LED shall be used For single mode fibres either an LED or LD may be used NOTE The interference of modes from a coherent source will create speckle patterns in multimode fibres These speckle patterns give rise to speckle or modal noise and are observed as power fluctuations, since their characteristic times are longer than the resolution time of the detector As a result, it may be impossible to achieve stable launch conditions using coherent sources for multimode measurements Consequently, lasers, including optical time domain reflectometer (OTDR) sources, should be avoided in favour of LEDs or other incoherent sources for measuring multimode components 4.2 Launch conditions (E) The launch condition shall be specified in accordance with IEC 61300-1 4.3 Detector (D) The detector consists of an optical detector, the means to connect to it and associated electronics The connection to the detector will be an adaptor that accepts a connector plug of the appropriate design The detector shall capture all light emitted by the connector plug In addition to meeting the stability and resolution requirements, the detector shall have the following characteristics: – Linearity of multimode, ≤ ±0,25 dB (over −5 dBm up to −60 dBm); – Linearity of single mode, ≤ ±0,1 dB (over −5 dBm up to −60 dBm) NOTE The power meter linearity should be referenced to a power level of −23 dBm at the operational wavelength Where the connection to the detector is broken between the measurement of P and P , the measurement repeatability shall be within 0,05 dB or 10 % of the attenuation to be measured, whichever is the lower value A large sensitive area detector 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 device under test (DUT) at the wavelength being measured BS EN 61300-3-45:2011 61300-3-45  IEC:2011 –8– Procedure 5.1 Method a) Randomly select the sample number of cable assemblies specified in Table Sequentially label the plugs under test as shown in Figures to b) Randomly select the sample size of adaptors as specified in Table Sequentially label the adaptors under test as shown in Figures to c) Set up the measurement system as shown in Figure 1, with cord 1as the “reference” cord and with plug as the “reference” plug Measure power P 1-1 to P 1-n for all fibres in the cord S “Reference” cord Fan-out cord Ch D E Plug 1(without pins) Plug 1(with pins) Ch n P1-n IEC 900/11 Figure – “Reference” cord measurement – Method d) Connect test cord and adaptor to the system and mate plug (with pins) to plug (without pins) as shown in Figure Measure the power P 2-1 to P 2-n for all fibres in the cord Ch Test cord D E S Adaptor “Reference” cord Fan-out cord Plug (without pins) Plug (with pins) Plug (without pins) Plug (with pins) P2-n Ch n IEC 901/11 Figure – Test cord measurement – Method e) Calculate the attenuation of the mated plug pair (with pins) / (without pins) with adaptor 1, using Equation (1): Attenuation = [-10 log (P 2-i /P 1-i )] - (A × L) dB (1) Where i is fibre number of Test cord A is fibre attenuation per km; L is length of fibre in km NOTE The product A × L may be ignored for both single mode and multimode [50/125 µm and 62,5/125 µm] where the cord length is small, i.e < 10 m f) Record the attenuation results for each fibre into an appropriate matrix format NOTE An example of record table (for fibre connectors) is shown in Figure 13 g) Keeping plug (with pins) and adaptor as the “reference” configuration, replace test cord by test cord and mate plug (without pins) with plug (with pins) BS EN 61300-3-45:2011 61300-3-45  IEC:2011 –9– h) Measure the power P 3-1 to P 3-n and record the attenuation results for each fibre i) Repeat steps g) and h) until all the plugs (without pins) of the remaining test cable assemblies have been tested against the “reference” plug (with pins) j) After step i) has been completed, replace the “reference” plug and adaptor so that plug (with pins) and adaptor are the “reference” configuration k) Measure the attenuation for all plugs against “reference” plug (with pins) and adaptor l) Continue this process until all allocated plugs have been used as “reference” plugs “ Reference” Configuration Plug (with pins) Adaptor Plug (with pins) Adaptor Plug (with pins)) Adaptor Plug (with pins) Adaptor Plug (with pins) Adaptor Plug (with pins) Adaptor Plug (with pins) Adaptor Plug (with pins) Adaptor Plug (with pins) Adaptor Plug 10 (with pins) Adaptor 10 Plug 11 (with pins) Adaptor 11 Plug 12 (with pins) Adaptor 12 Plug 13 (with pins) Adaptor 13 Plug 14 (with pins) Adaptor 14 Plug 15 (with pins) Adaptor 15 Test cord and labelling Plug (without pins) 10 11 12 13 14 15 IEC Figure – Test matrix and labelling for measuring Method (2-fibre connector) 902/11 BS EN 61300-3-45:2011 61300-3-45  IEC:2011 – 10 – “ Reference” configuration Plug (with pins) Adaptor Plug (with pins) Adaptor Plug (with pins) Adaptor Plug (with pins) Adaptor Plug (with pins) Adaptor Plug (with pins) Adaptor Plug (with pins) Adaptor Plug (with pins) Adaptor Plug (with pins) Adaptor Plug 10 (with pins) Adaptor 10 Plug 11 (with pins) Adaptor 11 Plug 12 (with pins) Adaptor 12 Test cord and labelling Plug (without pins) 10 11 12 IEC 903/11 Figure – Test matrix and labelling for measuring Method (4-fibre connector) “ Reference” configuration Plug (with pins) Adaptor Plug (with pins) Adaptor Plug (with pins) Adaptor Plug (with pins) Adaptor Plug (with pins) Adaptor Plug (with pins) Adaptor Plug (with pins) Adaptor Plug (with pins) Adaptor Plug (with pins) Adaptor Plug 10 (with pins) Adaptor 10 Test cord and labelling Plug (without pins) 10 IEC 904/11 Figure – Test matrix and labelling for measuring Method (8, 10, 12-fibre connector) 5.2 Method a) Randomly select the sample number of cable assemblies specified in Table b) Choose three cable assemblies at random and sequentially label the plugs of each cord as “reference” plugs Sequentially label the plugs of the remaining cable assemblies as test plugs Sequentially label three adaptors to (as shown in Figures 10 to 12) c) Set up the measurement system as shown in Figure 6, with “reference” cord so that the plug (with pins) is the “reference” plug Measure power P 1-1 to P 1-n for all fibres in the cord BS EN 61300-3-45:2011 61300-3-45  IEC:2011 – 11 – S “Reference” cord Fan-out cord Ch D E Plug (without pins) Plug (with pins) Ch n P1-n IEC 905/11 Figure – “Reference” cord measurement (1) – Method d) Connect test cord and adaptor to the measurement system and mate reference plug (with pins) with test plug (without pins) as shown in Figure Measure the power P 2-1 to P 2-n Ch Test cord D E S Adaptor “Reference” cord Fan-out cord Plug (without pins) Plug (with pins) Plug (without pins) Plug (with pins) P2-n Ch n IEC 906/11 Figure – Test cord measurement (1) – Method e) Calculate the attenuation of the mated plug pair (with pins) / (without pins) with adaptor 1, using Equation (2): Insertion loss = [-10 log (P 2-i /P 1-i )] - (A × L) dB (2) Where i is fiber number of Test cord A is fibre attenuation per km L is length of fibre in km NOTE The product A × L may be ignored for both single mode and multimode [50/125 µm and 62.5/125 µm] where the cord length is small, i.e < 10 m f) Record the attenuation results for each fibre into an appropriate matrix format g) Repeat steps d) to f) until all test plugs (without pins) have been tested against “reference” plug (with pins) and adaptor h) After step g) has been completed, replace the “reference” plug and adaptor so that “reference” plug (with pins) and adaptor are the “reference” configuration i) Measure the attenuation for all test plugs (without pins) against “reference” plug (with pins) and adaptor 2, using the procedures described above j) Continue this process until all allocated “reference” plugs (with pins) and adaptors have been used and all test cable assemblies (without pins) have been tested k) S et up the measurement system shown in Figure 8, with “reference” cord so that the plug (without pins) is the “reference” plug, Measure power P 1-1 to P 1-n for all fibres in the cord BS EN 61300-3-45:2011 61300-3-45  IEC:2011 – 12 – “Reference” cord Fan-out cord Ch S D E Plug (with pins) Plug (without pins) Ch n P1-n IEC 907/11 Figure – “Reference” cord measurement (2) – Method l) Connect test cord and adaptor to the measurement system and mate “reference” plug (without pins) with test plug (with pins) as shown in Figure Measure the power P 2-1 to P 2-n Ch Fan-out cord Test cord D E S Adaptor “Reference” cord Plug (without pins) Plug Plug (without pins) (with pins) Plug (with pins) P2-n Ch n IEC 908/11 Figure – Test cord measurement (2) – Method m) Calculate the attenuation of the mated plug pair (without pins) / (with pins) with adaptor 1, using the equation given above n) Record the attenuation results for each fibre into an appropriate matrix format o) Repeat steps l) to n) until all test plugs (with pins) have been tested against the “reference” plug (without pins) and adaptor p) After step m) has been completed, replace the “reference” plug and adaptor so that “reference” plug (without pins) and adaptor are the “reference” configuration q) Measure the attenuation for all test plugs (with pins) against “reference” plug (without pins) and adaptor 2, using the procedures described above r) Continue this process until all allocated “reference” plugs (without pins) and adaptors have been used and all test cable assemblies (with pins) have been tested “ Reference” Configuration (1) “Reference” Plug Adaptor Plug (with pins) Adaptor Plug (with pins) Adaptor Plug (with pins) Adaptor “ Reference” Configuration (2) “Reference” Plug Adaptor Plug (without pins) Adaptor Plug (without pins) Adaptor Plug (without pins) Adaptor Test cord and labelling Test plug (without pins) 9 Test cord and labelling Test plug (with pins) IEC 909/11 Figure 10 – Test matrix and labelling for measuring Method (2-fibre connector) BS EN 61300-3-45:2011 61300-3-45  IEC:2011 – 13 – “ Reference” Configuration (1) “Reference” Plug Adaptor Plug (with pins) Adaptor Plug (with pins) Adaptor Plug (with pins) Adaptor “ Reference” Configuration (2) “Reference” Plug Adaptor Plug (without pins) Adaptor Plug (without pins) Adaptor Plug (without pins) Adaptor Test cord and labelling Test plug (without pins) Test cord and labelling Test plug (with pins) IEC 910/11 Figure 11 – Test matrix and labelling for measuring Method (4-fibre connector) “ Reference” Configuration (1) “Reference” Plug Adaptor Plug (with pins) Adaptor Plug (with pins) Adaptor Plug (with pins) Adaptor “ Reference” Configuration (2) “Reference” Plug Adaptor Plug (without pins) Adaptor Plug (without pins) Adaptor Plug (without pins) Adaptor Test cord and labelling Test plug (without pins) Test cord and labelling Test plug (with pins) IEC 911/11 Figure 12 – Test matrix and labelling for measuring Method (8, 10, 12-fibre connector) 5.3 Analysis of results The mean value and 97 % percentile values of the measurement data from all the fibres of either Method or Method 2, shall comply with the values specified in the relevant connector performance standard Details to be specified The following details, as applicable, shall be specified in the relevant specification • Performance characteristics (allowable attenuation, statistical variation, etc.) • Source wavelength • Fibre attenuation per km • Deviations from this test method _ This page deliberately left blank This page deliberately left blank NO COPYING WITHOUT BSI PERMISSION EXCEPT AS PERMITTED BY COPYRIGHT LAW British Standards Institution (BSI) BSI is the national body responsible for preparing British Standards and other standards-related publications, information and services BSI is incorporated by Royal Charter British Standards and other standardization products are published by BSI Standards Limited About us Revisions We bring together business, industry, government, consumers, innovators and others to shape their combined experience and expertise into standards -based solutions Our British Standards and other publications are updated by amendment or revision The knowledge embodied in our standards has been carefully 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