Fibre opt ic int erconnect ing devices and passive component s – Fibre opt ic connect or int er aces – Part 31: Ty e N- FO connect or fami y Disposit ifs d’ nt erconnexion et composants
General
The N-FO connector family includes two-way and four-way circular plug connectors and socket sets Each plug connector features a spring-loaded threaded coupling nut and a single keyway in the plug shell for proper orientation with the mating socket The connectors utilize 1.25 mm non-angle polished ferrules, which are aligned with resilient sleeves contained within the plug.
Two way system
This system consists of two spring loaded ferrules within each connector body The pitch between the two fibre centres is nominally 3,0 mm
It has a threaded coupling mechanism, which is designed to be tightened to a torque of 1 Nm to 2 Nm.
Four way system
This system consists of four spring loaded ferrules in a row within each connector body The pitch between any two adjacent fibre centres is nominally 2,50 mm
It has a threaded coupling mechanism, which is designed to be tightened to a torque of 1 Nm to 2 Nm
General requirements defined in IEC 61 754-1 are valid for this standard
This standard contains the following standard interfaces:
Interface IEC 61 754-31 -1 : two way plug connector interface
Interface IEC 61 754-31 -2: two way socket connector interface
Interface IEC 61 754-31 -3: four way plug connector interface
Interface IEC 61 754-31 -4: four way socket connector interface
The following plugs and sockets shown in Table 1 are intermateable
Table 1 – Intermateability between plugs and sockets within the IEC 61 754-31 series of interfaces
Two way plug connector interface
The plug connector is illustrated in Figure 1, while Figure 2 and Table 2 detail the two-way plug connector interface It features a resilient split alignment sleeve that accommodates a pin gauge at its center, requiring a force between 1.0 N and 2.5 N for proper alignment This occurs when the plug ferrule is inserted from the opposite side until the pin gauge and plug ferrule make contact The nominal size of the pin gauge is 1.2490 mm, as specified in Table 8.
Figure 1 – Two way plug connector (isometric view)
Figure 2 – Two way plug connector mating dimensions
Optical reference plane Mechanical reference plane
Table 2 – Two way plug connector dimensions
The finished ferrule endface is specified with a dimension N of 34.1 to 50.55 ± 5 Shore A This spring-loaded ferrule is adjustable under axial compression, making dimension N variable The required compression force for the ferrule should range between 5.0 N and 6.0 N when dimension N is set between 3.5 mm and 3.7 mm It is important to note that these force values apply only to buffered fiber, as different cord constructions may lead to higher forces, in accordance with IEC 60794-2-50.
Two way socket connector interface
Figure 3 shows the socket connector Figure 4 and Table 3 show the two way socket connector interface
Figure 3 – Two way socket connector (isometric view)
Figure 4 – Two way socket connector mating dimensions
Table 3 – Two way socket connector dimensions
Dimension N represents the finished plug endface after polishing, as shown in Table 6 The spring-loaded ferrule is adjustable under axial compression, making dimension N variable The required ferrule compression force should range from 5.0 N to 6.0 N when dimension N is set between 3.5 mm and 3.7 mm It is important to note that these forces apply only to buffered fiber, as different cord constructions may lead to higher forces, according to IEC 60794-2-50.
Four way plug connector interface 1 1
The plug connector is illustrated in Figure 5, while Figure 6 and Table 4 detail the four-way plug connector interface It features a resilient split alignment sleeve that accommodates a pin gauge at its center with a force ranging from 1.0 N to 2.5 N, provided the plug ferrule is inserted from the opposite side until both the pin gauge and plug ferrule make contact The nominal size of the pin gauge is 1.2490 mm, as specified in Table 8.
Figure 5 – Four way plug connector (isometric view)
Figure 6 – Four way plug connector mating dimensions
Optical reference plane Mechanical reference plane
Table 4 – Four way plug connector dimensions
The P cross section measures 1 mm with a tolerance of 70 ± 1 0 Shore A for the basic dimension M, which represents the finished ferrule endface after polishing The spring-loaded ferrule is designed to move under axial compression, making dimension M variable When adjusting the optical datum target, dimension M should be set between 3.5 mm and 3.7 mm, with the ferrule compression force required to be between 5.0 N and 6.0 N It is important to note that these force specifications apply to buffered fiber only, as different cord constructions may lead to higher forces, in accordance with IEC 60794-2-50.
Four way socket connector interface 1 3
Figure 7 shows the socket connector Figure 8 and Table 5 show the four way socket connector interface
Figure 7 – Four way socket connector (isometric view)
Figure 8 – Four way socket connector mating dimensions
Table 5 – Four way socket connector dimensions
Dimension M represents the finished plug endface after polishing, as shown in Table 6 The ferrule can move under a specific axial compressing force, making dimension M variable The required ferrule compression force ranges from 5.0 N to 6.0 N when the optical datum target, dimension M, is adjusted to between 3.5 mm and 3.7 mm It is important to note that these forces apply only to buffered fiber, as different cord constructions may lead to higher forces, according to IEC 60794-2-50.
The IEC 61 754-31 series specifies plugs and sockets featuring ferrules with a spherically polished endface that ensure physical contact (PC), as illustrated in Figure 9 and detailed in Table 6 The dimensional requirements pertain to the finished ferrule following the completion of all polishing processes.
NOTE The drawing is not to scale
Figure 9 – PC endface geometry (expanded view)
BH a – 1 ,0 a Chamfer or radius is allowed to a maximum depth of 0,5 mm from the ferrule endface
Refer to the IEC 61 755-3 series for information on the endface geometry requirements of the
The ferrule is made from zirconia ceramic, although other materials with compatible properties can be utilized However, it is essential that these alternative materials meet the endface performance requirements under all conditions.
9 Pin gauge for plug connector
Figure 1 0 shows the pin gauge for the plug connector Table 8 shows the pin gauge dimensions
Figure 1 0 – Pin gauge for plug connector
CK diameter mm CN mm Remarks
1 ,248 8 1 ,249 2 4,2 1 5 a a Surface roughness along CN should be < 0,2 à m Ra; cylindricity is less than 0, 5 à m
IEC 60794-2-50, Optical fibre cables – Part 2-50: Indoor cables – Family specification for simplex and duplex cables for use in terminated cable assemblies
5 Interface de connecteur à deux voies 25
5.1 Interface de connecteur mâle à deux voies 25
5.2 Interface de connecteur femelle à deux voies 27
6 Interface de connecteur à quatre voies 29
6.1 Interface de connecteur mâle à quatre voies 29
6.2 Interface de connecteur femelle à quatre voies 31
9 Broche calibrée pour le connecteur mâle 34
Figure 1 – Connecteur mâle à deux voies (vue isométrique) 25
Figure 2 – Dimensions d’accouplement du connecteur mâle à deux voies 26
Figure 3 – Connecteur femelle à deux voies (vue isométrique) 27
Figure 4 – Dimensions d’accouplement du connecteur femelle à deux voies 28
Figure 5 – Connecteur mâle à quatre voies (vue isométrique) 30
Figure 6 – Dimensions d’accouplement du connecteur mâle à quatre voies 30
Figure 7 – Connecteur femelle à quatre voies (vue isométrique) 31
Figure 8 – Dimensions d’accouplement du connecteur femelle à quatre voies 32
Figure 9 – Géométrie de l’extrémité PC (vue agrandie) 33
Figure 1 0 – Broche calibrée pour le connecteur mâle 34
Tableau 1 – Compatibilité d’accouplement entre les fiches et les prises femelles dans la série d'interfaces IEC 61 754-31 25
Tableau 2 – Dimensions du connecteur mâle à deux voies 27
Tableau 3 – Dimensions du connecteur femelle à deux voies 29
Tableau 4 – Dimensions du connecteur mâle à quatre voies 31
Tableau 5 – Dimensions du connecteur femelle à quatre voies 33
Tableau 8 – Dimensions de la broche calibrée 35
DISPOSITIFS D’INTERCONNEXION ET COMPOSANTS PASSIFS À FIBRES OPTIQUES – INTERFACES DE CONNECTEURS À FIBRES OPTIQUES – Partie 31 : Famille de connecteurs de type N-FO
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La Norme internationale IEC 61 754-31 a été établie par le sous-comité 86B: Dispositifs d'interconnexion et composants passifs à fibres optiques, du comité d'études 86 de l’IEC: Fibres optiques
Le texte de cette norme est issu des documents suivants:
Le rapport de vote indiqué dans le tableau ci-dessus donne toute information sur le vote ayant abouti à l'approbation de cette norme
Cette publication a été rédigée selon les Directives ISO/IEC, Partie 2
A comprehensive list of all parts of the IEC 61754 series, published under the general title "Interconnection Devices and Passive Optical Fiber Components – Optical Fiber Connector Interfaces," is available on the IEC website.
The committee has determined that the content of this publication will remain unchanged until the stability date specified on the IEC website at "http://webstore.iec.ch" regarding the relevant publication data On that date, the publication will be updated.
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Généralités
The N-FO connector family features a range of male and female circular connectors with two and four pins Each male connector is equipped with a threaded coupling nut secured by a spring, while the plug's shell is designed with a single keying groove for proper orientation with a key installed in the corresponding female socket The connectors utilize polished 1.25 mm ferrules, which are aligned using elastic sleeves housed within the plug.
Système à deux voies
Ce système comprend deux férules maintenues par ressort dans chaque corps de connecteur Le pas nominal entre les deux centres des fibres est de 3,0 mm
Il dispose d’un mộcanisme de couplage filetộ conỗu pour ờtre serrộ à un couple de 1 Nm à
Système à quatre voies
Ce système comprend quatre férules maintenues par ressort dans une rangée dans chaque corps de connecteur Le pas nominal entre deux centres adjacents des fibres est de 2,50 mm
Il dispose d’un mộcanisme de couplage filetộ conỗu pour ờtre serrộ à un couple de 1 Nm à
Les exigences générales définies dans l’IEC 61 754-1 sont valables pour la présente norme
La présente norme contient les interfaces normalisées suivantes:
Interface IEC 61 754-31 -1 : interface de connecteur mâle à deux voies
Interface IEC 61 754-31 -2: interface de prise femelle à deux voies
Interface IEC 61 754-31 -3: interface de connecteur mâle à quatre voies
Interface IEC 61 754-31 -4: interface de prise femelle à quatre voies
Les fiches et les prises femelles suivantes qui figurent dans le Tableau 1 sont accouplables
Tableau 1 – Compatibilité d’accouplement entre les fiches et les prises femelles dans la série d'interfaces IEC 61 754-31
Interfaces de fiche Interfaces de prise femelle
5 Interface de connecteur à deux voies
Interface de connecteur mâle à deux voies
Figure 1 illustrates the male connector, while Figure 2 and Table 2 detail the two-way male connector interface The alignment mechanism of the connector features a split elastic alignment sleeve This mechanism must accommodate a calibrated pin at its center, requiring a force between 1.0 N and 2.5 N, provided that the plug ferrule is inserted from the opposite side until the calibrated pin and the plug ferrule meet The nominal length of the calibrated pin should be 1.2490 mm (refer to Table 8).
Figure 1 – Connecteur mâle à deux voies (vue isométrique)
Figure 2 – Dimensions d’accouplement du connecteur mâle à deux voies
Plan de référence optique Plan de référence mécanique
Tableau 2 – Dimensions du connecteur mâle à deux voies
The dimension N, measured at 34 to 50.55 ± 5 Shore A, is specified for a polished end of the ferrule The ferrule, held by a spring, can be adjusted through the application of axial compression, making dimension N variable The compression force on the ferrule should range between 5.0 N and 6.0 N when the optical reference target, dimension N, falls within 3.5 mm to 3.7 mm These forces apply only to fibers under protective coating, as different cord constructions may result in higher forces, as referenced in IEC 60794-2-50.
Interface de connecteur femelle à deux voies
La Figure 3 représente le connecteur femelle La Figure 4 et le Tableau 3 présentent l’interface de connecteur femelle à deux voies
Figure 3 – Connecteur femelle à deux voies (vue isométrique)
Figure 4 – Dimensions d’accouplement du connecteur femelle à deux voies
Tableau 3 – Dimensions du connecteur femelle à deux voies
Table 6 indicates that dimension N is specified for a fully polished connector end The ferrule, held by a spring, can be adjusted by applying axial compressive force, making dimension N variable The compressive force on the ferrule should range between 5.0 N and 6.0 N when the optical reference target, dimension N, falls within 3.5 mm to 3.7 mm These forces apply only to fibers under protective coating, as different cord constructions may result in higher forces, as referenced in IEC 60794-2-50.
6 Interface de connecteur à quatre voies
Interface de connecteur mâle à quatre voies
Figure 5 illustrates the male connector, while Figure 6 and Table 4 detail the four-way male connector interface The alignment mechanism of the connector features a split elastic alignment sleeve This mechanism must accommodate a calibrated pin at its center, requiring a force between 1.0 N and 2.5 N, provided that the pin's ferrule is inserted from the opposite side until the calibrated pin and the ferrule meet The nominal length of the calibrated pin should be 1.249.
Figure 5 – Connecteur mâle à quatre voies (vue isométrique)
Figure 6 – Dimensions d’accouplement du connecteur mâle à quatre voies
Plan de référence optique Plan de référence mécanique
Tableau 4 – Dimensions du connecteur mâle à quatre voies
The base dimension P is specified as 1 mm / 70 ± 10 Shore A, while dimension M refers to the finished end of a ferrule after polishing The ferrule, held by a spring, can be adjusted through the application of axial compression, making dimension M variable The compression force on the ferrule should range between 5.0 N and 6.0 N when the optical reference target, dimension M, falls within 3.5 mm to 3.7 mm These forces apply only to fibers under protective coating, as different cord constructions may result in higher forces, as outlined in IEC 60794-2-50.
Interface de connecteur femelle à quatre voies
La Figure 7 représente le connecteur femelle La Figure 8 et le Tableau 5 présentent l’interface de connecteur femelle à quatre voies
Figure 7 – Connecteur femelle à quatre voies (vue isométrique)
Figure 8 – Dimensions d’accouplement du connecteur femelle à quatre voies
Tableau 5 – Dimensions du connecteur femelle à quatre voies
Table 6 indicates that dimension M is specified for a fully polished connector end The ferrule can be adjusted by applying a certain axial compressive force, resulting in a variable dimension M due to direct contact at the ends The required compressive force for the ferrule should be between 5.0 N and 6.0 N when the optical reference target, dimension M, falls within the range of 3.5 mm to 3.7 mm These forces apply only to fibers with protective coatings, as different cord constructions may result in higher forces, as referenced in IEC 60794-2-50.
The female connectors and sockets specified in the IEC 61 754-31 series feature ferrules with a spherically polished end, ensuring physical contact (PC), as illustrated in Figure 9 and detailed in Table 6 The dimensional requirements apply to the finished ferrule after all polishing procedures have been completed.
NOTE Le dessin n’est pas à l’échelle
Figure 9 – Géométrie de l’extrémité PC (vue agrandie)
BH a – 1 ,0 a Il est admis de pratiquer un chanfrein ou rayon jusqu’à une profondeur maximale de 0,5 mm depuis l’extrémité de la férule
Voir la série IEC 61 755-3 pour les informations concernant les exigences de géométrie d’extrémité de l’interface PC
The post is made of zirconia ceramic, although other materials may be used if they possess properties compatible with zirconia However, it is essential that the performance requirements are met under all conditions.
9 Broche calibrée pour le connecteur mâle
La Figure 1 0 représente la broche calibrée pour le connecteur mâle Le Tableau 8 présente les dimensions de la broche calibrée
Figure 1 0 – Broche calibrée pour le connecteur mâle
Tableau 8 – Dimensions de la broche calibrée
Diamètre CK mm CN mm Remarques
1 ,248 8 1 ,249 2 4,2 1 5 a a Il convient que la rugositộ de surface le long de CN soit < 0,2 à m Ra; la cylindricitộ est infộrieure à 0,5 à m
IEC 60794-2-50, Câbles à fibres optiques – Partie 2-50: Câbles intérieurs – Spécification de famille pour les câbles simplex et duplex utilisés dans les ensembles de câbles équipés