IEC 61754-27:2013

Fibre optic interconnecting devices and passive components - Fibre optic connector interfaces - Part 27: Type M12-FO connector family

IEC 61754-27:2013 defines the standard interface dimensions for the type M12-FO family of connectors. This connector is of duplex plug/adaptor/plug configuration and designed for industrial environment as described in ISO/IEC/TR 29106, severity class M3 and I3. Multiple designs for machines and equipment require solutions with different fibre types. Keywords: standard interface dimensions for the type M12-FO family of connectors

Dispositifs d'interconnexion et composants passifs à fibres optiques - Interfaces de connecteurs pour fibres optiques - Partie 27: Famille de connecteurs de type M12-FO

La CEI 61754-27:2013 définit les dimensions des interfaces normalisées pour la famille de connecteurs de type M12-FO. Ce connecteur a une configuration fiche/raccord/fiche duplex, et il est conçu pour des environnements industriels tels qu'ils sont décrits dans la l'ISO/CEI/TR 29106, classes de sévérité M3 et I3. Les différentes conceptions pour les machines et les équipements exigent des solutions avec différents types de fibres. Mots clés: dimensions des interfaces normalisées pour la famille de connecteurs de type M12-FO

General Information

• Status: Published
• Publication Date: 15-May-2013
• ICS: 33.180.20 - Fibre optic interconnecting devices
• Technical Committee: SC 86B - Fibre optic interconnecting devices and passive components
• Current Stage: PPUB - Publication issued
• Start Date: 16-May-2013
• Completion Date: 15-Jun-2013

Overview

IEC 61754-27:2013 is an international standard that defines the standard interface dimensions for the M12-FO family of fibre optic connectors. These connectors feature a duplex plug/adaptor/plug configuration and are specifically engineered for industrial environments in compliance with ISO/IEC TR 29106, severity classes M3 and I3. The standard addresses the mechanical and optical interface specifications to ensure reliable connectivity and interchangeability for diverse fibre types used in industrial applications.

The M12-FO connectors are characterized by a 2.5 mm nominal ferrule diameter, a circular design with a screw-locking M12 thread, and robust protection rated IP65 and IP67 according to IEC 60529. This standard provides critical specifications that facilitate consistent manufacturing and deployment of these connectors in harsh industrial environments, where durability and precision are paramount.

Key Topics

• Connector Configuration: Duplex plug/adaptor/plug system suitable for industrial use.
• Mechanical Interface: Defined dimensions for plug connectors, adaptors, and active device interfaces ensuring compatibility and standardized mating.
• Optical Fibres Supported: Designed to accommodate multiple fibre categories including single-mode (B1.1, B1.3) and multimode fibres (A3c, A3d, A4a, A4d) as per IEC 60793 series.
• Protection and Durability: Connector housings comply with IP65 and IP67 protection ratings suitable for severe industrial conditions.
• Mating and Alignment: Spring-loaded coupling mechanism with four keys to ensure precise mating orientation; alignment done via resilient sleeve or rigid bore design.
• Intermatability Table: Clearly defined interoperability between different plug connector interfaces, adaptors, and active device interfaces.

Applications

IEC 61754-27:2013 caters predominantly to industrial automation, process control, and instrumentation environments where fiber optic communication must withstand mechanical stress, vibration, and exposure to dust or moisture. Applications include:

• Factory Automation: Reliable fibre optic connections for sensors, controllers, and machine communication systems.
• Industrial Measurement: Signal transmission in harsh environments requiring robust and standardized optical connectors.
• Process Control Networks: Integration into industrial Ethernet and fieldbus systems with high requirements for connection integrity and durability.
• Equipment Manufacturing: Facilitating modular design with compatible connectors for diverse industrial equipment and machinery.

The robustness and standardization outlined in IEC 61754-27 make the M12-FO connector family ideal for industrial systems requiring dependable optical communication and interconnectivity.

Related Standards

• IEC 60529 – Degrees of protection provided by enclosures (IP Code), essential for testing environmental protection levels of connectors.
• IEC 60793 Series – Specifications for optical fibres, providing fiber categories compatible with the M12-FO connectors.
• IEC 61076-2-101 – Detailing M12 connectors with screw-locking mechanisms used for both electrical and optical applications.
• IEC 61755 Series – Standards on fibre optic connector optical interfaces relevant to fiber polishing and endface geometry.
• ISO/IEC TR 29106 – Environmental classification (MICE) guiding industrial severity conditions relevant to connector design.

Summary

IEC 61754-27:2013 establishes crucial dimensional and interface requirements for the M12-FO fibre optic connectors, enabling high-performance duplex fiber optic connectivity in industrial settings. Its emphasis on durability, precise optical alignment, and protection against environmental factors supports the growing demand for robust fibre optic infrastructure in industrial automation and control systems. Manufacturers and system integrators rely on this standard to ensure interoperability, ease of installation, and maintenance of high-quality optical networks in challenging operational environments.

Standards Content (Sample)

IEC 61754-27 ®
Edition 1.0 2013-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Fibre optic interconnecting devices and passive components – Fibre optic
connector interfaces –
Part 27: Type M12-FO connector family

Dispositifs d’interconnexion et composants passifs à fibres optiques –
Interfaces de connecteurs pour fibres optiques –
Partie 27: Famille de connecteurs de type M12-FO
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IEC 61754-27 ®
Edition 1.0 2013-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Fibre optic interconnecting devices and passive components – Fibre optic

connector interfaces –
Part 27: Type M12-FO connector family

Dispositifs d’interconnexion et composants passifs à fibres optiques –

Interfaces de connecteurs pour fibres optiques –

Partie 27: Famille de connecteurs de type M12-FO

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX N
ICS 33.180.20 ISBN 978-2-83220-809-0

– 2 – 61754-27 © IEC:2013
CONTENTS
FOREWORD . 3
1 Scope . 5
2 Normative references . 5
3 Description . 5
4 Interfaces . 6
4.1 General . 6
4.2 Part 27-1 plug connector interface for category B1.1 or B1.3 fibres . 6
4.3 Part 27-2 plug connector interface for category A3c or A3d fibres . 8
4.4 Part 27-3 plug connector interface for category A4a or A4d fibres . 10
4.5 Part 27-4 adaptor connector interface . 12
4.6 Part 27-5 active device interface . 13
Bibliography . 15

Figure 1 – Plug connector interface PC . 7
Figure 2 – Detail of spherically polished ferrule PC endface . 8
Figure 3 – Plug connector interface for category A3c or A3d fibres . 9
Figure 4 – Detail of polished ferrule endface for category A3c or A3d fibres . 10
Figure 5 – Plug connector interface for category A4a or A4d fibres . 11
Figure 6 – Detail of polished ferrule endface for category A4a or A4d fibres . 12
Figure 7 – Adaptor connector interface . 13
Figure 8 – Active device interface . 14

Table 1 – Interfaces . 6
Table 2 – Intermatability . 6
Table 3 – Dimensions for the details in Figure 1. 7
Table 4 – Dimensions for the details in Figure 2. 8
Table 5 – Ferrule grades . 8
Table 6 – Dimensions of plug connector interface for category A3c or A3d fibres . 9
Table 7 – Dimensions for the details in Figure 4. 10
Table 8 – Ferrule grades . 10
Table 9 – Dimensions of plug connector interface for category A4a or A4d fibres . 11
Table 10 – Dimensions for the details in Figure 6 . 12
Table 11 – Ferrule grades . 12
Table 12 – Dimensions of adaptor connector interface . 13
Table 13 – Dimensions of active device interface . 14

61754-27 © IEC:2013 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
FIBRE OPTIC INTERCONNECTING DEVICES
AND PASSIVE COMPONENTS –
FIBRE OPTIC CONNECTOR INTERFACES –

Part 27: Type M12-FO connector family

FOREWORD
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patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61754-27 has been prepared by subcommittee 86B: Fibre optic
interconnecting devices and passive components, of IEC technical committee 86: Fibre optics.
The text of this standard is based on the following documents:
FDIS Report on voting
86B/3597/FDIS 86B/3626/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.

– 4 – 61754-27 © IEC:2013
A list of all parts of the IEC 61754 series, published under the general title, Fibre optic
interconnecting and passive components – Fibre optic connector interfaces, can be found on
the IEC website.
Future standards in this series will carry the new general title as cited above. Titles of existing
standards in this series will be updated at the time of the next edition.
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.
61754-27 © IEC:2013 – 5 –
FIBRE OPTIC INTERCONNECTING DEVICES
AND PASSIVE COMPONENTS –
FIBRE OPTIC CONNECTOR INTERFACES –

Part 27: Type M12-FO connector family

1 Scope
This part of IEC 61754 defines the standard interface dimensions for the type M12-FO family
of connectors.
This connector is of duplex plug/adaptor/plug configuration and designed for industrial
environment as described in ISO/IEC TR 29106, severity class M and I . Multiple designs for
3 3
machines and equipment require solutions with different fibre types.
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 60529, Degrees of protection provided by enclosures (IP Code)
IEC 60793-2-30, Optical fibres – Part 2-30: Product specifications – Sectional specification for
category A3 multimode fibres
IEC 60793-2-40, Optical fibres – Part 2-40: Product specifications – Sectional specification for
category A4 multimode fibres
IEC 60793-2-50, Optical fibres – Part 2-50: Product specifications – Sectional specification for
class B single-mode fibres
IEC 61076-2-101, Connectors for electronic equipment – Product requirements – Part 2-101:
Circular connectors – Detail specification for M12 connectors with screw-locking
IEC 61755-3 (all parts 3), Fibre optic connector optical interfaces – Part 3: Optical interface
ISO/IEC TR 29106, Information technology – Generic cabling – Introduction to the MICE
environmental classification
3 Description
The M12-FO connector family is a duplex plug connector set of plug/adaptor configuration
which is characterized by a 2,5 mm nominal ferrule diameter and can be used for fibres as
described in Table 1.
This circular connector includes a housing with a M12-thread screw locking mechanism and a
protection according to IEC 60529, IP 65 and IP 67. Electrical M12-connectors are typically
used for industrial process, measurement and control. They are described and dimensioned in
IEC 61076-2-101 and additional information for the optical connector is given in this standard.

– 6 – 61754-27 © IEC:2013
The coupling mechanism is spring loaded relative to the ferrules in the direction of the optical
axes. The ferrules stand back from the front face in the unmated condition due to a shroud to
shelter them from mechanical impact during handling and the mating process.
The plug and adaptor are equipped with four keys to define the mating orientation of the
duplex connector. The optical alignment mechanism of the adaptor is from a resilient sleeve
style. The alignment mechanism for the active device interface can be a rigid bore or a
resilient sleeve.
4 Interfaces
4.1 General
This standard contains the interfaces for the type M12-FO connector family as described in
Table 1. The interfaces are intermatable according to Table 2.
Table 1 – Interfaces
Interface Title
Plug connector interface with spherical polished endface (PC) for IEC 60793-2-50 category
27-1
B1.1 or B1.3 fibres.
27-2 Plug connector interface for IEC 60793-2-30 category A3c or A3d fibres.
27-3 Plug connector interface for IEC 60793-2-40 category A4a or A4d fibres.
27-4 Adaptor connector interface
27-5 Active device interface
NOTE A plug connector interface with angled polished endface (APC) 8° is not described.

Table 2 – Intermatability
M12-FO IEC 61754-27 Adaptor Active device
connector family interface 27-4 27-5
27-1 Mate Mate
Plug 27-2 Mate Mate
27-3 Mate Mate
4.2 Part 27-1 plug connector interface for category B1.1 or B1.3 fibres
The M12-FO plug connector interface with spherical polished endface (PC 0°, SM fibre) is
described in Figures 1 and 2 and Tables 3 to 5. All dimensions are under mated conditions.

61754-27 © IEC:2013 – 7 –
O
Optical reference plane
IEC  1196/13
Figure 1 – Plug connector interface PC
Table 3 – Dimensions for the details in Figure 1
Dimensions
mm
Reference Remarks
Minimum Nominal Maximum
a
A 1,0 1,3 Dimensions in
unmated condition
B 7,0 7,5
C 8,0 8,2
D 4,95 5,05
E 8,8 9,0
F 60°
G 90°
H R0,4 R0,5
I 2,497 2,4 995
K 9,6 9,8
L 10,3 10,8
M 0,8 1,0
N M12
O 10
a
Ferrule compression force shall be from 7,8 N to 11,8 N when the ferrule is compressed to a point where A is
0,50 mm ± 0,10 mm.
– 8 – 61754-27 © IEC:2013
L
IEC  1197/13
Figure 2 – Detail of spherically polished ferrule PC endface
Table 4 – Dimensions for the details in Figure 2
Dimensions
mm
Reference Remarks
Minimum Maximum
a
J 0,8 N/A Diameter
b
K N/A 1,8
c
L 5 30 Radius
a
Maximum value for J is not defined in the IEC 61755-3 series.
b
Minimum value for K is not defined in the IEC 61755-3 series.
c
Dome eccentricity of the spherical polished endface shall be less than 70 µm.
N/A = not applicable.
Table 5 – Ferrule grades
Dimensions outer diameter
mm
Precision grade level Remarks
Minimum Maximum
1 2,4 985 2,4 995
2 2,4 980 2,4 995
3 2,4 970 2,4 995
4.3 Part 27-2 plug connector interface for category A3c or A3d fibres
The M12-FO plug connector interface for category A3c or A3d fibres are described in
Figures 3 and 4 and Tables 6 to 8. All dimensions are under mated conditions.

61754-27 © IEC:2013 – 9 –
O
Optical reference plane
IEC  1198/13
or A3d fibres
Figure 3 – Plug connector interface for category A3c
Table 6 – Dimensions of plug connector interface for category A3c or A3d fibres
Dimensions
mm
Reference Remarks
Minimum Nominal Maximum
a
A 1,0 1,3 Dimensions in
unmated condition
B 7,0 7,5
C 8,0 8,2
D 4,95 5,05
E 8,8 9,0
F 60°
G 90°
H R0,4 R0,5
I 2,497 2,4 995
K 9,6 9,8
L 10,3 10,8
M 0,8 1,0
N M12
O 10
a
Ferrule compression force shall be from 7,8 N to 11,8 N when the ferrule is compressed to a point where A is
0,50 mm ± 0,10 mm.
– 10 – 61754-27 © IEC:2013
IEC  1197/13
Figure 4 – Detail of polished ferrule endface for category A3c or A3d fibres
Table 7 – Dimensions for the details in Figure 4
Dimensions
mm
Reference Remarks
Minimum Maximum
a e
J 0,8 N/A Diameter
b e
K N/A 1,8
c
L 5 30 Radius
a
Maximum value for J is not defined in the IEC 61755-3 series.
b
Minimum value for K is not defined in the IEC 61755-3 series.
c
Dome eccentricity of the spherical polished endface shall be less than 70 µm.
d
N/A: not applicable.
Table 8 – Ferrule grades
Dimensions outer diameter
mm
Precision grade level Remarks
Minimum Maximum
2,470 0 2,499 5 Note
NOTE An OI for category A3c or A3d fibres is not yet defined in the IEC 61755 series.

4.4 Part 27-3 plug connector interface for category A4a or A4d fibres
The M12-FO plug connector interface for category A4a or A4d fibres is described in Figure 5
and 6 and Table 9 to 11. All dimensions are under mated conditions.

61754-27 © IEC:2013 – 11 –
O
Optical reference plane
IEC  1199/13
Figure 5 – Plug connector interface for category A4a or A4d fibres
Table 9 – Dimensions of plug connector interface for category A4a or A4d fibres
Dimensions
mm
Reference Remarks
Minimum Nominal Maximum
a
A 1,0 1,3 Dimensions in
unmated condition
B 7,0 7,5
C 8,0 8,2
D 4,95 5,05
E 8,8 9,0
F 60°
G 90°
H R0,4 R0,5
I 2,48 2,4 995
K 9,6 9,8
L 10,3 10,8
M 0,8 1,0
N M12 M12
O 10
a
Ferrule compression force shall be from 7,8 N to 11,8 N when the ferrule is compressed to a point where A is
0,50 mm ± 0,10 mm.
– 12 – 61754-27 © IEC:2013
IEC  1200/13
Figure 6 – Detail of polished ferrule endface for category A4a or A4d fibres
Table 10 – Dimensions for the details in Figure 6
Dimensions
mm
Reference Remarks
Minimum Maximum
A 1,8 2,0 Diameter
B 0,5 0,3
C 0,03 –0,03
NOTE An OI for category A4a or A4d fibres is not yet defined in the IEC 61755 series.

Table 11 – Ferrule grades
Dimensions outer diameter
mm
Precision grade level Remarks
Minimum Maximum
2,4 700 2,4 995 Note
NOTE An OI for category A4a or A4d fibres is not yet defined in the IEC 61755 series.

4.5 Part 27-4 adaptor connector interface
The M12-FO adaptor connector interface is described in Figure 7 and Table 12. All
dimensions are under mated conditions.

61754-27 © IEC:2013 – 13 –
IEC  1201/13
Fig
...