IEC 61754-6:2022

IEC 61754-6 ®
Edition 3.1 2026-10
INTERNATIONAL
STANDARD
CONSOLIDATED VERSION
Fibre optic interconnecting devices and passive components - Fibre optic
connector interfaces -
Part 6: Type MU connector family
ICS 33.180.20 ISBN 978-2-8327-1567-3
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CONTENTS
FOREWORD . 4
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Description . 6
5 Interfaces . 7
Annex A (informative) Configuration of type MU-A connector set . 77
Annex B (informative) Configuration of type MU-B connector set . 78
Annex C (informative) Floating 2-port connector plug . 79
Annex D (informative) Panel dimensions . 80
D.1 General . 80
D.2 Simplex adaptor . 80
D.3 4,5 mm duplex adaptor . 80
D.4 6,25 mm duplex adaptor . 81
D.5 Horizontal duplex adaptor . 81
D.6 4,5 mm 8-port adaptor . 82
Bibliography . 83

Figure 1 – Simplex plug connector interface – Push/pull . 10
Figure 2 – 4,5 mm duplex plug connector interface – Push/pull . 13
Figure 3 – Simplex adaptor connector interface – Push/pull . 16
Figure 4 – Pin gauge for resilient alignment sleeve . 18
Figure 5 – 4,5 mm duplex adaptor connector interface – Push/pull . 19
Figure 6 – 8-port adaptor connector interface – Push/pull . 22
Figure 7 – Plug connector interface – For printed board housings . 24
Figure 8 – Sleeve holder interface . 27
Figure 9 – 2-port backplane housing interface. 29
Figure 10 – 2-port printed board housing interface . 33
Figure 11 – 8-port backplane housing interface . 37
Figure 12 – 8-port printed board housing interface . 41
Figure 13 – Simplex active device receptacle interface . 45
Figure 14 – Detail of the mechanical stop for rigid bore alignment feature. 47
Figure 15 – 4,5 mm duplex active device receptacle interface . 48
Figure 16 – Detail of the mechanical stop for rigid bore alignment feature. 50
Figure 17 – 6,25 mm duplex active device receptacle interface . 51
Figure 18 – Detail of the mechanical stop for rigid bore alignment feature. 53
Figure 19 – Plug connector interface – For printed board housings, APC . 54
Figure 20 – Simplex plug connector interface – Push/pull, APC . 57
Figure 21 – 4,5 mm duplex plug connector interface – Push/pull, APC . 60
Figure 22 – 6,25 mm duplex plug connector interface – Push/pull, APC . 63
Figure 23 – 6,25 mm duplex plug connector interface – Push/pull . 66
Figure 24 – 6,25 mm duplex adaptor connector interface . 69
Figure 25 – Horizontal duplex plug connector interface – Push/pull . 71
Figure 26 – Horizontal duplex adaptor connector interface . 74
Figure A.1 – Configuration of type MU-A connector set . 77
Figure B.1 – Configuration of type MU-B connector set . 78
Figure C.1 – Floating 2-port connector plug . 79
Figure D.1 – Panel cut out . 80
Figure D.2 – Panel cut out . 80
Figure D.3 – Panel cut out . 81
Figure D.4 – Panel cut out . 81
Figure D.5 – Panel cut out . 82

Table 1 – Interfaces . 7
Table 2 – Intermateability of MU-A connectors . 8
Table 3 – Intermateability of MU-B connectors . 8
Table 4 – Intermateability of MU receptacles . 9
Table 5 – Dimensions of the simplex plug connector interface . 11
Table 6 – Grade of the simplex plug connector . 12
Table 7 – Dimensions of the 4,5 mm duplex plug connector interface . 14
Table 8 – Grade of the 4,5 mm duplex plug connector . 15
Table 9 – Dimensions of the simplex adaptor connector interface . 17
Table 10 – Grade of the simplex adaptor connector . 18
Table 11 – Pin gauge dimensions . 18
Table 12 – Dimensions of the 4,5 mm duplex adaptor connector interface . 20
Table 13 – Grade of the 4,5 mm duplex adaptor connector . 21
Table 14 – Dimensions of the 8-port adaptor connector interface . 23
Table 15 – Grade of the 8-port adaptor connector . 24
Table 16 – Dimensions of the plug connector interface . 25
Table 17 – Grade of the plug connector . 26
Table 18 – Dimensions of the sleeve holder interface . 28
Table 19 – Grade of the sleeve holder . 28
Table 20 – Dimensions of the 2-port backplane housing interface . 31
Table 21 – Grade of the 2-port backplane housing . 32
Table 22 – Dimensions of the 2-port printed board housing interface . 35
Table 23 – Dimensions of the 8-port backplane housing interface . 39
Table 24 – Grade of the 8-port backplane housing . 40
Table 25 – Dimensions of the 8-port printed board housing interface . 43
Table 26 – Dimensions of the simplex active device receptacle interface . 46
Table 27 – Alignment feature grade . 47
Table 28 – Dimensions of the mechanical stop for rigid bore alignment feature . 47
Table 29 – Mechanical stop feature grade. 48
Table 30 – Dimensions of the 4,5 mm duplex active device receptacle interface . 49
Table 31 – Alignment feature grade . 50
Table 32 – Dimensions of the mechanical stop for rigid bore alignment feature . 50
Table 33 – Mechanical stop feature grade. 51
Table 34 – Dimensions of the 6,25 mm duplex active device receptacle interface . 52
Table 35 – Alignment feature grade . 53
Table 36 – Dimensions of the mechanical stop for rigid bore alignment feature . 53
Table 37 – Mechanical stop feature grade. 54
Table 38 – Dimensions of the plug connector interface – For printed board housings, APC . 55
Table 39 – Dimensions of the simplex plug connector interfaces, APC . 58
Table 40 – Dimensions of the 4,5 mm duplex plug connector interfaces, APC . 61
Table 41 – Dimensions of the 6,25 mm duplex plug connector interface, APC. 64
Table 42 – Dimensions of the 6,25 mm duplex plug connector interface . 66
Table 43 – Grade of the 6,25 mm duplex plug connector. 68
Table 44 – Dimensions of the 6,25 mm duplex adaptor connector interface . 69
Table 45 – Grade of the 6,25 mm duplex adaptor connector . 70
Table 46 – Dimensions of the horizontal duplex plug connector interface . 72
Table 47 – Grade of the horizontal duplex plug connector . 73
Table 48 – Dimensions of the horizontal duplex adaptor connector interface . 75
Table 49 – Grade of the horizontal duplex adaptor connector . 76
Table C.1 – Dimensions table for 2-port connector plug . 79
Table D.1 – Dimensions for simplex adaptor . 80
Table D.2 – Dimensions for 4,5 mm duplex adaptor . 81
Table D.3 – Dimensions for 6,25 mm duplex adaptor . 81
Table D.4 – Dimensions for horizontal duplex adaptor . 82
Table D.5 – Dimensions for 4,5 mm 8-port adaptor . 82

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
Fibre optic interconnecting devices and passive components -
Fibre optic connector interfaces -
Part 6: Type MU connector family

FOREWORD
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This consolidated version of the official IEC Standard and its amendment has been prepared
for user convenience.
IEC 61754-6 edition 3.1 contains the third edition (2022-02) [documents 86B/4562/FDIS and
86B/4585/RVD] and its amendment 1 (2026-10) [documents 86B/5267/FDIS and
86B/5290/RVD].
In this Redline version, a vertical line in the margin shows where the technical content is
modified by amendment 1. Additions are in green text, deletions are in strikethrough red text.
A separate Final version with all changes accepted is available in this publication.

IEC 61754-6 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 2013 and constitutes a
technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) the test method IEC 61300-3-22 for the compression force of the ferrule was added;
b) Annex D (informative) with cut out dimension requirements for testing the strength of
mounted adaptors was added.
The text of this International Standard is based on the following documents:
Draft Report on voting
86B/4562/FDIS 86B/4585/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 of the IEC 61754 series, under the general title Fibre optic interconnecting
devices 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 document and its amendment 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, or
– revised.
1 Scope
This part of IEC 61754 specifies the standard interface dimensions for type MU family of
connectors.
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 61300-3-22, Fibre optic interconnecting devices and passive components – Basic test and
measurement procedures – Part 3-22: Examinations and measurements – Ferrule compression
force
IEC 61754-1, Fibre optic interconnecting devices and passive components – Fibre optic
connector interfaces – Part 1: General and guidance
IEC 61755-3 (all parts), Fibre optic interconnecting devices and passive components -
Connector optical interfaces: Connector parameters of dispersion unshifted single-mode
physically contacting fibres
IEC 61755-3-2, Fibre optic interconnecting devices and passive components - Connector
optical interfaces - Part 3-2: Connector parameters of dispersion unshifted single-mode
physically contacting fibres - Angled 2,5 mm and 1,25 mm diameter cylindrical full zirconia
ferrules
IEC 63267-3 (all parts), Fibre optic interconnecting devices and passive components -
Connector optical interfaces for enhanced macro bend multimode fibres: Connector parameters
of physically contacting 50 µm core diameter fibres
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 61754-1 apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
4 Description
The parent connector for type MU connector family is a miniature single-position plug which is
characterized by a cylindrical, spring-loaded butting ferrule(s) of a 1,25 mm typical diameter,
and a push-pull coupling mechanism. The optical alignment mechanism of the connectors is of
a rigid hole or a resilient sleeve style.
This document type MU connector family defines the standard interface dimensions of active
device receptacles for the type MU connectors. The receptacles are used to retain the connector
plugs and mechanically maintain the optical datum target of the plugs at a defined position
within the receptacle housings.
5 Interfaces
This document contains the standard interfaces showed in Table 1.
Table 1 – Interfaces
Interface IEC 61754-6-1 Simplex plug connector interface – Push/pull (see Figure 1)
Interface IEC 61754-6-2 4,5 mm duplex plug connector interface – Push/pull (see Figure 2)
Interface IEC 61754-6-3 Simplex adaptor connector interface – Push/pull (see Figure 3)
Interface IEC 61754-6-4 4,5 mm duplex adaptor connector interface – Push/pull (see Figure 5)
Interface IEC 61754-6-5 8-port adaptor connector interface – Push/pull (see Figure 6)
Interface IEC 61754-6-6 Plug connector interface – for printed board housings (see Figure 7)
Interface IEC 61754-6-7 Sleeve holder interface – for printed board housings (see Figure 8)
Interface IEC 61754-6-8 2-port backplane housing interface – Self-retentive (see Figure 9)
Interface IEC 61754-6-9 2-port printed board housing interface – Self-retentive (see Figure 10)
Interface IEC 61754-6-10 8-port backplane housing interface – Self-retentive (see Figure 11)
Interface IEC 61754-6-1 8-port printed board housing interface – Self-retentive (see Figure 12)
Interface IEC 61754-6-12 Simplex active device receptacle interface – for physical contact (PC) connector
plug (see Figure 13)
Interface IEC 61754-6-13 4,5 mm duplex active device receptacle interface – for PC connector plug
(see Figure 15)
Interface IEC 61754-6-14 6,25 mm duplex active device receptacle interface – for PC connector plug
(see Figure 17)
Interface IEC 61754-6-15 Plug connector interface – for printed board housings, angled PC (APC) 8
degrees (see Figure 19)
Interface IEC 61754-6-16 Simplex plug connector interface – Push/pull, APC 8 degrees (see Figure 20)
Interface IEC 61754-6-17 4,5 mm duplex plug connector interface – Push/pull, APC 8 degrees
(see Figure 21)
Interface IEC 61754-6-18 6,25 mm duplex plug connector interface – Push/pull, APC 8 degrees
(see Figure 22)
Interface IEC 61754-6-19 6,25 mm duplex plug connector interface – Push/pull (see Figure 23)
Interface IEC 61754-6-20 6,25 mm duplex adaptor connector interface – Push/pull (see Figure 24)
Interface IEC 61754-6-21 Horizontal duplex plug connector interface – Push/pull (see Figure 25)
Interface IEC 61754-6-22 Horizontal duplex adaptor connector interface – Push/pull (see Figure 26)

The plugs of interfaces IEC 61754-6-1, IEC 61754-6-2, IEC 61754-6-6, IEC 61754-6-19 and
IEC 61754-6-21 have a ferrule(s) with a spherically polished endface, and realize physical
contact (PC). The plugs of interfaces IEC 61754-6-15, IEC 61754-6-16, IEC 61754-6-17 and
IEC 61754-6-18 have a ferrule(s) with a spherically polished angled endface and realize angled
PC (APC).
The type MU connector family comprises two types of connector set: MU-A connector set
(see Annex A) and MU-B connector set (see Annex B). The MU-A connector set is a
plug/adaptor configuration with a push-pull coupling mechanism. The MU-B connector set is a
plug-in type back-plane connector configuration which is plug/backplane and printed board
housings/plug for printed board housing/sleeve holder configuration and is equipped with a self-
retentive mechanism.
The type MU-A connector set consists of simplex and duplex plugs, and simplex, duplex and
8-port adaptors. The plugs are common to the backplane connector housings of the type MU-B
connector set.
The type MU-B connector set consists of 2-port and 8-port backplane and printed board
connector housings, simplex and duplex plugs, plug for printed board connector housings, and
sleeve holder. The plug for printed board connector housing is used as a jack together with the
sleeve holder. The jack is attached into the printed board connector housing.
Table 2, Table 3 and Table 4 show the intermateablitiy of the standard interfaces. It shall be
noted however that in order to obtain the designated optical performance, any plug shall be
connected to a counterpart plug whose ferrule end is polished to the same condition.
Table 2 – Intermateability of MU-A connectors
Adaptors
Plugs
61754-6-3 61754-6-4 61754-6-5 61754-6-20 61754- 6-22
61754-6-1 Mate Mate Mate Mate Mate
61754-6-2 Not mate Mate Mate Not mate Not mate
61754-6-16 Mate Mate Mate Mate Mate
61754- 6-17 Not mate Mate Mate Not mate Not mate
61754-6-18 Not mate Not mate Not mate Mate Not mate
61754-6-19 Not mate Not mate Not mate Mate Not mate
61754-6-21 Not mate Not mate Not mate Not mate Mate

Table 3 – Intermateability of MU-B connectors
Connector housings
Backplane connector Printed board connector
Plugs
housing housing
61754-6-8 61754-6-10 61754-6-9 61754-6-11
61754-6-1 Mate Mate Not mate Not mate
61754-6-2 Mate Mate Not mate Not mate
61754-6-6 with 61754-6-7 Not mate Not mate Mate Mate
61754-6-15 with 61754- 6-7
Not mate Not mate Mate Mate
61754-6-16 Mate Mate Not mate Not mate
61754-6-17 Mate Mate Not mate Not mate
61754-6-18 Not mate Not mate Not mate Not mate
61754-6-19 Not mate Not mate Not mate Not mate
61754-6-21 Not mate Not mate Not mate Not mate

Table 4 – Intermateability of MU receptacles
Receptacles
Plugs
61754-6-12 61754-6-13 61754-6-14
61754-6-1 Mate Mate Mate
61754-6-2 Not mate Mate Not mate
61754-6-16 Not mate Not mate Not mate
61754-6-17 Not mate Not mate Not mate
61754-6-18 Not mate Not mate Not mate
61754-6-19 Not mate Not mate Mate
61754-6-21 Not mate Not mate Not mate

Figure 1 is an example of a simplex plug connector interface. Table 5 gives dimensions of the
simplex plug connector interface and Table 6 gives the grade of the simplex plug connector
interface.
Figure 1 – Simplex plug connector interface – Push/pull
Table 5 – Dimensions of the simplex plug connector interface
Dimensions
Reference Remarks
Minimum Maximum
a
A See Table 6
B 2,6 mm 2,7 mm
C 4,6 mm 4,8 mm
D 4,65 mm 4,75 mm
E 4,3 mm 4,4 mm
F 3,3 mm 3,4 mm
G Angle, unit in degrees
25° 35°
H
25° 35° Angle, unit in degrees
b
I 6,55 mm –
c
J 4,2 mm 4,5 mm
K 5,5 mm –
L 2,4 mm 2,5 mm
M
1,5 mm –
N 0,6 mm –
O 0,5 mm –
b
P 2,6 mm –
b d
Q 1 mm 1,1 mm
b
R 2,65 mm 2,9 mm
S 5,5 mm 5,6 mm
T
4,3 mm 4,5 mm
U – 3,7 mm
V – 2,4 mm
W
6,5 mm 6,6 mm
AA 4,3 mm 4,4 mm
AB 3,85 mm 3,95 mm
AC 0,7 mm 0,9 mm
AD 0,2 mm – Radius
AE 3 mm –
AF 2,2 mm 2,3 mm
e
EA
32,5° 45°
Angle, unit in degrees
f
EB 5 mm 30 mm
Radius
EC 0,45 mm 0,73 mm Diameter
a
A chamfer or radius is allowed to a maximum depth of 0,5 mm from the ferrule endface.
b
The delatch housing shall be movable to the right or left. Dimensions L, M and V I, P, Q and R
are given when the delatch housing is at the furthest right.
c
Dimension J is given for the plug endface when not mated. The ferrule is movable by a certain
axial compression force with direct contacting endfaces, and therefore dimension J is variable.
Ferrule compression force shall be 5,5 N to 6,5 N when the position of the optical datum target
from the mechanical datum target is moved in the range of 3,9 mm to 4,1 mm. In addition,
dimension J shall become less than 3,25 mm with a relatively large axial compression force. The
compression force shall be measured according to IEC 61300-3-22.
d
Q is to the right of the mechanical datum target when the delatch housing is to the right
(connected state) and to the left of the mechanical datum target when the delatch housing is to
the left (disconnected state).
e
40° to 45° are desirable to minimize debris for backplane connectors.
f
Dome eccentricity of the spherically polished ferrule endface shall be less than 50 µm.

Table 6 – Grade of the simplex plug connector
Dimensions
mm
Grade Remarks
A
Minimum Maximum
a
A See IEC 61755-3-1 Grade not

specified at this time
a
B See IEC 61755-3-1 Shall be as

specified in the IEC 61755-3
series
a
C See IEC 61755-3-1 Shall be as

specified in the IEC 61755-3
series
a
D See IEC 61755-3-1 Shall be as

specified in the IEC 61755-3
series
a b
A Grade not specified at this time

m
a b
B 1,246 7 1,249 5
m
Shall be as specified in the
IEC 63267-3 series
a b
C Grade not specified at this time

m
Shall be as specified in the
IEC 63267-3 series
a
Add grade number to the interface reference number.
b 1
See IEC 61755-6-1 for guidance.

Figure 2 is an example of a 4,5 mm duplex plug connector interface. Table 7 gives dimensions
of the 4,5 mm duplex plug connector interface and Table 8 gives the grade of the 4,5 mm duplex
plug connector interface.
___________
Under preparation. Stage at the time of publication: IEC/CDM 61755-6-1:2021.
Figure 2 – 4,5 mm duplex plug connector interface – Push/pull
Table 7 – Dimensions of the 4,5 mm duplex plug connector interface
Dimensions
Reference Remarks
Minimum Maximum
a
A See Table 8
B 2,6 mm 2,7 mm
C 4,6 mm 4,8 mm
D
4,65 mm 4,75 mm
E 4,3 mm 4,4 mm
F 3,3 mm 3,4 mm
G
25° 35° Angle, unit in degrees
H Angle, unit in degrees
25° 35°
b
I 6,55 mm –
c
J 4,2 mm 4,5 mm
K 5,5 mm –
L 2,4 mm 2,5 mm
M 1,5 mm –
N 0,6 mm –
O
0,5 mm –
b
P 2,6 mm –
b d
Q 1,0 mm 1,1 mm
b
R
2,65 mm 2,9 mm
S 5,5 mm 5,6 mm
T 4,3 mm 4,5 mm
U – 3,7 mm
V – 2,4 mm
W 6,5 mm 6,6 mm
AB 3,7 mm 3,85 mm
AC 0,7 mm 0,9 mm
AD 0,2 mm – Radius
AE 3,0 mm –
AF
2,2 mm 2,3 mm
AJ 8,8 mm 8,9 mm
AK 8,35 mm 8,45 mm
AL
4,55 mm 4,7 mm
AM 4,45 mm 4,55 mm
AP – 3,7 mm
e
EA 32,5° 45°
Angle, unit in degrees
f
EB
5 mm 30 mm
Radius
EC 0,45 mm 0,73 mm Diameter
a
A chamfer or radius is allowed to a maximum depth of 0,5 mm from the ferrule endface.
b
The delatch housing shall be movable to the right or left. Dimensions L, M and V I, P, Q and R
are given when the delatch housing is at the furthest right.
c
Dimension J is given for the plug endface when not mated. The ferrule is movable by a certain
axial compression force with direct contacting endfaces, and therefore dimension J is variable.
Ferrule compression force shall be 5,5 N to 6,5 N when the position of the optical datum target
from the mechanical datum target is moved in the range of 3,9 mm to 4,1 mm. In addition,
dimension J shall become less than 3,25 mm with a relatively large axial compression force. The
compression force shall be measured according to IEC 61300-3-22.
d
Q is to the right of the mechanical datum target when the delatch housing is to the right
(connected state) and to the left of the mechanical datum target when the delatch housing is to
the left (disconnected state).
e
40° to 45° are desirable to minimize debris for backplane connectors.
f
Dome eccentricity of the spherically polished ferrule endface shall be less than 50 μm.

Table 8 – Grade of the 4,5 mm duplex plug connector
Dimensions
Grade A Remarks
Minimum Maximum
a
A See IEC 61755-3-1 Grade not
specified at this time
a
B See IEC 61755-3-1 Shall be as

specified in the IEC 61755 3
series
a
C See IEC 61755-3-1 Shall be as

specified in the IEC 61755 3
series
a
D See IEC 61755-3-1 Shall be as

specified in the IEC 61755 3
series
a b
A Grade not specified at this time

m
a b
B 1,246 7 1,249 5
m
Shall be as specified in the
IEC 63267-3 series
a b
C Grade not specified at this time

m
Shall be as specified in the
IEC 63267-3 series
a
Add grade number to the interface reference number.
b
See IEC 61755-6-1 for guidance.

Figure 3 is an example of a simplex adaptor connector interface. Table 9 gives dimensions of
the simplex adaptor connector interface and Table 10 gives the grade of the simplex adaptor
connector interface.
Figure 3 – Simplex adaptor connector interface – Push/pull
Table 9 – Dimensions of the simplex adaptor connector interface
Dimensions
Reference mm
Remarks
Minimum Maximum
A See Table 10 Diameter
B 2,39 2,59 Diameter
D 4,8 5
E 4,55 –
a
F 2,9 3,5
I – 6,5
J 3,9 4,1
K – 5,4
L 2,55 2,7
M – 1,4
N – 0,55
O – 0,6
P – 1,2
Q – 0,4
R – 2,55
S 5,65 5,75
U 3,8 4
V 3,3 –
W 6,7 –
AA 4,45 4,55
AB 4,01 4,11
AC 0,95 1,15
AD – 0,2 Radius
AE 2,8 2,95
AF 1,9 2,1
AG 0,3 – Radius
AH 0,4 0,55
AI 1,34 1,44 Diameter
AJ – 0,3 Radius
a
Dimension F shall become greater than 4,5 mm when a plug is coupled to or removed from the
adaptor.
Table 10 – Grade of the simplex adaptor connector
Dimensions
Grade mm Remarks
Minimum Maximum
a
– –
Resilient sleeve
a
The connector alignment feature is a resilient alignment sleeve. The feature shall accept a pin
gauge to the centre of the adaptor with a force of 1,0 N to 2,5 N under the condition that another
pin gauge is inserted into the feature from the other side. The centre of the adaptor is defined by

the right-side position of dimension J. The pin gauge is shown in Figure 4 and Table 11.

Figure 4 is an example of a pin gauge for resilient alignment sleeve. Table 11 gives pin gauge
dimensions.
Figure 4 – Pin gauge for resilient alignment sleeve
Table 11 – Pin gauge dimensions
Dimensions
mm
Reference Remarks
Minimum Maximum
LK 1,248 5 1,249 5 Surface roughness
grade N4
(0,2 μm radius)
Ra: ≤ 0,000 2
LL 2,6 2,8
LN 4,7 –
Figure 5 is an example of a 4,5 mm duplex adaptor connector interface. Table 12 gives
dimensions of the 4,5 mm duplex adaptor connector interface and Table 13 gives the grade of
the 4,5 mm duplex adaptor connector interface.
Figure 5 – 4,5 mm duplex adaptor connector interface – Push/pull
Table 12 – Dimensions of the 4,5 mm duplex adaptor connector interface
Dimensions
Reference mm
Remarks
Minimum Maximum
A See Table 13
B 2,39 2,59
D 4,8 5
E 4,55 –
a
F 2,9 3,5
I – 6,5
J 3,9 4,1
K – 5,4
L 2,55 2,7
M – 1,4
N – 0,55
O – 0,6
P – 1,2
Q – 0,4
R – 2,55
S 5,65 5,75
U 3,8 4
V 3,3 –
W 6,7 –
AA 4,45 4,55
AB 4,01 4,11
AC 0,95 1,15
AD – 0,2 Radius
AE 2,8 2,95
AF 1,9 2,1
AG 0,3 – Radius
AH 0,4 0,55
AI 1,34 1,44 Diameter
AJ – 0,3 Radius
AM 4,45 4,55
AP 3,8 4
a
Dimension F shall become greater than 4,5 mm when a plug is coupled to or removed from the
adaptor.
Table 13 – Grade of the 4,5 mm duplex adaptor connector
Dimensions
Grade mm Notes
Minimum Maximum
a
1 – –
Resilient sleeve
a
The connector alignment feature is a resilient alignment sleeve. The feature shall accept a pin
gauge to the centre of the adaptor with a force of 1,0 N to 2,5 N under the condition that another
pin gauge is inserted into the feature from the other side. The centre of the adaptor is defined by

the right-side position of dimension J. The pin gauge is shown in Figure 4 and Table 11.

Figure 6 is an example of an 8-port adaptor connector interface. Table 14 gives dimensions of
the 8-port adaptor connector interface and Table 15 gives the grade of the 8-port adaptor
connector interface.
Figure 6 – 8-port adaptor connector interface – Push/pull
Table 14 – Dimensions of the 8-port adaptor connector interface
Dimensions
Reference mm
Remarks
Minimum Maximum
A See Table 15
B 2,39 2,59
D 4,8 5
E 4,55 –
a
F 2,9 3,5
I – 6,5
J 3,9 4,1
K – 5,4
L 2,55 2,7
M – 1,4
N – 0,55
O – 0,6
P – 1,2
Q – 0,4
R – 2,55
S 5,65 5,75
U 3,8 4
V 3,3 –
W 6,7 –
AA 4,45 4,55
AB 4,01 4,11
AC 0,95 1,15
AD – 0,2 Radius
AE 2,8 2,95
AF 1,9 2,1
AG 0,3 – Radius
AH 0,4 0,55
AI 1,34 1,44 Diameter
AJ – 0,3 Radius
AM 4,45 4,55
AP 3,8 4
AQ 4,8 5,2
a
Dimension F shall become greater than 4,5 mm when a plug is coupled to or removed from the
adaptor.
Table 15 – Grade of the 8-port adaptor connector
Dimensions
Grade mm Notes
Minimum Maximum
a
1 – –
Resilient sleeve
a
The connector alignment feature is a resilient alignment sleeve. The feature shall accept a pin
gauge to the centre of the adaptor with a force of 1,0 N to 2,5 N under the condition that another
pin gauge is inserted into the feature from the other side. The centre of the adaptor is defined by
the right-side position of dimension J. The pin gauge is shown in Figure 4 and Table 11.

Figure 7 is an example of a plug connector interface. Table 16 gives dimensions of the plug
connector interface and Table 17 gives the grade of the plug connector interface.

Figure 7 – Plug connector interface – For printed board housings
Table 16 – Dimensions of the plug connector interface
Dimensions
Reference Notes
Minimum Maximum
a
A See Table 17
B 2,6 mm 2,7 mm Diameter
D 4,65 mm 4,75 mm
E 4,3 mm 4,4 mm
F 3,3 mm 3,4 mm
b
J 4,2 mm 4,5 mm
K 5,5 mm –
L 2,4 mm 2,5 mm
M 1,5 mm –
N 0,6 mm –
O 0,5 mm –
AR 3,65 mm 3,75 mm
AS 2,9 mm 3,0 mm
AT 1,7 mm 2,1 mm
AU Angle, unit in degrees
43° 47°
AV – 3,0 mm
c
EA
32,5° 45° Angle, unit in degrees
d
EB 5 mm 30 mm
Radius
EC 0,45 mm 0,73 mm
NOTE 1 A chamfer or radius is allowed to a maximum depth of 0,5 mm from the ferrule endface.
NOTE 2 40° to 45° are desirable to minimize debris for backplane connectors.
a
A chamfer or radius is allowed to a maximum depth of 0,5 mm from the ferrule endface.
b
Dimension J is given for the plug endface when not mated. The ferrule is movable by a certain
axial compression force with direct contacting endfaces, and therefore dimension J is variable.
Ferrule compression force shall be 5,5 N to 6,5 N when the position of the optical datum target
from the mechanical datum target is moved in the range of 3,9 mm to 4,1 mm. In addition,
dimension J shall become less than 3,25 mm with a relatively large axial compression force. The
compression force shall be measured according to IEC 61300-3-22.
c
40° to 45° are desirable to minimize debris for backplane connectors.
d
Dome eccentricity of the spherically polished ferrule endface shall be less than 50 μm.
...

IEC 61754-6 ®
Edition 3.0 2022-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Fibre optic interconnecting devices and passive components – Fibre optic
connector interfaces –
Part 6: Type MU connector family

Dispositifs d’interconnexion et composants passifs fibroniques – Interfaces
de connecteurs fibroniques –
Partie 6: Famille de connecteurs de type MU

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IEC 61754-6 ®
Edition 3.0 2022-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Fibre optic interconnecting devices and passive components – Fibre optic

connector interfaces –
Part 6: Type MU connector family

Dispositifs d’interconnexion et composants passifs fibroniques – Interfaces

de connecteurs fibroniques –
Partie 6: Famille de connecteurs de type MU

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.180.20 ISBN 978-2-8322-1077-9

– 2 – IEC 61754-6:2022  IEC 2022
CONTENTS
FOREWORD . 5
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 Description . 7
5 Interfaces . 8
Annex A (informative) Configuration of type MU-A connector set . 77
Annex B (informative) Configuration of type MU-B connector set . 78
Annex C (informative) Floating 2-port connector plug . 79
Annex D (informative) Panel dimensions . 80
D.1 General . 80
D.2 Simplex adaptor . 80
D.3 4,5 mm duplex adaptor . 80
D.4 6,25 mm duplex adaptor. 81
D.5 Horizontal duplex adaptor . 81
D.6 4,5 mm 8-port adaptor . 82
Bibliography . 83

Figure 1 – Simplex plug connector interface – Push/pull . 11
Figure 2 – 4,5 mm duplex plug connector interface – Push/pull . 14
Figure 3 – Simplex adaptor connector interface – Push/pull . 17
Figure 4 – Pin gauge for resilient alignment sleeve . 19
Figure 5 – 4,5 mm duplex adaptor connector interface – Push/pull . 20
Figure 6 – 8-port adaptor connector interface – Push/pull . 23
Figure 7 – Plug connector interface – For printed board housings . 25
Figure 8 – Sleeve holder interface . 27
Figure 9 – 2-port backplane housing interface . 29
Figure 10 – 2-port printed board housing interface . 33
Figure 11 – 8-port backplane housing interface . 37
Figure 12 – 8-port printed board housing interface . 41
Figure 13 – Simplex active device receptacle interface . 45
Figure 14 – Detail of the mechanical stop for rigid bore alignment feature . 47
Figure 15 – 4,5 mm duplex active device receptacle interface . 48
Figure 16 – Detail of the mechanical stop for rigid bore alignment feature . 50
Figure 17 – 6,25 mm duplex active device receptacle interface . 51
Figure 18 – Detail of the mechanical stop for rigid bore alignment feature . 53
Figure 19 – Plug connector interface – For printed board housings, APC . 54
Figure 20 – Simplex plug connector interface – Push/pull, APC . 57
Figure 21 – 4,5 mm duplex plug connector interface – Push/pull, APC . 60
Figure 22 – 6,25 mm duplex plug connector interface – Push/pull, APC . 63
Figure 23 – 6,25 mm duplex plug connector interface – Push/pull . 66
Figure 24 – 6,25 mm duplex adaptor connector interface . 69

Figure 25 – Horizontal duplex plug connector interface – Push/pull . 71
Figure 26 – Horizontal duplex adaptor connector interface . 74
Figure A.1 – Configuration of type MU-A connector set . 77
Figure B.1 – Configuration of type MU-B connector set . 78
Figure C.1 – Floating 2-port connector plug . 79
Figure D.1 – Panel cut out . 80
Figure D.2 – Panel cut out . 80
Figure D.3 – Panel cut out . 81
Figure D.4 – Panel cut out . 81
Figure D.5 – Panel cut out . 82

Table 1 – Interfaces . 8
Table 2 – Intermateability of MU-A connectors . 9
Table 3 – Intermateability of MU-B connectors . 9
Table 4 – Intermateability of MU receptacles . 10
Table 5 – Dimensions of the simplex plug connector interface . 12
Table 6 – Grade of the simplex plug connector . 13
Table 7 – Dimensions of the 4,5 mm duplex plug connector interface . 15
Table 8 – Grade of the 4,5 mm duplex plug connector . 16
Table 9 – Dimensions of the simplex adaptor connector interface . 18
Table 10 – Grade of the simplex adaptor connector . 19
Table 11 – Pin gauge dimensions . 19
Table 12 – Dimensions of the 4,5 mm duplex adaptor connector interface . 21
Table 13 – Grade of the 4,5 mm duplex adaptor connector . 22
Table 14 – Dimensions of the 8-port adaptor connector interface . 24
Table 15 – Grade of the 8-port adaptor connector . 25
Table 16 – Dimensions of the plug connector interface . 26
Table 17 – Grade of the plug connector . 27
Table 18 – Dimensions of the sleeve holder interface . 28
Table 19 – Grade of the sleeve holder . 28
Table 20 – Dimensions of the 2-port backplane housing interface . 31
Table 21 – Grade of the 2-port backplane housing . 32
Table 22 – Dimensions of the 2-port printed board housing interface . 35
Table 23 – Dimensions of the 8-port backplane housing interface . 39
Table 24 – Grade of the 8-port backplane housing . 40
Table 25 – Dimensions of the 8-port printed board housing interface . 43
Table 26 – Dimensions of the simplex active device receptacle interface . 46
Table 27 – Alignment feature grade . 47
Table 28 – Dimensions of the mechanical stop for rigid bore alignment feature . 47
Table 29 – Mechanical stop feature grade . 48
Table 30 – Dimensions of the 4,5 mm duplex active device receptacle interface . 49
Table 31 – Alignment feature grade . 50
Table 32 – Dimensions of the mechanical stop for rigid bore alignment feature . 50

– 4 – IEC 61754-6:2022  IEC 2022
Table 33 – Mechanical stop feature grade . 51
Table 34 – Dimensions of the 6,25 mm duplex active device receptacle interface . 52
Table 35 – Alignment feature grade . 53
Table 36 – Dimensions of the mechanical stop for rigid bore alignment feature . 53
Table 37 – Mechanical stop feature grade . 54
Table 38 – Dimensions of the plug connector interface – For printed board housings, APC . 55
Table 39 – Dimensions of the simplex plug connector interfaces, APC . 58
Table 40 – Dimensions of the 4,5 mm duplex plug connector interfaces, APC . 61
Table 41 – Dimensions of the 6,25 mm duplex plug connector interface, APC . 64
Table 42 – Dimensions of the 6,25 mm duplex plug connector interface . 66
Table 43 – Grade of the 6,25 mm duplex plug connector . 68
Table 44 – Dimensions of the 6,25 mm duplex adaptor connector interface . 69
Table 45 – Grade of the 6,25 mm duplex adaptor connector . 70
Table 46 – Dimensions of the horizontal duplex plug connector interface . 72
Table 47 – Grade of the horizontal duplex plug connector . 73
Table 48 – Dimensions of the horizontal duplex adaptor connector interface . 75
Table 49 – Grade of the horizontal duplex adaptor connector . 76
Table C.1 – Dimensions table for 2-port connector plug . 79
Table D.1 – Dimensions for simplex adaptor . 80
Table D.2 – Dimensions for 4,5 mm duplex adaptor . 81
Table D.3 – Dimensions for 6,25 mm duplex adaptor . 81
Table D.4 – Dimensions for horizontal duplex adaptor . 82
Table D.5 – Dimensions for 4,5 mm 8-port adaptor . 82

INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
FIBRE OPTIC INTERCONNECTING
DEVICES AND PASSIVE COMPONENTS –
FIBRE OPTIC CONNECTOR INTERFACES –

Part 6: Type MU connector family

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,
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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
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any IEC Publication and the corresponding national or regional publication shall be clearly indicated in the latter.
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6) All users should ensure that they have the latest edition of this publication.
7) No liability shall attach to IEC or its directors, employees, servants or agents including individual experts and
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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.
IEC 61754-6 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 2013 and constitutes a
technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) the test method IEC 61300-3-22 for the compression force of the ferrule was added;
b) Annex D (informative) with cut out dimension requirements for testing the strength of
mounted adaptors was added.
– 6 – IEC 61754-6:2022  IEC 2022
The text of this International Standard is based on the following documents:
Draft Report on voting
86B/4562/FDIS 86B/4585/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 of the IEC 61754 series, under the general title Fibre optic interconnecting
devices 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 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 –
FIBRE OPTIC CONNECTOR INTERFACES –

Part 6: Type MU connector family

1 Scope
This part of IEC 61754 specifies the standard interface dimensions for type MU family of
connectors.
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 61300-3-22, Fibre optic interconnecting devices and passive components – Basic test and
measurement procedures – Part 3-22: Examinations and measurements – Ferrule compression
force
IEC 61754-1, Fibre optic interconnecting devices and passive components – Fibre optic
connector interfaces – Part 1: General and guidance
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 61754-1 apply.
ISO and IEC maintain terminological databases for use in standardization at the following
addresses:
• IEC Electropedia: available at http://www.electropedia.org/
• ISO Online browsing platform: available at http://www.iso.org/obp
4 Description
The parent connector for type MU connector family is a miniature single-position plug which is
characterized by a cylindrical, spring-loaded butting ferrule(s) of a 1,25 mm typical diameter,
and a push-pull coupling mechanism. The optical alignment mechanism of the connectors is of
a rigid hole or a resilient sleeve style.
This document type MU connector family defines the standard interface dimensions of active
device receptacles for the type MU connectors. The receptacles are used to retain the connector
plugs and mechanically maintain the optical datum target of the plugs at a defined position
within the receptacle housings.

– 8 – IEC 61754-6:2022  IEC 2022
5 Interfaces
This document contains the standard interfaces showed in Table 1.
Table 1 – Interfaces
Interface IEC 61754-6-1 Simplex plug connector interface – Push/pull (see Figure 1)
Interface IEC 61754-6-2 4,5 mm duplex plug connector interface – Push/pull (see Figure 2)
Interface IEC 61754-6-3 Simplex adaptor connector interface – Push/pull (see Figure 3)
Interface IEC 61754-6-4 4,5 mm duplex adaptor connector interface – Push/pull (see Figure 5)
Interface IEC 61754-6-5 8-port adaptor connector interface – Push/pull (see Figure 6)
Interface IEC 61754-6-6 Plug connector interface – for printed board housings (see Figure 7)
Interface IEC 61754-6-7 Sleeve holder interface – for printed board housings (see Figure 8)
Interface IEC 61754-6-8 2-port backplane housing interface – Self-retentive (see Figure 9)
Interface IEC 61754-6-9 2-port printed board housing interface – Self-retentive (see Figure 10)
Interface IEC 61754-6-10 8-port backplane housing interface – Self-retentive (see Figure 11)
Interface IEC 61754-6-1 8-port printed board housing interface – Self-retentive (see Figure 12)
Interface IEC 61754-6-12 Simplex active device receptacle interface – for physical contact (PC) connector
plug (see Figure 13)
Interface IEC 61754-6-13 4,5 mm duplex active device receptacle interface – for PC connector plug
(see Figure 15)
Interface IEC 61754-6-14 6,25 mm duplex active device receptacle interface – for PC connector plug
(see Figure 17)
Interface IEC 61754-6-15 Plug connector interface – for printed board housings, angled PC (APC) 8
degrees (see Figure 19)
Interface IEC 61754-6-16 Simplex plug connector interface – Push/pull, APC 8 degrees (see Figure 20)
Interface IEC 61754-6-17 4,5 mm duplex plug connector interface – Push/pull, APC 8 degrees
(see Figure 21)
Interface IEC 61754-6-18 6,25 mm duplex plug connector interface – Push/pull, APC 8 degrees
(see Figure 22)
Interface IEC 61754-6-19 6,25 mm duplex plug connector interface – Push/pull (see Figure 23)
Interface IEC 61754-6-20 6,25 mm duplex adaptor connector interface – Push/pull (see Figure 24)
Interface IEC 61754-6-21 Horizontal duplex plug connector interface – Push/pull (see Figure 25)
Interface IEC 61754-6-22 Horizontal duplex adaptor connector interface – Push/pull (see Figure 26)

The plugs of interfaces IEC 61754-6-1, IEC 61754-6-2, IEC 61754-6-6, IEC 61754-6-19 and
IEC 61754-6-21 have a ferrule(s) with a spherically polished endface, and realize physical
contact (PC). The plugs of interfaces IEC 61754-6-15, IEC 61754-6-16, IEC 61754-6-17 and
IEC 61754-6-18 have a ferrule(s) with a spherically polished angled endface and realize angled
PC (APC).
The type MU connector family comprises two types of connector set: MU-A connector set
(see Annex A) and MU-B connector set (see Annex B). The MU-A connector set is a
plug/adaptor configuration with a push-pull coupling mechanism. The MU-B connector set is a
plug-in type back-plane connector configuration which is plug/backplane and printed board
housings/plug for printed board housing/sleeve holder configuration and is equipped with a self-
retentive mechanism.
The type MU-A connector set consists of simplex and duplex plugs, and simplex, duplex and
8-port adaptors. The plugs are common to the backplane connector housings of the type MU-B
connector set.
The type MU-B connector set consists of 2-port and 8-port backplane and printed board
connector housings, simplex and duplex plugs, plug for printed board connector housings, and
sleeve holder. The plug for printed board connector housing is used as a jack together with the
sleeve holder. The jack is attached into the printed board connector housing.
Table 2, Table 3 and Table 4 show the intermateablitiy of the standard interfaces. It shall be
noted however that in order to obtain the designated optical performance, any plug shall be
connected to a counterpart plug whose ferrule end is polished to the same condition.
Table 2 – Intermateability of MU-A connectors
Adaptors
Plugs
61754-6-3 61754-6-4 61754-6-5 61754-6-20 61754- 6-22
61754-6-1 Mate Mate Mate Mate Mate
61754-6-2 Not mate Mate Mate Not mate Not mate
61754-6-16 Mate Mate Mate Mate Mate
61754- 6-17 Not mate Mate Mate Not mate Not mate
61754-6-18 Not mate Not mate Not mate Mate Not mate
61754-6-19 Not mate Not mate Not mate Mate Not mate
61754-6-21 Not mate Not mate Not mate Not mate Mate

Table 3 – Intermateability of MU-B connectors
Connector housings
Backplane connector Printed board connector
Plugs
housing housing
61754-6-8 61754-6-10 61754-6-9 61754-6-11
61754-6-1 Mate Mate Not mate Not mate
61754-6-2 Mate Mate Not mate Not mate
61754-6-6 with 61754-6-7 Not mate Not mate Mate Mate
61754-6-15 with 61754- 6-7
Not mate Not mate Mate Mate
61754-6-16 Mate Mate Not mate Not mate
61754-6-17 Mate Mate Not mate Not mate
61754-6-18 Not mate Not mate Not mate Not mate
61754-6-19 Not mate Not mate Not mate Not mate
61754-6-21 Not mate Not mate Not mate Not mate

– 10 – IEC 61754-6:2022  IEC 2022
Table 4 – Intermateability of MU receptacles
Receptacles
Plugs
61754-6-12 61754-6-13 61754-6-14
61754-6-1 Mate Mate Mate
61754-6-2 Not mate Mate Not mate
61754-6-16 Not mate Not mate Not mate
61754-6-17 Not mate Not mate Not mate
61754-6-18 Not mate Not mate Not mate
61754-6-19 Not mate Not mate Mate
61754-6-21 Not mate Not mate Not mate

Figure 1 is an example of a simplex plug connector interface. Table 5 gives dimensions of the
simplex plug connector interface and Table 6 gives the grade of the simplex plug connector
interface.
Figure 1 – Simplex plug connector interface – Push/pull

– 12 – IEC 61754-6:2022  IEC 2022
Table 5 – Dimensions of the simplex plug connector interface
Dimensions
Reference Remarks
Minimum Maximum
a
A See Table 6
B 2,6 mm 2,7 mm
C
4,6 mm 4,8 mm
D 4,65 mm 4,75 mm
E 4,3 mm 4,4 mm
F
3,3 mm 3,4 mm
G Angle, unit in degrees
25° 35°
H 25° 35° Angle, unit in degrees
b
I 6,55 mm –
c
J
4,2 mm 4,5 mm
K 5,5 mm –
L 2,4 mm 2,5 mm
M 1,5 mm –
N 0,6 mm –
O 0,5 mm –
b
P 2,6 mm –
b d
Q
1 mm 1,1 mm
b
R 2,65 mm 2,9 mm
S 5,5 mm 5,6 mm
T 4,3 mm 4,5 mm
U – 3,7 mm
V – 2,4 mm
W 6,5 mm 6,6 mm
AA 4,3 mm 4,4 mm
AB 3,85 mm 3,95 mm
AC 0,7 mm 0,9 mm
AD
0,2 mm – Radius
AE 3 mm –
AF 2,2 mm 2,3 mm
e
EA
32,5° 45°
Angle, unit in degrees
f
EB 5 mm 30 mm
Radius
EC 0,45 mm 0,73 mm Diameter
a
A chamfer or radius is allowed to a maximum depth of 0,5 mm from the ferrule endface.
b
The delatch housing shall be movable to the right or left. Dimensions L, M and V are given when
the delatch housing is at the furthest right.
c
Dimension J is given for the plug endface when not mated. The ferrule is movable by a certain
axial compression force with direct contacting endfaces, and therefore dimension J is variable.
Ferrule compression force shall be 5,5 N to 6,5 N when the position of the optical datum target
from the mechanical datum target is moved in the range of 3,9 mm to 4,1 mm. In addition,
dimension J shall become less than 3,25 mm with a relatively large axial compression force. The
compression force shall be measured according to IEC 61300-3-22.
d
Q is to the right of the mechanical datum target when the delatch housing is to the right
(connected state) and to the left of the mechanical datum target when the delatch housing is to
the left (disconnected state).
e
40° to 45° are desirable to minimize debris for backplane connectors.
f
Dome eccentricity of the spherically polished ferrule endface shall be less than 50 µm.

Table 6 – Grade of the simplex plug connector
Dimensions
mm
Grade Remarks
A
Minimum Maximum
a
A See IEC 61755-3-1
a
B See IEC 61755-3-1
a
C See IEC 61755-3-1
a
D See IEC 61755-3-1
a b
A Grade not specified at this time

m
a b
B 1,246 7 1,249 5
m
a b
C Grade not specified at this time

m
a
Add grade number to the interface reference number.
b 1
See IEC 61755-6-1 for guidance.

Figure 2 is an example of a 4,5 mm duplex plug connector interface. Table 7 gives dimensions
of the 4,5 mm duplex plug connector interface and Table 8 gives the grade of the 4,5 mm duplex
plug connector interface.
___________
Under preparation. Stage at the time of publication: IEC/CDM 61755-6-1:2021.

– 14 – IEC 61754-6:2022  IEC 2022

Figure 2 – 4,5 mm duplex plug connector interface – Push/pull

Table 7 – Dimensions of the 4,5 mm duplex plug connector interface
Dimensions
Reference Remarks
Minimum Maximum
a
A
See Table 8
B 2,6 mm 2,7 mm
C 4,6 mm 4,8 mm
D 4,65 mm 4,75 mm
E 4,3 mm 4,4 mm
F 3,3 mm 3,4 mm
G 25° 35° Angle, unit in degrees
H Angle, unit in degrees
25° 35°
b
I 6,55 mm –
c
J 4,2 mm 4,5 mm
K 5,5 mm –
L
2,4 mm 2,5 mm
M 1,5 mm –
N 0,6 mm –
O 0,5 mm –
b
P 2,6 mm –
b d
Q 1,0 mm 1,1 mm
b
R 2,65 mm 2,9 mm
S 5,5 mm 5,6 mm
T 4,3 mm 4,5 mm
U – 3,7 mm
V
– 2,4 mm
W 6,5 mm 6,6 mm
AB 3,7 mm 3,85 mm
AC
0,7 mm 0,9 mm
AD 0,2 mm – Radius
AE 3,0 mm –
AF 2,2 mm 2,3 mm
AJ 8,8 mm 8,9 mm
AK 8,35 mm 8,45 mm
AL 4,55 mm 4,7 mm
AM 4,45 mm 4,55 mm
AP – 3,7 mm
e
EA 32,5° 45°
Angle, unit in degrees
f
EB 5 mm 30 mm
Radius
EC
0,45 mm 0,73 mm Diameter
a
A chamfer or radius is allowed to a maximum depth of 0,5 mm from the ferrule endface.
b
The delatch housing shall be movable to the right or left. Dimensions L, M and V are given when
the delatch housing is at the furthest right.
c
Dimension J is given for the plug endface when not mated. The ferrule is movable by a certain
axial compression force with direct contacting endfaces, and therefore dimension J is variable.
Ferrule compression force shall be 5,5 N to 6,5 N when the position of the optical datum target
from the mechanical datum target is moved in the range of 3,9 mm to 4,1 mm. In addition,
dimension J shall become less than 3,25 mm with a relatively large axial compression force. The
compression force shall be measured according to IEC 61300-3-22.
d
Q is to the right of the mechanical datum target when the delatch housing is to the right
(connected state) and to the left of the mechanical datum target when the delatch housing is to
the left (disconnected state).
e
40° to 45° are desirable to minimize debris for backplane connectors.
f
Dome eccentricity of the spherically polished ferrule endface shall be less than 50 μm.

– 16 – IEC 61754-6:2022  IEC 2022
Table 8 – Grade of the 4,5 mm duplex plug connector
Dimensions
Grade A Remarks
Minimum Maximum
a
A See IEC 61755-3-1
a
B See IEC 61755-3-1
a
C See IEC 61755-3-1
a
D See IEC 61755-3-1
a b
A Grade not specified at this time

m
a b
B 1,246 7 1,249 5
m
a b
C Grade not specified at this time

m
a
Add grade number to the interface reference number.
b
See IEC 61755-6-1 for guidance.

Figure 3 is an example of a simplex adaptor connector interface. Table 9 gives dimensions of
the simplex adaptor connector interface and Table 10 gives the grade of the simplex adaptor
connector interface.
Figure 3 – Simplex adaptor connector interface – Push/pull

– 18 – IEC 61754-6:2022  IEC 2022
Table 9 – Dimensions of the simplex adaptor connector interface
Dimensions
mm
Reference Remarks
Minimum Maximum
A See Table 10 Diameter
B 2,39 2,59 Diameter
D 4,8 5
E 4,55 –
a
F 2,9 3,5
I – 6,5
J 3,9 4,1
K – 5,4
L 2,55 2,7
M – 1,4
N – 0,55
O – 0,6
P – 1,2
Q – 0,4
R – 2,55
S 5,65 5,75
U 3,8 4
V 3,3 –
W 6,7 –
AA 4,45 4,55
AB 4,01 4,11
AC 0,95 1,15
AD – 0,2 Radius
AE 2,8 2,95
AF 1,9 2,1
AG 0,3 – Radius
AH 0,4 0,55
AI 1,34 1,44 Diameter
AJ – 0,3 Radius
a
Dimension F shall become greater than 4,5 mm when a plug is coupled to or removed from the
adaptor.
Table 10 – Grade of the simplex adaptor connector
Dimensions
Grade mm Remarks
Minimum Maximum
a
1 – –
Resilient sleeve
a
The connector alignment feature is a resilient alignment sleeve. The feature shall accept a pin
gauge to the centre of the adaptor with a force of 1,0 N to 2,5 N under the condition that another
pin gauge is inserted into the feature from the other side. The centre of the adaptor is defined by

the right-side position of dimension J. The pin gauge is shown in Figure 4 and Table 11.

Figure 4 is an example of a pin gauge for resilient alignment sleeve. Table 11 gives pin gauge
dimensions.
Figure 4 – Pin gauge for resilient alignment sleeve
Table 11 – Pin gauge dimensions
Dimensions
Reference mm Remarks
Minimum Maximum
LK 1,248 5 1,249 5 Surface roughness
grade N4
(0,2 μm radius)
LL 2,6 2,8
LN 4,7 –
Figure 5 is an example of a 4,5 mm duplex adaptor connector interface. Table 12 gives
dimensions of the 4,5 mm duplex adaptor connector interface and Table 13 gives the grade of
the 4,5 mm duplex adaptor connector interface.

– 20 – IEC 61754-6:2022  IEC 2022

Figure 5 – 4,5 mm duplex adaptor connector interface – Push/pull

Table 12 – Dimensions of the 4,5 mm duplex adaptor connector interface
Dimensions
mm
Reference Remarks
Minimum Maximum
A See Table 13
B 2,39 2,59
D 4,8 5
E 4,55 –
a
F 2,9 3,5
I – 6,5
J 3,9 4,1
K – 5,4
L 2,55 2,7
M – 1,4
N – 0,55
O – 0,6
P – 1,2
Q – 0,4
R – 2,55
S 5,65 5,75
U 3,8 4
V 3,3 –
W 6,7 –
AA 4,45 4,55
AB 4,01 4,11
AC 0,95 1,15
AD – 0,2 Radius
AE 2,8 2,95
AF 1,9 2,1
AG 0,3 – Radius
AH 0,4 0,55
AI 1,34 1,44 Diameter
AJ – 0,3 Radius
AM 4,45 4,55
AP 3,8 4
a
Dimension F shall become greater than 4,5 mm when a plug is coupled to or removed from the
adaptor.
– 22 – IEC 61754-6:2022  IEC 2022
Table 13 – Grade of the 4,5 mm duplex adaptor connector
Dimensions
Grade mm Notes
Minimum Maximum
a
1 – –
Resilient sleeve
a
The connector alignment feature is a resilient alignment sleeve. The feature shall accept a pin
gauge to the centre of the adaptor with a force of 1,0 N to 2,5 N under the condition that another
pin gauge is inserted into the feature from the other side. The centre of the adaptor is defined by

the right-side position of dimension J. The pin gauge is shown in Figure 4 and Table 11.

Figure 6 is an example of an 8-port adaptor connector interface. Table 14 gives dimensions of
the 8-port adaptor connector interface and Table 15 gives the grade of the 8-port adaptor
connector interface.
Figure 6 – 8-port adaptor connector interface – Push/pull

– 24 – IEC 61754-6:2022  IEC 2022
Table 14 – Dimensions of the 8-port adaptor connector interface
Dimensions
mm
Reference Remarks
Minimum Maximum
A See Table 15
B 2,39 2,59
D 4,8 5
E 4,55 –
a
F 2,9 3,5
I – 6,5
J 3,9 4,1
K – 5,4
L 2,55 2,7
M – 1,4
N – 0,55
O – 0,6
P – 1,2
Q – 0,4
R – 2,55
S 5,65 5,75
U 3,8 4
V 3,3 –
W 6,7 –
AA 4,45 4,55
AB 4,01 4,11
AC 0,95 1,15
AD – 0,2 Radius
AE 2,8 2,95
AF 1,9 2,1
AG 0,3 – Radius
AH 0,4 0,55
AI 1,34 1,44 Diameter
AJ – 0,3 Radius
AM 4,45 4,55
AP 3,8 4
AQ 4,8 5,2
a
Dimension F shall become greater than 4,5 mm when a plug is coupled to or removed from the
adaptor.
Table 15 – Grade of the 8-port adaptor connector
Dimensions
Grade mm Notes
Minimum Maximum
a
1 – –
Resilient sleeve
a
The connector alignment feature is a resilient alignment sleeve. The feature shall accept a pin
gauge to the centre of the adaptor with a force of 1,0 N to 2,5 N under the condition that another
pin gauge is inserted into the feature from the other side. The centre of the adaptor is defined by
the right-side position of dimension J. The pin gauge is shown in Figure 4 and Table 11.

Figure 7 is an example of a plug connector interface. Table 16 gives dimensions of the plug
connector interface and Table 17 gives the grade of the plug connector interface.

Figure 7 – Plug connector interface – For printed board housings

– 26 – IEC 61754-6:2022  IEC 2022
Table 16 – Dimensions of the plug connector interface
Dimensions
Reference Notes
Minimum Maximum
a
A See Table 17
B 2,6 mm 2,7 mm Diameter
D 4,65 mm 4,75 mm
E 4,3 mm 4,4 mm
F 3,3 mm 3,4 mm
b
J 4,2 mm 4,5 mm
K 5,5 mm –
L 2,4 mm 2,5 mm
M 1,5 mm –
N 0,6 mm –
O 0,5 mm –
AR 3,65 mm 3,75 mm
AS 2,9 mm 3,0 mm
AT 1,7 mm 2,1 mm
AU Angle, unit in degrees
43° 47°
AV – 3,0 mm
c
EA
32,5° 45°
Angle, unit in degrees
d
EB 5 mm 30 mm
Radius
EC 0,45 mm 0,73 mm
NOTE 1 A chamfer or radius is allowed to a maximum depth of 0,5 mm from the ferrule endface.
NOTE 2 40° to 45° are desirable to minimize debris for backplane connectors.
a
A chamfer or radius is allowed to a maximum depth of 0,5 mm from the ferrule endface.
b
Dimension J is given for the plug endface when not mated. The ferrule is movable by a certain
axial compression force with direct contacting endfaces, and therefore dimension J is variable.
Ferrule compression force shall be 5,5 N to 6,5 N when the position of the optical datum target
from the mechanical datum target is moved
...