IEC 61754-35:2020

IEC 61754-35 ®
Edition 1.0 2020-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Fibre optic interconnecting devices and passive components – Fibre optic
connector interfaces –
Part 35: Type LSHE connector family for harsh environments

Dispositifs d’interconnexion et composants passifs fibroniques – Interfaces
de connecteurs fibroniques –
Partie 35: Famille de connecteurs de type LSHE pour environnements hostiles

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IEC 61754-35 ®
Edition 1.0 2020-04
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Fibre optic interconnecting devices and passive components – Fibre optic

connector interfaces –
Part 35: Type LSHE connector family for harsh environments

Dispositifs d’interconnexion et composants passifs fibroniques – Interfaces

de connecteurs fibroniques –
Partie 35: Famille de connecteurs de type LSHE pour environnements hostiles

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 33.180.20 ISBN 978-2-8322-8109-3

– 2 – IEC 61754-35:2020  IEC 2020
CONTENTS
FOREWORD . 3
INTRODUCTION . 5
1 Scope . 6
2 Normative references . 6
3 Terms and definitions . 6
4 Description . 6
5 Connector Interfaces . 6
5.1 General . 6
5.2 Plug connector interface . 7
5.3 Plug connector interface . 9
6 Interfaces . 11
7 Ferrule grades . 12
8 Ferrule position . 12
9 Pin gauge for adaptor . 13
Annex A (informative)  Panel cutout dimensions . 15
Bibliography . 16

Figure 1 – Plug connector interface (isometric view) . 7
Figure 2 – Plug connector mating dimensions . 8
Figure 3 – Expanded view from direction A (APC type) . 8
Figure 4 – Socket connector interface (isometric view) . 10
Figure 5 – Socket connector mating dimensions . 10
Figure 6 – Expanded view from direction A (APC type) . 10
Figure 7 – Insert’s front view (top left) and side view without (top right) and with
(bottom) adaptor . 12
Figure 8 – Pin gauge for adaptor . 14
Figure A.1 – Panel cutout for socket . 15

Table 1 – Intermateability between plugs and sockets within the IEC 61754-35 family . 7
Table 2 – Plug connector dimensions . 9
Table 3 – Socket connector dimensions . 11
Table 4 – Ferrule grades . 12
Table 5 – Ferrule position . 13
Table 6 – Insert dimensions . 13
Table 7 – Pin gauge dimensions . 14
Table A.1 – Dimensions of the panel cutout . 15

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

Part 35: Type LSHE connector family for harsh environments

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
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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.
International Standard IEC 61754-35 has been prepared by subcommittee 86B: Fibre optic
interconnecting devices and passive components, of IEC technical committee 86: Fibre optics.
The text of this International Standard is based on the following documents:
FDIS Report on voting
86B/4271/FDIS 86B/4285/RVD
Full information on the voting for the approval of this International Standard can be found in the
report on voting indicated in the above table.
This document has been drafted in accordance with the ISO/IEC Directives, Part 2.
A list of all parts in the IEC 61754 series, published under the general title Fibre optic
interconnecting devices and passive components – Fibre optic connector interfaces, can be
found on the IEC website.
– 4 – IEC 61754-35:2020  IEC 2020
The committee has decided that the contents of this document will remain unchanged until the
stability date indicated on the IEC website under "http://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.
INTRODUCTION
The International Electrotechnical Commission (IEC) draws attention to the fact that it is claimed
that compliance with this document may involve the use of a patent concerning connector
structure given in clause 5.
IEC takes no position concerning the evidence, validity and scope of this patent right.
The holder of this patent right has assured the IEC that he/she is willing to negotiate licences
under reasonable and non-discriminatory terms and conditions with applicants throughout the
world. In this respect, the statement of the holder of this patent right is registered with IEC.
Information may be obtained from:
DIAMOND SA
Via dei Patrizi 5
6616 Losone
Switzerland
Attention is drawn to the possibility that some of the elements of this document may be the
subject of patent rights other than those identified above. IEC shall not be held responsible for
identifying any or all such patent rights.
ISO (www.iso.org/patents) and IEC (http://patents.iec.ch) maintain on-line data bases of
patents relevant to their standards. Users are encouraged to consult the data bases for the
most up to date information concerning patents.

– 6 – IEC 61754-35:2020  IEC 2020
FIBRE OPTIC INTERCONNECTING DEVICES AND PASSIVE
COMPONENTS – FIBRE OPTIC CONNECTOR INTERFACES –

Part 35: Type LSHE connector family for harsh environments

1 Scope
This part of IEC 61754 defines the standard connector interface dimensions for LSHE family of
connectors with up to four termini. This connector family is targeting deployment under harsh
environmental conditions.
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 61753-1, Fibre optic interconnecting devices and passive components – Performance
standard – Part 1: General and guidance
IEC 61754-1, Fibre optic interconnecting devices and passive components – Fibre optic
connector interfaces – Part 1: General and guidance
IEC 61755 (all parts), Fibre optic interconnecting devices and passive components – Connector
optical interfaces
3 Terms and definitions
No terms and definitions are listed in this document.
4 Description
The LSHE connector family is intended to be used outdoor, in industrial and, more generally, in
harsh environments. It is therefore designed to survive under harsh conditions, according to
IEC 61753-1. A connection comprises a plug connector and a socket, each one containing an
insert with up to four termini. Each terminus hosts a 2,5 mm (nominal) ferrule, which may be
physical contact (PC) or angled PC (APC) polished. Within a connection, the ferrules are aligned
through resilient sleeves housed in an adaptor that may be fixed either on the plug side or on
the socket side (hermaphrodite connection system). Each terminus may support any type of
fibre (SM, MM or other) provided the termini facing each other in the connection contain
compatible fibres. The same applies to the polishing type (PC or APC) of the mating termini.
Within one connector, different types of fibre and termini may be used. The mechanical
connection between the plug connector and the socket is ensured by a push-pull mechanism.
5 Connector Interfaces
5.1 General
General requirements defined in IEC 61754-1 shall be applied for this document.

This document contains the following standard interfaces:
• interface IEC 61754-35-1: four-way plug connector interface;
• interface IEC 61754-35-2: four-way socket connector interface.
The plugs and sockets shown in Table 1 are intermateable.
Table 1 – Intermateability between plugs and sockets within
the IEC 61754-35 family
Plugs Socket
- 61754-35-2
61754-35-1 mate
5.2 Plug connector interface
The isometric view of the plug connector interface with the protection cap open is shown in
Figure 1. In this example, two of the four termini are equipped with adaptors.

NOTE Two adaptors are displayed, and the protection cap is open.
Figure 1 – Plug connector interface (isometric view)
The side and front views of the plug connector are illustrated in Figure 2 while the orientation
of the APC ferrule with respect to the connector is shown in Figure 3, where the optical
reference plane is defined as the plane passing through the nominal fibre centre and parallel to
the mechanical reference plane. The relevant dimensions are listed in Table 2.

– 8 – IEC 61754-35:2020  IEC 2020

Figure 2 – Plug connector mating dimensions

Figure 3 – Expanded view from direction A (APC type)

Table 2 – Plug connector dimensions
Reference Dimensions Notes
Minimum Basic Maximum
A 13,28 mm 13,35 mm Diameter
B 14,20 mm 14,50 mm Diameter
C 21,20 mm 21,60 mm
a
34,45 mm 34,55 mm
D
E 9,95 mm 10,15 mm
F 10,95 mm 11,15 mm
G 12,90 mm 13,40 mm
H 9,80 mm 10,20 mm
a
12,40 mm 12,50 mm
J
K 7,45 mm 7,55 mm
L 36,40 mm 36,70 mm
M 50,00 mm 50,25 mm
b
50,5 mm 50,9 mm
N
P 12,75 mm 13,00 mm
R 17,70 mm 17,80 mm
S 19,9 mm 20,0 mm
a
20,5 mm 20,8 mm
T
U 10,8 mm 11,0 mm
V 19,20 mm 19,50 mm
W 6 mm -
a
3 mm 3,1 mm
Y
Z 24,1 mm -
AA 29,8 mm 30,05 mm
AB 2,82 mm 2,95 mm
AC 7,9 mm 8,7 mm
AD 2,9 mm 3,0 mm
AE 21,5 mm 21,8 mm
AF 0,1 mm 0,6 mm
AG 10,4 mm 10,6 mm
c
8° Angle in degrees
AH
a
Material and dimensions compatible with application environment.
b
Dimension N is given when plug connector is not mated and may change under axial compression forces onto
the spring-loaded insert in a mating configuration.
c
For APC ferrules only.
5.3 Plug connector interface
A cross section of the socket connector interface is shown in Figure 4 with an example of a
possible configuration of the adaptors mounted on two of the four possible termini. The relevant
dimensions and the relative orientation of the APC ferrules with respect to the socket are shown
in Figure 5 and Figure 6, respectively. The socket’s dimensions are listed in Table 3. For
information about panel cutout dimensions, please see Annex A.

– 10 – IEC 61754-35:2020  IEC 2020

Figure 4 – Socket connector interface (isometric view)

Figure 5 – Socket connector mating dimensions

Figure 6 – Expanded view from direction A (APC type)

Table 3 – Socket connector dimensions
Reference Dimensions Notes
Minimum Basic Maximum
A 13,40 mm 13,45 mm Diameter
B 13,95 mm 14,05 mm Diameter
a
34,65 mm 34,80 mm
D
E 10,20 mm 10,25 mm
F 11,20 mm 11,25 mm
G 13,6 mm 14,3 mm
H 6,5 mm 7,5 mm
a
J 12,65 mm 12,75 mm
K 7,8 mm 8,2 mm
L 35,8 mm 36,2 mm
M 50,35 mm 50,60 mm
N 49,1 mm 49,5 mm
P 13,15 mm 13,30 mm
R 17,85 mm 17,95 mm
S 20,05 mm 20,25 mm
a
20,90 mm 21,15 mm
T
U 11,05 mm 11,20 mm
V 20,90 mm 21,15 mm
W 2,6 mm 3,2 mm
a
2,7 mm 2,9 mm
Y
Z 21,0 mm 21,5 mm
AA 30,1 mm 30,3 mm
AB 3,15 mm 3,25 mm
AD 2,8 mm 2,9 mm
AE 22,0 mm 22,5 mm
AF 0,65 mm 0,90 mm
AG 10,8 mm 11,2 mm
b
8° Angle in degrees
AH
AJ 29,9 mm 30,1 mm
a
Socket without sealing.
b
For APC ferrules only.
6 Interfaces
The plugs and sockets of the IEC 61754-35 family shall have ferrules with a spherically polished
end-face to provide an appropriate physical contact (PC) or angled physical contact (APC)
according to IEC 61755 (all parts).

– 12 – IEC 61754-35:2020  IEC 2020
7 Ferrule grades
The individual optical interfaces inside both connector plug and socket can accommodate
ferrules of different grades according to Table 4.
Table 4 – Ferrule grades
A
Grade Minimum Maximum
mm mm
0 2,499 0 2,499 5
1 2,498 5 2,499 5
2 2,498 3 2,499 5
8 Ferrule position
The geometrical positioning of the ferrules inside the inserts mounted in both the connector
plug and the socket interface is shown in Figure 7, while the relevant dimensions are listed in
Table 5 and Table 6, respectively.

Figure 7 – Insert’s front view (top left) and side view
without (top right) and with (bottom) adaptor

Table 5 – Ferrule position
X Y
Contact
mm mm
A –2,70 2,70
B 2,70 2,70
C 2,70 –2,70
D –2,70 –2,70
The ferrule positions reported in Table 5 comply with tolerances given in Figure 7 by the true
position, where reference A and reference B are defined in Figure 2 and Figure 5.
Table 6 – Insert dimensions
Reference Dimensions Notes
Minimum Basic Maximum
BA 6,73 mm 6,77 mm
a
0,2 mm 0,6 mm
...