IEC 60917-2-3:2006

Modular order for the development of mechanical structures for electronic equipment practices - Part 2-3: Sectional specification - Interface co-ordination dimensions for the 25 mm equipment practice - Extended detail specification - Dimensions for subracks, chassis, backplanes, front panels and plug-in units

IEC 60917-2-3:2006 Provides additional dimensions for a modular range of subracks and associated plug-in units based on IEC 60917-2-2. A typical subrack consists of a frame design with mounting dimensions for installation into racks or cabinets in accordance with IEC 60917-2-1. The aperture dimensions of a subrack are specified in order to meet the mounting dimensions of front plug-in units. This part of IEC 60917 comprises additional dimensions for subracks and subrack associated plug-in units with injector/extractor handle, dimensions for basic electromagnetic shielding provisions, dimensions of the key/coding system for subrack and plug-in units, dimensions of the alignment pin for front panel and plug-in unit, dimensions of electrostatic discharge provisions and dimensions of rear-mounted plug-in units. This bilingual version (2013-06) corresponds to the monolingual English version, published in 2006-05. Key words: subrack, plug in units, chassis

Ordre modulaire pour le développement des structures mécaniques pour les infrastructures électroniques - Partie 2-3: Spécification intermédiaire - Dimensions de coordination pour les interfaces des infrastructures au pas de 25 mm - Spécification particulière étendue - Dimensions pour bacs, châssis, fonds de paniers, faces avant et unités enfichables

La CEI 60917-2-3:2006 Fournit d'autres dimensions pour une gamme modulaire de bacs et d'unités enfichables associées basées sur la CEI 60917-2-2. Un bac typique est constitué d'un cadre avec des dimensions de montage pour l'installation dans des bâtis ou des baies selon la CEI 60917-2-1. Les dimensions des ouvertures d'un bac sont spécifiées pour satisfaire aux dimensions de montage des unités enfichables avant. La présente partie de la CEI 60917 comprend d'autres dimensions pour des bacs et des unités enfichables associées aux bacs avec une poignée d'introduction/extraction, des dimensions de dispositifs de blindage électromagnétiques de base, des dimensions de système de codage/verrouillage pour les bacs et les unités enfichables, des dimensions de tige d'alignement pour les panneaux avant et les unités enfichables, des dimensions de dispositifs de décharge électrostatique et des dimensions d'unités enfichables montées sur l'arrière. La présente version bilingue (2013-06) correspond à la version anglaise monolingue publiée en 2006-05. Mots-clés : bac, unités enfichables, châssis

General Information

• Status: Published
• Publication Date: 08-May-2006
• ICS: 31.240 - Mechanical structures for electronic equipment
• Technical Committee: SC 48D - Mechanical structures for electrical and electronic equipment
• Drafting Committee: WG 2 - TC 48/SC 48D/WG 2
• Current Stage: PPUB - Publication issued
• Start Date: 09-May-2006
• Completion Date: 15-Nov-2006

Standards Content (Sample)

INTERNATIONAL IEC
STANDARD 60917-2-3
First edition
2006-05
Modular order for the development
of mechanical structures
for electronic equipment practices –

Part 2-3:
Sectional specification –
Interface co-ordination dimensions
for the 25 mm equipment practice –
Extended detail specification –
Dimensions for subracks, chassis, backplanes,
front panels and plug-in units

Reference number
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INTERNATIONAL IEC
STANDARD 60917-2-3
First edition
2006-05
Modular order for the development
of mechanical structures
for electronic equipment practices –

Part 2-3:
Sectional specification –
Interface co-ordination dimensions
for the 25 mm equipment practice –
Extended detail specification –
Dimensions for subracks, chassis, backplanes,
front panels and plug-in units

 IEC 2006  Copyright - all rights reserved
No part of this publication may be reproduced or utilized in any form or by any means, electronic or
mechanical, including photocopying and microfilm, without permission in writing from the publisher.
International Electrotechnical Commission, 3, rue de Varembé, PO Box 131, CH-1211 Geneva 20, Switzerland
Telephone: [phone] Telefax: [phone] E-mail: [e-mail] Web: www.iec.ch
PRICE CODE
Commission Electrotechnique Internationale V
International Electrotechnical Commission
МеждународнаяЭлектротехническаяКомиссия
For price, see current catalogue

– 2 – 60917-2-3  IEC:2006(E)
CONTENTS
FOREWORD.4
INTRODUCTION.6

1 Scope and object.8
2 Normative references .8
3 Terms and definitions .9
4 Arrangement overview.9
5 Subrack dimensions for injector/extractor handle of plug-in units.10
5.1 Subrack interface dimensions.10
6 Dimensions of injector/extractor handle for plug-in units .12
6.1 Injector/extractor handle interface dimensions.12
6.2 Handle-locking function .14
7 Subrack and plug-in units with electromagnetic shielding provision .14
7.1 Subrack interface dimensions for electromagnetic shielding provision .14
7.2 Front panel/plug-in unit interface dimensions .17
8 Key/coding system for subrack and plug-in units .18
8.1 Subrack interface dimensions – Key/coding system on the plug-in unit guides .19
8.2 Key dimensions – Key/coding system on the plug-in unit guides.20
8.3 Programming of key – Key/coding system on the plug-in guides.22
8.4 Keying chamber inspection dimensions .22
9 Alignment pin and/or electrical contact for front panels and plug-in units .23
9.1 Alignment pins and receptacle plates on the subrack horizontal members .24
9.2 Alignment and/or electrical contact pins and receptacles on the subrack
plug-in unit guides.25
10 Electrostatic discharge provision for plug-in units and subracks.27
10.1 ESD contact interface dimensions .28
10.2 ESD strip interface dimensions.28
11 Subrack dimensions for rear-mounted plug-in units .32

Annex A Subrack, plug-in unit and backplane dimensions for using metric connectors.33

Figure 1 – Typical example of large subracks in a wide cabinet, equipped mass
volume of copper/optical cables installation .7
Figure 2 – Subject for development of extended connector application packaging and
key elements of interconnection between functional plug-in modules via backplane in
the future packaging system .7
Figure 3 – Arrangement overview .9
Figure 4 – Subrack interface dimensions, injector/extractor handles for plug-in units .11
Figure 5 – Detail X and detail Y, subrack interface dimensions, injection/extraction
handles for plug-in units.12
Figure 6 – Plug-in units interface dimensions, injection/extraction handle for plug-in units .13
Figure 7 – Detail X and detail Y, plug-in interface dimensions, injector/extractor
handles for plug-in units.14
Figure 8 – Subrack interface dimensions, electromagnetic shielding provisions .15

60917-2-3  IEC:2006(E) – 3 –
Figure 9 – Detail X and detail Y, subrack interface dimensions, electromagnetic
shielding provisions .16
Figure 10 – Front panel/plug-in unit interface dimensions, electromagnetic shielding
provisions .17
Figure 11 – Arrangement of key/coding system for plug-in units.18
Figure 12 – Subrack interface dimensions – Key/coding system on the plug-in unit
guides.19
Figure 13 – Plug-in unit interface dimensions – Key/coding system on the plug-in unit
guides.20
Figure 14 – Key dimensions and rotated key positions – Key/coding system on the
plug-in unit guides .21
Figure 15 – Programming of keys .22
Figure 16 – Arrangement of alignment pin system for subracks and plug-in units.23
Figure 17 – Subrack interface dimensions, alignment pins and receptacle plates on
the horizontal members .24
Figure 18 – Plug-in unit interface dimensions, alignment pins and receptacle plates on
the horizontal members .25
Figure 19 – Subrack interface dimensions, alignment and/or electrical contact pin
receptacles on the plug-in unit guides.26
Figure 20 – Plug-in unit interface dimensions, alignment and/or electrical contact pin
receptacles on the plug-in unit guides.27
Figure 21 – Subrack interface dimensions, ESD contacts on the plug-in guides .28
Figure 22 – Plug-in unit interface dimensions, ESD strips on the plug-in boards .29
Figure 23 – Subrack dimensions for rear mounted plug-in units .32
Figure A.1 – Subrack, plug-in unit and backplane dimensions for using 2,5 mm metric
connectors in accordance with IEC 61076-4-100.33
Figure A.2 – Subrack, plug-in unit and backplane dimensions for using 2 mm metric
connectors in accordance with IEC 61076-4-101.34
Figure A.3 – Subrack, plug-in unit and backplane dimensions for using 2 mm metric
connectors in accordance with IEC 61076-4-104.35

Table 1 – Inspection dimensions of subrack and plug-in unit keying chambers.22
Table 2 – Dimensions of subracks and plug-in units based on IEC 60917-2-2 .30
Table 3 – Dimensions of subracks and boards for rear-mounted plug-in units .32

– 4 – 60917-2-3  IEC:2006(E)
INTERNATIONAL ELECTROTECHNICAL COMMISION
___________
MODULAR ORDER FOR THE DEVELOPMENT
OF MECHANICAL STRUCTURES
FOR ELECTRONIC EQUIPMENT PRACTICES –

Part 2-3: Sectional specification – Interface co-ordination dimensions
for the 25 mm equipment practice – Extended detail specification –
Dimensions for subracks, chassis, backplanes, front panels
and plug-in units
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,
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patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 60917-2-3 has been prepared by subcommittee 48D: Mechanical
structures for electronic equipment, of IEC technical committee 48: Electromechanical
components and mechanical structures for electronic equipment.
The text of this standard is based on following documents:
FDIS Report on voting
48D/338/FDIS 48D/342/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.

60917-2-3  IEC:2006(E) – 5 –
IEC 60917 consists of the following parts, under the general title Modular order for the
development of mechanical structures for electronic equipment practices:
Part 1: Generic standard
Part 2: Sectional specification – Interface co-ordination dimensions for the 25 mm
equipment practice
Part 2-1: Sectional specification – Interface co-ordination dimensions for the 25 mm
equipment practice – Detail specification – Dimensions for cabinets and racks
Part 2-2: Sectional specification – Interface co-ordination dimensions for the 25 mm
equipment practice – Detail specification – Dimensions for subracks, chassis,
backplanes, front panels and plug-in units
Part 2-3: Sectional specification – Interface co-ordination dimensions for the 25 mm
equipment practice – Extended detail specification – Dimensions for subracks,
chassis, backplanes, front panels and plug-in units
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result 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.
A bilingual version of this publication may be issued at a later date.

– 6 – 60917-2-3  IEC:2006(E)
INTRODUCTION
The dimensions in the detail specification for the 25 mm equipment practice standard are laid
down in the IEC 60917-2 series.
Significant progress in electronics circuitry, with increasing signal speed and the demand for
high availability of the electronics systems, has made an impact on the structural parts of the
equipment, as specified in IEC 60917-2-2.
a) Considerations on the general tendency of the enclosure system
At the moment, the general tendencies of the enclosure system for telecom/IT equipment
application and associated application are considered to be:
– the changing form of conventional centralized networking for telecommunication to
flexible distributed networking to realize ubiquitous communication and computing
environment by broad-band/IP and photonics-networking-based technology;
– flexible configuration of networking equipment from the open market is requested;
– a scalable and high-performance packaging/enclosure system is requested for new
networking equipment;
– in addition, such a packaging/enclosure system will be widely applied for general
electronic equipment, because IP networking technology is becoming one of the
common interfaces for all of industrial systems.
Consequently, the following general requirements for the new enclosure system arise.
– Standard-based but various sized networking/IT equipment from the open market
should be installed in one cabinet (see figure 1).
– The mass volume of copper/optical cables from the equipment should be managed in
the cabinet.
– Networking/IT cabinets will be increasingly sited at general offices in enterprise
buildings rather than at traditional technical rooms in telecom-central offices.
In order to meet these market needs, the implementation of additional specified
dimensions for extended features based on IEC 60917-2-2 became necessary.
b) Subject for development of extended connector application packaging based on
IEC 60917 series
The existing IEC 60917 series, which is structured on the modular concept of 25 mm, is
based on the IEC standardized metric connector. However, the system packaging uses to
many non-standardized enhanced connectors, which are necessary to realize the system
functions and level of performance (see Figure 2).
NOTE IEC Subcommittee 48D, Working Group 2, reviews the trends in system packaging, in which key elements
are electrical/optical signal interfaces and connectors, as well as the general tendency of the new enclosure
system. From these aspects, the IEC Subcommittee 48D, Working Group 2 has recently developed IEC 60917-2-3
which will be applicable to system packaging for high-speed and other system applications in the near future.

60917-2-3  IEC:2006(E) – 7 –
IEC  681/06
Figure 1 – Typical example of large subracks in a wide cabinet,
equipped mass volume of copper/optical cables installation
Metal wired/fibre-optic
Rear plug-in
linked backplane or
module
middleplane
Internal interface
inter SMDs/BGAs
on the module
High density and
high speed
connector
Functional module
unit with high density
multi-chip module BGA
High speed fibre
optic connector
High density multi-chip
Front plug-in
module (3D structured IC
module
mounted functional
SMD/BGA unit)
IEC  682/06
Key
SMD: Surface Mount Device.
BGA: Ball Grid Array.
Figure 2 – Subject for development of extended connector application packaging
and key elements of interconnection between functional plug-in modules
via backplane in the future packaging system

– 8 – 60917-2-3  IEC:2006(E)
MODULAR ORDER FOR THE DEVELOPMENT
OF MECHANICAL STRUCTURES
FOR ELECTRONIC EQUIPMENT PRACTICES –

Part 2-3: Sectional specification – Interface co-ordination dimensions
for the 25 mm equipment practice – Extended detail specification –
Dimensions for subracks, chassis, backplanes, front panels
and plug-in units
1 Scope and object
This part of IEC 60917 provides additional dimensions for a modular range of subracks and
associated plug-in units based on IEC 60917-2-2.
A typical subrack consists of a frame design with mounting dimensions for installation into
racks or cabinets in accordance with IEC 60917-2-1. The aperture dimensions of a subrack
are specified in order to meet the mounting dimensions of front plug-in units.
This part of IEC 60917 comprises
– additional dimensions for subracks and subrack associated plug-in units with injector/
extractor handle;
– dimensions for basic electromagnetic shielding provisions;
– dimensions of the key/coding system for subrack and plug-in units;
– dimensions of the alignment pin for front panel and plug-in unit;
– dimensions of electrostatic discharge provisions;
– dimensions of rear-mounted plug-in units.
Connector-related dimensions are given in Annex A.
In order to ensure the compatibility of plug-in units into the subrack, inspection dimensions
and connector-dependent dimensions are defined.
NOTE The drawings used in this part of IEC 60917 are not intended to indicate product design, only the specific
dimensions that are used.
2 Normative references
The following referenced documents are indispensable for the application of this document.
For dated references, only the edition cited applies. For undated references, the latest edition
of the referenced document (including any amendments) applies.
IEC 60917-1:1998, Modular order for the development of mechanical structures for electronic
equipment practices – Part 1: Generic standard
IEC 60917-2-1:1993, Modular order for the development of mechanical structures for
electronic equipment practice – Part 2: Sectional specification – Interface co-ordination
dimensions for the 25 mm equipment practice – Section 1: Detail specification – Dimensions
for cabinets and racks
IEC 60917-2-2:1994, Modular order for the development of mechanical structures for
electronic equipment practice – Part 2: Sectional specification – Interface co-ordination
dimensions for the 25 mm equipment practice – Section 2: Detail specification – Dimensions
for subracks, chassis, backplanes, front panels and plug-in units

60917-2-3  IEC:2006(E) – 9 –
IEC 61076-4-100:2001, Connectors for electronic equipment – Part 4-100: Printed board
connectors with assessed quality – Detail specification for two-part connector modules having
a grid of 2,5 mm for printed boards and backplanes
IEC 61076-4-101:2001, Connectors for electronic equipment – Part 4-101: Printed board
connectors with assessed quality – Detail specification for two-part connector modules,
having a basic grid of 2,0 mm for printed boards and backplane in accordance with IEC 60917
IEC 61076-4-104:1999, Connectors for use in d.c., low frequency analogue and digital high
speed data application – Part 4-104: Printed board connectors with assessed quality – Detail
specification for two-part modular connectors, basic grid of 2,0 mm, with terminations on a
multiple grid of 0,5 mm
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60917-1 apply.
4 Arrangement overview
Typical subrack with front and rear plug-in units (see Figure 3).

Typical rear
plug-in unit
Typical front
plug-in unit
Side
panel
Printed
board
Typical backplane/
middleplane
Front panel
Typical subrack
mounting flange
Typical plug-in unit
Typical injector/extractor
guide with subrack
handle mounted on
key chamber and
front panel
Typical horizontal member
alignment and/or
for injector/extractor handle
earth pin receptacle
IEC  683/06
Figure 3 – Arrangement overview

– 10 – 60917-2-3  IEC:2006(E)
5 Subrack dimensions for injector/extractor handle of plug-in units
5.1 Subrack interface dimensions
The following subrack interface dimensions shall be used only for applications with enhanced
injector/extractor handles that are defined in Clause 6 of this part of IEC 60917.
The basic dimensions of the subrack are in accordance with IEC 60917-2-2. Only the
additional dimensions of the subrack and plug-in units with the injector/extractor handles are
specified in this clause (see Figures 4 and 5).

60917-2-3  IEC:2006(E) – 11 –
Dimensions in millimetres
Front view, 6mp (6SU) high subrack
Section B-B
(W )
S0
(W )
S2 (D )
S1
(W ) (D )
S3 S2
(W )
S1
B
B
Backplane
Y
Section A-A
Rear
Front
horizontal
horizontal
First
member
member
pitch
line
Side panel
X
5 Subrack mounting flange
(W )
S1
Front view, 12mp (12SU) high subrack
Section B'-B'
B'
Backplane
Rear
B' Front
horizontal
Y
horizontal
(W )
S1
member
member
(W )
S3
(D )
S2
(W )
S2
(D )
S1
(W )
S0
IEC  684/06
NOTE Dimensions in parentheses are in accordance with IEC 60917-2-2 (see Table 2).
Figure 4 – Subrack interface dimensions, injector/extractor handles for plug-in units

(H )
S0 (H )
S0
(H ) (H )
S7
S7
(H )
(H )
S5
S5
A
A
(H ) (H )
S1 S1
A A
(H )
(H )
S7
S7
– 12 – 60917-2-3  IEC:2006(E)

Dimensions in millimetres
3,5
First
pitch
line
Detail X
Detail Y
IEC  685/06
NOTE Dimensions in parentheses are in accordance with IEC 60917-2-2 (see Table 2).
Figure 5 – Detail X and detail Y, subra
...

IEC 60917-2-3 ®
Edition 1.0 2006-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Modular order for the development of mechanical structures for electronic
equipment practices –
Part 2-3: Sectional specification – Interface co-ordination dimensions for
the 25 mm equipment practice – Extended detail specification – Dimensions
for subracks, chassis, backplanes, front panels and plug-in units

Ordre modulaire pour le développement des structures mécaniques pour les
infrastructures électroniques –
Partie 2-3: Spécification intermédiaire – Dimensions de coordination pour
les interfaces des infrastructures au pas de 25 mm – Spécification particulière
étendue – Dimensions pour bacs, châssis, fonds de paniers, faces avant et
unités enfichables
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IEC 60917-2-3 ®
Edition 1.0 2006-05
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
colour
inside
Modular order for the development of mechanical structures for electronic

equipment practices –
Part 2-3: Sectional specification – Interface co-ordination dimensions for

the 25 mm equipment practice – Extended detail specification – Dimensions

for subracks, chassis, backplanes, front panels and plug-in units

Ordre modulaire pour le développement des structures mécaniques pour les

infrastructures électroniques –

Partie 2-3: Spécification intermédiaire – Dimensions de coordination pour

les interfaces des infrastructures au pas de 25 mm – Spécification particulière

étendue – Dimensions pour bacs, châssis, fonds de paniers, faces avant et

unités enfichables
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
CODE PRIX V
ICS 31.240 ISBN 978-2-83220-885-4

– 2 – 60917-2-3  IEC:2006
CONTENTS
FOREWORD . 4
INTRODUCTION . 6

1 Scope and object . 8
2 Normative references . 8
3 Terms and definitions . 9
4 Arrangement overview . 9
5 Subrack dimensions for injector/extractor handle of plug-in units . 10
5.1 Subrack interface dimensions . 10
6 Dimensions of injector/extractor handle for plug-in units . 12
6.1 Injector/extractor handle interface dimensions . 12
6.2 Handle-locking function . 14
7 Subrack and plug-in units with electromagnetic shielding provision . 14
7.1 Subrack interface dimensions for electromagnetic shielding provision . 14
7.2 Front panel/plug-in unit interface dimensions . 17
8 Key/coding system for subrack and plug-in units . 18
8.1 General . 18
8.2 Subrack interface dimensions – Key/coding system on the plug-in unit guides . 19
8.3 Key dimensions – Key/coding system on the plug-in unit guides . 20
8.4 Programming of key – Key/coding system on the plug-in guides . 22
8.5 Keying chamber inspection dimensions . 22
9 Alignment pin and/or electrical contact for front panels and plug-in units . 23
9.1 General . 23
9.2 Alignment pins and receptacle plates on the subrack horizontal members . 24
9.3 Alignment and/or electrical contact pins and receptacles on the subrack
plug-in unit guides . 25
10 Electrostatic discharge provision for plug-in units and subracks. 27
10.1 General . 27
10.2 ESD contact interface dimensions . 28
10.3 ESD strip interface dimensions . 28
10.4 Dimensions of subracks and plug-in units based on IEC 60917-2-2 . 30
11 Subrack dimensions for rear-mounted plug-in units . 32
Annex A (informative) Subrack, plug-in unit and backplane dimensions for using
metric connectors . 33

Figure 1 – Typical example of large subracks in a wide cabinet, equipped mass

volume of copper/optical cables installation . 7
Figure 2 – Subject for development of extended connector application packaging and
key elements of interconnection between functional plug-in modules via backplane in
the future packaging system . 7
Figure 3 – Arrangement overview . 9
Figure 4 – Subrack interface dimensions, injector/extractor handles for plug-in units . 11
Figure 5 – Detail X and detail Y, subrack interface dimensions, injection/extraction
handles for plug-in units . 12
Figure 6 – Plug-in units interface dimensions, injection/extraction handle for plug-in units . 13

60917-2-3  IEC:2006 – 3 –
Figure 7 – Detail X and detail Y, plug-in interface dimensions, injector/extractor
handles for plug-in units . 14
Figure 8 – Subrack interface dimensions, electromagnetic shielding provisions . 15
Figure 9 – Detail X and detail Y, subrack interface dimensions, electromagnetic
shielding provisions . 16
Figure 10 – Front panel/plug-in unit interface dimensions, electromagnetic shielding
provisions . 17
Figure 11 – Arrangement of key/coding system for plug-in units . 18
Figure 12 – Subrack interface dimensions – Key/coding system on the plug-in unit
guides . 19
Figure 13 – Plug-in unit interface dimensions – Key/coding system on the plug-in unit
guides . 20
Figure 14 – Key dimensions and rotated key positions – Key/coding system on the
plug-in unit guides . 21
Figure 15 – Programming of keys . 22
Figure 16 – Arrangement of alignment pin system for subracks and plug-in units . 23
Figure 17 – Subrack interface dimensions, alignment pins and receptacle plates on
the horizontal members . 24
Figure 18 – Plug-in unit interface dimensions, alignment pins and receptacle plates on
the horizontal members . 25
Figure 19 – Subrack interface dimensions, alignment and/or electrical contact pin
receptacles on the plug-in unit guides . 26
Figure 20 – Plug-in unit interface dimensions, alignment and/or electrical contact pin
receptacles on the plug-in unit guides . 27
Figure 21 – Subrack interface dimensions, ESD contacts on the plug-in guides . 28
Figure 22 – Plug-in unit interface dimensions, ESD strips on the plug-in boards . 29
Figure 23 – Subrack dimensions for rear mounted plug-in units . 32
Figure A.1 – Subrack, plug-in unit and backplane dimensions for using 2,5 mm metric
connectors in accordance with IEC 61076-4-100 . 33
Figure A.2 – Subrack, plug-in unit and backplane dimensions for using 2 mm metric
connectors in accordance with IEC 61076-4-101 . 34
Figure A.3 – Subrack, plug-in unit and backplane dimensions for using 2 mm metric
connectors in accordance with IEC 61076-4-104 . 35

Table 1 – Inspection dimensions of subrack and plug-in unit keying chambers . 22
Table 2 – Dimensions of subracks and plug-in units based on IEC 60917-2-2 . 30
Table 3 – Dimensions of subracks and boards for rear-mounted plug-in units . 32

– 4 – 60917-2-3  IEC:2006
INTERNATIONAL ELECTROTECHNICAL COMMISION
___________
MODULAR ORDER FOR THE DEVELOPMENT
OF MECHANICAL STRUCTURES
FOR ELECTRONIC EQUIPMENT PRACTICES –

Part 2-3: Sectional specification – Interface co-ordination dimensions
for the 25 mm equipment practice – Extended detail specification –
Dimensions for subracks, chassis, backplanes, front panels
and plug-in units
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, Publicly Available Specifications (PAS) and Guides (hereafter referred to as “IEC
Publication(s)”). Their preparation is entrusted to technical committees; any IEC National Committee interested
in the subject dealt with may participate in this preparatory work. International, governmental and non-
governmental organizations liaising with the IEC also participate in this preparation. IEC collaborates closely
with the International Organization for 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
interested IEC National Committees.
3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
Committees in that sense. While all reasonable efforts are made to ensure that the technical content of IEC
Publications is accurate, IEC cannot be held responsible for the way in which they are used or for any
misinterpretation by any end user.
4) In order to promote international uniformity, IEC National Committees undertake to apply IEC Publications
transparently to the maximum extent possible in their national and regional publications. Any divergence
between any IEC Publication and the corresponding national or regional publication shall be clearly indicated in
the latter.
5) IEC provides no marking procedure to indicate its approval and cannot be rendered responsible for any
equipment declared to be in conformity with an IEC Publication.
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
members of its technical committees and IEC National Committees for any personal injury, property damage or
other damage of any nature whatsoever, whether direct or indirect, or for costs (including legal fees) and
expenses arising out of the publication, use of, or reliance upon, this IEC Publication or any other IEC
Publications.
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 60917-2-3 has been prepared by subcommittee 48D: Mechanical
structures for electronic equipment, of IEC technical committee 48: Electromechanical
components and mechanical structures for electronic equipment.
This bilingual version (2013-06) corresponds to the monolingual English version, published in
2006-05.
60917-2-3  IEC:2006 – 5 –
The text of this standard is based on following documents:
FDIS Report on voting
48D/338/FDIS 48D/342/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.
The French version of this standard has not been voted upon.
IEC 60917 consists of the following parts, under the general title Modular order for the
development of mechanical structures for electronic equipment practices:
Part 1: Generic standard
Part 2: Sectional specification – Interface co-ordination dimensions for the 25 mm
equipment practice
Part 2-1: Sectional specification – Interface co-ordination dimensions for the 25 mm
equipment practice – Detail specification – Dimensions for cabinets and racks
Part 2-2: Sectional specification – Interface co-ordination dimensions for the 25 mm
equipment practice – Detail specification – Dimensions for subracks, chassis,
backplanes, front panels and plug-in units
Part 2-3: Sectional specification – Interface co-ordination dimensions for the 25 mm
equipment practice – Extended detail specification – Dimensions for subracks,
chassis, backplanes, front panels and plug-in units
The committee has decided that the contents of this publication will remain unchanged until
the maintenance result 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.
IMPORTANT – The 'colour inside' logo on the cover page of this publication indicates
that it contains colours which are considered to be useful for the correct
understanding of its contents. Users should therefore print this document using a
colour printer.
– 6 – 60917-2-3  IEC:2006
INTRODUCTION
The dimensions in the detail specification for the 25 mm equipment practice standard are laid
down in the IEC 60917-2 series.
Significant progress in electronics circuitry, with increasing signal speed and the demand for
high availability of the electronics systems, has made an impact on the structural parts of the
equipment, as specified in IEC 60917-2-2.
a) Considerations on the general tendency of the enclosure system
At the moment, the general tendencies of the enclosure system for telecom/IT equipment
application and associated application are considered to be:
– the changing form of conventional centralized networking for telecommunication to
flexible distributed networking to realize ubiquitous communication and computing
environment by broad-band/IP and photonics-networking-based technology;
– flexible configuration of networking equipment from the open market is requested;
– a scalable and high-performance packaging/enclosure system is requested for new
networking equipment;
– in addition, such a packaging/enclosure system will be widely applied for general
electronic equipment, because IP networking technology is becoming one of the
common interfaces for all of industrial systems.
Consequently, the following general requirements for the new enclosure system arise.
– Standard-based but various sized networking/IT equipment from the open market
should be installed in one cabinet (see figure 1).
– The mass volume of copper/optical cables from the equipment should be managed in
the cabinet.
– Networking/IT cabinets will be increasingly sited at general offices in enterprise
buildings rather than at traditional technical rooms in telecom-central offices.
In order to meet these market needs, the implementation of additional specified
dimensions for extended features based on IEC 60917-2-2 became necessary.
b) Subject for development of extended connector application packaging based on
IEC 60917 series
The existing IEC 60917 series, which is structured on the modular concept of 25 mm, is
based on the IEC standardized metric connector. However, the system packaging uses to
many non-standardized enhanced connectors, which are necessary to realize the system
functions and level of performance (see Figure 2).
NOTE IEC Subcommittee 48D, Working Group 2, reviews the trends in system packaging, in which key elements
are electrical/optical signal interfaces and connectors, as well as the general tendency of the new enclosure
system. From these aspects, the IEC Subcommittee 48D, Working Group 2 has recently developed IEC 60917-2-3
which will be applicable to system packaging for high-speed and other system applications in the near future.

60917-2-3  IEC:2006 – 7 –
IEC  681/06
Figure 1 – Typical example of large subracks in a wide cabinet,
equipped mass volume of copper/optical cables installation
Metal wired/fibre-optic
Rear plug-in
linked backplane or
module
middleplane
Internal interface
inter SMDs/BGAs
on the module
High density and
high speed
connector
Functional module
unit with high density
multi-chip module BGA
High speed fibre
optic connector
High density multi-chip
Front plug-in
module (3D structured IC
module
mounted functional
SMD/BGA unit)
IEC  682/06
Key
SMD: Surface Mount Device.
BGA: Ball Grid Array.
Figure 2 – Subject for development of extended connector application packaging
and key elements of interconnection between functional plug-in modules
via backplane in the future packaging system

– 8 – 60917-2-3  IEC:2006
MODULAR ORDER FOR THE DEVELOPMENT
OF MECHANICAL STRUCTURES
FOR ELECTRONIC EQUIPMENT PRACTICES –

Part 2-3: Sectional specification – Interface co-ordination dimensions
for the 25 mm equipment practice – Extended detail specification –
Dimensions for subracks, chassis, backplanes, front panels
and plug-in units
1 Scope and object
This part of IEC 60917 provides additional dimensions for a modular range of subracks and
associated plug-in units based on IEC 60917-2-2.
A typical subrack consists of a frame design with mounting dimensions for installation into
racks or cabinets in accordance with IEC 60917-2-1. The aperture dimensions of a subrack
are specified in order to meet the mounting dimensions of front plug-in units.
This part of IEC 60917 comprises
– additional dimensions for subracks and subrack associated plug-in units with injector/
extractor handle;
– dimensions for basic electromagnetic shielding provisions;
– dimensions of the key/coding system for subrack and plug-in units;
– dimensions of the alignment pin for front panel and plug-in unit;
– dimensions of electrostatic discharge provisions;
– dimensions of rear-mounted plug-in units.
Connector-related dimensions are given in Annex A.
In order to ensure the compatibility of plug-in units into the subrack, inspection dimensions
and connector-dependent dimensions are defined.
NOTE The drawings used in this part of IEC 60917 are not intended to indicate product design, only the specific
dimensions that are used.
2 Normative references
The following referenced documents are indispensable for the application of this document.
For dated references, only the edition cited applies. For undated references, the latest edition
of the referenced document (including any amendments) applies.
IEC 60917-1:1998, Modular order for the development of mechanical structures for electronic
equipment practices – Part 1: Generic standard
IEC 60917-2-1:1993, Modular order for the development of mechanical structures for
electronic equipment practice – Part 2: Sectional specification – Interface co-ordination
dimensions for the 25 mm equipment practice – Section 1: Detail specification – Dimensions
for cabinets and racks
IEC 60917-2-2:1994, Modular order for the development of mechanical structures for
electronic equipment practice – Part 2: Sectional specification – Interface co-ordination
dimensions for the 25 mm equipment practice – Section 2: Detail specification – Dimensions
for subracks, chassis, backplanes, front panels and plug-in units

60917-2-3  IEC:2006 – 9 –
IEC 61076-4-100:2001, Connectors for electronic equipment – Part 4-100: Printed board
connectors with assessed quality – Detail specification for two-part connector modules having
a grid of 2,5 mm for printed boards and backplanes
IEC 61076-4-101:2001, Connectors for electronic equipment – Part 4-101: Printed board
connectors with assessed quality – Detail specification for two-part connector modules,
having a basic grid of 2,0 mm for printed boards and backplane in accordance with IEC 60917
IEC 61076-4-104:1999, Connectors for use in d.c., low frequency analogue and digital high
speed data application – Part 4-104: Printed board connectors with assessed quality – Detail
specification for two-part modular connectors, basic grid of 2,0 mm, with terminations on a
multiple grid of 0,5 mm
3 Terms and definitions
For the purposes of this document, the terms and definitions given in IEC 60917-1 apply.
4 Arrangement overview
Typical subrack with front and rear plug-in units (see Figure 3).

Typical rear
plug-in unit
Typical front
plug-in unit
Side
panel
Printed
board
Typical backplane/
middleplane
Front panel
Typical subrack
mounting flange
Typical plug-in unit
Typical injector/extractor
guide with subrack
handle mounted on
key chamber and
front panel
Typical horizontal member
alignment and/or
for injector/extractor handle
earth pin receptacle
IEC  683/06
Figure 3 – Arrangement overview

– 10 – 60917-2-3  IEC:2006
5 Subrack dimensions for injector/extractor handle of plug-in units
5.1 Subrack interface dimensions
The following subrack interface dimensions shall be used only for applications with enhanced
injector/extractor handles that are defined in Clause 6 of this part of IEC 60917.
The basic dimensions of the subrack are in accordance with IEC 60917-2-2. Only the
additional dimensions of the subrack and plug-in units with the injector/extractor handles are
specified in this clause (see Figures 4 and 5).

60917-2-3  IEC:2006 – 11 –
Dimensions in millimetres
Front view, 6mp (6SU) high subrack
Section B-B
(W )
S0
(W )
S2 (D )
S1
(W )
(D )
S3 S2
(W )
S1
B
B
Backplane
Y
Section A-A
Rear
Front
horizontal
horizontal
First
member
member
pitch
line
Side panel
X
5 Subrack mounting flange
(W )
S1
Front view, 12mp (12SU) high subrack
Section B'-B'
B'
Backplane
Rear
B' Front
horizontal
Y
horizontal
(W )
S1 member
member
(W )
S3
(D )
S2
(W )
S2
(D )
S1
(W )
S0
IEC  684/06
NOTE Dimensions in parentheses are in accordance with IEC 60917-2-2 (see Table 2).
Figure 4 – Subrack interface dimensions, injector/extractor handles for plug-in units

(H )
(H )
S0
S0
(H ) (H )
S7
S7
(H ) (H )
S5
S5
A
A
(H ) (H )
S1 S1
A A
(H )
(H )
S7
S7
– 12 – 60917-2-3  IEC:2006
Dimensions in millimetres
3,5
First
pitch
line
Detail X
Detail Y
IEC  685/06
NOTE Dimensions in parentheses are in accordance with IEC 60917-2-2 (see Table 2).
Figure 5 – Detail X and detail Y, subrack interface dimensions,
injection/extraction handles for plug-in units
6 Dimensions of injector/extractor handle for plug-in units
6.1 Injector/extractor handle interface dimensions
The following handle interface dimensions shall be used only for applications with subracks
that have the interface dimensions for injector/extractor handles and that are defined in
Clause 5 of this part of IEC 60917.
The basic dimensions of the plug-in units are in accordance with IEC 60917-2-2. Only the
additional dimensions of the plug-in units with the injector/extractor handles are specified in
this clause (see Figures 6 and 7).
The width of the injector/extractor handles can have any dimension less than Ws4, front panel
width. See Table 2b.
The injector/extractor handles may exceed the horizontal pitch lines defined in 60917-2-2 to
obtain effective injection/extraction function. The handle in closed position shall not exceed
the subrack reference plane. In operation of insertion and extraction, the handle may exceed
by maximum 0,5 mp 1 (0,5 SU) to the subrack (height) reference plane on both sides, top and
bottom.
NOTE It is recommended that, in respect to the connector insertion/withdrawal force, the handle should be of
such a design, that the force to operate the handle should not exceed 100 N.
>8
13,3
18,3
(H )
S0
(H )
S7
(H )
S5
(H )
S1
60917-2-3  IEC:2006 – 13 –
Dimensions in millimetres
Plug-in unit front view, Plug-in unit side view,
for 6mp (6SU) high subrack for 6mp (6SU) high subrack
1 1
Font panel
Printed board
Y
X
Injector/ Injector/
Injector/
(D )
extractor extractor
S4 extractor
(W )
S4
handle, handle,
handle
(W ) (D )
wide type S4 slim type S1
Plug-in unit front view, Plug-in unit side view,
for 12mp (12SU) and 18mp (18SU) high subrack for 12mp (12SU) and 18mp (18SU) high subrack
1 1 1 1
Injector/
Font panel extractor
handle
Printed board
X
Y
Injector/
Injector/
extractor Injector/
extractor
handle, handle, extractor
(D )
S3
S4
wide type slim type handle
(D )
(W ) S1
(W )
S4
S4
IEC  686/06
NOTE Dimensions in parentheses are in accordance with IEC 60917-2-2 (see Table 2).
Figure 6 – Plug-in units interface dimensions,
injection/extraction handle for plug-in units

(H ) (H )
S7
S8
(H )
S5
(H )
(H ) S3
S3
(H )
(H )
S13 S13
(H )
(H ) S14
S14
– 14 – 60917-2-3  IEC:2006
Dimensions in millimetres
Injector/
extractor
handle
Front panel
Printed board
Front panel
Printed board
mounting block
Printed board
Front panel
fixing screw
fixing screw
Injector/
Subrack horizontal
Subrack (height)
extractor Subrack horizontal
member
reference plane
handle member
(W ) ≤38
S4
Front panel
fixing screw
Detail X Detail Y
IEC  687/06
NOTE Dimensions in parentheses are in accordance with IEC 60917-2-2 (see Table 2).
Figure 7 – Detail X and detail Y, plug-in interface dimensions,
injector/extractor handles for plug-in units
6.2 Handle-locking function
The injector/extractor handle may have a locking function instead of a plug-in unit fixing screw.
7 Subrack and plug-in units with electromagnetic shielding provision
7.1 Subrack interface dimensions for electromagnetic shielding provision
The following subrack interface dimensions shall be used only for applications with plug-in
units that have electromagnetic shielding provisions as defined in 7.2 of this part of
IEC 60917.
The basic dimensions of the subrack are in accordance with IEC 60917-2-2 for subracks, front
panels and plug-in units. Only the additional dimensions of the subrack with the electro-
magnetic shielding provision are specified in this clause (see Figures 8 and 9).
The width of the injector/extractor handle can have any dimension less than W , front panel
s4
width (see Table 2).
The injector/extractor handles may exceed the horizontal pitch lines defined in IEC 60917-2-2
to obtain effective injection/extraction function.
The handle in closed position shall not exceed the subrack reference plane. In the operations
of insertion and extraction, the handle may exceed the subrack (height) reference plane on
both sides, top and bottom by a maximum of 0,5 mp (0,5 SU).
(H )
S8
(H )
S5
(H )
S8
(H )
S3
(H )
S13
(H )
S14
≤75
60917-2-3  IEC:2006 – 15 –
Dimensions in millimetres
Front view
(W )
S1
Horizontal conductive
area with optional
shielding gasket
Section A-A
First
pitch
line
Vertical shielding gasket
Vertical shielding contact
X
Y
(W )
S1
IEC  688/06
NOTE Dimensions in parenthesis are in accordance with IEC 60917-2-2 (see Table 2).
Figure 8 – Subrack interface dimensions, electromagnetic shielding provisions

A
A
>2,0 >2,0
(H )
S1
– 16 – 60917-2-3  IEC:2006
Dimensions in millimetres
Vertical Vertical
shielding shielding
Detail X
Detail X
contact gasket
Centre line of
shielding gasket
1,0 max.
0,5 min.
Uncompressed
First
(W ) gasket
S1
pitch
line
IEC  689/06
NOTE 1 Dimensions in parentheses are in accordance with IEC 60917-2-2 (see Table 2).
NOTE 2 It is recommended that shielding gaskets and shielding contact surfaces of low electrical resistance and
long-lasting corrosion protection should be used.

Figure 9 – Detail X and detail Y, subrack interface dimensions,
electromagnetic shielding provisions
≥2,5
≥3,8
≥2,0
60917-2-3  IEC:2006 – 17 –
7.2 Front panel/plug-in unit interface dimensions
The following front panel/plug-in units interface dimensions shall be used only for applications
with subracks that have electromagnetic shielding provisions, as defined in 7.1 of this part of
IEC 60917.
The basic dimensions of the front panel/plug-in unit are in accordance with IEC 60917-2-2 for
subracks, front panels and plug-in units. Only the additional dimensions of the front
panel/plug-in unit with the electromagnetic shielding provision are specified in this clause (see
Figure 10).
Dimensions in millimetres
Front view Side view
Horizontal conductive
area at the rear
Vertical conductive/
gasket area
Pitch line for
Horizontal conductive
front panel
area at the rear
Top view
Gasket
n × 5
Centre line of
shielding gasket
1,0 max.
≤2,15
≥2,5
0,5 min.
≤1,15
Gasket travel
Uncompressed
gasket
IEC  690/06
NOTE Dimensions in parentheses are in accordance with IEC 60917-2-2 (see Table 2).
Figure 10 – Front panel/plug-in unit interface dimensions,
electromagnetic shielding provisions

(H )
S8
≥8,0 ≥8,0
≤3,8
2,5 ± 0,25
≥16,0 ≥16,0
(H )
S5
– 18 – 60917-2-3  IEC:2006
8 Key/coding system for subrack and plug-in units
8.1 General
The subrack and plug-in units may have a key/coding system on the plug-in unit and the
subrack plug-in unit guide. This part of IEC 60917 details a keying system that is user-
programmable from the front and/or the rear of a subrack and on the rear face of a plug-in
unit. The programmable key can be set, removed or changed by the users (see Figures 11, 12
and 13).
A subrack assembled with guide rails in accordance with IEC 60917-2-2 and Clause 11 of this
part of IEC 60917 (without a keying feature) will accept plug-in units with front panels in
accordance with this clause (with keys removed).

Typical front/rear mounted
printed-board type
plug-in unit
Key
Printed board
Plug-in unit
mounted key
Subrack
mounted key
Typical front/rear mounted
plug-in unit guide
IEC  691/06
Figure 11 – Arrangement of key/coding system for plug-in units

60917-2-3  IEC:2006 – 19 –
8.2 Subrack interface dimensions – Key/coding system on the plug-in unit guides
Dimensions in millimetres
Side view
Front view
Cross section A-A
Plug-in unit
3× Plug-in
guide
unit guide
13 ± 0,3 ≥4,9
2×
□2,5 ± 0,05 3,1
–0,2
A
A
(2,5) Subrack Subrack
Subrack
horizontal key chamber
horizontal
key member
mp
2 Subrack
Pitch
horizontal
line
member
IEC  692/06
NOTE 1 For the H dimension, see Table 1.
SK
NOTE 2 Dimensions in parentheses are in accordance with IEC 60917-2-2 (see Table 2).
Figure 12 – Subrack interface dimensions –
Key/coding system on the plug-in unit guides

(H )
S5
H NOTE 1
SK
≥□3,3
– 20 – 60917-2-3  IEC:2006
Dimensions in millimetres
Injector/extractor handle
Front panel
Printed board
Subrack
mounted key
Plug-in
unit guide
Printed board
mounting block
□2,5 ± 0,05
Plug-in unit
3,1
–0,2
Subrack
key chamber
Plug-in unit
horizontal Subrack key
mounted key
4,75 ± 0,15
member chamber
IEC  693/06
NOTE 1 For the H dimension, see Table 1.
SK
NOTE 2 Dimensions in parentheses are in accordance with IEC 60917-2-2 (see Table 2).
Figure 13 – Plug-in unit interface dimensions –
Key/coding system on the plug-in unit guides
8.3 Key dimensions – Key/coding system on the plug-in unit guides
The key dimensions will allow the programming of four positions within one chamber of the
subrack and the plug-in units respectively. The keys shall be designed for self-retaining snap-
in assembly (see Figures 14 and 15).
The key chambers of the subracks and the plug-in units are identified by six letters; they are
A, B, C, D, E and F (see Figure 15). Subracks of 6 mp (6 SU) in height and associated plug-
in units typically provide the keying chambers in the lower position that are identified by three
letters, D, E and F. Subracks and plug-in units having a height of 12 mp (12 SU) and 18 mp
1 1
(18 SU) may have the keying chamber in the upper and lower positions that are identified by
six letters from A to F.
≥□3,3
H
SK NOTE 1
(H )
S5
≥□3,3
60917-2-3  IEC:2006 – 21 –
Dimensions in millimetres
0 Subrack/Plug-in unit
4,4
–0,1
key chamber
insertion part
Key block part
2,4
<4,6 7,6 ± 0,1
–0,05
Key rotated positions
Position 1 Position 2 Position 3 Position 4
IEC  694/06
Figure 14 – Key dimensions and rotated key positions –
Key/coding system on the plug-in unit guides

2,4
–0,05
2,1
≥0,1
–0,1
– 22 – 60917-2-3  IEC:2006
8.4 Programming of key – Key/coding system on the plug-in guides

Plug-in unit keying
Subrack keying front view
view on front panel rear side
1 2 3 4 N N 4 3 2 1
Subrack top
Plug-in unit top
keying positions,
A B C C B A
keying positions,
key chambers, A, B and C
key chambers, A, B and C
Printed board
Plug-in unit
front panel
Subrack bottom
Plug-in unit bottom
keying positions,
D E F F E D keying positions,
key chambers, D, E and F
key chambers, D, E and F
1 2 3 4 N N 4 3 2 1
IEC  695/06
NOTE 1 On the rear of the subrack/plug-in unit, the letters A, B and C will be on the bottom and D, E and F on the
top. The order of letters on the rear is a mirror image.
NOTE 2 Position marks show the key rotated position 1, 2, 3 and 4. "N" indicates a condition without key.
Figure 15 – Programming of keys
8.5 Keying chamber inspection dimensions
Table 1 contains the correct heights dimensions H , which will insure the alignment of the
SK
two counterparts of the keying inserts.
Table 1 – Inspection dimensions of subrack and plug-in unit keying chambers
Dimensions in millimetres
SU 6 12 18
(H B ) 150 300 450
S
H ± 0,3 121 271 421
SK
60917-2-3  IEC:2006 – 23 –
9 Alignment pin and/or electrical contact for front panels and plug-in units
9.1 General
The feature of the alignment and/or electrical contact is to align front panels in their position
within a subrack (for example, for the use of shielding gaskets, see Clause 7 of this part of
IEC 60917) or as a contact to the electrical receptacle on the subrack (see Figures 16, 17, 18
and 19).
Plug-in unit mounted alignment pin
Typical front/rear mounted
for the subrack horizontal member
printed-board type
plug-in unit
Printed board
Plug-in unit mounted
alignment and/or
electrical contact pin
Plug-in unit mounted alignment
Typical front/rear mounted
and/or electrical contact receptacle
plug-in unit guide
IEC  696/06
Figure 16 – Arrangement of alignment pin system for subracks and plug-in units

– 24 – 60917-2-3  IEC:2006
9.2 Alignment pins and receptacle plates on the subrack horizontal members
This alignment system shall be located at the area for the fastening arrangement between a
subrack and plug-in units in accordance with IEC 60917-2-2 and Clause 11 of this part of
IEC 60917. Therefore, in application of this alignment system, the plug-in units may have the
injector/extractor handles with a locking function in accordance with 6.2, instead of the fixing
by screws.
Dimensions in millimetres
Side view
Front view
Cross section A-A
3×
+0,3
0 Plug-in
Plug-in
2×
unit guide
unit guide
3,1 ± 0,15
3 ± 0,15
A
Threaded plate
A
with alignment
receptacle holes
Threaded plate
(2,5)
Subrack
mp
2 with alignment
∅2,8 ± 0,05 horizontal
Pitch
receptacle holes
member
Receptacle hole
line
for alignment pin
IEC  697/06
NOTE Dimensions in parentheses are in accordance with IEC 60917-2-2 (see Table 2).
Figure 17 – Subrack interface dimensions, alignment pins
and receptacle plates on the horizontal members

(H )
S5
+0,3
3,2
6,3 ± 0,2
60917-2-3  IEC:2006 – 25 –
D
...