IEC 60297-3-109:2015

Mechanical structures for electrical and electronic equipment - Dimensions of mechanical structures of the 482,6 mm (19 in) series - Part 3-109: Dimensions of chassis for embedded computing devices

IEC 60297-3-109:2015 specifies dimensions and physical properties of chassis and associated printed boards in order to provide mechanical and environmental integrity for embedded computing devices. They are used in various applications such as machine control, medical, transportation, aerospace and telecommunication, typically based on single board computers. For the easy definition of the suitable chassis and associated single board dimensions, this standard is based on a structural grid of 44,45 mm (1,75 in). Key words: Dimensions, Mechanical Structures, Chassis, Embedded Computing Devices

Structures mécaniques pour équipements électriques et électroniques - Dimensions des structures mécaniques de la série 482,6 mm (19 pouces) - Partie 3-109: Dimensions des châssis pour dispositifs informatiques intégrés

L'IEC 60297-3-109:2015 spécifie les dimensions et les propriétés physiques des châssis et des cartes imprimées associées, afin de garantir l'intégrité mécanique et environnementale des dispositifs informatiques intégrés. Ces derniers sont utilisés dans de nombreuses applications, notamment pour commander des machines dans les environnements de la santé, des transports, de l'aérospatial et des communications. Il s'agit généralement d'ordinateurs monocartes. Pour faciliter la définition des dimensions adaptées des châssis et cartes imprimées associées, la présente norme se base sur une grille structurelle de 44,45 mm (1,75 pouce). Mots-clés: Dimensions, Structures mécaniques, Châssis, Dispositifs informatiques intégrés

General Information

• Status: Published
• Publication Date: 22-Nov-2015
• ICS: 31.240 - Mechanical structures for electronic equipment
• Technical Committee: SC 48D - Mechanical structures for electrical and electronic equipment
• Drafting Committee: WG 4 - TC 48/SC 48D/WG 4
• Current Stage: PPUB - Publication issued
• Start Date: 23-Nov-2015
• Completion Date: 15-Dec-2015

Standards Content (Sample)

IEC 60297-3-109 ®
Edition 1.0 2015-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Mechanical structures for electrical and electronic equipment – Dimensions of
mechanical structures of the 482,6 mm (19 in) series –
Part 3-109: Dimensions of chassis for embedded computing devices

Structures mécaniques pour équipements électriques et électroniques –
Dimensions des structures mécaniques de la série 482,6 mm (19 pouces) –
Partie 3-109: Dimensions des châssis pour dispositifs informatiques intégrés

All rights reserved. Unless otherwise specified, 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
either IEC or IEC's member National Committee in the country of the requester. If you have any questions about IEC
copyright or have an enquiry about obtaining additional rights to this publication, please contact the address below or
your local IEC member National Committee for further information.

Droits de reproduction réservés. Sauf indication contraire, aucune partie de cette publication ne peut être reproduite
ni utilisée sous quelque forme que ce soit et par aucun procédé, électronique ou mécanique, y compris la photocopie
et les microfilms, sans l'accord écrit de l'IEC ou du Comité national de l'IEC du pays du demandeur. Si vous avez des
questions sur le copyright de l'IEC ou si vous désirez obtenir des droits supplémentaires sur cette publication, utilisez
les coordonnées ci-après ou contactez le Comité national de l'IEC de votre pays de résidence.

IEC Central Office Tel.: [phone]
3, rue de Varembé Fax: [phone]
CH-1211 Geneva 20 [e-mail]
Switzerland www.iec.ch
About the IEC
The International Electrotechnical Commission (IEC) is the leading global organization that prepares and publishes
International Standards for all electrical, electronic and related technologies.

About IEC publications
The technical content of IEC publications is kept under constant review by the IEC. Please make sure that you have the
latest edition, a corrigenda or an amendment might have been published.

IEC Catalogue - webstore.iec.ch/catalogue Electropedia - www.electropedia.org
The stand-alone application for consulting the entire The world's leading online dictionary of electronic and
bibliographical information on IEC International Standards, electrical terms containing more than 30 000 terms and
Technical Specifications, Technical Reports and other definitions in English and French, with equivalent terms in 15
documents. Available for PC, Mac OS, Android Tablets and additional languages. Also known as the International
iPad. Electrotechnical Vocabulary (IEV) online.

IEC publications search - www.iec.ch/searchpub IEC Glossary - std.iec.ch/glossary
The advanced search enables to find IEC publications by a More than 60 000 electrotechnical terminology entries in
variety of criteria (reference number, text, technical English and French extracted from the Terms and Definitions
committee,…). It also gives information on projects, replaced clause of IEC publications issued since 2002. Some entries
and withdrawn publications. have been collected from earlier publications of IEC TC 37,

77, 86 and CISPR.
IEC Just Published - webstore.iec.ch/justpublished
Stay up to date on all new IEC publications. Just Published IEC Customer Service Centre - webstore.iec.ch/csc
details all new publications released. Available online and If you wish to give us your feedback on this publication or
also once a month by email. need further assistance, please contact the Customer Service
Centre: [e-mail].
A propos de l'IEC
La Commission Electrotechnique Internationale (IEC) est la première organisation mondiale qui élabore et publie des
Normes internationales pour tout ce qui a trait à l'électricité, à l'électronique et aux technologies apparentées.

A propos des publications IEC
Le contenu technique des publications IEC est constamment revu. Veuillez vous assurer que vous possédez l’édition la
plus récente, un corrigendum ou amendement peut avoir été publié.

Catalogue IEC - webstore.iec.ch/catalogue Electropedia - www.electropedia.org
Application autonome pour consulter tous les renseignements
Le premier dictionnaire en ligne de termes électroniques et
bibliographiques sur les Normes internationales,
électriques. Il contient plus de 30 000 termes et définitions en
Spécifications techniques, Rapports techniques et autres
anglais et en français, ainsi que les termes équivalents dans
documents de l'IEC. Disponible pour PC, Mac OS, tablettes
15 langues additionnelles. Egalement appelé Vocabulaire
Android et iPad.
Electrotechnique International (IEV) en ligne.

Recherche de publications IEC - www.iec.ch/searchpub
Glossaire IEC - std.iec.ch/glossary
Plus de 60 000 entrées terminologiques électrotechniques, en
La recherche avancée permet de trouver des publications IEC
en utilisant différents critères (numéro de référence, texte, anglais et en français, extraites des articles Termes et
comité d’études,…). Elle donne aussi des informations sur les Définitions des publications IEC parues depuis 2002. Plus
projets et les publications remplacées ou retirées. certaines entrées antérieures extraites des publications des

CE 37, 77, 86 et CISPR de l'IEC.
IEC Just Published - webstore.iec.ch/justpublished

Service Clients - webstore.iec.ch/csc
Restez informé sur les nouvelles publications IEC. Just
Published détaille les nouvelles publications parues. Si vous désirez nous donner des commentaires sur cette
Disponible en ligne et aussi une fois par mois par email. publication ou si vous avez des questions contactez-nous:
[e-mail].
IEC 60297-3-109 ®
Edition 1.0 2015-11
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Mechanical structures for electrical and electronic equipment – Dimensions of

mechanical structures of the 482,6 mm (19 in) series –

Part 3-109: Dimensions of chassis for embedded computing devices

Structures mécaniques pour équipements électriques et électroniques –

Dimensions des structures mécaniques de la série 482,6 mm (19 pouces) –

Partie 3-109: Dimensions des châssis pour dispositifs informatiques intégrés

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 31.240 ISBN 978-2-8322-3007-7

– 2 – IEC 60297-3-109:2015 © IEC 2015
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope . 7
2 Normative references . 7
3 Terms and definitions . 7
4 Arrangement overview . 7
5 Chassis dimensions . 8
Annex A (normative) Printed board dimensions . 11
A.1 Illustrative figure . 11
A.2 Maximum printed board dimensions . 11
Annex B (normative) Printed board dimensions in conjunction with fan cooling . 13
B.1 Illustrative figure . 13
B.2 Maximum printed board dimensions in conjunction with fan cooling . 13
Annex C (normative) Chassis mounting options . 16
C.1 Type A: Example for 19” cabinet mounting option . 16
C.2 Type B: Example for 19” cabinet mounting option . 16
C.3 Type C: Chassis mounting example . 17
C.4 Type D: Chassis mounting option . 17
Annex D (normative) Environmental tests . 19
D.1 Static and dynamic load test . 19
D.2 Seismic test . 19
D.3 Electromagnetic shielding performance test . 19
D.4 Degrees of protection . 19
Annex E (informative) Extended chassis dimensions . 20
E.1 General . 20
E.2 Illustrative figure . 20
E.3 Extended chassis dimensions . 20

Figure 1 – Three dimensional grid for chassis and associated printed boards . 6
Figure 2 – Chassis arrangement of an embedded application . 8
Figure 3 – Chassis front dimensions . 8
Figure 4 – Chassis depth dimensions . 8
Figure A.1 – Chassis with printed board . 11
Figure A.2 – Printed board dimensions . 11
Figure B.1 – Chassis with fan cooling . 13
Figure B.2 – Printed board dimensions in conjunction with fan cooling, example (fan
depth = 28,0 mm) . 14
Figure C.1 – Type A: Chassis mounting in a 19” cabinet . 16
Figure C.2 – Type B: Chassis mounting in a 19” cabinet . 17
Figure C.3 – Type C: Vertical flange mounting . 17
Figure C.4 – Type D: Horizontal flange mounting . 18
Figure E.1 – Extended chassis example . 20
Figure E.2 – Extended chassis – front dimensions . 20

Figure E.3 – Extended chassis – depth dimensions. 21

Table 1 – Chassis height dimensions . 9
Table 2 – Chassis width dimensions . 9
Table 3 – Chassis depth dimensions . 10
Table A.1 – Printed board width dimensions . 12
Table A.2 – Printed board depth dimensions . 12
Table B.1 – Printed board width dimensions in conjunction with fan cooling, example
(fan depth=28,0 mm) . 15

– 4 – IEC 60297-3-109:2015 © IEC 2015
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MECHANICAL STRUCTURES FOR ELECTRICAL AND
ELECTRONIC EQUIPMENT – DIMENSIONS OF MECHANICAL
STRUCTURES OF THE 482,6 mm (19 in) SERIES –

Part 3-109: Dimensions of chassis for embedded computing devices

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 itself does not provide any attestation of conformity. Independent certification bodies provide conformity
assessment services and, in some areas, access to IEC marks of conformity. IEC is not responsible for any
services carried out by independent certification bodies.
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 60297-3-109 has been prepared by subcommittee 48D:
Mechanical structures for electrical and electronic equipment, of IEC technical committee 48:
Electrical connectors and mechanical structures for electrical and electronic equipment.
The text of this standard is based on the following documents:
FDIS Report on voting
48D/598/FDIS 48D/602/RVD
Full information on the voting for the approval of this standard can be found in the report on
voting indicated in the above table.
This publication has been drafted in accordance with the ISO/IEC Directives, Part 2.

A list of all parts in the IEC 60297-3 series, published under the general title Mechanical
structures for electrical and electronic equipment – Dimensions of mechanical structures of
the 482,6 mm (19 in) series, can be found on the IEC website.
Future standards in this series will carry the new general title as cited above. Titles of existing
standards in this series will be updated at the time of the next edition.
The committee has decided that the contents of this publication will remain unchanged until
the stability date indicated on the IEC website 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.
– 6 – IEC 60297-3-109:2015 © IEC 2015
INTRODUCTION
The main applications for embedded computing devices are in machine control, medical,
transportation, aerospace and communication environments. For such applications single
board computers are typically used.
In order to meet the different environmental conditions and handling requirements, single
board computers require for mechanical, thermal and environmental protection by means of
appropriate chassis designs. These devices currently reflect a very fragmented situation in
the view of any existing mechanical structures dimensional standard. Due to the lack of
standardization the individual solutions are realized with proprietary dimensions.
The rapidly growing market for single board computing devices calls for dimensional
coordination of chassis and associated printed boards, in order to replace proprietary
solutions. This standard will establish a three dimensional grid of 44,45 mm (1,75 in) for
chassis and the associated printed boards, which meets best the most frequent dimensional
environment of the IEC 60297 series. Once this standard is established, the design and
manufacturing of embedded computing solutions will gain significant cost efficiency.
n x 44,45 mm
n x 44,45 mm
IEC
Figure 1 – Three dimensional grid for chassis and associated printed boards

n x 44,45 mm
MECHANICAL STRUCTURES FOR ELECTRICAL AND
ELECTRONIC EQUIPMENT – DIMENSIONS OF MECHANICAL
STRUCTURES OF THE 482,6 mm (19 in) SERIES –

Part 3-109: Dimensions of chassis for embedded computing devices

1 Scope
This part of IEC 60297 specifies dimensions and physical properties of chassis and
associated printed boards in order to provide mechanical and environmental integrity for
embedded computing devices. They are used in various applications such as machine control,
medical, transportation, aerospace and telecommunication, typically based on single board
computers.
For the easy definition of the suitable chassis and associated single board dimensions, this
standard is based on a structural grid of 44,45 mm (1,75 in).
2 Normative references
The following documents, in whole or in part, are normatively referenced in this document and
are indispensable for its application. For dated references, only the edition cited applies. For
undated references, the latest edition of the referenced document (including any
amendments) applies.
IEC 60297-3-100, Mechanical structures for electronic equipment – Dimensions of mechanical
structures of the 482,6 mm (19 in) series – Part 3-100: Basic dimensions of front panels,
subracks, chassis, racks and cabinets
IEC 60529, Degrees of protection provided by enclosures (IP Code)
IEC 61587-1, Mechanical structures for electronic equipment – Tests for IEC 60917 and IEC
60297 series – Part 1: Environmental requirements, test set-up and safety aspects for
cabinets, racks, subracks and chassis under indoor conditions
IEC 61587-3, Mechanical structures for electronic equipment – Tests for IEC 60917 and IEC
60297 – Part 3: Electromagnetic shielding performance tests for cabinets and subracks
IEC 61587-5, Mechanical structures for electronic equipment – Tests for IEC 60917 and IEC
60297 – Part 5: Seismic tests for chassis, subracks and plug-in units
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
chassis for embedded computing
mechanical structure designed to support associated electric and electronic components
4 Arrangement overview
Figure 2 illustrates a typical chassis arrangement.

– 8 – IEC 60297-3-109:2015 © IEC 2015
Chassis
Printed board
I/O
(Input/output)
IEC
Figure 2 – Chassis arrangement of an embedded application
5 Chassis dimensions
The chassis dimensions are based on a structural grid of 44,45 mm (1,75 in). Figure 3 and
Figure 4 illustrate the chassis width, height and depth dimensions. See also Tables 1 to 3.
Dimensions in millimetres
A
W1
n x 44,45
IEC
Figure 3 – Chassis front dimensions
Dimensions in millimetres
View A
n x 44,45
D1
IEC
Figure 4 – Chassis depth dimensions
n x 44,45
H1
Table 1 – Chassis height dimensions
Height units H1
n × U ±0,4
(n × 44,45)
1U
(44,45) 43,65
2U
(88,90) 88,10
3U
(133,35) 132,55
4U
(177,80) 177,00
5U
(222,25) 221,45
Table 2 – Chassis width dimensions
Width units W1
n × W ±0,4
(n × 44,45)
3W
(133,35) 132,55
4W
(177,80) 177,00
5W
(222,25) 221,45
6W
(266,70) 265,90
7W
(311,15) 310,35
8W
(355,60) 354,80
9W
(400,05) 399,25
10W
(444,50) 443,70
– 10 – IEC 60297-3-109:2015 © IEC 2015
Table 3 – Chassis depth dimensions
Depth units D1
n × D ±0,4
(n × 44,45)
3D
(133,35) 132,55
4D
(177,80) 177,00
5D
(222,25) 221,45
6D
(266,70) 265,90
7D
(311,15) 310,35
8D
(355,60) 354,80
9D
(400,05) 399,25
10D
(444,50) 443,70
Annex A
(normative)
Printed board dimensions
A.1 Illustrative figure
Figure A.1 illustrates the chassis with the associated printed board.
Chassis
Printed board
A A
W1
IEC
Figure A.1 – Chassis with printed board
A.2 Maximum printed board dimensions
Figure A.2 illustrates the maximum width and depth of printed board dimensions, depending
on the defined chassis dimensions. See also Tables A.1 and A.2.
Cross-section A-A
Chassis
Printed board
W2
W1
IEC
Figure A.2 – Printed board dimensions
H1
D1
D2
– 12 – IEC 60297-3-109:2015 © IEC 2015
Table A.1 – Printed board width dimensions
Width units W2 max.
n × W
(n × 44,45)
3W
(133,35) 121,44
4W
(177,80) 165,89
5W
(222,25) 210,34
6W
(266,70) 254,79
7W
(311,15) 299,24
8W
(355,60) 343,69
9W
(400,05) 388,14
10W
(444,50) 432,59
Table A.2 – Printed board depth dimensions
D2 max.
Depth units
n × D
(n × 44,45)
3D
(133,35) 121,44
4D
(177,80) 165,89
5D
(222,25) 210,34
6D
(266,70) 254,79
7D
(311,15) 299,24
8D
(355,60) 343,69
9D
(400,05) 388,14
10D
(444,50) 432,59
Annex B
(normative)
Printed board dimensions in conjunction with fan cooling
B.1 Illustrative figure
Figure B.1 illustrates the chassis with a fan unit and printed board.
Chassis
Printed board
Typical fan unit
B B
Air inlet/ air outlet
W1
IEC
Figure B.1 – Chassis with fan cooling
B.2 Maximum printed board dimensions in conjunction with fan cooling
Figure B.2 illustrates an example calculation for the maximum printed board dimensions,
depending on the defined chassis and typical heat dissipation with fans. See also Table B.1.
H1
– 14 – IEC 60297-3-109:2015 © IEC 2015
Dimensions in millimetres
Cross-section B-B
Reserved area for
heat management
with fan cooling
Fan unit
28,0
Fan depth example
54,0 W3 max.
W1
IEC
Figure B.2 – Printed board dimensions in conjunction with fan cooling,
example (fan depth = 28,0 mm)
D1
D2
Table B.1 – Printed board width dimensions
in conjunction with fan cooling, example (fan depth=28,0 mm)
Width units W3 max.
n × W
(n × 44,45)
3W
(133,35) 67,44
4W
(177,80) 111,89
5W
(222,25) 156,34
6W
(266,70) 200,79
7W
(311,15) 245,24
8W
(355,60) 289,69
9W
(400,05) 334,14
10W
(444,50) 378,59
NOTE For stand alone applications, the preferred cooling air flow direction is side to side.

– 16 – IEC 60297-3-109:2015 © IEC 2015
Annex C
(normative)
Chassis mounting options
C.1 Type A: Example for 19” cabinet mounting option
Figure C.1 illustrates a chassis with optional 19” flanges.
D1
W1=443,70 (see Table 2)
W4
W5
Missing dimensions
see IEC 60297-3-100
IEC
Figure C.1 – Type A: Chassis mounting in a 19” cabinet
C.2 Type B: Example for 19” cabinet mounting option
Figure C.2 illustrates two chassis within a subrack type mounting support.
H1
H1
H2
H3
Chassis 1
W1 W1
W4
Missing dimensions
W5
see IEC 60297-3-100
IEC
Figure C.2 – Type B: Chassis mounting in a 19” cabinet
C.3 Type C: Chassis mounting example
Figure C.3 illustrates a chassis with a vertical mounting flange (for example 19 inch
compatible or proprietary).
D1
W1
IEC
Fi
...