IEC 60917-1:2019

IEC 60917-1 ®
Edition 2.0 2019-09
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Modular order for the development of mechanical structures for electrical and
electronic equipment practices –
Part 1: Generic standard
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IEC 60917-1 ®
Edition 2.0 2019-09
REDLINE VERSION
INTERNATIONAL
STANDARD
colour
inside
Modular order for the development of mechanical structures for electrical and

electronic equipment practices –

Part 1: Generic standard
INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
ICS 31.240 ISBN 978-2-8322-7416-3

– 2 – IEC 60917-1:2019 RLV © IEC 2019
CONTENTS
FOREWORD . 4
INTRODUCTION . 6
1 Scope and object . 8
2 Normative references . 8
3 Terms, terminology and definitions . 11
4 Fundamentals and background information . 22
4.1 General . 22
4.2 Structures of electrical and electronic equipment practices . 22
4.3 Dimensional co-ordination with adjacent technical fields . 23
4.4 Preparation of standards for new equipment practices . 25
5 Modular order details . 28
5.1 Modular grid . 28
5.2 Pitches . 28
5.2.1 Base and multiple pitches for equipment practice . 28
5.2.2 Mounting pitches example . 29
5.3 Co-ordination dimensions . 30
5.4 Illustration of the modular order . 31

Figure 1 – Pitch . 12
Figure 2 – Grid. 13
Figure 3 – Rack . 14
Figure 4 – Cabinet . 14
Figure 5 – Case . 15
Figure 6 – Swing frame . 15
Figure 7 – Subrack . 16
Figure 8 – Chassis . 16
Figure 9 – Plug-in unit. 17
Figure 10 – Console. 17
Figure 11 – Plug-in unit guide . 18
Figure 12 – Slides . 18
Figure 13 – Telescopic slides . 19
Figure 14 – Mounting frame . 19
Figure 15 – Mounting plate . 20
Figure 16 – Front panel . 20
Figure 17 – Backplane . 20
Figure 18 – Cabinet panel . 21
Figure 19 – Door . 21
Figure 20 – Mounting section . 22
Figure 21 – Structures levels of electrical and electronic equipment practices. 23
Figure 22 – Structure of equipment practice standards . 27
Figure 23 – Modular grid . 28
Figure 24 – Partitioning of co-ordination dimensions C with the same mounting pitch mp . 30
Figure 25 – Examples of the application of the modular order . 32

Table 1 – Publications containing standardized modular dimensions and/or related
documents . 24
Table 2 – Co-ordination dimensions C . 30
i
– 4 – IEC 60917-1:2019 RLV © IEC 2019
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
MODULAR ORDER FOR THE DEVELOPMENT
OF MECHANICAL STRUCTURES FOR ELECTRICAL
AND ELECTRONIC EQUIPMENT PRACTICES –

Part 1: Generic standard
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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rights. IEC shall not be held responsible for identifying any or all such patent rights.
This redline version of the official IEC Standard allows the user to identify the changes
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International Standard IEC 60917-1 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.
This second edition cancels and replaces the first edition published in 1998 and its Amendment
1:2000. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) added information on newly developed detail specification standards of mechanical
structures for the electrical and electronic equipment practices;
b) added information on newly developed performance test standards for the verifications of
environmental performances and safety aspects and issues of the thermal performance and
thermal management for the electrical and electronic equipment practices;
c) introduced the relations between the mechanical structure for electrical and electronic
system, the verification of environmental performance and safety aspects and issues of the
thermal performance and thermal management for the electrical and electronic equipment
practices.
The text of this standard is based on the following documents:
FDIS Report on voting
48D/703/FDIS 48D/708/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.
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.
A list of all parts in the IEC 60917 series, published under the general title Modular order for
the development of mechanical structures for electrical and electronic equipment practices, can
be found on the IEC website.
The committee has decided that the contents of this publication will remain unchanged until the
stability date indicated on the IEC web site under "http://webstore.iec.ch" in the data related to
the specific publication. At this date, the publication will be
• reconfirmed,
• withdrawn,
• replaced by a revised edition, or
• amended.
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 – IEC 60917-1:2019 RLV © IEC 2019
INTRODUCTION
The trend towards constantly increasing functional integration and ever smaller volume and
space requirements for electronic components and integrated circuits, as well as the advent of
new manufacturing methods, automatic manufacturing and testing equipment and the use of
Computer Aided Engineering (CAE) systems offer users considerable technical and economic
advantages.
In order to ensure that, when using newly developed components, manufacturing methods and
CAE systems, the advantages can be fully exploited during planning, design, manufacture and
testing, it is necessary for equipment practices to meet the following requirements (see IEC
Guide 103):
– arrangement of products with a minimum loss of area and space;
There is a continuous trend towards higher functional integration and smaller electronic
components and integrated circuits. At the same time, new manufacturing methods, automatic
manufacturing and testing equipment, and Computer Aided Engineering (CAE) systems have
created commercial advantages for their users.
For users to take technical and economic advantage of these new components and technologies
during planning, design, manufacturing, and testing, it is necessary for equipment practices to
meet the following requirements (see IEC Guide 103): arrangement of products with a minimum
loss of area and space;
– dimensional interchangeability of products, e.g. regarding overall dimensions, mounting
dimensions (fixing holes, cut-out, etc.);
– dimensional compatibility and determination of interface dimensions of products which:
• are combined with other products, e.g. instruments, racks, panels and cabinets, etc.;
• are used in buildings that have been built in accordance with a modular system, e.g.
column spacing, room height, door height, etc.
An obstacle arises from the use of two systems of dimensioning (inch – metre) that are not
compatible with each other. The use of an interface between both dimensioning systems
represents one way around this obstacle. The recommendation is:
– to use only one dimensioning system and to use SI units.
The dimensions given in 5.3 of this document have been taken from System l of IEC Guide 103
in consideration with other documents on dimensional coordination.
In accordance with the above considerations, IEC 60917-1 Ed.1 was published in 1998. This
generic standard for mechanical structures for electronic equipment practices has been used
to meet advanced requirements for various industrial applications of micro-electronics
technology.
After publication of this generic standard, development of dimensional sectional and detail
specifications consisting of the metric 25 mm modular standards, IEC 60917-2-X, and 19 inch
(in) conventional standards, IEC 60297-3-XXX, was undertaken. In parallel, standards to
address environmental performance and safety aspects of the mechanical structures were
developed as the IEC 61587 series. All these standards are based on indoor system
applications. The next step for the mechanical structure was the developments of the IEC 61969
series for outdoor applications.
In the first decade of the 21st century, the IEC 62194 and IEC 62610 series were developed to
define the verification of the thermal performance of enclosures and address thermal
management issues of the electrical and electronic equipment practices.

This document describes the relationships between the mechanical structure for electrical and
electronic systems, the verification of environmental performance and safety aspects, and the
issues of the thermal performance and of the thermal management for the electrical and
electronic equipment practices.

– 8 – IEC 60917-1:2019 RLV © IEC 2019
MODULAR ORDER FOR THE DEVELOPMENT
OF MECHANICAL STRUCTURES FOR ELECTRICAL
AND ELECTRONIC EQUIPMENT PRACTICES –

Part 1: Generic standard
1 Scope and object
This International Standard relates to equipment practices. The modular order is applicable to
the main structural dimensions of electronic equipment mounted in various installations where
dimensional interfaces have to be considered.
It refers to basic design parameters and is not intended to be used for manufacturing tolerances
or clearances.
In addition, information on interfaces to other technical fields, on technology and advanced
design aspects is included.
This standard also covers standard terms for parts and assemblies of mechanical structures for
electronic equipment.
This generic standard gives the definitions of a modular order for mechanical structures of
electronic equipment and provides for dimensional compatibility at mechanical interfaces with
related engineering applications, e.g. printed boards, components, instrumentation, furniture,
rooms, buildings, etc.
Furthermore, it supports the introduction and application of the modular order rules considering
that:
– compatibility of interface dimensions is aimed at the electronic field on the basis of the SI
unit metre;
– technical and economic advantages can be achieved when using the rules.
The terms in this standard should be used in all standards for mechanical structures of
electronic equipment and in related technical documents.
This part of IEC 60917 specifies the relationships between equipment practices and the modular
order which are applicable to the main structural dimensions of electronic and electrical
equipment mounted in various installations where dimensional interfaces have to be considered
for mechanical compatibility.
This document also established terms for parts and assemblies of mechanical structures for
electrical and electronic equipment, to clarify the specific relations between equipment practices
and modular order.
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 60050-581:1978, International Electrotechnical Vocabulary – Part 581: Electromechanical
components for electronic equipment
IEC 60297 (all parts), Mechanical structures for electronic equipment

IEC 60297-1:1986, Dimensions of mechanical structures of the 482,6 mm (19 in) series – Part 1:
Panels and racks
IEC 60297-2:1982, Dimensions of mechanical structures of the 482,6 mm (19 in) series – Part 2:
Cabinets and pitches of rack structures
IEC 60297-3:1984, Dimensions of mechanical structures of the 482,6 mm (19 in) series – Part 3:
Subracks and associated plug-in units
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 60297-3-101, Mechanical structures for electronic equipment – Dimensions of mechanical
structures of the 482,6 mm (19 in) series – Part 3-101: Subracks and associated plug-in units
IEC 60297-3-102, Mechanical structures for electronic equipment – Dimensions of mechanical
structures of the 482,6 mm (19 in) series – Part 3-102: Injector/extractor handle
IEC 60297-3-103, Mechanical structures for electronic equipment – Dimensions of mechanical
structures of the 482,6 mm (19 in) series – Part 3-103: Keying and alignment pin
IEC 60297-3-104, Mechanical structures for electronic equipment – Dimensions of mechanical
structures of the 482,6 mm (19 in) series – Part 3-104: Connector dependent interface
dimensions of subracks and plug-in units
IEC 60297-3-105, Mechanical structures for electronic equipment – Dimensions of mechanical
structures of the 482,6 mm (19 in) series – Part 3-105: Dimensions and design aspects for 1U
high chassis
IEC 60297-3-106, Mechanical structures for electronic equipment – Dimensions of mechanical
structures of the 482,6 mm (19 in) series – Part 3-106: Adaptation dimensions for subracks and
chassis applicable with metric cabinets or racks in accordance with IEC 60917-2-1
IEC 60297-3-107, Mechanical structures for electronic equipment – Dimensions of mechanical
structures of the 482,6 mm (19 in) series – Part 3-107: Dimensions of subracks and plug-in
units, small form factor
IEC 60297-3-108, Mechanical structures for electronic equipment – Dimensions of mechanical
structures of the 482,6 mm (19 in) series – Part 3-108: Dimensions of R-type subracks and
plug-in units
IEC 60297-3-109, 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 60297-3-110, Mechanical structures for electrical and electronic equipment – Dimensions
of mechanical structures of the 482,6 mm (19 in) series – Part 3-110: Residential racks and
cabinets for smart houses
IEC 60297-4:1995, Dimensions of mechanical structures of the 482,6 mm (19 in) series – Part 4:
Subracks and associated plug-in units – Additional dimensions
IEC 60473:1974, Dimensions for panel-mounted indicating and recording electrical measuring
instruments
– 10 – IEC 60917-1:2019 RLV © IEC 2019
IEC 60629:1978, Standard sheets for a modular system (for installation accessories for use in
domestic and similar installations)
IEC TR 60668:1980, Dimensions of panel areas and cut-outs for panel and rack-mounted
industrial-process measurement and control instruments
IEC 60917-2:1992, Modular order for the development of mechanical structures for electronic
equipment practices – Part 2: Sectional specification – Interface co-ordination dimensions for
the 25 mm equipment practice
IEC 60917-2-1:1993, Modular order for the development of mechanical structures for electronic
equipment practices – 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 practices – 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
IEC 60917-2-3, 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 60917-2-4, Modular order for the development of mechanical structures for electronic
equipment practices – Part 2-4: Sectional specification – Interface co-ordination dimensions for
the 25 mm equipment practice – Adaptation dimensions for subracks or chassis applicable in
cabinets or racks in accordance with IEC 60297-3-100 (19 in)
IEC 60917-2-5, Modular order for the development of mechanical structures for electronic
equipment practices – Part 2-5: Sectional specification – Interface co-ordination dimensions for
the 25 mm equipment practice – Cabinet interface dimensions for miscellaneous equipment
IEC 61554, Panel mounted equipment – Electrical measuring instruments – Dimensions for
panel mounting
IEC 61587 (all parts), Mechanical structures for electronic equipment – Tests for IEC 60917
and IEC 60297 series
IEC 61969-1, Mechanical structures for electronic equipment – Outdoor enclosures – Part 1:
Design guidelines
IEC 61969-2, Mechanical structures for electronic equipment – Outdoor enclosures – Part 2:
Coordination dimensions
IEC 61969-3, Mechanical structures for electronic equipment – Outdoor enclosures – Part 3:
Environmental requirements, tests and safety aspects
IEC 62194, Method of evaluating the thermal performance of enclosures
IEC TS 62454, Mechanical structures for electronic equipment – Design guide: Interface
dimensions and provisions for water cooling of electronic equipment within cabinets of the
IEC 60297 and IEC 60917 series
IEC 62610 (all parts), Mechanical structures for electrical and electronic equipment – Thermal
management for cabinets in accordance with IEC 60297 and IEC 60917 series

IEC Guide 103:1980, Guide on dimensional co-ordination
ISO 31:1992, Quantities and units
ISO 1000:1992, SI units and recommendations for the use of their multiples and of certain other
units
ISO 1006:1983, Building construction – Modular coordination – Basic module
ISO 1040:1983, Building construction – Modular coordination – Multimodules for horizontal
coordinating dimensions
ISO 1791, Building construction – Modular co-ordination – Vocabulary
ISO 2848, Building construction – Modular coordination – Principles and rules
ISO 3827-1:1977, Shipbuilding – Coordination of dimensions in ships' accommodation – Part 1:
Principles of dimensional coordination
ISO 3394, Packaging – Complete, filled transport packages and unit loads – Dimensions of rigid
rectangular packages
ISO 3676, Packaging – Complete, filled transport packages and unit loads – Unit load
dimensions
ISO 6514, Building construction – Modular coordination – Sub-modular increments
ISO 80000-1:2009, Quantities and units – Part 1: General
ISO 80000-3:2006, Quantities and units – Part 3: Space and time
3 Terms, terminology and definitions
For the purposes of this document, the terms and definitions given in IEC 60050-581 as well as
the following 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
3.1
equipment practice
mechanical structure involved in housing and mounting of electrical, electronic and
electromechanical systems
Note 1 to entry: The equipment practice provides for compatibility between mechanical parts, electrical
interconnections and electrical and electronic components.
3.2
modular order
set of rules which establishes a relationship between co-ordination dimensions and the base
pitch, multiple pitches and mounting pitches to be used in equipment practice

– 12 – IEC 60917-1:2019 RLV © IEC 2019
3.3
co-ordination dimension
reference dimension used to co-ordinate mechanical interfaces. This is not a manufacturing
dimension with a tolerance.
NOTE – An actual outside dimension of a mechanical structure related to a co-ordination dimension can only
decrease.
3.4
aperture dimension
special co-ordination dimension for the usable space between features (structural parts)
Note 1 to entry: The actual inside dimension of an aperture can only increase.
3.5
n
multiplier having integer values of range continuing in continuous series of integers 1, 2, 3, .
3.6
pitch
one division step of a regularly subdivided coordinate
SEE: Figure 1.
Figure 1 – Pitch
3.7
base pitch
p
smallest distance between adjacent grid lines used in the equipment practices
3.8
multiple pitch
Mp
integer multiple of the base pitch
3.9
mounting pitch
mp
pitch used to arrange parts or assemblies in a given space
Note 1 to entry: The nominal value of a mounting pitch is achieved by using a base or multiple pitch multiplied by
a factor F from Table 2.
Note 2 to entry: Actual dimensions used in an equipment practice are created for the nominal mounting pitch and
they include manufacturing tolerance.
3.10
reference plane
theoretical plane without thickness or tolerances used to define spaces

3.11
grid
two- or three-dimensional arrangement of pitches used to coordinate a position, complying with
the modular order
SEE: Figure 2.
Figure 2 – Grid
3.12
module
three-dimensional structure where all sides are multiples of whole numbers of the pitch, it could
can also be used in a two-dimensional grid.
Note 1 to entry: One dimensional module is often called unit (U) in some documents.
3.13
suite of racks
suite of cabinets
row of racks or cabinets placed side by side

– 14 – IEC 60917-1:2019 RLV © IEC 2019
3.14
rack
free-standing or fixed structure for housing electronic or electrical equipment
SEE: Figure 3.
Example 1 Example 2 Example 3
Figure 3 – Rack
3.15
cabinet
free-standing and self-supporting enclosure for housing electronic and/or electrical equipment.
It is usually fitted with doors and/or side panels which may or may not be removable
SEE: Figure 4.
Figure 4 – Cabinet
3.16
case
table, bench or wall mounted enclosure in which electronic and /or electrical equipment can be
housed
SEE: Figure 5.
Figure 5 – Case
3.17
swing frame
hinged frame for housing electronic and/or electrical equipment
The frame swings to permit access to the reverse side.
Note 1 to entry: The hinge frame swings to permit access to the back.
SEE: Figure 6.
Figure 6 – Swing frame
– 16 – IEC 60917-1:2019 RLV © IEC 2019
3.18
subrack
structural unit for housing printed boards with components inserted, and plug-in units
SEE: Figure 7.
Figure 7 – Subrack
3.19
chassis
mechanical structure designed specifically to support associated electrical and electronic
components
SEE: Figure 8.
Figure 8 – Chassis
3.20
plug-in unit
unit which plugs into a subrack and is supported by guides
Note 1 to entry: These units can be of various types, ranging from a printed board with components inserted to a
frame or box-type unit designed with a plug-in connection.
SEE: Figure 9.
Figure 9 – Plug-in unit
3.21
console
table-mounted or floor-standing enclosure having horizontal, vertical and/or sloping faces to
accommodate control, information and monitoring equipment
SEE: Figure 10.
Figure 10 – Console
– 18 – IEC 60917-1:2019 RLV © IEC 2019
3.22
plug-in unit guide
device to guide, locate and support plug-in units and printed boards, with components inserted,
in subracks
SEE: Figure 11.
Figure 11 – Plug-in unit guide

3.23
slides
angle-bars on which subracks and chassis may slide and be supported within a rack, cabinet
or case
SEE: Figure 12.
Figure 12 – Slides
3.24
telescopic slides
devices to support withdrawable subracks and chassis in the extended position
SEE: Figure 13.
Figure 13 – Telescopic slides
3.25
mounting frame
frame design of profiles for the mounting of electronic /electrical devices. Fixed or movable
location within cabinets
SEE: Figure 14.
Figure 14 – Mounting frame
3.26
mounting plate
plate for the mounting of electronic/electrical devices, located within e.g. cabinets

– 20 – IEC 60917-1:2019 RLV © IEC 2019
SEE: Figure 15.
Figure 15 – Mounting plate
3.27
front panel
plane panel allocated to the vertical mounting area of racks and cabinets
SEE: Figure 16.
Figure 16 – Front panel
3.28
backplane
mounting plane of connectors and printed board for the electrical interconnection of plug-in
units within a subrack or chassis
SEE: Figure 17.
Figure 17 – Backplane
3.29
cabinet panel
design part of a cabinet as protection against incidental touch and environmental influences
SEE: Figure 18.
Figure 18 – Cabinet panel
3.30
door
hinged cabinet panel, typically incorporating latching and/or locking devices
SEE: Figure 19.
Figure 19 – Door
– 22 – IEC 60917-1:2019 RLV © IEC 2019
3.31
mounting section
compartment of a cabinet for the assembly of interior parts
SEE: Figure 20.
Figure 20 – Mounting section
4 Fundamentals and background information
4.1 General
The basis of the modular order is the basic Sl unit of length, the metre according to
ISO 1000 and to ISO 31-1 ISO 80000-1 and to lSO 80000-3.
For compatibility with other modular orders, see IEC 60473, IEC 60629 and IEC 60668 and
ISO 1006, ISO 1040 and ISO 3827-1 lEC 61554, IEC TR 60668, lSO 1006 and ISO 1040.
4.2 Structures of electrical and electronic equipment practices
ln Figure 21, the four structure levels of presently known electronic equipment practices are
outlined.
It should be understood that The modular order not only covers this kind of structure, but also
any other structure of new electrical and electronic equipment practice designs where a modular
grid with metric pitches and co-ordination dimensions can be allocated.

Figure 21 – Structures levels of electrical and electronic equipment practices
4.3 Dimensional co-ordination with adjacent technical fields
Developing a new electrical and/or electronic equipment practice requires the consideration of
external and internal interfaces.
The most important interfaces to electronic and electrical equipment practice are:
a) External interfaces
– buildings with their room facilities, for example doors, elevators, tiles on floor and ceiling,
etc.;
– packaging and transport, for example, pallets and containers for lorries, ships and
aircraft;
– joint installation of various equipment, for example switching and transmission, power
supply, industrial process equipment, etc.
b) Internal interfaces
– printed circuits, connectors, electromechanical components, electrical components;
– semiconductor components;
– wiring and cables;
– functional units such as a.c./d.c. convertor, measure and control instruments, fuses, etc.
Many of these interfaces have to be considered when specifying the requirements of any
equipment practice for electronic and /or electrical systems. For such interfaces co-ordination
dimensions should be used as means to reach dimensional compatibility with adjacent technical
fields.
Table 1 gives an overview of ISO and lEC publications that should be considered when relevant
co-ordination dimensions for common interfaces have to be determined.

– 24 – IEC 60917-1:2019 RLV © IEC 2019
Table 1 – Publications containing standardized modular
dimensions and/or related documents
Co-ordination
Publication Title dimensions
mm
ISO 2848 Building construction – Modular co-ordination – Principles and rules ----
(1984)
ISO 1791 Building construction – Modular co-ordination – Vocabulary (1983) -----

ISO 1006 Building construction – Modular co-ordination – Basic module (1983) 100
ISO 6514 Building construction – Modular co-ordination – Sub-modular 20; 25; 50
increments (1982)
ISO 1040 Building construction – Modular co-ordination – Multimodules for 300; 600; 1 200;
horizontal co-ordinating dimensions (1983) 1 500; 3 000; 6 000
ISO 3394 Dimensions for rigid rectangular packages – Transport packages
600 × 400 .
(1984)
1 200 × 800 .
ISO 3676 Packaging – Unit load sizes – Dimensions (1983) 1 200 × 800 .
ISO 3827-1 Shipbuilding – Co-ordination of dimensions in ships' accommodation – 50; 100; 300
Part 1: Principles of dimensional co-ordination (1977)
IEC Guide 103 Guide on dimensional co-ordination (1980) 0,5; 1; 2,5
(system I)
IEC 60097 Grid systems for printed circuits (1991) 0,05; 0,5
IEC 60255-18 Electrical relays – Part 18: Dimensions for general purpose 2,5 and 5
all-or-nothing relays (1982)
IEC 60629 Standard sheets for a modular system (for installation accessories 12,5
for use in domestic and similar installations) (1978)
IEC 60473 Dimensions for panel-mounted indicating and recording electrical 12,5
measuring instruments (1974)
IEC 60668 Dimensions of panel areas and cut-outs for panel and rack-mounted 12,5
industrial-process measurement and control instruments (1980)
IEC 60297-2 Dimensions of mechanical structures of the 482,6 mm (19 in) series – 100
Part 2: Cabinets and pitches of rack structures (1982)

Publication Title Co-ordination
dimensions
mm
ISO 2848 Building construction – Modular coordination – Principles and rules ---
ISO 1791 Building construction – Modular co-ordination – Vocabulary ---
ISO 1006 Building construction – Modular coordination – Basic module 100
ISO 6514 Building construction – Modular coordination – Sub-modular 20; 25; 50
increments
ISO 1040 Building construction – Modular coordination – Multimodules for 300; 600; 1 200;
horizontal coordinating dimensions 1 500; 3 000; 6 000
ISO 3394 Packaging – Complete, filled transport packages and unit loads – 600 x 400
Dimensions of rigid rectangular packages 1 200 x 800
ISO 3676 Packaging – Complete, filled transport packages and unit loads – Unit 1 200 x 800
load dimensions
IEC GUIDE 103 Guide on dimensional co-ordination 0,5; 1; 2,5
(system I)
IEC TR 60668 Dimensions of panel areas and cut-outs for panel and rack-mounted 12,5
industrial-process measurement and control instruments

IEC 60297-3-100 Dimensions of mechanical structures of the 482,6 mm (19 in) series – 100
Part 3-100: Basic dimensions of front panels, subracks, chassis, racks
and cabinets
IEC 61969-2 Mechanical structures for electronic equipment – Outdoor enclosures – 25
Part 2: Coordination dimensions

4.4 Preparation of standards for new equipment practices
IEC standards for equipment practices to be prepared in accordance with this standard should
shall be based on the following structure (See Figure 22).
a) Generic standard
All new equipment practices should shall comply with this document.
b) Sectional specification standards
They describe particular equipment practices within the scope of the generic standard. In a
sectional standard, co-ordination dimensions (selected from the generic standard) shall be
specified as standard dimensions, for example for height, width, depth, and so on. There may
be more than one sectional standard based on different multiple pitches.
c) Detail specification standards
They standardize units or subunits of equipment practice described in a sectional standard.
These units could be such as cabinets, racks, subracks, chassis, backplanes, front panels and
plug-in units, etc., and the details can be dimensions, tolerances, requirements, etc., under the
condition that mechanical compatibility is maintained.
NOTE Related with the mechanical structure for equipment practices, Figure 22 contains categorised standards
and technical specifications.
a) Conventional standard (Legacy system): IEC 60297 series, Dimensions of mechanical structures of the 482,6
mm (19 in) series, defines the detail dimensions of the structure levels through the level 1 to the level 4 as the
same as the structure levels shown in Figure 21, and the level 4 of IEC 60297 series can be adaptable to the 25
mm co-ordination dimensions of IEC 60917-2. Standards in the IEC 60297 series are treated as detail
specification standards in Figure 22.
b) Outdoor enclosures: IEC 61969 series defines dimensions, environmental requirements of the protective outer-
shells for outdoor applications (stationary uses at non-weather protected locations) of the mechanical structures
in accordance with IEC 60917 series and IEC 60297 series and other equipment practices.
c) Performance test standards: IEC 61587 series, IEC 62610 series and IEC TS 62454 provide specifications and
requirements for verifications of environmental issues and thermal managements related with equipment
practices applying mechanical structures in accordance with IEC 60917 series and IEC 60297 series. IEC 62194
specifies the test method for thermal performance of outdoor enclosures.

– 26 – IEC 60917-1:2019 RLV © IEC 2019

IEC 60917-1
Generic standard
Modular order for
the development of
mechani
...