IEC 61231:2010

IEC 61231 ®
Edition 1.0 2010-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
International lamp coding system (ILCOS)

Système international de codification des lampes (ILCOS)

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IEC 61231 ®
Edition 1.0 2010-01
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
International lamp coding system (ILCOS)

Système international de codification des lampes (ILCOS)

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
PRICE CODE
INTERNATIONALE
T
CODE PRIX
ICS 29.140 ISBN 978-2-88910-449-9
– 2 – 61231 © IEC:2010
CONTENTS
FOREWORD.3
INTRODUCTION.5
1 Scope and object .6
2 Normative references.6
3 Principles .6
4 Basic structure.7
4.1 Letter section.7
4.2 Figure section.7
4.3 Length of the code.8
5 Lamp categories .9
5.1 Tungsten filament lamps.9
5.2 Tungsten halogen lamps (non-vehicle).12
5.3 Fluorescent lamps .13
5.4 High-pressure sodium vapour lamps .17
5.5 Low-pressure sodium vapour lamps .18
5.6 High-pressure mercury vapour lamps.19
5.7 Metal halide lamps.19
5.8 LED modules.21
5.9 Special lamps .22
Annex A (informative) Survey ILCOS L – short version, letter section.23
Bibliography .24

Table 1 – Dimensions.15

61231 © IEC:2010 – 3 –
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
INTERNATIONAL LAMP CODING SYSTEM (ILCOS)

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
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8) Attention is drawn to the Normative references cited in this publication. Use of the referenced publications is
indispensable for the correct application of this publication.
9) Attention is drawn to the possibility that some of the elements of this IEC Publication may be the subject of
patent rights. IEC shall not be held responsible for identifying any or all such patent rights.
International Standard IEC 61231 has been prepared by subcommittee 34A: Lamps, of IEC
technical committee 34: Lamps and related equipment.
This first edition cancels and replaces the second edition of IEC 61231, published as a
technical specification. It constitutes a technical revision, of which the main changes are
indicated below:
– introduction of LED modules (Subclause 5.8).
The text of this standard is based on the following documents:
CDV Report on voting
34A/1345/CDV 34A/1374/RVC
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.

– 4 – 61231 © IEC:2010
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.
61231 © IEC:2010 – 5 –
INTRODUCTION
The lamp industry strives continuously to meet customers' needs. Its innovative power has led
to a tremendous variety of different light sources. To enable customers and experts to find their
way within the diversity of products, a general system for the coding of lamps has been
developed.
The code does not replace specific markings used by individual manufacturers on their lamps
or in their catalogues, but it is promoted for cross-referencing purposes and, in due course, to
replace national and regional lamp coding systems which already exist.
NOTE The code does not give all the technical characteristics necessary to specify a lamp fully. For this the
relevant lamp standard and/or the manufacturer’s literature have to be consulted.

– 6 – 61231 © IEC:2010
INTERNATIONAL LAMP CODING SYSTEM (ILCOS)

1 Scope and object
This International Standard gives the rules for the international lamp coding system and covers
all lamp categories, excluding vehicle lamps. Coding for the main lamp types is specified and,
for the others, will follow by amendments to this standard as appropriate.
The object of the international lamp coding system is
– to improve communication about the different types of lamps;
– to help in discussions concerning interchangeability and compatibility of products;
– to create a closer relationship between international standards and manufacturers’ literature
(for example the code could be given in future in the relevant parts of a standard);
– to enable correct replacements of lamps;
– to be used as a complementary marking on the luminaire;
– to replace national and regional coding systems.
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 60357, Tungsten halogen lamps (non-vehicle) – Performance specifications
IEC 60432-1, Incandescent lamps – Safety specifications – Part 1: Tungsten filament lamps for
domestic and similar general lighting purposes
IEC 60432-2, Incandescent lamps – Safety spe
...