EN IEC 60238:2018

Edison screw lampholders

IEC 60238:2016 is available as IEC 60238:2016 RLV which contains the International Standard and its Redline version, showing all changes of the technical content compared to the previous edition. IEC 60238:2016 applies to lampholders with Edison thread E14, E27 and E40, designed for connection to the supply of lamps and semi-luminaires only. It also applies to switched-lampholders for use in AC circuits only, where the working voltage does not exceed 250 V r.m.s. This ninth edition cancels and replaces the eighth edition published in 2004, Amendment 1: 2008 and Amendment 2:2011. This edition constitutes a technical revision. This edition includes the following significant technical changes with respect to the previous edition: a) Addition of a pull test for certain E5 and E10 lampholders. b) Annex D listing amended requirements/clauses which require products to be retested.

Lampenfassungen mit Edisongewinde

Douilles à vis Edison pour lampes

L'IEC 60238:2016 s'applique aux douilles à vis Edison E14, E27 et E40 destinées uniquement au raccordement des lampes et des semi-luminaires à l'alimentation. Elle s'applique aussi aux douilles à interrupteur destinées exclusivement aux circuits de courant alternatif dont la tension de travail ne dépasse pas 250 V (valeur efficace). Cette neuvième édition annule et remplace la huitième édition parue en 2004, l'Amendement 1: 2008 et l'Amendement 2:2011. Cette édition constitue une révision technique. Cette édition inclut les modifications techniques majeures suivantes par rapport à l'édition précédente: a) Addition d'un essai de traction pour certaines douilles E5 et E10. b) Une Annexe D répertoriant les exigences/articles amendés nécessitant la réalisation de nouveaux essais sur les produits.

Okovi za žarnice in sijalke z Edisonovim navojem (IEC 60238:2016)

Ta mednarodni standard velja za okove za žarnice in sijalke z Edisonovim navojem E14, E27 in E40, ki so zasnovani samo za povezavo sijalk in polsijalk1 z napajanjem.
Uporablja se tudi za okove za žarnice in sijalke s stikali za uporabo samo v izmeničnih tokokrogih, kjer delovna napetost ne presega 250 V RMS.
Ta standard velja tudi za okove za žarnice in sijalke z Edisonovim navojem E5, ki so zasnovani za povezavo serije povezanih sijalk z napajalnim omrežjem z delovno napetostjo do 25 V in za uporabo v notranjih prostorih, ter za okove za žarnice in sijalke z Edisonovim navojem E10, ki so zasnovani za povezavo serije povezanih sijalk z napajalnim omrežjem z delovno napetostjo do 60 V ter za uporabo v notranjih in zunanjih prostorih. Uporablja se tudi za okove E10 za vgradnjo, za povezavo posamezne sijalke z napajanjem. Ti okovi za žarnice in sijalke niso namenjeni prodaji na drobno.
Kolikor je smiselno ta standard zajema tudi druge okove za žarnice in sijalke, ki nimajo Edisonovega navoja in so zasnovane za povezavo serije povezanih sijalk z napajanjem.
OPOMBA: Takšni okovi se na primer uporabljajo pri svetlobnih nizih za osvetlitev novoletnih jelk. Kolikor je smiselno ta standard zajema tudi adapterje.
Ta standard zajema tudi okove, ki so, deloma ali v celoti, del sijalk ali bodo vgrajeni v naprave. Zajema samo zahteve za okove za sijalke in žarnice. Za vse druge zahteve, kot je zaščita pred električnim udarom v območju terminalov in vznožkov, se upoštevajo zahteve zadevnega standarda za naprave, ki se preskusijo po vgradnji v ustrezno opremo, ta oprema pa je preskušena po lastnem standardu. Takšni okovi ter tudi okovi, ki imajo zaskočno zunanjo lupino, ki jih uporabljajo samo proizvajalci sijalk, niso namenjeni prodaji na drobno.
Ta standard velja za okove, ki se uporabljajo v notranjih ali zunanjih prostorih za svetlobne naprave v stanovanjskih in industrijskih objektih. Uporablja se tudi za okove v obliki sveč. Na območjih, kjer prevladujejo posebne razmere, npr. pri cestni razsvetljavi, na ladjah, v vozilih ter v nevarnih območjih, npr. kjer so možne eksplozije, so morda potrebne posebne konstrukcije.
Ta standard se ne uporablja za okove E26d za lučke za okrasitev novoletne jelke.
Ta standard temelji na naslednjih podatkih v zvezi s sijalkami za splošno razsvetljavo:
– vznožki E14 se uporabljajo za sijalke s tokom do 2 A;
– vznožki E27 se uporabljajo za sijalke s tokom do 4 A;
– vznožki E40 se uporabljajo za sijalke s tokom do 16 A oziroma 32 A, če nazivna napetost napajanja ne presega 130 V (glej 5.5 in 6.3).
Če so v svetilkah uporabljeni okovi, so njihove najvišje temperature delovanja določene v IEC 60598.

General Information

• Status: Published
• Publication Date: 22-Mar-2018
• Withdrawal Date: 22-Mar-2021
• ICS: 29.140.10 - Lamp caps and holders
• Technical Committee: CLC/TC 34 - 'Lamps and related equipment
• Drafting Committee: IEC/SC 34B - IEC_SC_34B
• Current Stage: 6060 - Document made available - Publishing
• Start Date: 23-Mar-2018
• Completion Date: 23-Mar-2018
• Directive: 2014/35/EU - Directive 2014/35/EU of the European Parliament and of the Council of 26 February 2014 on the harmonisation of the laws of the Member States relating to the making available on the market of electrical equipment designed for use within certain voltage limits
• Mandate: M/511 - Mandate to CEN, CENELEC and ETSI relating to harmonised standards in the field of the Low Voltage Directive
• Ref Project: SIST EN IEC 60238:2018 - Edison screw lampholders (IEC 60238:2016)

Relations

• Replaces: EN 60238:2004 - Edison screw lampholders
• Effective Date: 28-Jan-2023
• Replaces: EN 60238:2004/A2:2011 - Edison screw lampholders
• Effective Date: 28-Jan-2023
• Replaces: EN 60238:2004/A1:2008 - Edison screw lampholders
• Effective Date: 28-Jan-2023
• Amended By: EN IEC 60238:2018/A1:2018 - Edison screw lampholders
• Effective Date: 23-Jan-2023
• Amended By: EN IEC 60238:2018/A11:2021 - Edison screw lampholders
• Effective Date: 07-Dec-2021
• Amended By: EN IEC 60238:2018/A2:2021 - Edison screw lampholders
• Effective Date: 03-Apr-2018

Overview

EN IEC 60238:2018 (adoption of IEC 60238:2016) specifies safety, construction and test requirements for Edison screw lampholders. It applies to lampholders with thread sizes E14, E27 and E40, and to switched lampholders intended for AC circuits with a working voltage up to 250 V r.m.s.. Edition 9.0 is a technical revision that supersedes the 2004 edition and its amendments; an RLV (Redline Version) is available showing changes from the previous edition.

Key updates in this edition include the addition of a pull test for certain E5 and E10 lampholders and an Annex D that lists amended requirements/clauses that require product retesting.

Key topics and requirements

The standard addresses the full lifecycle of lampholder design, testing and marking, including:

• Scope and classifications for Edison screw lampholders (E14, E27, E40)
• Marking and identification requirements tied to safe use and traceability
• Dimensions and interchangeability (gauges and thread details)
• Protection against electric shock, creepage distances and clearances
• Terminals, earthing provisions and connections
• Mechanical strength tests (impact, tumbling, normal operation)
• Electrical tests (insulation resistance, dielectric strength)
• Resistance to heat, fire and tracking (glow-wire and needle-flame tests referenced)
• Season cracking / corrosion tests (Annex A) and other durability checks
• Requirements for switched lampholders and guidance relating to IEC 61058-1
• Annex D: schedule of amended subclauses that may trigger retesting
• Normative references to related standards (IEC 60061, IEC 60598-1, IEC 60695 series, etc.)

Practical applications

EN IEC 60238:2018 is used to ensure that Edison screw lampholders are safe, reliable and compatible with lamps and semi-luminaires. Typical practical uses:

• Product design and specification of lampholders (E14/E27/E40)
• Type testing and certification for CE marking under the EU Low Voltage Directive
• Quality control and production testing (mechanical and electrical endurance)
• Supplier and procurement verification for lighting components
• Retesting when design clauses in Annex D are amended

Who should use this standard

• Lamp and lampholder manufacturers and component designers
• Luminaire and appliance manufacturers integrating lampholders
• Test laboratories and conformity assessment bodies
• Compliance engineers, product safety officers and procurement teams
• National standards bodies and regulatory authorities (CENELEC adoption)

Related standards

EN IEC 60238 references and aligns with other electrotechnical standards such as IEC/EN 60061 (lamp caps and gauges), IEC 60598-1 (luminaires), IEC 60695 (fire testing) and IEC 61058-1 (switches), which are relevant for complete product compliance and testing strategies.

Keywords: EN IEC 60238:2018, Edison screw lampholders, E14, E27, E40, lampholder standard, lampholders testing, IEC 60238:2016, Low Voltage Directive, lamp caps and holders.

Standards Content (Sample)

SLOVENSKI STANDARD
01-julij-2018
1DGRPHãþD
SIST EN 60238:2005
SIST EN 60238:2005/A1:2008
SIST EN 60238:2005/A2:2011
Okovi za žarnice in sijalke z Edisonovim navojem (IEC 60238:2016)
Edison screw lampholders (IEC 60238:2016)
Ta slovenski standard je istoveten z: EN IEC 60238:2018
ICS:
29.140.10 Grla in držala žarnic Lamp caps and holders
2003-01.Slovenski inštitut za standardizacijo. Razmnoževanje celote ali delov tega standarda ni dovoljeno.

EUROPEAN STANDARD EN IEC 60238

NORME EUROPÉENNE
EUROPÄISCHE NORM
March 2018
ICS 29.140.10 Supersedes EN 60238:2004
English Version
Edison screw lampholders
(IEC 60238:2016)
Douilles à vis Edison pour lampes Lampenfassungen mit Edisongewinde
(IEC 60238:2016) (IEC 60238:2016)
This European Standard was approved by CENELEC on 2016-08-18. CENELEC members are bound to comply with the CEN/CENELEC
Internal Regulations which stipulate the conditions for giving this European Standard the status of a national standard without any alteration.
Up-to-date lists and bibliographical references concerning such national standards may be obtained on application to the CEN-CENELEC
Management Centre or to any CENELEC member.
This European Standard exists in three official versions (English, French, German). A version in any other language made by translation
under the responsibility of a CENELEC member into its own language and notified to the CEN-CENELEC Management Centre has the
same status as the official versions.
CENELEC members are the national electrotechnical committees of Austria, Belgium, Bulgaria, Croatia, Cyprus, the Czech Republic,
Denmark, Estonia, Finland, Former Yugoslav Republic of Macedonia, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Latvia,
Lithuania, Luxembourg, Malta, the Netherlands, Norway, Poland, Portugal, Romania, Serbia, Slovakia, Slovenia, Spain, Sweden,
Switzerland, Turkey and the United Kingdom.

European Committee for Electrotechnical Standardization
Comité Européen de Normalisation Electrotechnique
Europäisches Komitee für Elektrotechnische Normung
CEN-CENELEC Management Centre: Rue de la Science 23, B-1040 Brussels
© 2018 CENELEC All rights of exploitation in any form and by any means reserved worldwide for CENELEC Members.
Ref. No. EN IEC 60238:2018 E
European foreword
The text of document 34B/1852/FDIS, future edition 9 of IEC 60238, prepared by SC 34B "Lamp caps
and holders" of IEC/TC 34 "Lamps and related equipment" was submitted to the IEC-CENELEC
parallel vote and approved by CENELEC as EN IEC 60238:2018.
The following dates are fixed:
2018-09-23
• latest date by which the document has to be implemented at
national level by publication of an identical national
standard or by endorsement
2021-03-23
• latest date by which the national standards conflicting with
the document have to be withdrawn
This document supersedes EN 60238:2004.
Attention is drawn to the possibility that some of the elements of this document may be the subject of
patent rights. CENELEC [and/or CEN] shall not be held responsible for identifying any or all such
patent rights.
This document has been prepared under a mandate given to CENELEC by the European Commission
and the European Free Trade Association, and supports essential requirements of EU Directive(s).
For the relationship with EU Directive(s) see informative Annex ZZ, which is an integral part of this
document.
Endorsement notice
The text of the International Standard IEC 60238:2016 was approved by CENELEC as a European
Standard without any modification.
In the official version, for Bibliography, the following notes have to be added for the standards indicated:
IEC 60061 NOTE Harmonized in EN 60061 series.
IEC 60061-4 NOTE Harmonized as EN 60061-4.
IEC 60068-2-20 NOTE Harmonized as EN 60068-2-20.
IEC 60335-1:2001 NOTE Harmonized as EN 60335-1:2002 (modified).
IEC 60335-2-24:2002 NOTE Harmonized as EN 60335-2-24:2003 (not modified).
IEC 60598 NOTE Harmonized in EN 60598 series.
IEC 60664-1 NOTE Harmonized as EN 60664-1.
IEC 60695-2-10 NOTE Harmonized as EN 60695-2-10.
Annex ZA
(normative)
Normative references to international publications
with their corresponding European publications
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.
NOTE 1 When an International Publication has been modified by common modifications, indicated by (mod),
the relevant EN/HD applies.
NOTE 2 Up-to-date information on the latest versions of the European Standards listed in this annex is
available here: www.cenelec.eu.
Publication Year Title EN/HD Year
IEC 60061-1 (mod) 1969 Lamp caps and holders together with EN 60061-1 1993
gauges for the control of interchangeability
and safety -- Part 1: Lamp caps
IEC 60061-2 (mod) 1969 Lamp caps and holders together with EN 60061-2 1993
gauges for the control of interchangeability
and safety -- Part 2: Lampholders
IEC 60061-3 (mod) 1969 Lamp caps and holders together with EN 60061-3 1993
gauges for the control of interchangeability
and safety -- Part 3: Gauges
IEC 60068-2-32 1975 Basic environmental testing procedures - - -
Part 2: Tests - Test Ed: Free fall
IEC 60068-2-75 2014 Environmental testing - Part 2-75: Tests - EN 60068-2-75 2014
Test Eh: Hammer tests
IEC 60112 2003 Method for the determination of the proof EN 60112 2003
and the comparative tracking indices of
solid insulating materials
+ A1 2009  + A1 2009
IEC 60227 series Polyvinyl chloride insulated cables of rated - -
voltages up to and including 450/750 V --
Part 1: General requirements
IEC 60245 series Rubber insulated cables - Rated voltages - -
up to and including 450/750 V -- Part 1:
General requirements
IEC 60352-1 1997 Solderless connections -- Part 1: Wrapped EN 60352-1 1997
connections - General requirements, test
methods and practical guidance
IEC 60399 2004 Barrel thread for lampholders with shade EN 60399 2004
+ A1 2008 holder ring + A1 2008
IEC 60417 2002 Graphical symbols for use on equipment - -
IEC 60529 1989 Degrees of protection provided by EN 60529 1991
enclosures (IP Code)
- -  + corrigendum May 1993
+ A1 1999  + A1 2000
+ A2 2013  + A2 2013
IEC 60598-1 (mod) 2014 Luminaires -- Part 1: General requirements EN 60598-1 2015
and tests
IEC 60630 (mod)1994  Maximum lamp outlines for incandescent EN 60630 1998
+ A7 2014 lamps + A7 2015
IEC 60695-2-11 2014 Fire hazard testing - Part 2-11: EN 60695-2-11 2014
Glowing/hot-wire based test methods -
Glow-wire flammability test method for
end-products (GWEPT)
IEC 60695-11-5 2016 Fire hazard testing -- Part 11-5: Test EN 60695-11-5 2017
flames - Needle-flame test method -
Apparatus, confirmatory test arrangement
and guidance
IEC 61058-1 (mod) 2000 Switches for appliances -- Part 1: General EN 61058-1 1)
requirements
ISO 4046-4 2002 Paper, board, pulps and related terms - - -
Vocabulary -- Part 4: Paper and board
grades and converted products
1) EN 61058-1:2002 consists of IEC 61058-1:2000 (modified) and IEC 61058-1:2000/A1:2001 (not modified).
Annex ZZ
(informative)
Relationship between this European standard and the safety objectives of
Directive 2014/35/EU [2014 OJ L96] aimed to be covered
This European standard has been prepared under a Commission’s standardisation request relating to
harmonised standards in the field of the Low Voltage Directive, M/511, to provide one voluntary means
of conforming to safety objectives of Directive 2014/35/EU of the European Parliament and of the
Council of 26 February 2014 on the harmonisation of the laws of the Member States relating to the
making available on the market of electrical equipment designed for use within certain voltage limits
[2014 OJ L96].
Once this standard is cited in the Official Journal of the European Union under that Directive,
compliance with the normative clauses of this standard given in Table ZZ.1 confers, within the limits of
the scope of this standard, a presumption of conformity with the corresponding safety objectives of
that Directive, and associated EFTA regulations.

Table ZZ.1 – Correspondence between this European standard and Annex I of Directive
2014/35/EU [2014 OJ L96]
Safety objectives of Directive Clause(s) / sub-clause(s)
Remarks / Notes
2014/35/EU of this EN
1. General conditions
a) the essential characteristics, Clause 8
the recognition and observance

of which will ensure that
electrical equipment will be used
safely and in applications for

which it was made, shall be
marked on the electrical
equipment, or, if this is not
possible, on an accompanying
document;
b) the electrical equipment, All clauses
together with its component
parts, shall be made in such a

way as to ensure that it can be
safely and properly assembled
and connected;
c) the electrical equipment shall See item 2 and 3 of this table
be so designed and
manufactured as to ensure that
protection against the hazards
set out in points 2 and 3 is
assured, providing that the
equipment is used in
applications for which it was
made and is adequately
maintained.
2. Protection against hazards
arising from the electrical
equipment
Measures of a technical nature
shall be laid down in accordance
with point 1, in order to ensure
that:
a) persons and domestic Clauses 4, 9, 10, 11, 12, 13, 14,
15 and 17
animals are adequately
protected against the danger of

physical injury or other harm
which might be caused by direct
or indirect contact;
b) temperatures, arcs or Clauses 13, 15, 18, 19, 20 and
radiation which would cause a
danger, are not produced;
c) persons, domestic animals Clauses 4, 13, 16, 19 and 22
and property are adequately
protected against non-electrical

dangers caused by the electrical
equipment which are revealed
by experience;
d) the insulation is suitable for Clauses 10, 12, 13, 16, 18, 20

foreseeable conditions. and 21
3. Protection against hazards
which may be caused by
external influences on the
electrical equipment
Technical measures shall be
laid down in accordance with
point 1, in order to ensure that
the electrical equipment:
a) meets the expected Clauses 8, 9, 13, 16 and 22
mechanical requirements in
such a way that persons,
domestic animals and property
are not endangered;
b) is resistant to non-mechanical Clauses 13, 15,18, 20 and 21
influences in expected
environmental conditions, in
such a way that persons,
domestic animals and property
are not endangered;
c) does not endanger persons, Clauses 13, 15, 20 and 21
domestic animals and property
in foreseeable conditions of
overload.
WARNING 1: Presumption of conformity stays valid only as long as a reference to this European
standard is maintained in the list published in the Official Journal of the European Union. Users of this
standard should consult frequently the latest list published in the Official Journal of the European
Union.
WARNING 2: Other Union legislation may be applicable to the product(s) falling within the scope of
this standard.
IEC 60238 ®
Edition 9.0 2016-07
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
Edison screw lampholders
Douilles à vis edison pour lampes

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE
ICS 29.140.10 ISBN 978-2-8322-3465-5

– 2 – IEC 60238:2016 © IEC 2016
CONTENTS
FOREWORD .4
1 Scope .6
2 Normative references .7
3 Terms and definitions .8
4 General requirement . 11
5 General conditions for tests . 11
6 Standard ratings . 12
7 Classification . 13
8 Marking . 14
9 Dimensions . 17
10 Protection against electric shock. 19
11 Terminals . 22
12 Provision for earthing . 25
13 Construction . 26
14 Switched lampholders . 31
15 Moisture resistance, insulation resistance and electric strength . 32
16 Mechanical strength . 35
17 Screws, current-carrying parts and connections . 39
18 Creepage distances and clearances . 41
19 Normal operation . 44
20 General resistance to heat . 45
21 Resistance to heat, fire and tracking . 47
22 Resistance to excessive residual stresses (season cracking) and to rusting . 50
Annex A (normative) Season cracking/corrosion test . 71
Annex B (informative) Guidance for requirements in IEC 61058-1 applicable to
switches in lampholders (see 14.2) . 73
Annex C (informative) Guidance for special requirements in appliance standards –
Household and similar electrical appliances . 75
Annex D (informative) Schedule of amended subclauses containing more
serious/critical requirements which require products to be retested . 77
Bibliography . 78

Figure 1a –Nipple thread for lampholders: metric thread. Basic profile and design
profile for the nut and for the screw . 51
Figure 1b –Nipple thread for lampholders: ISO standard pipe thread. Basic profile and
design profile for the nut and for the screw . 52
Figure 2a – Gauges for metric thread for nipples . 53
Figure 2b – Gauges for ISO standard pipe thread for nipples . 54
Figure 3 – Gauge for holes for backplate lampholder screws . 55
Figure 4 – Normal operation test apparatus . 56
Figure 5 – Test caps for the test of Clause 18 . 57
Figure 6 – Torque apparatus . 58
Figure 7 – Tumbling barrel . 59

IEC 60238:2016 © IEC 2016 – 3 –
Figure 8 – Impact-test apparatus . 60
Figure 9 – Pressure apparatus . 61
Figure 10 – Ball-pressure test apparatus . 61
Figure 11 – Test cap for the tests of 15.4 and 20.3 . 62
Figure 12 – Bending apparatus . 63
Figure 13 – Test cap A and test cap B for lampholders E14 . 65
Figure 14 – Test cap for lampholders E27 . 66
Figure 15 – Test cap for lampholders E40 . 67
Figure 16 – Standard test finger (according to IEC 60529) . 68
Figure 17 – Clarification of some definitions . 69
Figure 18 – Preparation of specimens for the needle-flame test of 21.4 . 70

Table 1 – Thickness of screw shells and contacts . 18
Table 2 – Minimum effective screw lengths . 18
Table 3 – Dimensions of threaded entries and set screws . 19
Table 4 – Minimum dimensions of pillar-type terminals . 23
Table 5 – Minimum dimensions of screw-type terminals . 24
Table 6 – Pull and torque values . 29
Table 7 – Insertion torque . 31
Table 8 – Minimum and maximum removal torques . 31
Table 9 – Test cap dimensions . 35
Table 10 – Heights of fall . 37
Table 11 – Maximum deformation values . 38
Table 12 – Torque values . 40
Table 13a – Minimum distances for AC (50/60 Hz) sinusoidal voltages: Impulse
withstand category II . 42
Table 13b – Minimum distances for AC (50/60 Hz) sinusoidal voltages: Impulse
withstand category III . 43
Table 14 – Minimum distances for non-sinusoidal pulse voltages. 43
Table 15 – Heating cabinet temperatures . 46
Table A.1 – pH adjustment . 71

– 4 – IEC 60238:2016 © IEC 2016
INTERNATIONAL ELECTROTECHNICAL COMMISSION
____________
EDISON SCREW LAMPHOLDERS
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
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agreement between the two organizations.
2) The formal decisions or agreements of IEC on technical matters express, as nearly as possible, an
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3) IEC Publications have the form of recommendations for international use and are accepted by IEC National
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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 60238 has been prepared by subcommittee 34B: Lamp caps and
holders, of IEC technical committee 34: Lamps and related equipment.
This ninth edition cancels and replaces the eighth edition published in 2004, Amendment 1:
2008 and Amendment 2:2011. This edition constitutes a technical revision.
This edition includes the following significant technical changes with respect to the previous
edition:
a) Addition of a pull test for certain E5 and E10 lampholders.
b) Annex D listing amended requirements/clauses which require products to be retested.

IEC 60238:2016 © IEC 2016 – 5 –
The text of this standard is based on the following documents:
FDIS Report on voting
34B/1852/FDIS 34B/1860/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.
In this standard, the following print types are used:
– compliance statements: in italic type.
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.
– 6 – IEC 60238:2016 © IEC 2016
EDISON SCREW LAMPHOLDERS
1 Scope
This International Standard applies to lampholders with Edison thread E14, E27 and E40,
designed for connection to the supply of lamps and semi-luminaires only.
It also applies to switched-lampholders for use in AC circuits only, where the working voltage
does not exceed 250 V r.m.s.
This standard also applies to lampholders with Edison thread E5 designed for connection to
the supply mains of series connected lamps, with a working voltage not exceeding 25 V, to be
used indoors, and to lampholders with Edison thread E10 designed for connection to the
supply mains of series connected lamps, with a working voltage not exceeding 60 V, to be
used indoors or outdoors. It also applies to lampholders E10 for building-in, for the
connection of single lamps to the supply. These lampholders are not intended for retail sale.
As far as it reasonably applies, this standard also covers lampholders other than lampholders
with Edison thread designed for connection of series-connected lamps to the supply.
NOTE This type of lampholder is for example used in Christmas tree lighting chains.
As far as it reasonably applies, this standard also covers adapters.
This standard also covers lampholders which are, wholly or partly, integral with a luminaire or
intended to be built into appliances. It covers the requirements for the lampholder only. For
all other requirements, such as protection against electric shock in the area of the terminals
or of the lamp cap, the requirements of the relevant appliance standard are observed and
tested after building into the appropriate equipment, when that equipment is tested according
to its own standard. Such lampholders as well as lampholders provided with a snap-on outer
shell, for use by luminaire manufacturers only, are not for retail sale.
This standard applies to lampholders to be used indoors or outdoors in residential as well as
in industrial lighting installations. It also applies to candle lampholders. In locations where
special conditions prevail, as for street lighting, on board ships, in vehicles and in hazardous
locations, for example where explosions are liable to occur, special constructions may be
required.
This standard does not apply to three-light lampholders E26d.
This standard is based on the following data relative to lamps for general lighting service:
– caps E14 are used for lamps with a current not exceeding 2 A;
– caps E27 are used for lamps with a current not exceeding 4 A;
– caps E40 are used for lamps with a current not exceeding 16 A, or 32 A if the nominal
voltage of the supply does not exceed 130 V (see 5.5 and 6.3).
Where lampholders are used in luminaires, their maximum operating temperatures are
specified in IEC 60598.
___________
Requirements for lampholders suitable for semi-luminaires are under consideration.

IEC 60238:2016 © IEC 2016 – 7 –
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 60061-1, Lamp caps and holders together with gauges for the control of
interchangeability and safety – Part 1: Lamp caps
IEC 60061-2, Lamp caps and holders together with gauges for the control of
interchangeability and safety – Part 2: Lampholders
IEC 60061-3, Lamp caps and holders together with gauges for the control of
interchangeability and safety – Part 3: Gauges
IEC 60068-2-32:1975, Basic environmental testing procedures – Part 2-32: Tests – Test Ed:
Free fall
IEC 60068-2-75:2014, Environmental testing – Part 2-75: Tests – Test Eh: Hammer tests
IEC 60112:2003, Method for the determination of the proof and the comparative tracking
indices of solid insulating materials
Amendment 1:2009
IEC 60227 (all parts), Polyvinyl chloride insulated cables of rated voltages up to and
including 450/750 V
IEC 60245 (all parts), Rubber insulated cables – Rated voltages up to and including
450/750 V
IEC 60352-1:1997, Solderless connections – Part 1: Wrapped connections – General
requirements, test methods and practical guidance
IEC 60399, Barrel thread for lampholders with shade holder ring
IEC 60417, Graphical symbols for use on equipment (available at: http://www.graphical-
symbols.info/equipment)
IEC 60529:1989, Degrees of protection provided by enclosures (IP Code)
Amendment 1:1999
Amendment 2:2013
IEC 60598-1, Luminaires – Part 1: General requirements and tests
IEC 60630, Maximum lamp outlines for incandescent lamps
IEC 60695-2-11:2014, Fire hazard testing – Part 2-11: Glowing/hot-wire based test methods
– Glow-wire flammability test method for end-products (GWEPT)
IEC 60695-11-5, Fire hazard testing – Part 11-5: Test flames – Needle-flame test method –
Apparatus, confirmatory test arrangement and guidance
___________
A consolidated edition 2.2 (2013) exists including edition 2.0 (1989) and its Amendment 1 (1999) and
Amendment 2 (2013).
– 8 – IEC 60238:2016 © IEC 2016
IEC 61058-1:2000, Switches for appliances – Part 1: General requirements
ISO 4046-4:2002, Paper, board, pulps and related terms – Vocabulary – Part 4: Paper and
board grades and converted products
3 Terms and definitions
For the purposes of this document, the following terms and definitions apply.
3.1
cord-grip lampholder
lampholder incorporating a method of retaining a flexible cord by which it may then be
suspended
3.2
threaded entry lampholder
lampholder incorporating a threaded component at the point of entry of the supply wires
permitting the lampholder to be mounted on a mating threaded support
Note 1 to entry: A threaded entry lampholder was formerly called a “nipple lampholder”.
3.3
backplate lampholder
lampholder so designed as to be suitable for mounting by means of an associated or integral
backplate, directly onto a supporting surface or appropriate box
3.4
lampholder for building-in
lampholder designed to be built into a luminaire, an additional enclosure or the like
3.4.1
unenclosed lampholder
lampholder for building-in so designed that it requires additional means, for example an
enclosure, to meet the requirements of this standard with regard to protection against electric
shock
3.4.2
enclosed lampholder
lampholder for building-in so designed that on its own it fulfils the requirements of this
standard with regard to protection against electric shock and IP classification, if appropriate
3.5
independent lampholder
lampholder so designed that it can be mounted separately from a luminaire and at the same
time providing all the necessary protection according to its classification and marking
3.6
terminal/contact assembly
part or assembly of parts which provides a means of connection between the termination of a
supply conductor and the contact making surfaces of the corresponding lamp cap
Note 1 to entry: For clarification of some definitions, see also Figure 17.
3.7
outer shell
cylindrical component protecting the user from contact with the lamp cap.
Note 1 to entry: It may or may not be provided with an external screw thread for fixing a shade ring.

IEC 60238:2016 © IEC 2016 – 9 –
Note 2 to entry: For clarification of some definitions, see also Figure 17.
3.7.1
snap-on outer shell
outer shell for screwless assembly which does not contain the screw shell
Note 1 to entry: The lampholder should not be used when the snap-on outer shell is removed. It is therefore
recommended to place an approval mark, if provided, in such a way that it is not visible when this type of outer
shell is removed.
3.8
screw shell
cylindrical component having an internal screw thread of Edison form for the retention of the
corresponding lamp (cap)
Note 1 to entry: In some constructions, the screw shell is permanently fixed to or integral with the outer shell.
Note 2 to entry: For clarification of some definitions, see also Figure 17.
3.9
insulating ring
cylindrical intermediate piece of insulating material separating a metal screw shell and a
metal outer shell
Note 1 to entry: For clarification of some definitions, see also Figure 17.
3.10
shade ring
cylindrical component having an internal thread or other means to engage a corresponding
support on the outer shell and intended to carry or retain a shade
Note 1 to entry: For clarification of some definitions, see also Figure 17.
3.11
dome
part of a cord-grip lampholder or threaded entry lampholder which shields the connecting
terminals
Note 1 to entry: For clarification of some definitions, see also Figure 17.
3.12
basic insulation
insulation applied to live parts to provide basic protection against electric shock
Note 1 to entry: Basic insulation does not necessarily include insulation used exclusively for functional purposes.
3.13
supplementary insulation
independent insulation applied in addition to basic insulation in order to provide protection
against electric shock in the event of a failure of basic insulation
3.14
double insulation
insulation comprising both basic insulation and supplementary insulation
3.15
reinforced insulation
single insulation system applied to live parts, which provides a degree of protection against
electric shock equivalent to double insulation under the conditions specified
Note 1 to entry: The term "insulation system" does not imply that the insulation is one homogeneous piece. It may
comprise several layers which cannot be tested singly as supplementary or basic insulation.

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3.16
live part
conductive part which may cause an electric shock
3.17
type test
test or series of tests made on a type test sample, for the purpose of checking compliance of
the design of a given product with the requirements of the relevant standard
3.18
type test sample
sample consisting of one or more similar specimens submitted by the manufacturer or
responsible vendor for the purpose of a type test
3.19
semi-luminaire
unit similar to a self-ballasted lamp but designed to utilize a replaceable light source and/or
starting device
3.20
rated operating temperature
highest temperature for which the holder is designed
3.21
rated minimum temperature
lowest temperature for which the holder is designed (applicable only to lampholders intended
for use in refrigerators and food freezers)
3.22
angled lampholder
lampholder, the rear side of which (threaded entry and/or dome) is at an angled position to
the screw shell axis
3.23
lampholder with retention device
lampholder with a device intended to prevent the lamp from becoming loose in the holder
Note 1 to entry: Lamps can, for example, become loose due to changes in temperature or to vibrations.
3.24
impulse withstand category
numeral defining a transient overvoltage condition
Note 1 to entry: Impulse withstand categories I, II, III and IV are used.
a) Purpose of classification of impulse withstand categories
Impulse withstand categories are to distinguish different degrees of availability of equipment with regard to
required expectations on continuity of service and on an acceptable risk of failure.
By selection of impulse withstand levels of equipment insulation, co-ordination can be achieved in the whole
installation, reducing the risk of failure to an acceptable level providing a basis for overvoltage control.
A higher characteristic numeral of an impulse withstand category indicates a higher specific impulse withstand
of the equipment and offers a wider choice of methods for overvoltage control.
The concept of impulse withstand category is used for equipment energized directly from the mains.
b) Description of impulse withstand categories
Equipment of impulse withstand category I is equipment which is intended to be connected to the fixed
electrical installations of buildings. Protective means are taken outside the equipment – either in the fixed
installation or between the fixed installation and the equipment – to limit transient overvoltages to the specific
level.
Equipment of impulse withstand category II is equipment to be connected to the fixed electrical installations of
buildings.
IEC 60238:2016 © IEC 2016 – 11 –
Equipment of impulse withstand category III is equipment which is part of the fixed electrical installations and
other equipment where a higher degree of availability is expected.
Equipment of impulse withstand category IV is for use at or in the proximity of the origin of the electrical
installations of buildings upstream of the main distribution board.
3.25
primary circuit
circuit which is directly connected to the AC mains supply
Note 1 to entry: It includes, for example, the means for connection to the AC mains supply, the primary windings
of transformers, motors and other loading devices.
3.26
secondary circuit
circuit which has no direct connection to a primary circuit and derives its power from a
transformer, converter or equivalent isolation device, or from a battery
Note 1 to entry: Exception: autotransformers. Although having direct connection to a primary circuit, the tapped
part of them is also deemed to be a secondary circuit in the sense of this definition.
Note 2 to entry: Mains transients in such a circuit are attenuated by the corresponding primary windings. Also
inductive ballasts reduce the mains transient voltage height. Therefore, components located after a primary circuit
or after an inductive ballast can be suited for an impulse withstand category of one step lower, i.e. for impulse
withstand category II.
3.27
adapter
component used for the electrical and mechanical connection of a lamp to a lampholder
Note 1 to entry: This definition is specific for this standard. The definition of an adapter in principle could vary
very much depending on its use. In most cases such a component is used to bridge differences in the screw thread
diameter between the lampholder and the lamp.
3.28
enclosed reinforced insulated lampholder
lampholder for building-in so designed that on its own it fulfils the requirements for double or
reinforced insulated parts in class II applications
3.29
partly reinforced insulated lampholder
lampholder for building-in so designed that some parts of the lampholder require additional
means to fulfil the requirements with regard to double or reinforced insulation
Note 1 to entry: In some cases, the dimensions might be achieved only after mounting into the luminaire.
4 General requirement
Lampholders shall be so designed and constructed that in normal use they function reliably
and cause no danger to persons or surroundings.
In general, compliance is checked by carrying out all the tests specified.
In addition, the enclosure of independent lampholders shall comply with the requirements of
IEC 60598-1, including the classification and marking requirements of that standard.
5 General conditions for tests
5.1 Tests according to this standard are type tests.
NOTE The requirements and tolerances permitted by this standard are related to testing of a type test sample
submitted for that purpose.
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Compliance of the type test sample does not ensure compliance of the whole production of a manufacturer with
this safety standard.
In addition to type testing, conformity of production is the responsibility of the manufacturer and can include
routine tests and quality assurance.
For further information on conformity testing during manufacture see IEC 60061-4.
5.2 Unless otherwise specified, the tests are made at an ambient temperature of 20 °C ±
5 °C and with the holder tested as delivered and installed as in normal use.
5.3 The tests and inspections are carried out on a total of
– nine specimens for non-switched lampholders, or
– 12 specimens for switched lampholders
in the following order of clauses:
– three specimens: Clauses 2 to 13 (except for 10.1 and 11.2) and Clauses 15 to 18;
– three specimens: Clause 14 (switched-lampholder tests only);
– three specimens: 10.1 and Clauses 19 and 20;
– two specimens: Clause 21 (of which one specimen for the test of 21.1 and the other for
the tests of 21.3 or 21.4);
– one specimen: 21.5 and Clause 22.
For testing lampholders with a retention device, the retention device shall be removed.
For testing lampholders with a retention device according to 13.14, three additional
specimens are required with the retention device kept in place.
For testing of screwless terminals according to 11.2, separate specimens are required in
addition.
5.4 In case of doubt, gauges, test caps and mandrels are introduced into the specimens,
unless otherwise specified, by applying the following torques:
– 0,2 Nm for lampholders E5;
– 0,2 Nm for lampholders E10;
– 0,2 Nm for lampholders E14;
– 0,4 Nm for lampholders E27;
– 0,8 Nm for lampholders E40.
5.5 For lampholders E40 with a rated current of 32 A, the tests shall be based on this rated
current.
5.6 Lampholders are deemed to comply with this standard if no specimen fails in the
complete series of tests specified in 5.3.
If one specimen fails in one test, that test and the preceding ones which may have influenced
the result o
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