IEC 60238:2004/AMD2:2011

IEC 60238 ®
Edition 8.0 2011-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
AMENDMENT 2
AMENDEMENT 2
Edison screw lampholders
Douilles à vis Edison pour lampes

IEC 60238:2004/A2:2011
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IEC 60238 ®
Edition 8.0 2011-02
INTERNATIONAL
STANDARD
NORME
INTERNATIONALE
AMENDMENT 2
AMENDEMENT 2
Edison screw lampholders
Douilles à vis Edison pour lampes

INTERNATIONAL
ELECTROTECHNICAL
COMMISSION
COMMISSION
ELECTROTECHNIQUE
INTERNATIONALE PRICE CODE
G
CODE PRIX
ICS 29.140.10 ISBN 978-2-88912-387-2

– 2 – 60238 Amend.2 © IEC:2011
FOREWORD
This amendment has been prepared by subcommittee 34B: Lamp caps and holders, of IEC
technical committee 34: Lamps and related equipment.
The text of this amendment is based on the following documents:
FDIS Report on voting
34B/1577/FDIS 34B/1593/RVD
Full information on the voting for the approval of this amendment can be found in the report
on voting indicated in the above table.
The committee has decided that the contents of this amendment and the base 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• withdrawn,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.
_____________
2 Definitions
Add the following two new definitions:
2.28
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
2.29
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 In some cases, the dimensions might be achieved only after mounting into the luminaire.

60238 Amend.2 © IEC:2011 – 3 –
6 Classification
Replace the existing Subclause 6.5 by the following:
6.5 According to protection against electric shock
− unenclosed lampholders;
− enclosed lampholders;
− independent lampholders;
− partly reinforced insulated lampholders;
− enclosed reinforced insulated lampholders.
NOTE Where a lampholder is used with a working voltage of 50 % or less of its maximum rating, it may be
regarded as equivalent to a reinforced insulated lampholder.
7 Marking
Replace, in Subclause 7.1, the fourth paragraph (“Lampholders complying with the…”),
Note 3 and the fifth paragraph, added by Amendment 1, by the following new text:
Enclosed reinforced insulated lampholders offer an adequate level of protection for use in
luminaires where they are accessible in normal use. This information shall be indicated in the
manufacturer’s catalogue or the like.
For partly reinforced insulated lampholders, sufficient creepage distances and clearances to
outer accessible surfaces will require additional protection to some parts of the lampholder by
the luminaire design or by use of additional attachment(s) or cover(s). This information shall
be indicated in the manufacturer’s catalogue or the like.
Add the following new Note 3 to Subclause 7.1 below the first indent “- type reference”:
NOTE 3 Available technical documentation of the manufacturer like printed catalogues or online catalogues
should allow a clear identification of a lampholder either by a unique catalogue number or by an identifying
reference on the holder, specifying the essential characteristic features and the basic design of the product
supplemented by a clear description. Variations of the basic design like for example different cable length, fixing
means, colours etc., which do not affect safety or performance of the lampholder, may be disregarded in the type
reference marked on the product. Variations included in the type testing procedure are listed in the corresponding
test reports.
Add the following new Note 4 to Subclause 7.1 below the second indent “- type reference”:
NOTE 4 Note 3 applies.
Add the following new Note 5 to Subclause 7.1 below the thirdindent “- type reference”:
NOTE 5 Note 3 applies.
Renumber the existing last note as Note 6.

– 4 – 60238 Amend.2 © IEC:2011
14 Moisture resistance, insulation resistance and electrical strength
14.4 Replace the tenth paragraph (“Immediately after the insulation…”) by the following new
paragraph:
Immediately after the insulation resistance test, an a.c. voltage of substantially sine wave
form, with a frequency of 50 Hz or 60 Hz and with an r. m. s. value of (2 U + 1 000) V (where
U is the rated voltage) is applied for 1 min between the points prescribed. For enclosed and
unenclosed reinforced insulated lampholders, the test voltage shall be determined from
Table 10.2 of IEC 60598-1. Additionally, for switched lampholders, this voltage shall be
applied between live parts of different polarity and other metal parts with the switch both
closed and open.
17 Creepage distances and clearances
Replace the existing Table 13a by the following new table:

Rated voltage
Distances
V
mm
50 150 250 4)
1 Between live parts of different polarity, and
2 Between live parts and external metal parts, if not
covered with insulating material:

(this includes screws of backplate lampholders)

Basic insulation
- Creepage distances
1)
0,6 0,8 1,5 3
insulation PTI ≥ 600
1)
PTI < 600
1,2 1,6 2,5 5
4) 0,2 0,8 1,5 3
- Clearances
Reinforced insulation
- Creepage distances
1)
- 1,6 3 6
insulation PTI ≥ 600
1)
PTI < 600
- 3,2 5 6
4) - 1,6 3 6
- Clearances
3 Clearances for backplate lampholders *
- between live parts of different polarity, and
- between live parts and the boundary of the
space for the supply wires in backplate

lampholders not specifically intended for
building in:
0,6 0,8 1,5 3
NOTE Values for creepage distances and clearances may be found for intermediate values of rated voltages by
linear interpolation between tabulated values. No values are specified for rated voltages below 25 V as the
voltage test of 14.4 is considered sufficient.
* These values take account of possible unevenness of the mounting surface.

60238 Amend.2 © IEC:2011 – 5 –
Annex B – Guidance for requirements in IEC 61058-1 applicable to switches in
lampholders (see 13.2)
7.1.4 According to number of operating cycles
Replace the existing first paragraph by the following:
Only 7.1.4.4 is applicable.
Figure 1a – Nipple thread for lampholders. Basic profile and design profile for the nut
and for the screw
Replace the existing Figure 1a by the following new Figure 1a:
Metric thread
h = 0,866 03 s
s
h/4 = 0,216 51 s
h/8 = 0,108 25 s
60°
h/8
t0 = 5/8h = 0,541 27 s
h/2
30°
t0
h
h/4
IEC  452/11
Basic profile*
* The basic profile is the profile to which the deviations defining the limits of the external and the internal threads
are applied.
Design profile for th
...