IS 8913 : 2025/IEC 60360 : 1998 Standard Method of Measurement of Lamp Cap Temperature Rise
NATIONAL FOREWORD
This Indian Standard (First Revision) which is identical to IEC 60360 : 1998 'Standard method of measurement of lamp cap temperature rise' issued by the International Electrotechnical Commission (IEC) was adopted by the Bureau of Indian Standards on the recommendation of the Lamps and Related Equipments Sectional Committee and approval of the Electrotechnical Division Council.
This standard was first published in year 1978 to align it with the IEC 60360 : 1971. This first revision has been brought out to align it with the latest version of IEC 60360 : 1998.
This edition includes the following significant technical changes with respect to the previous edition:
The temperature rise of the lamp cap of a tungsten filament lamp is, in practice, very dependent on the mounting of the lamp and the condition of the cap.
For this reason, it has been necessary to define a method of measurement based on the use of a standard test lampholder. The temperature rise Δts, measured on the standard test lampholder is then taken as the lamp cap temperature rise for the purpose of this standard.
Compared with the measurement of the temperature rise of the bare lamp cap, the measurement of the temperature rise of a standard test lampholder has the following advantages:
a) A better approximation to actual operating conditions;
b) Improved reproducibility, as there is less influence from lamp cap material, finish and surface conditions (which also have little influence in actual operating conditions);
c) Levelling of the temperature of various parts of the cap, giving a better over-all picture of the influx of heat from the lamp to the fitting; and
d) Reduced duration of measurements, as the thermocouple is permanently fixed to the test lampholder.
The text of the IEC standard has been approved as suitable for publication as an Indian Standard without deviations. Certain conventions are, however, not identical to those used in Indian Standards. Attention is particularly drawn to the following:
a) Wherever the words 'International Standard' appears referring to this standard, they should be read as 'Indian Standard'; and
b) Comma (,) has been used as a decimal marker, while in Indian Standards the current practice is to use a point (.) as the decimal marker.