This International Standard specifies performance requirements for electronic step-down convertors for use on d.c. supplies up to 250 V and a.c. supplies up to 1 000 V at 50 Hz or 60 Hz with operating frequencies deviating from the supply frequency, associated with tungsten halogen lamps as specified in IEC 60357 and other filament lamps.NOTES1 The tests in this standard are type tests. Requirements for testing individual convertors during production are not included.2 Requirements for convertors which Incorporate means for varying the lamp power are under consideration.3 It may be expected that convertors complying with this standard will ensure satisfactory operation between 92% and 106% of rated supply voltage of filament lamps with rated lives greater than 200 hours and rated voltage less than 50 V.This standard is to be read in conjunction with IEC 61046 AS/NZS 61046.