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This work presents a study of lamps characterization concerning its lamp output, current and voltage drift during
seasoning and regarding the use of theses lamps as luminous flux secondary standard. The 200W halogen lamps are
seasoned for 30 hours and during the seasoning period the relative drift of the lamp illuminance, current and voltage are
measured at each 3 minutes. The illuminance is measured using a photometer with detector head, the lamp voltage is
measured using a 6.5 digits voltmeter and the current is measured using a 6.5 digits voltmeter and 0.1 Ohms standard
resistor. The lamp current is controlled by a calibrated current power source with stability better than 1 mA. To reduce
the stray light, baffles are positioned between the lamp and the detector head. The alignment of experimental assembly is
made by a He-Ne Laser. Data of illuminance, current and voltage is acquired by software built in Labview database.
Among the 5 lamps seasoned, the best result presents the variation of illuminance of 0.04% per hour. This lamp is
chosen to become the secondary standard and its luminous flux is measured using an Ulbricht integrating sphere. This
method allows the laboratory to create secondary standard of luminous flux for its routine test and measurements and to
supply theses standards for Brazilian industry.
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