the Study on the Presumption of the Life of the Fluorescent Lamp

There are many factors affecting the life of the fluorescent lamp, and the consumption of the oxide coated upon the electrode filament is most closely related with its absolute life., Connecting the voltmeter to the terminals of a filament, some voltage appears between them. As it seems that the filament voltage has trelation to the consumption of the oxide, the author researched its phenomena at D. C. and A. C. lighting of the fluorescent lamp. As the result of the qualitative and quantitacive investigation, it was confir-med that the filament voltage was the voltage drop which yeas produced at the filament owing to the current flowing through it. From this result, it was found that by the measurement f the cathode filament voltage, we could know the degree of the consumption of the electrode and also presume the life in a extremely short time.