The Research And Development Of Eol Effect And Power Testing System For Ex”en Lfuorescent Lamps

The fluorescent lamps designed by Ex "e" are widely used in the petrochemical industry and other flammable and combustible areas.However, it appear a new kind of abnormal condition when was in operation in recent years,that is rectifying phenomenon caused by the End Of Life effect, which can make lamps produce local high temperature, even make the tube melt to explode.IEC introduced new standards and testing methods aimed at this condition.Because of low degree of automation by traditional testing methods,a system was designed for measuring the power of the electronic ballasts based on the explosion-proof technology of fluorescent lamps designed by Ex "e"and the technology of virtual instrument.The specific research work is as follows:1. Based on the basal explosion-proof technology, the requirements of lamps designed by Ex "e" and the process of rectifying-effect caused by EOL of fluorescent lamps are introduced. According to different rectifying-effects,three different testing methods including the asymmetric pulse method,the asymmetric power method and the break filament method are deeply researched.2. Parameters of the asymmetric pulse circuit are analysed, according which the hardware part of the power measurement system is designed,including the sample circuit,signal regulated circuit,driver circuit and the selection of DAQ Card.The functions of data acquisition and communication are realized.3. Based on the technology of virtual instrument,a friendly human-machine interface is designed, including the modules of data displaying,data storage,digital I/O controlling and the timers while according to the steps of the testing process.Compared with the traditional testing methods,the power testing system can realize the functions of testing three sets of fluorescent lamps at the same time,it effectively improve the testing efficiency.