What's the use of fluorescent starter in fluorescent lamp?

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Update time : 2016-08-26 11:15:19
Only use magnetic ballasts only use fluorescent starter, starter role is to produce self-inductance high-voltage breakdown inside the tube of the gas moment (containing mercury vapor low-pressure inert gas) after the end of warm fluorescent, thereby so that the lamp starts. The specific process is this: just when the fluorescent lamp is energized, the gas inside the tube in the absence of ionizing case in a high impedance state, then no current flows through the lamp, ballast and therefore the coil (Figure L) no partial pressure, 220V voltage directly added to the tube ends, but not enough to make the lamp voltage of 220V start, so at this time the lamp does not emit light. Note, however, connected in series between two lamp filament starter has also been added 220V voltage, starter inside the neon bulb at 150V can occur glow discharge, so at this starter started inside discharge, emit blue-violet light (transparent plastic case of the starter is energized so that you can see just the starter will flash a few times), in this process, the neon bulb temperature, the internal bimetal thermal deformation, approximately 2 seconds around collide with the fixed contacts, the latter two contacts, the starter is short-circuited, then the current through the ballast - filament - starter - back into the filament constituting the loop current is large (in this case two lamps end of the filament emits orange-yellow light). After a short circuit the starter, glow discharge process is stopped, no longer heating, cooling bimetal restore the original shape, bimetal and metal bar separating the moment, the starter circuit is disconnected, the circuit current moment reduced, but due to the ballast inductance L is actually a core, a huge self-induced emf inductor current decreases resistance in the process of reducing the speed of the current process (capacitor voltage can not change suddenly, the inductor current can not mutation) this self-inductance high pressure may reach several thousand volts, will penetrate the gas inside the lamp immediately after breakdown inside the tube is ionized, the lamp voltage drop decreases rapidly, current flows (before the starter is inside the tube flow but does not flow through the filament inside the tube), by limiting the role of ballast, the voltage across the lamp drops to about 100V, the starter no longer works due to insufficient voltage, the lamp enters the normal luminous state. After the starter, the starter will no longer play a role, even if the removal of the lamp does not go off.