What is the connection of the ballast
Electronic ballast is a converter that converts the frequency ac power to high frequency ac power supply. The mains power supply is converted into a dc power source by rf interference (RFI) filter, full wave rectifier and passive (or active) power factor corrector (PPFC or APFC). Through the DC/AC converter, the output of 20 k - 100 KHZ high frequency AC power, added to the LC series resonance circuit, which is connected with lamp heating filament, but make tubes "discharge" "conduction" state, then enter a state of luminescence, high frequency inductive limit the increase of current role at this time, guarantee the normal work of the tubes for the lamp voltage and lamp current, in order to improve the reliability, often add various protection circuit, such as abnormal protection and surge voltage and current protection, temperature protection and so on.
When the switch is closed circuit of 220 v, 50 hz ac power, the electric current flows through the ballast, lamp filament to the starter filament heating (at the beginning of the starter is broken, due to exert a greater than 190 v ac voltage, the starter has jump of gas inside the bubble inside the arc discharge, the bimetallic strip heating deformation, two electrodes together, form a path to the filament heating), when the starter of the two electrodes together, since there is no arc discharge, bimetallic strip cooling, poles apart, due to the inductance ballasts are perceptual, when the circuit is suddenly interrupted, duration on both ends of the lamp will produce about 1 ms pulse voltage 600 v to 600 v, the exact voltage value depends on the kind of light, in the case of discharge, the ends of the lamp voltage drop, immediately the lamp current limiting effect on the ballast on the one hand, on the other hand make the supply voltage and the working current of the lamp produces 55.- 65.The phase difference of the lamp, which keeps the lamp's secondary start voltage, makes the lamp more stable.
Is fluorescent lamp ballast, ballast resistor) on the current limiting effect and the production of instantaneous high pressure equipment, it is enameled wire on the core of silicon steel production, the iron core coil, open/close the electricity in an instant, can produce high voltage, self inductance on the electrodes at the ends of the tube (filament). This movement is alternating, when the regenerator (bubble) closes, the filament of the lamp passes through the ballast. When open the starter and ballast can produce high feeling on the ends of the tube filament, filament electron bombardment wall of fluorescent powder, repeated several times to break the starter, such movement will be repeated several times, to get through tubes. When lamp normal luminescence, smaller resistance, always keep open state, the starter of the electric current is stable through work lamp, ballast, lamp to normal light. Due to the ballast in fluorescent lamp work, there is always an electric current passes through, so prone to vibration, and fever, so have a ballast of fluorescent lamp, especially the ballast quality is bad, will produce very big voice, use a long time, also easy to burn out. Ballast electronic ballast and inductance ballast.
