In my home
40W fluorescent lamp use more than 3 years,it's not too bad a, but every six months or so to change an electronic ballast and
electronic ballast prices to not expensive, 2-3USD, the most expensive 5 USD, but life is short, a few years down to change a lot, open ballast found that all is start capacitor is damaged.
The reason is the capacitor, open lamp will produce high voltage glow lamp, ballast is the most easily damaged components, the performance of this element is to judge the attention pressure value must reach 1200V, in order to ensure the service life, most of the manufacturers in order to save costs, the use of 400V capacitor, the capacitor damage is greatly shortened life expectancy breakdown system, open circuit board, see the capacitor and the lamp is collusion, judging whether the capacitance breakdown, using multimeter resistance profile measurement of a points and B points, infinity is in good condition, has indicated that the circuit breakdown pathway out of the picture, you see, C5 is a starting capacitor, 40W lamp start-up capacity is 682J, 6N8J, 332J 472J, 32W, the capacity is 332J, can be interchanged, such as U type energy-saving lamp tube has a starting capacitor of the same type, but mostly because such small tube power is 332J, the usual collection of polyester capacitors, the ballast is broken, change starting capacitor, indeed save a lot of cost. But note that a point is the best voltage is 1200W, the life is guaranteed, but also hope that manufacturers attach importance to this element, or more reasonable research and development of the circuit, so that the real role of daylight saving energy!
capacitor values 332J is ceramic capacitors, polyester capacitors are usually labeled method, the default value is PF, the last 2 showed that number of times square, can also be considered to be the number of zeros, J said error is plus or minus 5%, if K is the margin of error of plus or minus 10%, 332J said 3300pf capacitors, error of plus or minus 5%, but most of the capacitance is f (micro method), so this capacitor is 0.0033 u F