China manufacturer of magnetic ballasts for metal halide flood lights & hps flood lights

Yes, there is a specially-designed dimmer switch that will work with somefluorescent fixtures. However, this type of dimmer is "ballast-dependent", meaning that each brand of fluorescent dimmer will only work with certain ballasts from certain manufacturers. In other words, trying to find a dimmer to match your fixture may be a mind-numbing chore. The ideal situation is to choose the dimmer and the light fixture together to assure compatibility. Also, these dimmers will not work for incandescent fixtures.

A fluorescent lamp ballast is an electrical transformer. Fluorescent lamps require different voltages at different places in the lamp in a standard rapid start system. There are small filaments at the end of the lamp that require low voltage (approx. 4 volts) to aid in starting the lamp, this is called cathode voltage. The lamp also requires a higher voltage (200 volts or higher depending on lamp type) from end to end on the lamp to operate, this is called arc voltage. The ballast transforms line voltage 120 volts to these requirements. The ballast limits the amount of current that the lamp can draw. This prevents the lamp from drawing too much current and failing.

Recently,electronic ballasts based on digital electronics have become available for Metal Halide lamps (manufactured by James Lighting Industries (for 175W and 250W bulbs). The hps ballasts and mh ballasts have been shown to be more efficient, than the standard MH ballasts.