An electrical ballast is a device intended to limit the amount of current in
an electric circuit. A familiar and widely used example is the inductive ballast
used in fluorescent lamps, to limit the current through the tube.
An inductor is very common in line-frequency ballasts to provide the proper
starting and operating electrical condition to power a fluorescent lamp, neon
lamp, or high intensity discharge (HID) lamp. (Because of the use of the
inductor, such ballasts are usually called magnetic ballasts.) The inductor has
- Its reactance limits the power available to the lamp with only minimal power
losses in the inductor
- The voltage spike produced when current through the inductor is rapidly
interrupted is used in some circuits to first strike the arc in the lamp.
An electronic ballast uses solid state electronic circuitry to provide the
proper starting and operating electrical conditions to power discharge lamps. An
electronic ballast can be smaller and lighter than a comparably-rated magnetic
|Click on the picture below to see more lighting ballast