Definition for word: Ballast

A device used to provide the starting voltage or to stabilize the current in a circuit. Commonly used for fluorescent and CFL-type lightbulbs.

Referrence from

An electrical ballast (sometimes called control gear) is a device intended to limit the amount of current in an electric circuit.

Ballasts vary greatly in complexity. They can be as simple as a series resistor as commonly used with small neon lamps or light-emitting diodes (LEDs). For higher-power installations, too much energy would be wasted in a resistive ballast, so alternatives are used that depend upon the reactance of inductors, capacitors, or both. Finally, ballasts can be as complex as the computerized, remote-controlled electronic ballasts now often used with fluorescent lamps.

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