Ballast is 1) heavy material such as sand or stone that is used at the bottom of a ship to ensure its stability; 2) a device used to control the voltage in a fluorescent lighting system to provide sufficient voltage to start the lamps.
Ballast is 1) heavy material such as sand or stone that is used at the bottom of a ship to ensure its stability; 2) a device used to control the voltage in a fluorescent lighting system to provide sufficient voltage to start the lamps.