Dictionary of Electrical Engineering

Commonly used terms in the Electrical industry.

ballast
a starting and control mechanism for fluorescent and other types of gas-discharge lamps. Initially a ballast supplies the necessary starting (or striking) voltage in order to ionize the gas to establish an arc between the two filaments in the lamp. Once the gas is ionized, the ballast controls the input power and thus the light output to maximize the efficiency and life of the lamp.