what is ballast used for
This is kind of a broad explanation of ballasts in general, as the term originally did not apply to HID lights. Originally, the term ballast was used to describe large inductors used to limit AC current for fluorescent lighting and other gas-discharge lights (especially sodium vapor and mercury vapor streetlights).
A ballast provides. the starting voltage for a fluorescent lamp and limits. the current passing through it. The ballast also provides. proper electrode or filament heating. For most of the last century, electromagnetic ballasts, sometimes referred to as âcore-and-coilâ or âmagneticâ. ballasts, were the only fluorescent lamp ballasts. available. Since 1988, when they first began to. penetrate the market, electronic ballasts have proven. themselves not only as workhorses of efficiency but.
A ballast water system is essential for the safe operation of a ship, but the operation of these systems causes significant threats to the environment and local economy. A ballast water system allows a ship to pump water in and out of very large tanks to compensate for a change in cargo load, shallow draft conditions, or weather. 1  The capacity of ballast water tanks might be millions of gallons on a large vessel.