Lighting
Ballast
A ballast is a device that starts a fluorescent or HID lamp and limits the current flowing through it.
Gas discharge lamps cannot run directly on line power. A ballast gives them a starting voltage and then regulates the current. Magnetic ballasts are older and electronic ballasts are newer. The ballast uses power too: in one Department of Energy example, a 250 watt metal halide lamp draws 288 watts together with the ballast.
LED lamps use a driver instead. When a fixture is retrofitted, a ballast may be bypassed or replaced, which is wiring work for a licensed electrician. See HID lighting and parking lot lighting repair.
Related terms
Sources
TECL #21005 · Family owned since 1988
Need an electrician in Southlake?
Call and tell us what is going on. A photo of the panel label or the problem helps us come prepared. Quotes on new installations are free.
