Why Do Fluorescent Lights Hum?


Quick Answer

Fluorescent light fixtures hum when they have a magnetic, rather than electronic, ballast. The noise is caused by the magnetic ballast vibrating at a frequency of 60 hertz.

Continue Reading
Related Videos

Full Answer

Magnetic ballasts, also known as transformers, have relatively low cycle rate modulating the alternating current in the fluorescent tube, which often results in a noticeable flickering of the light source. The simplest solution to avoid these effects is to replace the magnetic ballast with a modern electronic ballast which operates at 20,000 to 60,000 hertz. Additionally, electronic ballasts conserve electricity better; magnetic ballasts can waste up to 10 percent of a lamp's input power.

Learn more about Lighting

Related Questions