Ballasts: 3 of 21

In the early days all ballasts were electromagnetic--also referred to simply as "magnetic." They had coils and transformers. Attempts to improve them resulted in "high efficiency" ballasts and "super high efficiency" ballasts, and so on. Today they are all considered inefficient ballasts!

The electronic ballast was a breakthrough. Since the 1980's electronic ballasts have been gradually taking over the fluorescent market.

Indeed from the year 2005 electromagnetic ballasts can no longer be shipped to fixture manufacturers for use in 4 ft. and 8 ft. linear fluorescent fixtures.

A single electronic ballast can operate up to 4 lamps.
Lamps can be wired in SERIES or PARALLEL.