BASICS 7 of 19

All discharge lamps: Fluorescent, HID, etc. require a ballast to operate them. One end of the ballast plugs into the electrical line. The other end has wires going to the lamp.

Linear fluorescent lamps can be operated on Electronic or Magnetic ballasts. A single fluorescent ballast may operate up to 4 lamps. Ballasts last many years--typically 10 to 15 years. Lamps fail much more frequently than ballasts.

Most HID lamps are operated on Magnetic ballasts which contain a Capacitor and a "Core and Coil" unit that looks like a transformer—with iron core and copper windings. HID ballasts typically operate just one lamp.

Ballasts generate very high voltages which can be lethal. Only trained electricians should work with ballasts!

Always disconnect power completely before working with a ballast.