Most magnetic ballasts for T5FT lamps are designed specifically for use with these lamps. Some manufacturers offer ballasts designed specifically for T5FT lamps, but most manufacturers suggest using ballasts that will also operate T12 or T8 lamps. Again, some manufacturers offer dimming electronic ballasts designed specifically for T5FT lamps, while others recommend using ballasts that will also operate T12 or T8 lamps. Table 2 shows the availability of ballasts for T5FT lamps. The specifier must choose either a magnetic or electronic ballast.
Electronic ballasts offer greater lamp efficacy than magnetic ballasts, but are more expensive.
High-frequency electronic ballasts also produce less noise, heat, and flicker than magnetic ballasts. Electronic Ballasts for more information on electronic ballasts. Although preheat ballasts are becoming outdated, they are relatively inexpensive. Some kinds of luminaires, particularly task lights, have preheat ballasts built into them. Rapid-start ballasts heat the lamp's electrodes before starting the lamp, and usually continue to heat the electrodes while the lamp is operating.