Ballasts are devices required for the operation of gas lamps (including fluorescent lamps, metal halide lamps, and high pressure sodium lamps). Ballasts provide the initial starting voltage to a gas lamp. The initial starting voltage provided by the ballasts creates an electrical arc that excites the gases in the lamp, thus producing light. In the cases of pre-heat and rapid start circuits, ballasts heat the electrodes in the lamp allowing for arc discharge. After the ballasts provide the initial starting voltage the ballasts regulate voltage at an optimal level for lamp operation. Ballasts compensate for voltage fluctuations during lamp operation.
Fluorescent Ballasts: There are two general, broad categories of fluorescents ballasts-Magnetic Ballasts and Electronic Ballasts.
Magnetic Ballasts: Magnetic ballasts are also called inductive or electromagnetic ballasts. Magnetic Ballasts us an aluminum coil wrapped around an iron core to generate and regulate voltage. Since 1988 congress has regulated the efficacy factors of magnetic ballasts (making magnetic ballasts much more efficient). Despite regulations determining efficiency of magnetic ballast, they are still considered the least efficient types of fluorescent ballasts. Although magnetic ballasts are still very common, over the next several years manufactures will begin to phase out magnetic ballasts for electronic ballasts. Magnetic ballasts are susceptible to humming and flickering. Magnetic ballasts operate T12 lamps (including bi-pin, single-pin, and high output), some T8 lamps, and 2-pin compact fluorescent lamps. Magnetic ballasts are available in 1 and 2 lamp configurations.
Electronic Ballasts: Electronic ballasts use solid state electronic circuitry to regulate starting voltage and to maintain proper operating current. Electronic ballasts produce light more efficiently than magnetic ballasts. Electronic ballasts are up to 25% more efficient than magnetic ballasts. Another advantage of electronic ballasts is that they eliminate visible flicker and audible hum. Electronic ballasts can operate from one to four lamps at a time. Electronic ballasts are most commonly used for T8 fluorescents and T5 fluorescents. Electronic ballasts are now being made to operate T12 fluorescents in both standard and high output. Over time, electronic ballasts will replace magnetic ballasts entirely.
T5 Fluorescent Ballasts: T5 fluorescent ballasts operating either standard output or high output T5 lamps are available. The vast majority of T5 fluorescent lamps are electronic. Because they are electronic, T5 fluorescent ballasts are extremely efficient and have no visible flicker or audible hum. T5 fluorescent ballasts are available in one to four lamps configurations. T5 fluorescent ballasts accept multiple input voltages (120-277).
T8 Fluorescent Ballasts: T8 fluorescent ballasts are available to operate both standard output and high output T8 lamps. All of the T8 fluorescent ballasts listed in our T8 fluorescent ballasts section are electronic. Because they are electronic, all of our T8 fluorescent ballasts are very efficient and have no audible hum or visible flicker. T8 fluorescent ballasts are available in one to four lamp configurations. We offer T8 fluorescent ballasts in dedicated voltage (120 or 277) or universal voltage (120-277).
T12 Fluorescent Ballasts: T12 fluorescent ballasts are available to operate both standard output and high output T12 lamps. Traditionally, T12 fluorescent ballasts have been magnetic ballasts only, but now some T12 fluorescent ballasts are being manufactured as electronic ballasts. These new electronic T12 fluorescent ballasts offer the same advantages as all electronic ballasts (no audible hum, no visible flicker, and energy efficiency). Soon all T12 fluorescent ballasts will be electronic.
High Output Fluorescent Ballasts: High output fluorescent ballasts operate high output fluorescent lamps. High output fluorescent ballasts should never be used to power standard fluorescent lamps. Cold weather conditions and industrial environments are the most common applications for high output fluorescent ballasts. Typical high output fluorescent ballasts will start a lamp at temperatures as low as -20 Fahrenheit. Traditionally, all high output fluorescent ballasts have been magnetic ballasts, however some are now electronic, and soon all high output fluorescent ballasts will be electronic. High output fluorescent ballasts are available in both 1 and 2 lamp configurations. Dedicated voltage ballasts, either 120 or 277 volt, are most common with high output fluorescent ballasts.
Fluorescent Sign Ballasts: Fluorescent sign ballasts are high output fluorescent ballasts. Fluorescent sign ballasts are designed to operate a wide variety of lengths and number of lamps. Fluorescent sign ballasts may operate up to six lamps from a single ballast. Each ballast is rated for a number of lamps and total length of the combined lamps. Fluorescent sign ballasts will typically start at temperatures as low as -20 Fahrenheit (the same as high output fluorescent ballasts).
Compact Fluorescent Ballasts: Compact fluorescent ballasts (cfl ballasts) are available as either magnetic ballasts or electronic ballasts. Compact fluorescent ballasts (cfl ballasts) that operate 2 pin bulbs are always magnetic, while compact fluorescent ballasts (cfl ballasts) that operate 4 pin bulbs are electronic. Magnetic compact fluorescent ballasts are very specific about what lamps they will operate and at what voltage, while electronic compact fluorescent ballasts often run several configurations of wattages and voltages. Light Bulbs Etc, Inc. carries electronic compact fluorescent ballasts that can operate both one or two lamps, and these compact fluorescent ballasts (cfl ballasts) offer universal input voltage (108-305 volts). Magnetic compact fluorescent ballasts are becoming harder to find, and several manufacturers have greatly diminished their lines. As with all ballasts, electronic compact fluorescent ballasts have become the industry standard.