A ballast is a piece of equipment required to control the starting and operating voltages of electrical gas discharge lights.
|List Options||Option Definition||Unit of Measure|
|Hybrid||A hybrid ballast has a magnetic core-and-coil transformer and an electronic switch for the electrode-heating circuit. Like a magnetic ballast, a hybrid unit operates at line power frequencyÑ60 Hz in North America, for example. These types of ballasts, which are also referred to as Òcathode-disconnect ballastsÓ, disconnect the electrode-heating circuit after they start the lamps.||None|
|Probe start||A probe-start metal halide lamp has three electrodes in the arc tube: a starting probe electrode and two operating electrodes. To start the lamp, a discharge is created across a small gap between the starting probe electrode (also called the starter electrode) and the operating electrode. Electrons then jump across the arc tube to the other operating electrode to help start the lamp. Once the lamp is started, a bi-metal switch removes the starting probe electrode from the circuit.||None|
|Programmed start||A programmed start ballast applies power to the filaments first, it allows the cathodes to preheat and then applies voltage to the lamps to strike an arc.||None|
|Pulse start||A pulse-start metal halide lamp does not have the starting probe electrode (Figure 2). Instead it has a high-voltage igniter that works with the ballast to start the lamp using a series of high-voltage pulses.||None|
|Rapid start||A rapid start ballast applies voltage and heats the cathodes simultaneously. It provides superior lamp life and more cycle life, but uses slightly more energy as the cathodes in each end of the lamp continue to consume heating power as the lamp operates. A dimming circuit can be used with a dimming ballast, which maintains the heating current while allowing lamp current to be controlled.||None|
|Electronic||An electronic control uses solid state electronic circuitry to provide the proper starting and operating electrical conditions to power equipment.||None|
|Instant start||An instant start ballast does not preheat the electrodes, instead using a relatively high voltage (~600 V) to initiate the discharge arc. It is the most energy efficient type, but yields the fewest lamp-start cycles, as material is blasted from the surface of the cold electrodes each time the lamp is turned on. Instant-start ballasts are best suited to applications with long duty cycles, where the lamps are not frequently turned on and off.||None|
|Integrated||An integrated ballast is a built-in component of the lamp.||None|
|Electromagnetic||Electromagnetic, core and coil, or simply magnetic, ballast control is very common in line-frequency ballasts to provide the proper starting and operating electrical condition to power a fluorescent lamp, neon lamp, or high intensity discharge (HID) lamp.||None|
|F can||F-Can ballasts are contained within an insulated cans to reduce noise.||None|
|Not applicable||Not applicable||None|
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