A ballast in a fluorescent lamp does two things: it steps up the voltage to drive the lamp, and it provides a "load" or operating resistance when the lamp "fires" and conducts. In a fluorescent application, the correct voltage for the lamp should be used, and the ballast supplies this by stepping up the line voltage. The ballast must also help with current limiting. When the gas in the fluorescent lamp ionizes and conducts, it basically forms a "short circuit" because the ionized gas presents a low resistance to the voltage source. But when the operationg current is routed through the ballast, the ballast is just basically stepping up the voltage until the lamp fires, and then when all the current tries to flow through the lamp, the windings in the ballast say, "Whoa, there, partner." This limits current. Remember that during both the positive and negative cycle of the sine wave that is driving the lamp, the lamp fires and the light comes on. For every cycle of line voltage, there are two "blinks" of the lamp.
No. The principle of incandescent lighting is that a current flows through a filament resulting in extreme heating of the filament and consequently light being emitted from the super heated filament. As the filament heats up, its electrical resistance increases and it does not need a ballast to limit the current.
A cold filament, as when a bulb is first turned on, has the lowest resistance and has the most current going through it. That is when a filament is most likely to burn out and when an incandescent bulb is most likely to fail.
Other Answer
Lighting requiring ballasts are commonly fluorescent and HID lighting. The purpose of the ballast is to provide a spike of current to trigger a chemical reaction in substances such as neon and such.
A small amount of Mercury vapor inside the tube supports an electrical arc which emits UV light. The chemical coating on the inside of the tube transforms the UV light to visible light.
The ballast is responsible for regulating the voltage and current in the electrical arc through the mercury vapor so that the bulb starts, maintains constant light, and does not damage itself or nearby objects.
Answer 2:
The entire theory of how florescent lights work is beyond the scope of this forum, but here's an overview.
Florescent bulbs have a small amount of mercury in vapor form in an inert gas such as argon all contained in a glass tube/bulb. This mercury vapor is heated to start the flow of electric current through it which causes the vapor to glow. But the current would run out of control if not regulated. The ballast regulates this current flow this flow of current to keep the current and amount of light constant. The mercury vapor is a quite efficient emitter of light but it is outside of our visual range (ultraviolet light), so the inside of the tube/bulb is coated with a powder that glows with visible light when the ultraviolet light strikes it. This glowing is called fluorescing thus the name florescent light.
Florescent light-bulbs CFL Compact Fluorescent Lamp
The sun, arc welding, "black lights" (looking fro fluorescence). [inside florescent lights - but its blocked by the surface of the bulbs.)
Check the package, it will tell you if it can be used for these bulbs. Be careful of compact florescent.
The lighting fixture may have 1 ballast, or 2 ballasts. If it has only 1 ballast all 4 lamps must be good in order for it to work properly. It is recommended to replace all lamps at the same time, rather than just the one that is bad. Testing has shown that replacing just one, will shorten the life of the others controlled by that ballast. If 2 ballasts are used, each one is wired to 2 lamps. So, if one pair has a problem the other 2 will still work. To find out how many ballasts you have you must open the fixture. You can't miss them they are the big black rectangular objects.
All dimmer switches hum. The older they get, the louder the hum. If you have compact florescent bulbs in the fixture, this will cause the switch to hum louder.
Florescent Bulbs are full of gases that create light when electricity is put threw them.
no
Dimmers do not work well with florescent lights. The should only be used with incandescent bulbs.
The quick way if the bulb is flickering or out, replace if still flickering or out you need a new ballast!
blackbody radiation
yes
Florescent bulbs are environmental-friendly. Yellow bulbs use more electricity, but their lighting is generally better. Most florescent bulbs take at least a full minute to reach their full lighting, therefore conserving energy when you don't need full lighting. Florescent bulbs are environmental-friendly. Yellow bulbs use more electricity, but their lighting is generally better. Most florescent bulbs take at least a full minute to reach their full lighting, therefore conserving energy when you don't need full lighting.
It is used to fill incandescent lightbulbs, florescent lightbulbs, and bulbs used for photography (flash bulbs)
In incandescent bulbs, gases (other than oxygen) prolong the life of the filament. In florescent bulbs, the gas takes the place of the filament.
No they are controlled by an electronic ballast. It's t12 and magnetic ballasts that are phased out
Florescent light-bulbs CFL Compact Fluorescent Lamp
Krypton is used with Argon as a low pressure filling gas for florescent lighting.