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  2. Electrical ballast - Wikipedia

    en.wikipedia.org/wiki/Electrical_ballast

    An electrical ballast is a device placed in series with a load to limit the amount of current in an electrical circuit. A familiar and widely used example is the inductive ballast used in fluorescent lamps to limit the current through the tube, which would otherwise rise to a destructive level due to the negative differential resistance of the ...

  3. List of LED failure modes - Wikipedia

    en.wikipedia.org/wiki/List_of_LED_failure_modes

    Reverse bias: Although the LED is based on a diode junction and is nominally a rectifier, the reverse-breakdown mode for some types can occur at very low voltages and essentially any excess reverse bias can cause immediate degradation, and may lead to vastly accelerated failure. 5 V is a typical maximum reverse bias voltage specification for ...

  4. LED circuit - Wikipedia

    en.wikipedia.org/wiki/LED_circuit

    In CC drivers, the voltage changes while the current stays the same. CC drivers are used when the electrical load of the LED circuit is either unknown or fluctuates, for example, a lighting circuit where a variable number of LED lamp fixtures may be installed. As an LED heats up, its voltage drop decreases (band gap decrease [1]). This can ...

  5. LED lamp - Wikipedia

    en.wikipedia.org/wiki/LED_lamp

    A 230-volt LED filament lamp, with an E27 base. The filaments are visible as the eight yellow vertical lines. An assortment of LED lamps commercially available in 2010: floodlight fixtures (left), reading light (center), household lamps (center right and bottom), and low-power accent light (right) applications An 80W Chips on board (COB) LED module from an industrial light luminaire, thermally ...

  6. Electric light - Wikipedia

    en.wikipedia.org/wiki/Electric_light

    An electric light, lamp, or light bulb is an electrical component that produces light.It is the most common form of artificial lighting.Lamps usually have a base made of ceramic, metal, glass, or plastic which secures the lamp in the socket of a light fixture, which is often called a "lamp" as well.

  7. High-intensity discharge lamp - Wikipedia

    en.wikipedia.org/wiki/High-intensity_discharge_lamp

    However, the bright headlights have given rise to complaints about glare. [10] HID lamps are used in high-performance bicycle headlamps, as well as flashlights and other portable lights, because they produce a great amount of light per unit of power. As the HID lights use less than half the power of an equivalent tungsten-halogen light, a ...

  8. Headlamp - Wikipedia

    en.wikipedia.org/wiki/Headlamp

    The ballast now supplies stable electrical power so the arc will not flicker. Stable operating voltage is 85 volts AC in D1 and D2 systems, 42 volts AC in D3 and D4 systems. The frequency of the square-wave alternating current is typically 400 hertz or higher. Headlight indicator example

  9. Mercury-vapor lamp - Wikipedia

    en.wikipedia.org/wiki/Mercury-vapor_lamp

    Color corrected" mercury bulbs overcome this problem with a phosphor on the inside of the outer bulb that emits at the red wavelengths, offering whiter light and better color rendition. Mercury-vapor lights operate at an internal pressure of around one atmosphere and require special fixtures, as well as an electrical ballast. They also require ...