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Disco Light lamp power

  1. Oct 18, 2011 #1
    hi guys

    Am a little week in physics.. so here is the situation:

    I have a disco light that uses a 12v 50w bulb to operate.. however it is too weak.

    Since at home i can change a 240v 50 w bulb to a 240v 100 w one... am just wondering if it is possible to change the 12v 50w to a 12v 100w.

    is it safe and can it be done?

    Thank you...:biggrin:
     
  2. jcsd
  3. Oct 18, 2011 #2

    Bobbywhy

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    Yes, you could change from a 12 V 50 W lamp to 12V 100W lamp.
    1. You would have to find that lamp and buy it.
    2. Your new lamp will draw approx. two times the electrical power. Is your 12 V supply able to deliver 100 Watts?
    3. Will the existing wiring and lamp socket carry the increased current? Use Ohm's Law to find the current.
    4. If yes to all the above, the new lamp will generate a lot more heat. Will the fixture holding the lamp or nearby material melt?
     
  4. Oct 18, 2011 #3
    You could try to find a fluorescent or LED light that will produce more light with less energy. Incandescent bulbs are about 1% efficient, fluorescent bulbs are about 10% efficient. LEDs are about 90% efficient.

    Switching from a 50 watt incandescent light to a 10 watt fluorescent light will give you more light without overtaxing your 50 watt electrical supply or heat-damaging near by materials. In essence you solve problems 2, 3, and 4 stated above while possibly exacerbating 1.
     
  5. Oct 18, 2011 #4

    Bobbywhy

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    A flourescent lamp will not operate on the existing 12 V power supply. Nor will LEDs.
     
  6. Oct 18, 2011 #5

    DaveC426913

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    Please note that most small devices are only rated for the bulb that they are meant to take. Often light fixtures urge that you use no more than a 60W or even 40W bulb in them.

    Putting a 100W bulb in a disco ball that is meant to take a 50W bulb is a bad idea.

    At best, it will overheat and melt the ball.
    At worst, you might have an electrical fire on your hands. Or ceiling.
     
  7. Oct 18, 2011 #6

    rcgldr

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    An automotive LED headlight would operate at 12 volts, but I don't know the power requirements for these. It would be directional. These are also expensive. You didn't mention what the light would be used for. If this is some type of music light that changes brightness, the LED headlight wouldn't work.
     
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