can i modify a power supply

Discussion in 'The Projects Forum' started by Arcamax, May 12, 2015.

  1. Arcamax

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    May 5, 2015
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  2. MrChips

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    It is possible but the solution is not so obvious. What are you planning on powering with it at 12VDC?
     
  3. Arcamax

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    May 5, 2015
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    i want to power some 12v white led strip for a project
     
  4. MrChips

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    Find out how much current is required for the LEDs and then build a constant current supply from the 19VDC output for that amount of current.
     
  5. MaxHeadRoom

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    One advantage with P.A. is they will give you a refund if you screw it up, no matter how long ago you bought it.;)
    Max.
     
  6. MrChips

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    I don't know how much current you need but let us suppose you need 2A.
    Then you have to dissipate (19V - 12V) x 2 A = 14W
    A hunking big 3.5Ω 25W resistor will do the job - or a 6V 25W light bulb.
    It would be better to find a 12VDC power supply which should not be too difficult a task.
     
  7. Arcamax

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    May 5, 2015
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    well there is the chart of the leds: i bought 2 quantities of white 1m non-waterproof

    will dc work? Someone told me to use Ac power supply.(i can get some dc adapters at be@electronics where i live, the max current one i can get is 1.6Amps though)
    http://www.be-electronics.com/category_s/2380.htm
    http://www.be-electronics.com/product_p/rpr1201a6p5.htm
     
    Last edited: May 12, 2015
  8. AnalogKid

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  9. Dodgydave

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  10. MrChips

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  11. Arcamax

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    May 5, 2015
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    ok if everyone is looking at the chart i provided, what is the minimum amps i need for the output?
     
  12. Dodgydave

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    the leds vary from 0.4amp to 1.2amps, per strip, so how many strips x what current = adapter rating,

    post#9 adapter...
     
  13. Arcamax

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    May 5, 2015
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    1 1m strip
     
  14. Dodgydave

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  15. Arcamax

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    May 5, 2015
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  16. Dodgydave

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    thats 1.6amps,

    see my post #9, from ebay is $6.99 @ 5amps
     
  17. Arcamax

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    May 5, 2015
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    do i really need it that high though
     
  18. Dodgydave

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    better to get a higher rating psu, it will only give out what you need,also its cheaper
     
  19. Arcamax

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    May 5, 2015
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  20. Arcamax

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    May 5, 2015
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    i cant find a good, cheap 12v power supply on ebay.ca
     
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