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24VDC to 12VDC using LM317T questions

Discussion in 'Electronic Projects Design/Ideas/Reviews' started by qsiguy, Sep 10, 2007.

  1. ericgibbs

    ericgibbs Well-Known Member Most Helpful Member

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    Hi Sarma.

    As its a 'one off' project I would still use the cheapest option, resistor.

    In the past I have reduced 'excess' voltages by removing a few turns off the transformer secondary,
    thats a 'zero' component cost way of doing it;)
     
  2. mvs sarma

    mvs sarma Well-Known Member

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    Lovely Eric--the Zero component way..
     
  3. qsiguy

    qsiguy Member

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    Loving all the feedback and discussion. This project is experimental but may not be a one off. If I can get it to work efficiently and reliably for a low cost we may integrate this circuit into quite a few of our panels. A majority of our panels utilize 24VDC and these lights are all 12VDC. Some of the simple panels that can run entirely on 12V it's not needed or larger panels where there is ample space we just add a 12V power supply to run them but where space is tight or cost if a factor, adding a 2nd power supply just for the neon light isn't an option.

    Would that 10W resistor need a heat sink of any kind?
     
  4. dave

    Dave New Member

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  5. ericgibbs

    ericgibbs Well-Known Member Most Helpful Member

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    hi,
    The resistor should be mounted so that it get rid of the heat, not tight down onto a pcb, standing clear and away from heat sensitive components.

    Some types have a 'brass' type body, that are designed to bolt to the metal enclosure
     

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