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Reverse breakdown voltage

  1. May 25, 2015 #1
    I want to power a led off mains, heres my thinking on it:

    resistor-->led-->1n4009 to protect against reverse breakdown voltage, is there anything I'm missing and will it be reliable?
     
  2. jcsd
  3. May 25, 2015 #2

    davenn

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    Gold Member

    Im a bit unsure if I should be giving you circuit advice for mains powered projects
    as I don't really know if you have the experience dealing with potentially lethal voltages

    The way you described above isn't correct
    You also haven't stated what mains voltage you have at your location or what type of LEDs you want to use

    This gives me even less confidence in your knowledge level

    The circuit I will give and strongly advise you follow and with skilled supervision is this one .....

    220V-leds.jpg


    Dave
     
  4. May 25, 2015 #3
    it's just 120 v ac, I don't see why I need a bridge rectifier and cap when all I want to is current and voltage limit a 1.2v led and use a 1n4009 to protect the led against reverse piv? maybe I'm not using the right terminology but I'm comfortable working around mains, I'm pretty sure I won't die. would you have questioned me if I had used a neon bulb and a resistor? basicly it's a half wave rectifier and I'm just adding a voltage drop and current limiting. if I used a varic and fast blo fuse, high wattage resistor I would test this out myself before asking, just wondering.
     
    Last edited: May 25, 2015
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