Can a 1n4009 protect a LED from reverse breakdown voltage when powered by mains?

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SUMMARY

This discussion centers on using a 1N4009 diode to protect an LED from reverse breakdown voltage when powered by 120V AC mains. The original poster proposes a circuit consisting of a resistor, LED, and the 1N4009 diode, questioning the necessity of additional components like a bridge rectifier and capacitor. Expert advice emphasizes the importance of a complete circuit design for safety and reliability, particularly when dealing with high voltages.

PREREQUISITES
  • Understanding of 120V AC mains voltage
  • Knowledge of LED specifications and characteristics
  • Familiarity with diode functions, specifically the 1N4009
  • Basic circuit design principles for high voltage applications
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  • Research the use of bridge rectifiers in AC to DC conversion
  • Learn about LED current limiting techniques
  • Study safety protocols for working with mains voltage circuits
  • Explore the role of capacitors in smoothing rectified voltage
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Electronics enthusiasts, hobbyists working with LED circuits, and anyone designing mains-powered devices requiring voltage protection.

thankz
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I want to power a led off mains, here's my thinking on it:

resistor-->led-->1n4009 to protect against reverse breakdown voltage, is there anything I'm missing and will it be reliable?
 
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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
 
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? basically 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.
 
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