I double the Melanies post.
But if you insist on doing it, PLEASE promiss to have a camera on and with direct link to internet, so we can all see what happens the moment you turn the power ON!
Direct link is needed as you may not be able to send the video file later!
Anyway, some notes on he LED.
1. 50mA is the Absolute Maximum. So according o D.S., 30mA is the working conditions.
2. Each LED is different so a range of 3-4 volts is logiacal. BUT, if you have a source of 10 volts, then you calculate the 3.5 Volts/.03A to find the resistor that each led should have in order to balance its current.
3. A slight increase in Voltage will dramatically increase the current through LED as its characteristics are not Linear. It is NOT a resistor! It is a diode.
Now if you still want to do it, I would suggest:
WARNING All voltages are lethal!
1. Have a 4x1N4004 or 4007 diodes as a rectifier, or even better a bridge rectifier (4 pins) for 500Volts/2-5Amps.
2. On the AC line, fuse and a small resistor for the in-rush currents, say 2-5 ohms.
3. After rectification a capacitor of 220uF/500 Volts.
4. Calculate maximum voltage as 250 Vac x 1,41=353 Volts DC on te capacitor.
5. Calculate the total drop of LEDs say 332.5 Volts. Calculate the number of LEDs 332.5/3,5= 95 LEDs.
6. Calculate the resistor to be in series as (353 - 332.5)/.03 = 680 Ohms
7. Calculate the power of the resistor .03 x .03 x 680= 620mW. I would go x4 to set it at 2,5Watts
OK. We finished.
Hope you wear safety glasses and gloves because:
1. LEDS may explode if they get high voltage by accident
2 Every where on the circuit are very lethal voltages!
If you still want to do it, don't forget the Video Camera!
Ioannis
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