pmostafa
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I have connected 4 White LEDs with 240ac main through 1K resistor in series. The brightness of the output is not satisfactory. What can i resolve this issue?
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Bright light from white light connected 240ac through 1k
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In what way is the brightness "unsatisfactory"?
How bright do you need?
Have you tried using more LEDs?
Have you tried wiring them in parallel?
How bright do you need?
Have you tried using more LEDs?
Have you tried wiring them in parallel?
Jeff Rosenbury
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Or lowering the resistance?
Diodes are often rated for their DC current. Often this is because the junction overheats if over driven. So if the LEDs are pulsed you might be able to go a little over their DC rating since temperatures are based on continuous current draw.
If that's not enough, use a diode rectifier and a capacitor to make your current DC. I doubt the power needs to be too clean, so nothing fancy.
Diodes are often rated for their DC current. Often this is because the junction overheats if over driven. So if the LEDs are pulsed you might be able to go a little over their DC rating since temperatures are based on continuous current draw.
If that's not enough, use a diode rectifier and a capacitor to make your current DC. I doubt the power needs to be too clean, so nothing fancy.
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What is the white LED you are using?pmostafa said:I have connected 4 White LEDs with 240ac main through 1K resistor in series.
240VAC with 1k in series will give a forward current of 240mA, then the reverse voltage will destroy the diodes.
The 1k resistor will need to be rated at 60 watt.
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Baluncore picked up on the fact something seem very wrong in your description.
What you describe should have already gone up in smoke.
Can you assure us somehow that you experiment is not about to hurt you or some tiny fingers in your household ?
What you describe should have already gone up in smoke.
Can you assure us somehow that you experiment is not about to hurt you or some tiny fingers in your household ?
Jeff Rosenbury
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Since he got some light out of the diodes, I assumed he used appropriate parts.
Working with 240V is dangerous. Don't do it unless you are a licensed professional.
If the parts were chosen properly, the circuit should work. If they weren't, out comes the magic smoke. (At 240V this could be dangerous in so many ways.)
Working with 240V is dangerous. Don't do it unless you are a licensed professional.
If the parts were chosen properly, the circuit should work. If they weren't, out comes the magic smoke. (At 240V this could be dangerous in so many ways.)