There have been many theoretical schematics for LED on mains.
Now, just do one thing
Connect one LED and a series resistor of 120 KOhms or higher and connect it to mains, 240 volts.
What will happen?
Yes, I know. The LED will blow.
But does it really happen?
No. It does not blow and keeps illuminating challenging the theory.
Go try and check for yourself.
Gajanan Phadte
Now, just do one thing
Connect one LED and a series resistor of 120 KOhms or higher and connect it to mains, 240 volts.
What will happen?
Yes, I know. The LED will blow.
But does it really happen?
No. It does not blow and keeps illuminating challenging the theory.
Go try and check for yourself.
Gajanan Phadte
Clearly you've tried it and you are blowing LED's. The LED is breaking down when it is reverse biased by the mains voltage. LED's do not like being reverse biased. You need to put an 'anti parallel' diode across the LED, or use a full wave bridge rectifier better still.
2nd point. Dont go dicking around with mains voltages unless you know what you are doing.
2nd point. Dont go dicking around with mains voltages unless you know what you are doing.
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Bonsai, I have worked for nearly 3 decades and many a times our instruments have high voltage 4 KVDC, and high current that can give an energy of 8KJ.
I think u have not read what I have written.
An LED in series with one 120KOhms is fitted in our EVERY 3 pin mains socket and the damn thing works for so MANY YEARS.
BELIEVE IT OR TRY IT.
Gajanan Phadte
EDIT: Yesterday, I connected an LED in series with 240 Kohms across a incandescent lamp switch to locate the switch in dark. It was on whole night and still going strong.
Do not reply without trying. Try it if u r a pro.
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few possibilities, among which that they are leds with 2 antiparallel chips inside, or that the LED can sustain the reverse current.
did you mount them and know what leds they are, or factory mounted?
can you measure what configuration is inside the led body?
did you mount them and know what leds they are, or factory mounted?
can you measure what configuration is inside the led body?
The one in the socket is just ordinary old type, non high brightness. The one I connected is high brightness. When I went home for lunch, it was still glowing.
I suspect it has something to do with the capacitance and the reverse current combo. I at work presently do not have even an oscilloscope, otherwise, would have checked the waveform after connecting it to an isolation transformer.
Believe me, I know this works since 6 years back and somehow didn't write it here, due to .... Reply like in post #2 was very much anticipated.
Gajanan Phadte
I suspect it has something to do with the capacitance and the reverse current combo. I at work presently do not have even an oscilloscope, otherwise, would have checked the waveform after connecting it to an isolation transformer.
Believe me, I know this works since 6 years back and somehow didn't write it here, due to .... Reply like in post #2 was very much anticipated.
Gajanan Phadte
... that is a Neon Lamp, not an LED.
... you're very lucky. That LED should have failed.
I will guess that the LED went into reverse breakdown, but the 240k resistor limited the current to a value that was small enough that the silicon didn't fry.
Your experiment doesn't invalidate the theory. Bonsai is right.
Bonsai,
I respect your sentiments but is it that dangerous that u cannot try.
I will supply u one safe method (LOL) of switching a series diode IN and OUT, if u don't know how to.
Be a Man. Go try and laugh-out-loud till u find out.
And u can write it up for our benefit. I know U can find out.
Gajanan Phadte
I respect your sentiments but is it that dangerous that u cannot try.
I will supply u one safe method (LOL) of switching a series diode IN and OUT, if u don't know how to.
Be a Man. Go try and laugh-out-loud till u find out.
And u can write it up for our benefit. I know U can find out.
Gajanan Phadte
Hi ,
sure it will work! In mains voltage (alternating current) it has 50Hz frequncy that meen 50 positive cycle 50 negative cycle. when LED connected with resistor to limit the current it will conduct in a positve cycles as forward bias and glow during negative half cycle it will not glow;but no one can recognize this with naked eyes because it happens 50 times per second😀 quite fast to recognize.
i am doing this for 20 years for all the amplifier main piolt lamps
hope its explained.
sure it will work! In mains voltage (alternating current) it has 50Hz frequncy that meen 50 positive cycle 50 negative cycle. when LED connected with resistor to limit the current it will conduct in a positve cycles as forward bias and glow during negative half cycle it will not glow;but no one can recognize this with naked eyes because it happens 50 times per second😀 quite fast to recognize.
i am doing this for 20 years for all the amplifier main piolt lamps
hope its explained.
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I shall send all of u an LED and a series resistor, if u can't find the two.
Any more theoreticians who don't want to risk of blowing this neutron-atom combo.
Gajanan Phadte
Any more theoreticians who don't want to risk of blowing this neutron-atom combo.
Gajanan Phadte
all the LEDs availabel in the market except chip mounted flasing,bi or tri clour LEDs
all simple LEDS
vijay
all simple LEDS
vijay
Why don't you connect two LEDs in series, in reverse ? If they both light up, that will prove that the LED is in reverse breakdown.
Anyway, I don't understand what you are trying to prove. What you are doing is definitely unsafe and unwise. Just because you did it and got away with it doesn't mean everyone should start doing it.
PJP,
Do u live in India?
Yes, then go buy one CPL/Anchor brand switch socket with LED indicator, open it and see for yourself.
Buy the one with the round red LED seen from outside.
NO, IT WORKS AND I KNOW IT WORKS SINCE 6 YEARS
Do u live in India?
Yes, then go buy one CPL/Anchor brand switch socket with LED indicator, open it and see for yourself.
Buy the one with the round red LED seen from outside.
NO, IT WORKS AND I KNOW IT WORKS SINCE 6 YEARS
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You've been doing it wrong for 6 years.
p.s. I do have a few Anchor brand sockets, and they have Neon Lamps in them, not LEDs. (They are quite old ~15 years, so maybe the new ones have LEDs in them, in which case, Anchor is doing it wrong too.)
Hi pjp,
whats wrong? 😕what wrong in theory connecting LED with resistor in mains?
resistor work is to limit the current inrush or more current to fry the semiconductor. As i posted earlier it will work only in positive half cycle as forward bias like simillar to DC voltage.
unless you touch the LED leads or ground it to chasis nothing danger🙄 there is nothing to do with photon or neutron. we just playing with electorns (limiting with resistor-ohms law).😀
vijay
whats wrong? 😕what wrong in theory connecting LED with resistor in mains?
resistor work is to limit the current inrush or more current to fry the semiconductor. As i posted earlier it will work only in positive half cycle as forward bias like simillar to DC voltage.
unless you touch the LED leads or ground it to chasis nothing danger🙄 there is nothing to do with photon or neutron. we just playing with electorns (limiting with resistor-ohms law).😀
vijay
Vijay,
Unless an LED manufacturer says it is safe to have ~1mA of reverse current (240k resistor @ 240V) flowing through an LED on a long term basis, how can you make such an assumption ?
Unless an LED manufacturer says it is safe to have ~1mA of reverse current (240k resistor @ 240V) flowing through an LED on a long term basis, how can you make such an assumption ?
Here is the neutron atom combo that will blow the theory. LOL
The bright orange glow at the background is of the neon and I masked it so that the dim lighted Yellow LED can be seen.
Gajanan Phadte
EDIT😀on't point out that the resistor is 150K and not 120K. This is the first resistor and the first LED that I found on in the junk around my workplace.
The bright orange glow at the background is of the neon and I masked it so that the dim lighted Yellow LED can be seen.
Gajanan Phadte
EDIT😀on't point out that the resistor is 150K and not 120K. This is the first resistor and the first LED that I found on in the junk around my workplace.
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