mains operated 25nos. led Lamp

Hi



This is a 25 nos Led  operated from mains of 230v supply. I bought a flourscent lamp adapter from a scrap dealer, because its easy to dismantle (a screw in the middle of the fitting) instead of cutting etc.,.the beautiful thing is, in many homes we find damaged, burnt out CFL, adapters etc., where we actually have no use, hence with few components readily available in the market and a hour on a sunday afternoon, you should be able to put these components together.

Step 1: Circuit diagram

Circuit diagram to that would make your work easier

Comments

[castiganalgas]

Thank you very much, I was looking for something like this, only two questions, drawing on the resistance of 22 ohms at 1 watt and then on the necessary components to 0.5watt says,,,, is the same?

I have a LED, 5mm I 20mA - 30mA, U 3.2-3.35volt
I can use with this circuit?
Thank you very much!

pd English translator of google.

[patrickvaz]

Hi,
Care, caution is required in any work, or accidents do take place, Knowledge of components, soldering, current is a must... Few people I know have put this in place and have been working for the last 18 months or so......... all the best...

[offtherails2010]

Hi there Patrickvax,

I LOVE THIS INSTRUCTABLE !!!

HUGELY !!!

Only because im really fed up of all my LED bulbs FAILING Due to the heat killing the SMD Bridge Rectifier IC Chip in them - I HAVE BOUGHT 5 OF THEM AND THEY HAVE ALL FAILED in about the space of 1 YEAR !!!!

So..... Again.... MANY THANKS !!!

You see, i want to re-design the LED-Placement onto a custom made PCB (using Eagle CAD Soft !) and house it inside my magnifying lamp that i use Every-Other-Day --- if not EVERYDAY, lol, and the 4th LED bulb failed and now im super-angry at the poor LED-Spacing of this bulb because all these LED's (3020 SMD Size) packed tightly in a very small footprint generates so much heat that it eventually fries the Bridge Rectifier IC...

And so i want to mount these SMD LED's all the way around the lamp magnifier so that they are all nicely spaced out and wont collectively generate as much stupid heat that eventually fries the IC...

But... Heres my question... (Finally, your thinking, lol !)

How would i connect this 4-Pin SMD Bridge Rectifier IC up into your schematic:

4-Pin SMD Bridge Rectifier

 Here is a picture of the LED Bulb that fries the IC - everytime i buy a new one (VERY EXPENSIVE for someone living on a shoestring are these bulbs, lol)

i have the 3020 Sized SMD LED's and capacitor, various bits to make my own PCB but just a little help with this IC would be great as i have them on the way and really want to keep as much of this project as possible SMD components, if i can lol !

oh and many thanks in advance & sorry about reading this LONG script, lol ! 

[WEBBY007]

LED LIGHTS WHAT ABOUT WARNINGS WHEN MAKING THIS CIRCUITS
AND ON OUTSIDE OF UNIT . THIS IS NOT A CIRCUIT TO BE MADE BY ANY HANDYMAN . IT IS VERY DANGEROUS

[viswamtvs]

i have this circuit in already
but
your post easly steps
thank u

[pfred2]

At the bottom of this article is an easier way to light LEDs with wall current:

http://www.evilmadscientist.com/article.php/hotdogs

[Dr.Bill]

I had a hotdog cooker that was fully enclosed. The hot dogs were stuck on the nails in the ends and the lid closed. When the lid closed the juice turned on and the dogs cooked. I never trusted it enough to plug in the dogs while it was pluged in the wall.

[snotty]

Nice project!

A couple of questions: why didn't you use a capacitor to prevent the light from flickering? That's assuming it does flicker.
And isn't this level of DC current more dangerous than AC current? I thought I headed that but maybe it's just a rumour.

[nanosec12]

Your question "And isn't this level of DC current more dangerous than AC current?"

The real answer is that yes it is more dangerous, but to fully answer it's not the level of current that makes it more dangerous, it's the voltage. The higher voltage is more dangerous than the 120v that is used in the United States, but as a point of fact either is enough to KILL YOU if handled improperly.

Take the right precautions, and even extremely high voltages can be used safely, but you have to put safety first.

[snotty]

Hmm.

Are you sure it's a question of voltage? I'm pretty sure it's amperage that harms humans. That said, someone was playing with a flyback transformer from a TV that put out something like 120v DC and someone said 120v DC is much more dangerous than 120v AC all other things being equal.

Know what I mean?

[nanosec12]

Your are correct, but my comments above still stand. It is the current that harms you, BUT it is not the current that flows through the circuit that harms you it is the current that flows through your body when grounded that harms you.

You could easily, and probably have, put your hands on an insulated connector that is carrying 10 amps ( like unplugging a vacuum while it is running) and feel no pain, even though the current in that circuit is at least 10x what it would take to kill you. But that is the circuits current, and needs to be figured out for fuses and circuit breakers and such, but not the current you would feel if you touched an exposed conductor.

If you use Kirkhoff's rule ( V = I*R transposed to I = R/V) you can show that the only adjustable variable in the equation is the Voltage. Your bodies resistance will vary over time but not over a large range, and the current values that will hurt/kill you are also known. This leaves the voltage as the variable of concern.

That is the reasoning behind my post of the voltage being the concern, vice the current.
As to your second question about AC vs. DC it is a matter of physiological properties. With an AC current the muscles in your body will contract and release with the changing voltage, with a DC circuit they will only contract. Because of this, depending on how you contact the circuit, if you were to 'grab' the conductor with a closed hand the DC would prevent you from letting go, whereas the AC would give you some opportunity to let go.

Hope this helps.

[pantaz]

Physiological effects of electricity"It is the current that harms you, BUT it is not the current that flows through the circuit that harms you it is the current that flows through your body when grounded that harms you."

That is dangerously wrong!

You don't need to be grounded -- less than one amp passing through your heart (such as from one hand to the other) can cause potentially fatal cardiac fibrillation. Your heart doesn't care if it's AC or DC. 

As for comparative danger of DC versus AC, you might want to look at how electric chairs function. Also, muscle fibers do not react fast enough to "release" on the zero crossing of standard 50 or 60 Hz power line.

A good overview is, "Physiological effects of electricity" 

[Jodex]

Think of a static electricity shock. You've propably got one some day, aren't you? There the voltage is thousands of volts, sometimes even millions of volts. And that doesn't kill you, because there are just some microamperes, and it ain't much.

[kikiclint]

Truly it is the amount of current that goes through your heart that is the real killer. Higher voltage just helps push the current through. Just put a fuse rated for a little more than your lights need and you should be safer.

[wobbler]

A fuse will do little if anything to protect a person. The amount of current needed to give a lethal shock across the heart is only 100mA and I doubt you could set a fuse correctly, assuming it actually reacted quickly enough in the first place. A fuse only really protects the wiring or a dodgy connection in a device.

I always use a Residual Current Circuit Breaker in my house to give some protection, but even these will only work where the short through the person is effectively from the live to ground, not where the person is shorting live to neutral. However, it's far more likely that someone getting a shock will be touching something earthed and then get hold of live or a faulty made-live device. They trip in about 25mS with a fault current of 10mA, much less than a potential killing voltage and probably not even felt.

[meerut260]

I want to build a Birthday LED sign with 250 LEDs in it. Could you please provide a circuit diagram to be operated with 110vac Thanks

[patrickvaz]

hi Meerut 260,

I have a circuit for Happy new year, you just need to re-arrange the leds for birthday sign.

send me you e-mail id, will send it across to you

[patrickvaz]

Hi Meerut260,

A similar circuit attached, you can modify to your requirements.
http://www.instructables.com/id/LED-TUBE-LGHT-AC/#step1

I was out in Africa (ethiopia), will get back with any queries.

[rohitkumar3333]

Voltage/current/ac voltage dc voltage everything is dangerous, if proper precautions are not adhered to, the question i see is the resistors can be compensated with a capacitor.

this is a instructable, are ideas that people do come up with,we can add fuse, fusible resistor, d.c capacitor, surge resistor, but question is, is there place available in that enclosure.

[sudharma]

Voltage and current are interrelated. To have current you need voltage. The higher the Voltage, the higher the current. That's why low voltage cannot kill you.

Using resistors to drop the voltage is wasting energy as heat. By using Capacitors there is no heating and the energy consumption is only by the Leds + the nominal circuit losses.

DC voltage is more dangerous because the current flow is continuous unlike the AC voltage. The current through the body makes the muscles contract. For example, If a live high voltage wire is touched by the fingers, the finger muscles contract around the wire and its practically impossible to pry them open.

Whereas with AC it may be possible to open the fingers.(when the voltage reaches "0" ( Sin wave).

[Factus]

Cool!

Questions:
1) If there were no resistors would there be just 230v DC due to the diodes? So all the resistors are doing is dropping the voltage to something more workable?

2) Does this not mean there is ALOT of wasted current being pushed out by those resistors? Something like a 100v drop?

[DELETED_thpritam]

(removed by author or community request)

[wobbler]

It says 230v on the circuit diagram. It won't matter if it's 50 or 60Hz, as it's rectified it will make no difference. As an aside, you could replace some of the resistors with a suitable capacitor to act as an ac impedance in a standard RC mains dropper configuration. This would mean less energy wasted as heat in the resistors, but the values used would then depend on the frequency of the mains. The circuit is used here http://www.instructables.com/id/Power-light-for-Glue-Gun/step4/The-circuit/ but it would obviously need different values when driving a string of leds.