How to make your own LED bulbs.

[claude]

Bruce, I'm glad I helped you. I also thought about using phone plugs. And I will, it's the only way it can be done without additional headaches. I plan to make a desklamp and I will add it here once it's finished. So stay tuned.

Regards,

Claude

[claude]

As I promised, I'll post future applications of the LED bulbs I make. Here's a headlamp.

The bulb here is a 6V one, it takes 170mA from the battery. The body of the headlamp is a old mobile phone charger base I drilled so that the bulb base would fit in and then I glued it inside with bicomponent glue. The wire is a mose wire, very flexible. It has 1.4m length and the power connectors at the end are for connecting the headlamp to a small SLA 6V battery I'll carry in my pocket. I decided the biggest battery I could carry in my pocket is a 4Ah one, so that should give me plenty of hours. The small one is a 1,3Ah so it's nothing spectacular.

Claude

[coldspot]

Claude- or Ghurd-

Claude

super nice post and write up !!!!!!!!!!

My question-

"they generate virtually no heat"

Is that true?

LEDS don't heat up at all?

I've been looking around a bit for that info,

I'm trying to make some small amounts of heat with small amounts of power and was wondering about LEDs or maybe little old type light bulbs. Around the 3 V range.

 I know, Ni-Chrome wire works well but I was wanting to try something a bit different and modern like LEDs maybe.

[ghurd]

They don't heat much if operated properly.

Say 3.2V x 0.020A = 0.064W, or 0.22BTU at the most.

G-

[la7qz]

Hi

Cruising sailors (like me) have been living off grid for a long time and LED lamps are getting quite popular in the boating industry.

I find that most commercially made LED bulbs are very expensive and fail quite quickly on a yacht. The ones I've seen all had the LEDs in strings of three, and they would often flicker for a while before failing. Usually one string at a time until the whole array was dead. I had the exact same problem with a couple of arrays I built myself using three LEDs and a resistor in each string. Sorry, the boat is at the bottom of the Atlantic, and I don't remember the value of the resistors.

The reason is probably that the voltage on a yacht can fluctuate a lot. Anything from 11.5V at night if the batteries are undercharged to 14.4V (14.2 in the tropics) when the engine is running with a high output alternator.

My suggestion would be to calculate the resistors for 9 or 10V and use a 7809 or 7810. Possibly with the LED's in strings of two. The voltage regulator IC's are dirt cheap. Certainly cheaper than an array of burnt out LED's.

Owen Morgan

Yacht Magic

Admirality Bay, Bequia

A photo of my boat can be found here:

http://www.panoramio.com/photo/737793

Click here for my latest reported position:

http://www.findu.com/cgi-bin/winlink.cgi?call=LA7QZ

[imarzouka]

Here is another LED resistor calculator that I use

http://ledcalculator.net

[oquedo]

Hello, im a newb here..

Could you use a computer power supply to feed this LED bulb?

If so how would you make the conector?

Ive got no electric or electronic background but Im interested in this specific proyect, so sorry in advance.

[hesh]

Hey, GREAT tutorial!

I am trying to create bulbs just like this, but I need to be able to connect them directly to 120vac, without using a transformer.  I am looking to connect them to a dimmer pack that I have so I can control the brightness.  Any ideas on how this could be done?

Thanks.

[claude]

You could use that computer power supply to power this bulb, no problem there as the voltage is well regulated. You just need to find the proper resistors for a LED current of 18ma (longer life, lower brightness) or 20mA (shorter life, increased brightness). Just use the 12V connectors (the ones that feed the HDD and CD/DVD drives. Choose the wires (as there are 4 of them in each connector) to have 12Vcc on a pair (usually red and black.

That source could power up a lot of LED bulbs. A little overkill if you ask me. A smaller wall transformer would take way less space and be just as good.

[claude]

There are only a few ways to connect this bulb to 120Vac. None of them are efficient unless you use a switching power supply. I gave up my plans to make a 120V/220V LED bulb as the risks&losses are too high. One idea would be to use one really small 12Vcc transformer and hide it inside a burnt CCFL bulb base along with this bulb. This way you would have a 120V/220V LED bulb.

A standard dimmer CAN NOT be used on LEDs. You need to make you own PWM dimmer for that. Here's one of my favourites.

http://www.uoguelph.ca/~antoon/circ/pwm555.html

I tried it and it works fine. The parts are very easy to find and you could replace the MOSFET with any N-channel one. There is one catch though. You will only be able to dim the bulb from ~5% - 95% as there are diodes losses involved. Schottky diodes might give you more range. But you'll never get 0-100% power with this one.

[malkari]

hi all im new , well i think you are all very clever at this stuff .I was wondering how much a 6v led version cost to build inc parts. i prob have to pay someone to help me build because i have fribromyalgia,and it looks fiddly lol.i have a 6v 10ah sealed lead acid so that should be ok as im hopin to use a good led light for my bike as my best means of transport as i cant walk far even biking is a task.At the moment ive got the battery wired for my old dynamo lights ,and was lookin through many sites etc about leds lights and some places charge the earth.

[zeusmorg]

  Strings of two 3.3v 20 Mah would require a 22 ohm 1/4 w resistor in parallel. This would give you a 7 v setup which on that 10 Ah/r battery would be fine. If you design for 6 v. then you end up with a single LED and 150 ohm 1/4 w resistor per string.

 If you're still using a dyno for charging while riding designing for 7 v. would be more practical and require fewer parts.

 Actually a halogen light will probably be a lot more practical for a headlight to see by, even though the power requirements are higher.

 As to how many you use, it depends on the brightness you wish to achieve.

You may wish to look at some of the links posted earlier in this thread.

[malkari]

 PWN4 K2 Luxeon Star Neutral White 130 Lumens , what driver ? resistor i need for this pls.i gather i can get  a 6v one from a led place.tyvm

[mmmmna]

quote: "Just use the 12V connectors (the ones that feed the HDD and CD/DVD drives. Choose the wires (as there are 4 of them in each connector) to have 12Vcc on a pair (usually red and black."

claude: FWIW, you've only mentioned using the 12V output (which are YELLOW and BLACK, not RED and BLACK), when every other output of a PC supply COULD be used. Essentially each power supply output needs a different resistor value. But wait before you jump all over this! There are some issues that need to be discussed.

Common PC power supplies offer +5@20 to 45+ Amps, but the 12V outputs are usually limited to only 5 to maybe 14 amps (barely 100 Watts). Just using only the 12V output is not really taking full advantage of the 300+ Watts which almost any PC power supply could be used for.

    ->Think about that: at 4 watts per LED lamp, a 340 Watt PC power supply could power maybe 80 lamps - enough lamps for a whole house, certainly support for a lot of lamps per room! Let me add that running long wires to illuminate a house is not a good idea, here.

There is a possibility for using the 3.3V outputs, but I'd suggest not getting into a discussion about using 3.3V since 3.3V USUALLY draws from the 5V supply, and that gets very difficult to explain.

Don't forget that oftentimes in PC power supplies, there are additional outputs of +5V, +12V, -12V; but again, like the 3.3V output, I'd suggest users should stay away from outputs labeled '5VSB' as that output is usually too limited for more than a few lamps.

In my experience, the negative output voltages tend to be a bit sloppier compared to the positive voltages.

Normally, a PC power supply needs some minimum amount of power to be drawn from a particular output in order to get accurate voltages on all the other other outputs. users might want to plan on using the specified output as the output which has the first LED string.

Don't forget that PC power supplies expect to be in a room where humans would reside - putting a PC power supply in an attic is not a great idea because in the summer, almost any attic I can think of would get very hot and possibly cause the power supply to either fault or fail completely.

Lastly, ATX class PC power supplies need to be enabled properly or they will not turn on. Connect the green wire which is in the motherboard power connector (the connector which has something like 16 wires) to a black wire in the same connector, and it all starts running.

Be careful, but have fun!

[ghurd]

Consider this a Public Service Announcement.

Public Service Announcement        Public Service Announcement        Public Service Announcement        Public Service Announcement

I see people reading this at almost any given time.
There are 7 people reading it at this time.

This post is currently 3 and a Half Years Old!

Things change.
The basic concepts are the same.
Do Not consider this as new or current information.

[wooferhound]

Here is how to make LED lights in the FAQs section . . .
Many different methods discussed
http://fieldlines.com/board/index.php/topic,143569.0.html

[claude]

Thanks Glen for your help. 

Is it three years and a half already?? Man, time really flies... I remember like yestereday soldering those LEDs with tears in my eyes as the superglue smoke reached me. I need to stress that again, people, don't solder LED pins that have superglue on them! You'll tearfully regret it. For half an hour or so.

This post is also available on instructables.com (http://www.instructables.com/id/How-to-make-your-own-LED-lightbulbs/)
and it had 90.362 views so far. I'm not bragging. Really. I just wanted to make it more available. All sort ot people commented on it. Some even asked if I can mass produce it.

All I did was actually was to find a way to fit LEDs inside that bulb. That's not a big deal. Nothing else is new. And I'm not that skilled at all, people should do the same thing I do when I need to know more. Google. And break things.

[Hirocaster]

the most powerful one I made takes 12V@200mA and has 6 pcs. of 0,5W LED's. These LEDs were pretty expensive but the light output is great.

Can you give me more details about these leds? Specs or datasheet? Thanks!

Hiro.

[Bruce S]

the most powerful one I made takes 12V@200mA and has 6 pcs. of 0,5W LED's. These LEDs were pretty expensive but the light output is great.

Can you give me more details about these leds? Specs or datasheet? Thanks!

Hiro.

As said this is a very old post. It remains a very good tutorial. So please read then entire tutorial then come back with questions. ALL the info you require is in this post.

This will surely help you a ton.

Cheers
Bruce S

[Vojta7]

It looks like you used some CAD to arrange those LEDs. What program do you recommend for doing this?