Author Topic: How to make your own LED bulbs.  (Read 256631 times)

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claude

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How to make your own LED bulbs.
« on: January 28, 2007, 09:52:43 PM »



After many attempts to make all sorts of LED-conversions I finnaly found one solution that is simple and efficient. Of course, you do need a great amount of patience in making this but when you consider the countless hours of pure light -low consumption you'll get, it's all worth it. This tutorial is about converting regular GU4(MR11) halogen bulbs to LED bulbs while maintaining full usability as 12V light bulbs that can be used in indoor task or accent lighting.





You'll need the following stuff to start working:



  • one halogen bulb (burnt or new since they are really cheap) with no glass cover on front.
  • LED's - as many as you want. You may want to keep this number reasonable since more than 22 LED's will make you work painful.
  • online acces to http://led.linear1.org/led.wiz , a great LED array calculator you can use to figure out the resistors you'll need depending on your number of LED's and the supply voltage.
  • Super Glue & compound glue. You can use other glue as well but super glue sticks fast and I recomend it.
  • solder wire, moderate soldering skills, solder gun
  • one small piece of 0.2mm aluminium sheet (this is used in printing industry, I work in this field and there are a lot of aluminium plates around here). Any offset printing shop will be kind enough to give you a used one since they use hundreds each month.
  • a paper perforator (office type, 2-hole punch)
  • resistors (depending on your needs)


a few other common household items along with a good amount of patience.





Step one - empty the bulb.

Start by taking a small screwdriver and twisting its tip on the white cement you'll see around the bulb's pins. This cement is very fine and will start crumbe as a fine powder as you keep twisting the screwdriver's tip.

Proceed with this until you get enough cement out for the next phase.





Patience is a virtue so take you time and be gentle since the bulbs can easily break if you force you way in with the screwdriver.





Action time. Take a hammer and after you got out out as much white cement you could, put the bulb face-down on a flat surface. Hit the two pins with the hammer, in a easy but ferm manner. The bulb inside should fall on the table leaving the reflector empty.





Some white cement will remain but that's OK, it's not so important and might even be useful later.





Step two - make your holding disc.

Put the empty reflector aside since it's time to get to another task. It's now time to make the LED support.

You'll need a template so make yourself one. I used graphic software to evenly distribute the 5mm holes on the disc. The disk size is up to you. More led's will require larger disks.

Print your template on paper and cut it out with paper scissors. Place it on the aluminium sheet and light glue it on its surface. This will be useful to cut the disc properly.





Take the aluminium sheet and cut out the holes using a office perforator. I found out mine cuts exactly 5mm holes in paper so for 5mm LED's it's perfect. Keeping it upside down, place the template along with the aluminium disc glued on it inside it. Cut out the holes after aligning the circles in the cutting hole. This should be easy and fairly quick. For this tutorial, I'll use 22 LEDs and a disk diameter of 4 cm. In this picture you can see another disk I made for 15 LEDs. It's easy and if you practice a little you can make this in minutes.





The aluminium sheet will serve as a light reflector and a holder for LEDs in the same time so take care not to bend it. After cutting out the holes it''s time to see how the led's should be connected.

Go to  http://led.linear1.org/led.wiz and fill in the fields with your parameters. Here's a screenshot of what the wizard reccomended for my 22 LEDs 12V array. So now I know how to connect them.





Place the aluminium disc in some holding device (I have one like the one in the photo and it's great). Be creative with this, basically you have to hold the disc by its outer rims. For example, a pipe section with proper diameter will do.





Insert the Leds into the holes with the legs up and arranged in such a manner that one cathode is next to another anode. This will make soldering easy. Don't forget this or you will have great difficulties soldering them according to the scheme.





Put one tiny drop of Super Glue on each led margin and continue arranging the other ones. WARNING! Take care not to accidentally apply super glue on the LED legs. When you'll have to solder the legs, these will be heated and the glue will give off a little colourless smoke with major effects on your eyes! I know, i've done that and couldn't stopped crying for one hour. I think that's how they make that tear gas after all ...





After all LED's are placed and glued, put compound glue around each LED for a solid result. It is necessary to glue them firmly since the legs will have to be bended and you'll risk some leds to come off otherwise. (that's experience speaking) Now let the glue to harden before proceeding. In my case this meant 24 hours but the result was worth it.


Step three - making connections


Take one nailclipper and cut out the LED legs, keeping in mind that one anode will have to be bent over to the next cathode and so on. Also take care not to confuse the two of them. You can check that with one multimeter set to diodes. As the scheme advises, I'll have to make 5 strings of 4 LEDs each and one string of two. Since I arranged the leds in such a fashion that one cathode is next to another anode, this operation is much easier. After soldering one string, keep the end legs at different lenghts to easily identify the + and the - end.





Take the nailclipper and cut the LED legs and bend them to the next leg. The + goes to a - and so on until you complete a string of four. Then start a new string.





When you're done making all the strings according to the scheme, you should have six + legs longer than the six - ones. It's time to solder the resistors. But first bend the longer legs toward each other and solder them to have all the + legs connected together. This should be done over the other connections keeping some distance to prevent short-circuits. The resistors should be soldered vertically to the - legs.





When soldering, try to be as quick as possible sice you'll be heating the LED legs close to their base and too much heat will damage them.





Now solder the resistors legs to each other in order to get a single - that goes to all the strings. Try to keep a low profile so that the whole thing will fit the bulb.





Now solder the final legs. Use copper wire (thicker) and keep in mind that one (-) has to be shorter.





The whole thing should now be pretty rigid since so many solderings were made.

But for your peace of mind, use a hot glue gun to fill the gaps so that no wire accidentally touches another. This is optional.





Now take the empty bulb and put the LED disc inside. The space should be enough if you maintained a low profile when soldering.





It fits perfectly. Push the LEDs until the disc touches the inner reflector.





Hold it still and get the compound glue now.





I used some bicomponent glue but any glue with increased consistency should do.

Just make sure it's strong enough since it will be the only thing that holds the bulb in one piece. Fill the space around the legs coming out of the bulb with as much glue it will take.





Wait until the glue hardens. In my case it took 10 min. and I held the LEDs pressed in the whole time. After it hardened, use a permanent marker to write on the base the + and - legs as well as the voltage it will use.





Now cut the legs so that it matches the original bulb legs, equal in lenght.





Job done! It's time for a test. Connect the bulb to a 12V battery (car or anything else providing that voltage). Hold your breath and...





It's working! The photo actually does not display the amount of light generated as it's blinding if you stare into it directly.

I had to seriously under-expose to make this visible. You can use any type of 5mm LED to make ledbulbs just make sure you know the forward voltage and current since it will be necessary when calculating resistors. I made blue, red, yellow and white ones, with successful results. I also made 6V LED bulbs I use in flashlights, replacing the entire flashlight mirror with one of this bulbs. In this case, the current consumption should be ( according to the scheme ) 220mA. It actually uses only 200 mA, or at least that's what my multimeter says.





Here are some LED bulbs I made, 12V and 6V ones. They generate virtually no heat and 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.

The type of LED's you use is important since a more dispersed light will be better than a concentrated one. You could also file the LEDs prior to making the bulb so as to have a more uniform light. These LED bulbs can also be used in 12V AC spot lamps if you don't mind the 50Hz flicker. But the best results will come out from 12V DC.


Many thanks to all the members of this forum. I learned a lot here and I felt the need to give something back. I hope it will be useful to many people. Feedbacks, comments and opinions are welcome.


Claude

« Last Edit: January 28, 2007, 09:52:43 PM by (unknown) »

gotwind2

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Re: How to make your own LED bulbs.
« Reply #1 on: January 28, 2007, 03:14:33 PM »
Great, beautifully detailed with a well written narrative.

You obviously enjoy what you do :)


How about a 120v/240v direct AC version? - (rectified first)


I'm sure Ghurd will be interested and a good help - he has kindly helped me before in all matters LED.


Ben

« Last Edit: January 28, 2007, 03:14:33 PM by gotwind2 »

fungus

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Re: How to make your own LED bulbs.
« Reply #2 on: January 28, 2007, 03:16:01 PM »
Wow! Very nice tutorial! Certainly looks much better than the LED lights I've made ;-)
« Last Edit: January 28, 2007, 03:16:01 PM by fungus »

fungus

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Re: How to make your own LED bulbs.
« Reply #3 on: January 28, 2007, 03:17:10 PM »
Also...

Just to say that LED's legs can be identified easily since the - is the shorter leg.
« Last Edit: January 28, 2007, 03:17:10 PM by fungus »

wooferhound

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Re: How to make your own LED bulbs.
« Reply #4 on: January 28, 2007, 03:48:33 PM »
Nice LED Calculator you found there

I have always used this LED calculator

http://ourworld.compuserve.com/homepages/Bill_Bowden/led.htm


Your lights look 347% better than the one I made that runn on 120vac



« Last Edit: January 28, 2007, 03:48:33 PM by wooferhound »

willib

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Re: How to make your own LED bulbs.
« Reply #5 on: January 28, 2007, 04:25:17 PM »
nicely done claude

that must have taken a lot of time to present , i know it takes me hours to do a long post..

thanks for sharing

ps hopefully i will be testing the Mini gen( outside) soon , the weather hasnt been to nice lately though..
« Last Edit: January 28, 2007, 04:25:17 PM by willib »
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claude

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Re: How to make your own LED bulbs.
« Reply #6 on: January 28, 2007, 04:31:03 PM »
Hello Ben,


Thank you for your appreciations. As a matter of fact, yes, I do enjoy what I do. From time to time, that is. This is a hobby of mine, hence the patience.


I would certainly be interested in 240V AC versions. Unfortunately the LED array calculator I found can not calculate voltages that high. I know Ac has to be rectified first, but it's that capacitor and resistor that makes me wonder. Such a LED conversion could be made using GU10 halogen bulbs as it has enough space to allow all the components inside its base. Actually i'm just guessing here, I never opened one up.


I'll send the link to Ghurd maybe he'll be kind enough to make his advices public here. Being a great guy, he usually is.

« Last Edit: January 28, 2007, 04:31:03 PM by claude »

claude

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Re: How to make your own LED bulbs.
« Reply #7 on: January 28, 2007, 04:35:38 PM »
Thanks!


It actually took a long time. 2 days for all the photos & text. But it's the least I can do for you fine people.


Claude

« Last Edit: January 28, 2007, 04:35:38 PM by claude »

commanda

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Re: How to make your own LED bulbs.
« Reply #8 on: January 28, 2007, 07:28:29 PM »
A word of caution; a nominal 12 volt battery will typically be between 11 and 15 volts. Using a 1 ohm dropping resistor means the current will increase by a great deal when the battery is at 15 volts.


I would suggest that the strings should be 3 leds in series, not 4. This will calculate to a much larger resistor, hence the current will not vary as much as the battery voltage changes.


Amanda

« Last Edit: January 28, 2007, 07:28:29 PM by commanda »

tecker

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Re: How to make your own LED bulbs.
« Reply #9 on: January 29, 2007, 05:35:04 AM »
Yes 7812 is cheap enough
« Last Edit: January 29, 2007, 05:35:04 AM by tecker »

Nando

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Re: How to make your own LED bulbs.
« Reply #10 on: January 29, 2007, 07:06:57 AM »
If you need assistance for a 120 or 240 AC volts string, let me knowa nd I do the calculations and the set up.

The circuit may need a AC Capcitor to reduce the power usage if the string is not long enough, ideally three ( 3 strings) of 20 milliamps may be best using a 3 UF capacitor.


Nando

« Last Edit: January 29, 2007, 07:06:57 AM by Nando »

Nando

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Re: How to make your own LED bulbs.
« Reply #11 on: January 29, 2007, 07:08:37 AM »
If you need assistance for a 120 or 240 AC volts string, let me know and I do the calculations and the set up.

The circuit may need a AC Capacitor to reduce the power usage if the string is not long enough, ideally three ( 3 strings) of 20 milliamps may be best using a 3 UF capacitor.


Nando

« Last Edit: January 29, 2007, 07:08:37 AM by Nando »

ghurd

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Re: How to make your own LED bulbs.
« Reply #12 on: January 29, 2007, 07:12:04 AM »
Hi guys,

Beautiful bulb!

I like the use of aluminum.


I concur with Amanda's statement regarding the resistor values, voltage, and 3 LEDs per string.  A just charged battery will have higher voltage and the current will rise dramatically.

I usually design for 18ma at 14.4V.


Simple line powered LED bulbs are a problem.

For 120VAC, it could handle 50 white LEDs in series.  220VAC could handle 100 LEDs.

The problems are, if one LED fails to an open state (common) the bulb is shot, and if one LED fails to a shorted state, the voltage rises on the other LEDs, raising the current, leading to more LED failures.


Line power into LEDs could often be better utilized.

The 20ma at 120VAC is 2.4W, and 4.4W at 220V.  A CFL gets my vote for better use of power and longer life than very long strings of LEDs.


LEDs can be line powered other ways, but it can get complicated.  The losses get higher and there are more parts to fail.  

Personally, for grid powered LEDs, I would prefer to grid-charge a battery for the LEDs.  It's easier!

G-

« Last Edit: January 29, 2007, 07:12:04 AM by ghurd »
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Nando

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Re: How to make your own LED bulbs.
« Reply #13 on: January 29, 2007, 07:17:53 AM »
Heck !!


My post was sent twice.

I went to check for any errors, I corrected them, and when I sent it, Yahoo reported as sent already when I sent the second, I went to see if such have occurred and it did, showed two posts.


I am wondering that there is a glitch in Yahoo group software.


Nando

« Last Edit: January 29, 2007, 07:17:53 AM by Nando »

richhagen

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Re: How to make your own LED bulbs.
« Reply #14 on: January 29, 2007, 09:54:15 AM »
I built a 120VAC one that way and learned the hard way.  It was several strings 44 LED's in Series with rectified line voltage with some capacitance to reduce the ripple.  After a year or so of service, most of the strings had failed.  I am of the opinion that one would be better off to get a high efficiency switching power supply to bring the voltage down lower and then run shorter strings with resistance.  I also saw those 1 Ohm resistors and thought it was not that good for 12V.  If you have a small spike in voltage, you could over-current your LED's, and if one fails to short, you will lose the string.  I have used three in series with a 180 Ohm resistor, which for LED's that can handle 25mA max, and 20mA typical, offers a bit more protection at the expense of losing a little energy in the resistor.  Still the trade is worth it in my opinion.  Rich
« Last Edit: January 29, 2007, 09:54:15 AM by richhagen »
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claude

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Re: How to make your own LED bulbs.
« Reply #15 on: January 29, 2007, 10:10:32 AM »
Hello Nando,


Yes, I do need assistance for 240V but I wanted to take a ready-made bulb abd modify it for AC. Take for example the bulb I made here. It has 22 LEds of 20mA & 3V each. There are 5 strings of 4 leds and one of 2. What will I need to use it with AC? I assume I will have to make another wiring but how many should I fit on a string? I wouldn't want to make a single string of all these leds since if one fails, all of them will.


Claude

« Last Edit: January 29, 2007, 10:10:32 AM by claude »

claude

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Re: How to make your own LED bulbs.
« Reply #16 on: January 29, 2007, 10:20:10 AM »
Hell Ghurd! Nice to have you here.


Ok, ok, I got it. I overrun the LEDs a little. Next time i'll be more cautious. They were cheap anyway :-)


I got the point that line powered LEDs are not such a great idea. But what about the commercial bulbs? How are the made? I never opened a 220V one so I don't know what they use in terms of electronics. There has to be some better way of using line powered Led's as the LEDs business over here starts to grow dramatically.


I see building lighted with leds, I see commercial signs illuminated with LEDs too...


Here's my LED supplier. The page is in english too so it should be easy to get my point.

http://www.zexstar.com/english/index.php?cat=26#

« Last Edit: January 29, 2007, 10:20:10 AM by claude »

ghurd

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Re: How to make your own LED bulbs.
« Reply #17 on: January 29, 2007, 11:13:52 AM »
I only saw the insides of 1 line powered LED bulb that I remember right now.  It was a terrible design, with worse worksmanship.

The design looked like it started as a 12VDC bulb with 3 LEDs per string.

The AC was rectified, a capacitor was added, and the resistor(s) were a higher value.

It could have been only one resistor, but I can't recall for sure.

So 12 LEDs used (guessing) 120ma at 120V, or about 14W!

It didn't last long.


The saddest part is the owner bought it to run it from a 12V inverter.

G-

« Last Edit: January 29, 2007, 11:13:52 AM by ghurd »
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ghurd

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Re: How to make your own LED bulbs.
« Reply #18 on: January 29, 2007, 11:35:52 AM »
Oh... I think if I did one, it would use a 16~18V transformer and 5 LEDs in series per string.

Or a switching power supply from a laptop (the battery charger cord), but it would not fit inside the bulb.


The only commercial LED sign I ever saw up close must have a supply for each LED.

"Each LED" was a cluster of 3 LEDs, red, yellow, and blue. I have a closeup photo, somewhere.

It is in New York City in the NBC building.  This photo is not so great, but it's all I found on the internet.

http://www.nbcnewmedia.com/gallery/nbcExperience/globe.jpg

G-

« Last Edit: January 29, 2007, 11:35:52 AM by ghurd »
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dinges

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Re: How to make your own LED bulbs.
« Reply #19 on: January 29, 2007, 11:58:10 AM »
Last time I checked, CFL was more efficient than LEDs on a Lumen/Watt basis. (More correctly: CFL has higher efficacy than LEDs)


From an energy perspective it still makes sense to use CFL over LEDs. The lighting of buildings with LEDs has a high gadget-factor, but is not the best thing if you want to minimize power consumption.

« Last Edit: January 29, 2007, 11:58:10 AM by dinges »
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claude

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Re: How to make your own LED bulbs.
« Reply #20 on: January 29, 2007, 01:00:21 PM »
Ok ghurd, you got me convinced.


I'll head for the fluorescent department now. No more fancy 220V LED bulbs anymore. In fact, I did made some fluorescent inverter bulbs for 6 and 12V but they were a little power-hungry for my taste. The consumption depends on the light output. It's all about a pair of resistors. A 12V/0.5A bulb I made will give enough light to stop you from bumping into things but if you really want light, 0.8-1.0 Amp/h is the way to go. This also comes with heatsinking so bye bye economy.


Yes, it's sad what that owner did. I imagine that bulb wasn't cheap. I feel sorry for him.

« Last Edit: January 29, 2007, 01:00:21 PM by claude »

nothing to lose

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Re: How to make your own LED bulbs.
« Reply #21 on: January 29, 2007, 01:09:00 PM »
Great work and great post.


You did a far better job of converting a bulb (and it looks alot better) than the rechargable halogen flashlight I converted to led. Your bulb probably works better also.


I just took the bulb out of the flashlight and drilled holes in the reflector, glued in the leds and wired them together. Connected one side of the string to Neg and other side to Pos, and it worked fine. One of those $20 rechargable big fat halogen spotlights that works for about 20 minutes on a full charge, worked forever it seemed converted to led. Less light but I wanted it to see walking outside at night in the yard not spotlighting planes overhead anyway.


It was either 12V or 6V battery in it and I did not use resistors, just cheapo LEDS I had on hand from China probably (I had about 100).

I think the wife lost it, if I can find it maybe I'll get a pic of it, but I haven't seen it for a year probably.

« Last Edit: January 29, 2007, 01:09:00 PM by nothing to lose »

vawtman

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Re: How to make your own LED bulbs.
« Reply #22 on: January 29, 2007, 02:59:33 PM »
Ghurd, what do think of these new c-9 christmas bulb led conversions?I would need alot for a city.It gets pretty labor intensive every year changing bulbs only to have the ones that were working burn out shortly after putting the decorations up.

 I believe the glass is replaced with plastic material and pretty tough against breakage.Im a little gittery about trying them.

 One company has a 5yr warranty on them.

 You can use the existing socket also.
« Last Edit: January 29, 2007, 02:59:33 PM by vawtman »

claude

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Re: How to make your own LED bulbs.
« Reply #23 on: January 29, 2007, 03:43:38 PM »
Thanks,


Well, I don't know, my bulbs do work well for 6 and 12V. The amount of light one can gain with cheap LED's is very limited. Not necessarily in quantity but in quality. The light is generally very focused. It gets frustrating to mount 22 LEDs just to get a larger spot of light.


Don't get me wrong, I like this light output. It's just that I prefer, like you, a wider area than the tight beam I usually get. But it's just the LED's, I only bought cheap ones so I'm not really complaining.


I also thought about drilling holes in one reflector. But then I realized I would better drill led holes on some hemispherical surface to spread the light more evenly. Being a perfectionist, I didn't managed to drill the holes properly aligned and this made me dump the idea that day. Nevertheless, I still think it would come out better than on a flat surface. Maybe on some sunny day I will manage to properly drill the holes.


Believe it or not, the first bulb I made was intended to light up my desk from a standard desklamp connected to a power supply. Needless to say that after more than 10 bulbs and 2 months I still have no light on my desk, isn't it? These days i'll solve that problem, the shame is just too much :-) .


Claude.

« Last Edit: January 29, 2007, 03:43:38 PM by claude »

Nando

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Re: How to make your own LED bulbs.
« Reply #24 on: January 29, 2007, 05:35:17 PM »
This thread has become a very long one, filled with NON-decisions.


It is hard to do something common for many at the same time.


Several strings of LEDs to have light if one string fails presents problems in a simple design because from the beginning 3 strings maybe needed ( 3 separated systems).


There is another solution with limited capabilities and it is a single string with a capacitor to limit the current and a group of transistors ( behave like SCR's) to short circuit damaged devices (it does complicates the design a lot).


It is best to insure that the LED's have the limited current stable for maximum life.


3 strings can be made in parallel and fed by a capacitor to avoid having a transformer IF an Integrated circuit is not warranted or desired.


SUPERTEX produces several types of Integrated Circuits specially designed for High Voltage AC driving strings of LED's


So what is the decision ?.


Nando

« Last Edit: January 29, 2007, 05:35:17 PM by Nando »

claude

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Re: How to make your own LED bulbs.
« Reply #25 on: January 29, 2007, 11:44:48 PM »
Nando, it's true this has bacome a long post. But it was long right from the begining. About 240V AC version, I wrote my decision somewhere down here, I won't make one since it obviously poses efficiency issues. I'll use a 12V power supply for the LED bulb. Having no access to specially designed IC's and being electonically challenged, it's the easiest way one can light up LED bulbs using AC.


From a reusable energy point of view, the 12V version should be enough. As tecker said, 7812 is cheap enough and that solves the variation problem. For small solar arrays this should be the choice for lighting. 22 LED's eating up a total of 2.4 Watts should please some folks. I presented here a way to make LED bulbs and that's all there is to it.

« Last Edit: January 29, 2007, 11:44:48 PM by claude »

ghurd

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Re: How to make your own LED bulbs.
« Reply #26 on: January 30, 2007, 08:42:01 AM »
Claude, The 7812 needs 13.5~14V to operate properly.  I suggest a 'low drop out' 7810 for 3 LED and a resistor for use with a 12V battery.  I found it not worth the effort for most bulbs in most uses.  (Simple resistance helps show the condition of the battery)


Vawtman, I never saw those bulbs.  I would not have much confidence in the warranty unless the brand name is old and common.  I was pleased with the factory LED strings I looked at.  

Makes me wonder why... they include extra LED replacement bulbs?  LOL


G-

« Last Edit: January 30, 2007, 08:42:01 AM by ghurd »
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whatsnext

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Re: How to make your own LED bulbs.
« Reply #27 on: January 30, 2007, 10:18:34 AM »
"From an energy perspective it still makes sense to use CFL over LEDs. The lighting of buildings with LEDs has a high gadget-factor, but is not the best thing if you want to minimize power consumption."


This is true most of the time except when just a small amount of light will do. The smallest CFLs are about 3 watts and not all of them are useful. So if low light or highly concentrated light is needed LEDs can best CFLs.

John..

« Last Edit: January 30, 2007, 10:18:34 AM by whatsnext »

vawtman

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Re: How to make your own LED bulbs.
« Reply #28 on: January 30, 2007, 11:34:54 AM »
« Last Edit: January 30, 2007, 11:34:54 AM by vawtman »

Gordy

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Re: How to make your own LED bulbs.
« Reply #29 on: January 30, 2007, 01:13:44 PM »
Vawtman,


I couldn't get that link to work. Check them out at the link below, 50 , 5 led bulbs for $70.oo for the c-9's. How do these compare to the ones you found?


http://www.creativedisplays.com/siteresources/modules/webstore/scripts/prodList.asp?idCategory=37


Gordy

« Last Edit: January 30, 2007, 01:13:44 PM by Gordy »

wayne

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Re: How to make your own LED bulbs.
« Reply #30 on: January 30, 2007, 03:19:32 PM »
Nice write up and anyone want to try 120vac could look at this http://www.newcircuits.com/project.php?id=prjsub002


Wayne

« Last Edit: January 30, 2007, 03:19:32 PM by wayne »

vawtman

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Re: How to make your own LED bulbs.
« Reply #31 on: January 30, 2007, 03:55:35 PM »
Gordy im sorry it didnt work.Those are what i found on the other sight.

 I retrofited many many exit lights around 10yrs ago with led boards and none have failed yet.Boy thats alot of hours running 24 hours a day.


 So one day i thought maybe they made c9s led bulbs and found them.Seems lots of companies(sights getting in this).Maybe the price will come down has a result.


 Thanks for helping

« Last Edit: January 30, 2007, 03:55:35 PM by vawtman »

Bruce S

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Re: How to make your own LED bulbs.
« Reply #32 on: January 31, 2007, 11:17:56 AM »
Claude;

   I would like to add to the very nice tutorial. We use the MR16 bulbs which are very close to what you have.

Using your posts, I was able to also knockout the burnt bulb and found that by using an old mobile phone plug, and resistor make the LEDS light up very nicely.

The bulb that I tried first are the 4-point ones that have a lot of light coming out of them. One bulb sits in the base and looks very nice just hot-glued to it. a couple wires a resistor and the 120Vac to 3.7Vdc phone charger TADA! nice pretty light.

Once I have the chance to get a pic and on a computer that is a little faster than 56K dialup I will up load the pic.


Thanks Again for the well laid out tutorial.


Cheers

Bruce S

« Last Edit: January 31, 2007, 11:17:56 AM by Bruce S »
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