LED Replacement Fluorescent Tube

In this instructable, I will try and outline all of the steps required to create an LED fluorescent replacement tube. This instructable is provided more as a guideline, you can change almost anything in here to suit your needs. The lamp I created contained 87 LEDs, and this guide provides instructions for that many. This instructable contains the information on how to build a lamp, but there is too much information about how it works to include here.

The approximate cost is $25.00 per lamp.

If you would like more information than this instructable can provide, check out the website for this project. http://led.hypertriangle.com

When I finished this project, I was very satisfied with the results. The light produced from 87 LEDs is very usable. You can see graphs of lux if you are interested at the website above.

The best part about this project is saving energy. The 87 LED lamp uses a mere 8.4 watts! (0.7 amps @ 12VDC)

This project was seen at the Intel International Science and Engineering Fair (IISEF) and the Bay Area Science and Engineering Fair (BASEF).

Help us out and digg this story!

Step 1 Materials Required

You will need an array of materials for this project.

T12 Fluorescent Tube Protector
48" x 1.5" x 0.25" Plexiglass
87 Super Bright White LEDs
29 2.7 ohm 1/4 watt Resistors
2.5m 18 AWG Bare Copper Wire
20cm 14 AWG Bare Copper Wire
Solder/Flux
LM334
TIP32C
ZTX948
1k ohm 1/4 watt Resistor
100 ohm 1/4 watt Resistor
0.2 microfarad Ceramic Capacitor

Suggested Suppliers:

For the LEDs, if you are building your first buib, I recommend LED Shoppe. They have sweet deals on LEDs. The only problem is that they dont carry the most efficient or recent diodes.

For the bare copper wire, the 18 AWG can come from an old scrap of RG6 and the 14 AWG can come from Romex House Wiring.

The tube protector comes from most hardware stores.

Almost every other component there can be ordered from Digikey or Mouser

Comments

[jjmaia]

Hi there.

How did you "difuse" the led's?

Thanks

[hanlin_y]

To increase the viewing angle? Use sand paper.

[hirenpanchal47]

why you did not use SUPER FLUX LED , Did you tested it ...? See drawing & make one tube . after use this tip you will gate more light than your tube ..

[computerwiz_222]

What is the advantage of using an LED pattern like this? Does it affect light scattering?

[hirenpanchal47]

Yep this will Give more light without dark lining .
try it , make it and compare .
i promise this will give more light .

[hirenpanchal47]

Ya. this will effect . you will have more light .

[Helenchina]

Hi, i m the new comer here, i think LED tube lights have many advantages, energy saving, usually we can use 12W T10 120cm LED tube to replace our normal fluorescent lamp 30W, so you know its effective energy saving.
second LED tube light have long lifespan, 40000 hours more, keep eyes, no noise, can work under high voltage. and there are many advantages.....

[supersuper]

LED tubes are all hype, and completely experimental. Not to mention expensive. They say led tubes last 40000 hours. But this is hypothetical. LEDs are very temperamental and burn out all the time. Just look at traffic lights with missing pins. They are also meant for directional light. the whole point of a fluorescent tube is to light a space. Look at the light output in te picture above. It's a spotlight. The power supply for large amounts of LEDs uses almost the same amount of power as one for fluorescent lighting. Modern fluorescent transformers also make no noise. LEDs are great for a lot of things: Indicator panels, traffic lights, cell phones. But they are not efficient for applications where you need to light a large space or for advertising. Fluorescents and neon shine 360 degrees versus LEDs which are pretty much just directional light.

[Helenchina]

If you choose low quality LEDs, then the led will burn out often. before you choose the led, you need to test the led from different factories, test the leds at least two years to see if there is problems on the leds. after two years testing, you will see the led quality, if good then use, if not no use.....however, there is light decrease with the led tubes, no matter what kind of leds you use, the main point is how much light decrease.....

[bkeaton]

Test an led for two years?? Are you serious??

[Helenchina]

Yes, test two years, and see its illumination decrease, means when you test the leds from the begining to the two years later, how much lux lost?
usually for good leds and some famous brands its about 0.3% in 3000hours.
But we are only making complete tubes, but we need to test the leds, and choose the best to use, offer best quality to our clients. For more you may visit our website www.topuledlight.com, thanks

[cowen]

There is a place here in Plano Tx that makes fixtures to replace every sort of lighting from spot to flood and area lighting.

The key is mirrors.

Yes if you just put a ton of LEDS in a housing and power them all you are doing is making a LIGHT ENGINE just like a floresent tube is.

they have some patented method of using LEDS and mirrors to disperse the output and direct it using far less LEDS.

It is pretty neat to see how it is done.

[Yaka07]

I am very interested in building on of these just to compare to a normal tube
After building do I just replace the normal flourescent tube with this? Or will I need to make some adjustment to the balast? also as I am in the UK do I build the small circuit as is or do I make some changes?

[Helenchina]

if you want to replace the normal flourescent tubes with led tubes, you need to buy T8 or T10 led tubes, T8 is recommended mostly. When you install the led tubes on the normal flourscent fixture, you need to cut the ballast in the fixture also remove the starter, then in stall....and switch on

[richardcole]

CAN U TELL ME WHY WE USE TRANSISTORS IN LED CIRCUIT, AND CAN U SEND ME THIS TUTORIAL CIRCUIT DIAGRAM PLZZZZZ

I HV MANY QUESTION TELL ME IN PERSONAL MSG....

[chetan_m.p]

where can i find this circuit diagram???

[bumsugger]

Er,where (in the UK) can I get hold of such as thing as a "T17 fluorscent tube protector?"

[computerwiz_222]

Its T12, and you can get them at most hardware stores for around a 2 bucks - they are a pretty common place object. They are used in those convenience store fridges with milk in them so that if the tube breaks, the glass is kept (relatively) intact.

[agis68]

very clever indeed!!
Now what is the limit (down and up) of LEDs you may use? Lets say if you should replace a 4W lamp?

[computerwiz_222]

i'm not sure that I understand your question.<br /> <br /> If you are asking how many LEDs you can fit into a tube, it is up to you. As many as you can fit is the limit, just make sure you heat sink that circuit because with each additional LED, it runs hotter and hotter. With 87 LEDs, it dissipates approximately 3 watts of heat. <br /> <br /> A general rule of thumb is that you need 1inch^{2 of surface area per watt of heat generated. Use copper if you can.<br /> <br /> <br /> Maybe clarify what you want to know... I would be glad to answer.<br />}

[sanjo]

If one so clueless, just forget it.

[orangesrhyme]

Incredible idea. Will it light a room as well as a mercury tube?

[computerwiz_222]

Depends on the size of the room. From personal experience, a 10 x 10 room can be dimly lit if a diffuser is used. This lamp is ideally installed over a work bench to provide bright light on a spot.

However, if you are willing to spend the time when these lamps are used in multiples they are very capable of lighting a room. I created four of these lamps for our project and we lit an entire room with three of them. The reason is because they are highly directional with light only coming from 20 degrees of the entire lamp.

Thanks - check out our site LED Ideas There are more pictures and graphs of light intensity.

[orangesrhyme]

I see. So, if I decided to point them in all directions instead of one, it would light more of an area?

[computerwiz_222]

That is actually one of the intended installation. If you had 2 tubes in a fixture, you would aim them apart from each other to provide light to the whole room. We tried this, and it works good.

[DeadlyDad]

One way to have the holes face away from each other would be to place the strip on an old binder when you drill the holes. That should give you 10-20 degrees of tilt.

[orangesrhyme]

Gotcha. Definitely a project I'll be trying in the future.

[cloner]

what kind of diffuser did u use? and what are other alternatives? thanks :)

[computerwiz_222]

We created our own diffusers by taking a plastic tube protector and giving it a light sand with a high-grit sand paper. Check our site in the near future for more information about this.

[frollard]

Wonderful build. I picked up some 1 amp led mains drivers from dealextreme for 3 bucks...definitely a good idea to use them for!

[DeadlyDad]

Link, please.

[frollard]

http://dealextreme.com/details.dx/sku.13552

[DeadlyDad]

Thanks! hehe Imagine building this with a set of these 12W puppies. You'd want a 120mm tube, so you can fit the heatsinks and fans at each end. :D

[luvasu]

Adding to my comment. Pictures done with dark street, no flash and no other lights on. Just THREE of my "light points". Connected to a battery of my "experimental small solar supply" (15 W solar pannel to a 7A/h battery). Total of the three lights drain 300mA. The led single rows, with the same connection method are still to be finished as environmental light to watch TV.

[luvasu]

At 10 inches distance gives 4000 lux (+/- 3%). At one meter 480 lux, enough to read a book or a newspaper. Ceiling light gives, at my dining table level, 225 lux easy to eat, but not enough if a fish in in your dish.

[computerwiz_222]

There is a problem with driving LEDs at a variable voltage... As the input voltage changes, the current through the LEDs changes. This can cause premature failure and brightness variation as the day goes on.

[luvasu]

As the lights are used night time and solar panel is off, the voltage starts at a full battery (in my case 13,65 vdc - nominal float voltage), that means the voltage is only decreasing with the use. The worst for LEDs is the voltage up/down variations, in this case it goes only down very slowly. As I wrote, two full months working this way and no failures... let's see after one year.

[BearWayne]

Very clever project! One thing that is not clear to me is the power source--can this be inserted into a fluorescent fixture as a direct replacement, or must the fixture be modified (as in remove ballast & rewired) in order to use the led version?

[computerwiz_222]

Well, there are two installations that can be done. One is to install a switching mode power supply into the fixture in place of the ballast. The other is to completely remove the ballast and wire up an alternative 12 volt source such as the batteries in a solar or wind energy based home. The second method is preferred for many reasons.

[rmcatee]

Now plug it into the lamp socket and watch the thing go up in flames because you forgot to remove the high voltage ballast! Very scary project.