extreme direct drive

[daich]

Having the benefit of being 4sevens brother, I raided his old stash of discarded luxeons.

here it is, 38 old Luxeon 1 watts in serial epoxied to an edge of a ruler.........jacked directly into 110v wall power !! :

it flickers at 60hz which is irritating to the human eye.
makes for nice effects on video: http://video.google.com/videoplay?docid=-931149326316374823&hl=en
need a power rectifier or something.

Heats up to a scorching 150 degrees F

Beastly.

can't wait until the cree's become disposable.....

 

[4sevens]

benefit of being 4sevens brother, I raided an old stash of discarded luxeons.

here it is, 38 old Luxeon 1 watts in serial epoxied to an edge of a ruler.........jacked directly into 110v wall power !! :

it flickers at 60hz which is irritating to the human eye.
need a power rectifier or something.

Heats up to a scortching 150 degrees F

And to think that ALL of those Luxeons came out Fenix L1P's that I upgraded to UWAJ's. HAHA!

By the way, it's not a ruler. It's my old level from biglots!

 

[Gryloc]

Sweet "ghetto" light fixture! Nice job! What current is each LED seeing? You should find a place to use that thing, like a garage or something. Yeah, it would be a good idea to add some rectifying diodes. That will make the light more pleasant. Might as well add some resistors while you are at it if you plan on using it longer.

Too bad that all those good 'ol Luxeons are being used like that, but oh well! They were collecting dust before, right? Imagine showing a picture like this on CPF 4 or so years ago. You would have been beaten, or just shunned! Lol. Well, lets hope that your light gives you some more years of service...

-Tony

 

[koala]

Those are R bins, premium for those days standard... I suspect they are also H-J vf because mine is 3.22v@350mA.

 

[amanichen]

Might as well add some resistors while you are at it if you plan on using it longer.

Why?

The series voltage drop, for instance, if each emitter is carrying 3.0V across it:

3.0V * 38 = 114V, which is basically what most household outlets put out. The LEDS are probably being driven close to spec, other than being driven by AC and not a switched or rectified DC power supply.

 

[bombelman]

I like it !!

Great idea IMHO...

 

[evan9162]

Why?

The series voltage drop, for instance, if each emitter is carrying 3.0V across it:

3.0V * 38 = 114V, which is basically what most household outlets put out. The LEDS are probably being driven close to spec, other than being driven by AC and not a switched or rectified DC power supply.

No, that's wrong.

US AC power is 110-120VAC RMS. Peak voltage is 156-170V. So at the peak of the sine wave, there's 4.1-4.47V across each LED. You're looking at probably 2A hitting each LED at the peak of the sine wave. Some kind of current limiting device is strongly recommended.

 

[Marduke]

With a few tweaks, you have the making for a really sweet shop work light to replace a drag light.

 

[Gryloc]

I was just going to say that about the true AC voltage. I learned about that a while ago and found that so interesting. Your volt meter can be decieving for AC. Plus I thought that he could use a resistor since he indicated how overdriven the light is because the light fixture (the aluminum level -a good idea by the way) is getting too hot. You will have to add resistors to it for sure once you rectify that AC to DC, since the duty cycle of the LEDs are getting closer to 100%.

Well, at least you are getting some decent lumens from that light fixture (being overdriven R-bins). Now, when are you going to upgrade those suckers to some Seoul P4s or some XR-Es? :naughty: Lets hope this stays a long burning light. Try to get as much use out of this thing as you can! Good luck. :thumbsup:

-Tony

 

[daich]

video added....nice effect with the 60hz flicker

 

[VidPro]

cool, its about time we see more of this, after all you can get enough emitters to do a wall plug in for $70 or less.

to reduce the flicker , do a second set, then run them reverse to the other set, then the visable flicker is much reduced, one is going up while the other is going down.

course, like was said above, the peak of the sine curve is enough to ruin the life of the leds, from my experiance, over time its glory will fade :-(
while they can handle the peaks heat wise, because its not constant, the voltage highs will still age them quickly.

 

[chesterqw]

woah...