LED revival

[mark]

At the Home show in Edmonton, someone had a booth showing LEDs for lighting outside of houses.

Might still have their card.

[mark]

Found the card for the exterior LEDs. Might be something there for adapting to a DIY hood.


http://www.starlexinc.com/index.shtml

[AndyL]

I had a 2g freshwater planted tank running on LEDs, they were only the 8000mcd LEDs, and I'll tell ya 12 of them lit up the tank way better than the 2 13w pc's they replaced...

I just finished testing out some 20,000mcd LEDs (from LKCWTC on ebay), ordered 100 more - for the new 5g nano for my desk at work. Nice color, probably in that 12-14k range.

Just trying to come up with a good way to mount them - was going to install them in drilled acrylic - but then I realized - acrylics a very good insulator - and heat is an LED's biggest enemy... So I'm trying to find another more elegant solution.

Andy

[Invigor]

Originally Posted by AndyL

I had a 2g freshwater planted tank running on LEDs, they were only the 8000mcd LEDs, and I'll tell ya 12 of them lit up the tank way better than the 2 13w pc's they replaced...

I just finished testing out some 20,000mcd LEDs (from LKCWTC on ebay), ordered 100 more - for the new 5g nano for my desk at work. Nice color, probably in that 12-14k range.

Just trying to come up with a good way to mount them - was going to install them in drilled acrylic - but then I realized - acrylics a very good insulator - and heat is an LED's biggest enemy... So I'm trying to find another more elegant solution.

Andy

what do you use to power them, and which are the 12-14k ones? the blue or the ultra white? for the price this guy's selling these at, they look like fun to play with!

[AndyL]

Originally Posted by Invigor

what do you use to power them, and which are the 12-14k ones? the blue or the ultra white? for the price this guy's selling these at, they look like fun to play with!

I just use a typical 12v wallwart - puts out a pretty consistant 14.4v - which is perfect for driving arrays of 4 (3.6v to each), add in a 700ohm resistor - and you've got 20ma @ 3.6vdc.

Watch for his auctions that start at >10$ I got my first 20 LEDs for 7.99. The most recent purchase wasn't only 28$.

And the blues are much too blue for regular use - just the regular ultra bright white or whatever he calls them.

Andy

[StirCrazy]

Originally Posted by Invigor

Just trying to come up with a good way to mount them - was going to install them in drilled acrylic - but then I realized - acrylics a very good insulator - and heat is an LED's biggest enemy... So I'm trying to find another more elegant solution.

shouldent be a problem with using an acrilic mount, LED light lights come sealed in acrylic blocks and they last for 10 years...

for what it is worth I am going to encase mine in acrylic (liquid that hardens) in small strips as I won't be able to change a bulb or anything once I cast them. this will make them totaly impervious to water and they will even be able to be used submerged (got a few accenting ideas I want to try out also )

STeve

[AndyL]

In theory thats right, in application, I learned from the 2g that it's not.

Mounting within acrylic (or in my case on the 2g within epoxy) the heat tends to be captured and retained. Results in a short lifespan. Yes the LEDs themselves are made of acrylic - but the amounts are minimal, surround several of them in a small area - and they do retain the heat a little too well.

My plan at the moment is to find a nice hunk of aluminum to drill, aluminum is very efficient at moving heat away - and transfering the heat - thus keeping the LEDs running cooler.

Andy

[StirCrazy]

Originally Posted by AndyL

In theory thats right, in application,

Andy

so how do we explain my solid acrylic LED night lights I have had for over 5 years? if we shorten the life span from 11.45 years (running 24 hours a day) to 5 years at 24hours a day then we still get 10 years average life @ 12 hours a day. now another option is to have a fan blowing on the LEDs to aid in disapating heat, I can't see the problem as I can hold on to my leds for ever after they have been running for a few hours so not much heat is produced.. .

Steve

[AndyL]

But you're forgetting one major issue... The older LEDs did not have near the same power (mcd ratings) - or heat production the new ones do.

I could take some radio shack LEDs and encase them in acrylic and it wouldn't be a problem - try that with the newer >12,000mcd units and it is an issue.

Andy

the one watt leds I have get hot, hot enough that they are to hot to hold, the 5 watt led's I have get smoking hot and must be run with a heat sink unless testing for only short amounts of time, they will make your skin go sssssssss and leave a nasty blister....


you will see what I mean Steve.....