Powering 30w LED?
Posted 08 September 2009 - 04:49 PM
Posted 08 September 2009 - 05:37 PM
Posted 08 September 2009 - 08:32 PM
What do you think?
Posted 08 September 2009 - 09:59 PM
Posted 09 September 2009 - 07:57 AM
Just planning it out at this point, no it doesn't have a constant source, that's what I'm trying to figure out. I wished it could connect directly to batt but need a little more voltage. There are LED drivers which can connect to a source and then up it to 16v but they are expensive, I was just curious if there was another way.
These are the 30W LED's that I'm going to buy;
I have a 10W and a 12W already but they're for different applications(one was to replace flash light(I have to say these things are insanely bright!), the original was to mess with, didn't realize they needed to be attached directly to heat sink with heat paste and burned up 7 of the 9 LEDs on the board). The messed up one is still bright but no where near the original good condition.
So far the cheapest way I can think of is to buy a cheap LI-po charger from hobbyking, a cheap 4s lipo to the charger and connect the lights to the lipo. It would cost me 20-25 bucks that way versus... geez thought i found a couple the other day but pretty much everything I've come across is ac to dc!
The one from digikey which does specifically what I want is only 206 bucks.
Posted 09 September 2009 - 08:55 AM
Posted 09 September 2009 - 11:13 AM
Posted 09 September 2009 - 03:19 PM
Must be coming from China. I'd try it on your battery first. Might be bright enough. BTW, Batt voltage & charging system should be same as a car. You can use one of those 3 terminal regulators hooked up as a constant current source.
I'd just get another pb cell or two & hook it up in series with the bike battery. Charge it seperatly from the bike battery.
You have to disconnect a lipoly charger when it's done charging. They're finicky about charging. I'd look more toward LifePo4 batteries or A123 if you go that route.
Edited by W3FJW-Ron, 09 September 2009 - 03:35 PM.
Posted 18 September 2009 - 11:18 PM
Posted 20 September 2009 - 06:30 PM
Sorry Xygax, I totally didn't understand your reply, just a bit too technical(or at least the terms used) for me .
Posted 21 September 2009 - 12:22 AM
What matters to a LED is current, not voltage. Your LED as shown on the seller's page needs 1.8A to run at full brightness, but voltage can have to be anywhere between 15 and 18V, and will be different for each LED. And a little change of voltage will induce a large change of current, so maybe yours will require 17.16V, and if you supply 17.1V it will run dim at 0.5A, while if you give it 17.2V it will burn up with 2.5A...
So, you need to buy or make a circuitry that will regulate the LED current, by automatically continuously adjusting the voltage so that the current in the LED is what it should, i.e 1.8A, which is what the previous 2 posts gave hints on how to make
Posted 24 September 2009 - 07:33 AM