coolwaters Posted July 24, 2007 Author Share Posted July 24, 2007 whats up with the AC adapters? i was testing the 15v 1 amp and it gave me 13.8v and 7.5amps... and the 3-12v 1.3amp was a little better just the amps was at 3.8... now im going to need to use those regulators... Link to comment
coolwaters Posted July 24, 2007 Author Share Posted July 24, 2007 i used the regulators and resistors...and dam it gets hot... is there something i can do for that? each LED is running at 3.2-3.5v and at .7-.8 amps which is good enough. but the resistors and regulators heat is a problem... Link to comment
Socalsuperhero Posted July 24, 2007 Share Posted July 24, 2007 i used the regulators and resistors...and dam it gets hot... is there something i can do for that? each LED is running at 3.2-3.5v and at .7-.8 amps which is good enough. but the resistors and regulators heat is a problem... Resistors are going to do that. Think of them like brakes, they scrub off electricity and turn it to heat. As long as you have proper watt rated resistors then it shouldn't be a problem. That's why current regulators are a better option. They are much more efficient that resistors and therefore generate less heat. Link to comment
coolwaters Posted July 24, 2007 Author Share Posted July 24, 2007 well for my circuit i have to use both... like this theres another way to reduce the amps down to 1amp? how??? Link to comment
coolwaters Posted July 25, 2007 Author Share Posted July 25, 2007 is it me or the amps are like 2 to 3 times higher then they say it is....? and dont think i can add anymore LEDs to lower that without blowing up my adaptor... does anyone know how to regulate current without parts overheating? Link to comment
Socalsuperhero Posted July 25, 2007 Share Posted July 25, 2007 is it me or the amps are like 2 to 3 times higher then they say it is....?and dont think i can add anymore LEDs to lower that without blowing up my adaptor... does anyone know how to regulate current without parts overheating? Don't worry about it. Amp is a current rating, the power supply can't "push" current onto the leds, they have to draw current. An led may draw 500ma at 3.5Vf but draw 2A at 4Vf which is why current regulation is so important. Link to comment
coolwaters Posted July 25, 2007 Author Share Posted July 25, 2007 ic...but if i reduce the current to 1amp(forces it to draw a minimum of 1amp) it would last longer? by the way is it possible to use a LM317T regulator without any resistors??? Link to comment
coolwaters Posted July 26, 2007 Author Share Posted July 26, 2007 i think i got it..... so if a power supply is giving of 3.72v (typical voltage) and like 3 amps... the LED will draw only 1 amp since the voltage is 3.72? cuz without the regulator im running the array at around 3.5 and 1.6 amps but the LED is drawing about 450mA of the 1.6amps??? i think i get it now... Link to comment
coolwaters Posted July 26, 2007 Author Share Posted July 26, 2007 it seems that on the 4 series array the first LED is getting 3.6v which is pretty good but the last one is getting only 3v which is pretty bad... none the less the regulator made sure that each LED is getting 1.25amps. anyone know a good LDO regulator at 1amp? Link to comment
Socalsuperhero Posted July 26, 2007 Share Posted July 26, 2007 it seems that on the 4 series array the first LED is getting 3.6v which is pretty good but the last one is getting only 3v which is pretty bad... none the less the regulator made sure that each LED is getting 1.25amps. anyone know a good LDO regulator at 1amp? Almost correct. So the reason your leds are showing different Vf's is because of the small variations in each led. This is what I was talking about before with "bin matching" leds for series use. It's only really important when you don't get a good binning of leds from a supplier and/or are trying to drive the leds within ~10% of their rated maximum. The best way to match leds for series use is to use a current regulator, say 500ma, and hook each led up individually. Then measure the Vf across each led, and sort it according to that number. Then create your series arrays out of leds that either had the same Vf or with others as close to the same Vf as possible. That will ensure that all of your leds are performing very similar and minimize the chance of burning any out. Link to comment
coolwaters Posted July 26, 2007 Author Share Posted July 26, 2007 i dont really want to run one LED parallel... whats a good LDO regulator thats set at 1 amp??? Link to comment
coolwaters Posted July 26, 2007 Author Share Posted July 26, 2007 man think project is looking crazy....theres like 20 wires sticking out... looks like a robot.... anyways i tested it out on my 3g and the lenses isnt a great idea....it has a heaven spotlight effect...its cool tho but not what i had in mine... (growing ricordeas not angels...) i seriously need to clean up this mini array... i just need a better regulator its the onlything getting overheated... next cheap project....2 wal-mart PC bulbs and blue leds as actinics? (just need know how to mount the rebels...dam thos guys r small...) Link to comment
coolwaters Posted July 27, 2007 Author Share Posted July 27, 2007 doesnt anyone think 2 royal blue rebels (the highest bin 525mW) is enough to supplement 2x 20w 6.5k PCs? or even 2x 26w PCs? their pretty bright tho. Link to comment
coolwaters Posted July 27, 2007 Author Share Posted July 27, 2007 been thinking about that....and dont think the 2 leds r going to do anything cuz of the difference in lumens...basically the PCs r going to drown the blue....but i'll give it a test later. Link to comment
NanoClown Posted July 27, 2007 Share Posted July 27, 2007 i dont think 2 will cut try like 4 or so Link to comment
coolwaters Posted July 27, 2007 Author Share Posted July 27, 2007 i guess i'll try 4 if the 2 doesnt workout. but again i dont need it to be like 20k. just a little over 10k is good enough. (no need to be greedy...) Link to comment
Socalsuperhero Posted July 27, 2007 Share Posted July 27, 2007 i guess i'll try 4 if the 2 doesnt workout. but again i dont need it to be like 20k. just a little over 10k is good enough. (no need to be greedy...) how about just getting 10k or 50/50 pc's to begin with? Or a 14k 70w Mh? Link to comment
coolwaters Posted July 27, 2007 Author Share Posted July 27, 2007 dont feel like replacing +$40 bulbs every few months.... i dont know about u but i want to try something different thats one of the reasons i went to saltwater aquariums... and i hate thos overpriced PC bulbs... i have an idea already on the hood. its going to be pretty big tho...about 4" tall =/ Link to comment
coolwaters Posted July 31, 2007 Author Share Posted July 31, 2007 hey just to make sure....if a LED says it draws 700mA at 3volts then if i run it at 3volts it will only draw 700mA? even tho like 3amps are being past through the circuit? Link to comment
Socalsuperhero Posted July 31, 2007 Share Posted July 31, 2007 hey just to make sure....if a LED says it draws 700mA at 3volts then if i run it at 3volts it will only draw 700mA? even tho like 3amps are being past through the circuit? Correct. However as the junction temperature increases, that may change to 900ma at 3v. Link to comment
coolwaters Posted July 31, 2007 Author Share Posted July 31, 2007 ic. guess i'll try to find a better regulator. i have quite a few heatsinks and i'll mount a fan on it so that shouldnt be too much of a problem. i'll try to use one of my old LM317t regulators and wire them in parallel. so that should give each led about 600mA. i mounted the rebel leds....and somewhat wired it. i'll try to get a piece of solder on it to make it easier...its really bright. covered everything in my 10g with just one blue. Link to comment
strangelove Posted July 31, 2007 Share Posted July 31, 2007 i dont think 2 will cut try like 4 or so Hey NanoClown, What is up with the Autobot emblem? not complaining, but I keep seeing it on motorbikes and supped up street racers. See it a lot in Hayward, Fremont, San Leandro, just wondering... Link to comment
coolwaters Posted July 31, 2007 Author Share Posted July 31, 2007 its cuz of Transformers the movie. i saw it and it was pretty good. i just got a great idea (i think) i should wire up a circular fluorescent t5 and put the LEDs in the center. and the fan on top of that so i'll cool down the LED along with the tube. what do u guys think? Link to comment
NanoClown Posted August 1, 2007 Share Posted August 1, 2007 Hey NanoClown, What is up with the Autobot emblem? not complaining, but I keep seeing it on motorbikes and supped up street racers. See it a lot in Hayward, Fremont, San Leandro, just wondering... well me and my cus had it like when the year started, he has one on his 87 Supra, and his 03 kawasaki ninja, i have one on my 84 ford bronco and one on my moms 02 chevy astro then my cus friends really cought onto it and the started to put it on thier cars, so now EVERY1 with a supped up car or bike has it, i dont like good guys the emblem really fits us, and the movie was AWESOME! duh! lol coolwaters sorry for the jack Link to comment
coolwaters Posted August 6, 2007 Author Share Posted August 6, 2007 im really thinking about a hood with a circular CFL on it. the hood design is going to be simple. just a reflector box with clear holders. Link to comment
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