Led Users Unite!

A

astroastro

Active Member
Is anybody out there wondering why it is, when power is much cheaper than LED's, that all these fixtures are not running their '3W' LED dies at 3W? Why not simply up the power of the LED driver and let it fly? The truth of the matter is this, irregardless of what the specifications game is going on in the Cree and Bridgelux specification sheets, irregardless of the marketing claims of the LED fixture makers, the primary power LED die that nearly every one of the companies is making and nearly everyone is using is the 1mm^2, 1W die. When you put this on your aluminum heat sink with a fan and crank 350mA (1W) through it you will be operating the die at temperatures approaching the L70/ 50K lifetime rating of the die. That is the truth. To overdrive them somewhat is certainly possible, but you have to pay close attention to the junction temperature, and you must have a well designed thermal management plan.

Driving these dies at 3x the current density (3W) is virtually impossible in a real world application- unless you simply don't care about the working life of the LED. In that case go ahead and burn them up- you will get about 2x the light out from about 3x the power, and a very short life with greatly accelerated light output degredation.

You cannot accurately get the LED junction temperature from an IR thermometer, and I have had a lot of issues and doubts from the results yielded from a thermal imager, ala FLIR or Fluke. We have a Fluke Ti32 here. I still feel most comfortable with the results I get using the old fashioned calculation based off thermal conductance of the material stack-up between the junction and ambient.
 
A

astroastro

Active Member
I am under the impression that the function of bypass resistors on each LED is based on electricity taking the path of least resistance (LED) until the LED fails (infinite resistance) and then goes through the resistor. The resistor consumes enough power to ensure that the current doesn't increase and overload the rest of the LED's in the series causing cascading failures. I'm no engineer so wondering what is is about this configuration that doesn't work?
Click to expand...
Trust me, believe me- you cannot place a series string of resistors paralleled across a series string of LED's and expect the circuit to operate in the manner in which you are thinking. The resistors will sit there and suck power ALL THE TIME. What is to stop them? The vast majority of small power LED applications, like little indicator lights, etc., use a series resistor to limit current to safe levels (for the LED) and then draw power off whatever source is available- typically the same power supply as the MCU on a PCB, for example. This may be what is confusing you as to the whole resistor thing.

Resistors are not used to either limit current nor as protection/ failure devices in big power LED applications. Current is controlled via a voltage clamped, constant current power supply. To provide protection as described in these recent threads, you cannot use a passive device like a resistor, you need to use an active device with a breakdown voltage similar to but higher than the LED it is trying to protect. In cost sensitive applications this would be a zener diode, in applications where they care about quality, it will be a specialized device.

Try this link if you are interested... http://www.littelfuse.com/what-are-pled-devices-and-how-do-they-compare-to-other-circuit-protection-technologies.html
 
J

jdizzle22

Well-Known Member
dapio said:
jdizzle please explain to me in a little more ignorant terms what it is you've said exactly your saying you can control how much inter nodes appear on the plant? now I am really questioning my knowledge of cannabis and what is petiole and primodium ? im super lost bro
Click to expand...
Sry bro, I thought my LED lights was too powerful for my space (it probably is a bit of a waste of its potential) but I totally forgot I used a bunch of Mykos and Azos (so tons of uber micro organisms + uber LED light = too many nodes because life is too easy for the plant and it barely has to try)
 
J

jdizzle22

Well-Known Member
astroastro said:
Is anybody out there wondering why it is, when power is much cheaper than LED's, that all these fixtures are not running their '3W' LED dies at 3W? Why not simply up the power of the LED driver and let it fly? The truth of the matter is this, irregardless of what the specifications game is going on in the Cree and Bridgelux specification sheets, irregardless of the marketing claims of the LED fixture makers, the primary power LED die that nearly every one of the companies is making and nearly everyone is using is the 1mm^2, 1W die. When you put this on your aluminum heat sink with a fan and crank 350mA (1W) through it you will be operating the die at temperatures approaching the L70/ 50K lifetime rating of the die. That is the truth. To overdrive them somewhat is certainly possible, but you have to pay close attention to the junction temperature, and you must have a well designed thermal management plan.

Driving these dies at 3x the current density (3W) is virtually impossible in a real world application- unless you simply don't care about the working life of the LED. In that case go ahead and burn them up- you will get about 2x the light out from about 3x the power, and a very short life with greatly accelerated light output degredation.

You cannot accurately get the LED junction temperature from an IR thermometer, and I have had a lot of issues and doubts from the results yielded from a thermal imager, ala FLIR or Fluke. We have a Fluke Ti32 here. I still feel most comfortable with the results I get using the old fashioned calculation based off thermal conductance of the material stack-up between the junction and ambient.
Click to expand...
GLH spectra panels run all 3w diodes on average of 2w each now (before it was 1.5w which is what most 3w companies are using now because they only came out in the last few months). You are right in that companies can try to deceive people, and might claim they have 3w diodes that are really 3 1w under the same dome. You can't run any LED at full power because it would burn up very quickly and its actually more efficient at producing light when not run at full power (not more light, but more light for the power).

Yeah I'm really not in the know when it comes to what those are called and how they actually work, I just know there is only maybe 3-4 LED companies that make the effort to make sure their panels don't lose more than 1 LED light at a time (and that when panels have that look on them with these things then we know what they're for).
 
B

budlover909

Active Member
those panels i've loaded up on have the same diodes acros the front so egl has them as well

but quick disassembly shows egl uses lg-led the website written right on the panel bet a quick open up of any of those others might show the same thing that would explain sudden switch everyone movedto a new maker
 
puffenuff

puffenuff

Well-Known Member
jdizzle22 said:
I just know there is only maybe 3-4 LED companies that make the effort to make sure their panels don't lose more than 1 LED light at a time (and that when panels have that look on them with these things then we know what they're for).
Click to expand...
Ive seen yo say this before, but you rarely speak to any other lights besides the spectras...so what other companies are you aware of that use the failsafe design? Thanks
 
J

jdizzle22

Well-Known Member
puffenuff said:
Ive seen yo say this before, but you rarely speak to any other lights besides the spectras...so what other companies are you aware of that use the failsafe design? Thanks
Click to expand...
GLH
Apparrently HTG supply is even doing it now with their 120w models?
http://lgledsolutions.com/
and another one I can't remember the name of and didn't bookmark

I don't talk about lgled because they used 1w and now apparently upgrade to 2w diodes? I only found out today about HTG, and the other one I couldn't remember enough to tell people about. I think its going to go from 2-3 early this year to a dozen or more by 2012

I most commonly speak of Spectra , but I also talk explain why blackstar '240w's may be a better way to go for people. I talk about Spectra because up until the last month or so they had better hardware features (but now everyone moving on up!) and the greatest # of completed LED grows (I read at least 7 or 8). I also talk about blackstar because I think that was the safest way to go besides GLH, and I do explain to people how it can work out better for them depending on their circumstances when they ask about what they should buy.

But now that many LED companies are finally upgrading their aged hardware the difference between them all should be a lot less for a little while, I know the 120w HTG thats been upgraded runs 3w diodes on average of like 1.9something watts (went from a like 100 lights to 50 but still runs 120w, and I'm pretty sure LGLED doesn't use any 3w diodes yet, so I would still say GLH is temporarily best because I doubt HTG is putting the better/best diode brands and at the best wavelength. the 120w HTG is probably the same as the 180w GLH except for the number of diodes and wavelength (on average each diode is a 3w and runs on 1.9 something watts for both)


PS: sorry that probably makes me sound like a fanboy, ok heres how I think it is
I think LGLED may have gone with the special features first, but GLH was the first to go with all 3w diodes (first 1.52w now run 1.92w average, I say average because it can be different for certain wavelengths) and is the only one yet to go 'full spectrum' on these hardware/features (although I'm not sure they refer to it that way, they usually just say 12 spectrum?). Now that people have seen some of the success of GLH and how LGLED got the ball rolling with the better features, everyone is starting to jump switch and try to make a better light. I hadn't heard of anyone else getting involved with this tech and 3w diodes until today with HTG so GLH basically got a 4 month jump on everyone. Now they everyone will start to get on the same page more will try to get a leg up on each other and they will all have more money to do it with since less of their lights are crap).
 
J

jdizzle22

Well-Known Member
JohnSena1noob said:
Mike? Is that you? Jdizzle? Remember me? (TWILIGHT ZONE INTRO MUSIC) :hump:
Click to expand...
This is jdizzle (not mike, I'm in WA mike is in Cali), sorry if I don't remember you (I'm SUPER bad with remembering names). Welcome back to LED Users UNITE! How is your LED light working out for you?
 
Bad Karma

Bad Karma

Well-Known Member
I was just doing my usual Youtube cruising for LED grows.
What I found is the biggest LED grow I've ever seen.
Which is something, because it was originally this growers photos a year and a half ago that sold me on ProSource LED's.
He's greatly expanded his operation since last I saw it, and the upgrades are more then impressive.

Check it out:
[video=youtube;kxPvN9ke2Xg]http://www.youtube.com/watch?v=kxPvN9ke2Xg[/video]
 
B

budlover909

Active Member
lgled is using 3w diodes the panels i have are using those bridgelux ones i mentioned back a few pages
they justaint bein driven at full power
 
mikeandnaomi

mikeandnaomi

Well-Known Member
I am using two 90w LEDS and they are the real deal. The UFO lights helped in creating some killer lush solid white roots. My big question on my next grow is this. 2FT from plant on direct on top. The LEDS don't have the projection of LUMENS like the halides and thus the light is basically straight down.

LEDS thumbs up all the way.
 
J

jdizzle22

Well-Known Member
mikeandnaomi said:
I am using two 90w LEDS and they are the real deal. The UFO lights helped in creating some killer lush solid white roots. My big question on my next grow is this. 2FT from plant on direct on top. The LEDS don't have the projection of LUMENS like the halides and thus the light is basically straight down.

LEDS thumbs up all the way.
Click to expand...
What lens angle do those UFOs use? I assume its either 60 or 120 but I never notice people talk about it. I wonder if companies will be changing their lens angles to be more the same as well...
 
B

budlover909

Active Member

Attachments

J

jdizzle22

Well-Known Member
budlover909 said:
bet thats the same company look at my panel disasembled from egl note writign at bottom

those are 3w NLX-5 or NLX-6 diodes both rated for 3w

get a magnifying glas and check the patter on the top f the diode thats your identifying mark
Click to expand...

Well I dunno dude I'm just going by what that website says and it says 2w even on their newest lights. As far as my personal GLH Spectra 395w 2011 unit, it says "LG.PCB.2.0.2011.1" I don't want to take mine apart*
 
Bad Karma

Bad Karma

Well-Known Member
mikeandnaomi said:
I am using two 90w LEDS and they are the real deal. The UFO lights helped in creating some killer lush solid white roots. My big question on my next grow is this. 2FT from plant on direct on top. The LEDS don't have the projection of LUMENS like the halides and thus the light is basically straight down.

LEDS thumbs up all the way.
Click to expand...
Nice to see some other Sactown residents growing with LED's.
If I'm understanding your question correctly about light heights, it'll take some trial and error.
Start with your lights 2 ft. away (like you mentioned), see how the plants respond at that distance.
Wait a few days, then lower the light to 18" off the canopy, see how the plants respond.
Wash, rinse, repeat until your about 6" off the canopy, I wouldn't take it closer then that though.
If you notice any problems before you get down to 6", hike the light back up to it's previous height.
Take it slow with this grow and your plants will tell you everything you need to know.
Good luck.
 
TshirtNinja

TshirtNinja

Well-Known Member
mikeandnaomi said:
I am using two 90w LEDS and they are the real deal. The UFO lights helped in creating some killer lush solid white roots. My big question on my next grow is this. 2FT from plant on direct on top. The LEDS don't have the projection of LUMENS like the halides and thus the light is basically straight down.

LEDS thumbs up all the way.
Click to expand...
please everyone stop using LUMENS as a tool for measuring anything plant related.......... This has been covered quite a few times that LUMENS don't measure plant related light absorption. LUMENS are for HUMANS!!!
 
B

boneheadbob

Well-Known Member
They say theres no such thing as a dumb question, just dumb people asking questions and in that spirit I offer myself up for sacrafice to a question that has probaly been asked in here before so throw rocks but throw me a bone or two as well.

Will your LED grow finish at the same time as the same seeds being grown under 1000 HDI?
And some say the yields are equal as well as the potency?


Thanks from an newbie Arizona grower with a license to kill,,,,,errr to grow.
 
maxpesh

maxpesh

Active Member
Hi there just wondered if anyone using maximum flowering spectrum led models has experienced faster flowering times compared to using HPS as I am growing great white shark under 2 x 500watt blackstar flowering models for the first time and they seem to be about 2 weeks ahead of schedule, I have been growing for years under HPS but like I said, never LED before, thanks in advance for any advise :-)
 
You must log in or register to reply here.
Top