First build! Rapid LED 3 COB Vero build and review
- Thread starter Cletus clem
- Start date
Jimmyclone42
Well-Known Member
The chips determine the voltage bro.. Thats why there is 36,50,72v chips.. You cannot run a 36v chip at 70v... Boom boom..
Halfandhalf
Well-Known Member
The specsheet does show a max of 40.9v at 2100a and 44v at 4200a on page six of http://www.bridgelux.com/sites/default/files/resource_media/DS33 Vero 29 Array Data Sheet Rev L 20160606.pdf
so that corresponds with your graph. I don't know when you'd see higher side voltages towards the max though honestly.
Oh, I just reread what you wrote. The chip should in fact determine the voltage by the amperage you are running. V=IR the resistance of the cob multiplied by the amperage will give a preset voltage. You can't run it at a higher voltage than that. It will run somewhere between min and max of the 1st graph you linked at that corresponding amperage. Meaning if you are running a 1.4 amp hlg 240h you can't max out the voltage to get higher wattage. There is no way to do that with these vero's that I know of. I have a dimming lead on mine, it adjusts amperage.
so that corresponds with your graph. I don't know when you'd see higher side voltages towards the max though honestly.
Oh, I just reread what you wrote. The chip should in fact determine the voltage by the amperage you are running. V=IR the resistance of the cob multiplied by the amperage will give a preset voltage. You can't run it at a higher voltage than that. It will run somewhere between min and max of the 1st graph you linked at that corresponding amperage. Meaning if you are running a 1.4 amp hlg 240h you can't max out the voltage to get higher wattage. There is no way to do that with these vero's that I know of. I have a dimming lead on mine, it adjusts amperage.
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Jimmyclone42
Well-Known Member
I run 12 vero29 3500/80s and 4 2700/90s over 2 panels.. 90s in the center..What spectrum are you running jimi?
I've been thinking about adding a [email protected],1.4a to my build of [email protected],1.4a replacing the middle cob. That would bring me closer to the max for the driver as well as giving me more red in the spectrum. Lumens might not matter but that coincidentally is only 1000 lumens higher with the 66v chip at 90cri and 3000k. Hopefully I don't burn the plants with more intensity in one cob though when they will all be in the same fixture and height.
Also sorry for the hijack
Heres 1 of them
Heres the wall pull on 2 hlg240-1750s pushing the 8 cobs.. (1 panel)
I dont think its advisable to run different voltage cobs on the same driver..
Mabe @CobKits can advise better on this..
Cheers
Jimmyclone42
Well-Known Member
This is correct, as i stated b4, voltage changes with the current. So at 4200ma you would be pulling 44v but your cob would probably only last a month..
Our constant current drivers regulate the current through the dimmer leads, so when your dimmed right down your probably pulling 34v, when im cranked up mine are closer to 37-37.5v
Halfandhalf
Well-Known Member
Hmm, ya I'd really like to find that out. But I don't see why there would be a problem in series since voltage is entirely independent of each other in that case. As long as I'm under max there shouldn't be a problem. Only problem is if the higher wattage makes the center too intense comparatively but I'd love confirmation.
Jimmyclone42
Well-Known Member
Right on buddy... You got it..
Halfandhalf
Well-Known Member
we need an irc channel for this shit
Jimmyclone42
Well-Known Member
Ive read this a few places, lets see what the cobman says.. Your right in theory it shouldn't matter, but ive read a few threads that said never to mix different voltage chips on the same driver.. Cobkits will have the low down..
CobKits
Well-Known Member
its a non-issue if using a constant current driver in series
I need to look at actual schematics of the drivers the way they work Flys in the face of the way I understand supply voltage. Just never heard of components determining the amount of voltage you get. I thought voltage is always what you make it. Anyways I feel like I was being an asshole now. After pulling my hair out and gettin higher than a giraffes ass I found I was wrong about the 240h1400ma thought for sure I was getting more than that. And the 2100 make will give me 75 watts out of em getting me closer to 500 watts at the cobs. Sucks man really thought I was gettin more than that out of them they are so bright. Guess I'm scrapping this build and starting over. I want as much light as a 4x4 can use. Im gonna get the 2100 ma drivers and add 3 more vero29s. Might just cut up the heatsinks and bolt fans to em so I can spread 9 of them out more evenly in the tent. Suuuuuuuuucks got all my controllers figured out everything else is ready. Now I have to wait for more stuff
Maybe u can explain?
Cletus clem
Well-Known Member
If you go to 2100ma drivers you wont have room to run more cobs. Its very simple. Vf x ma= watts. Vf is determined by drive current though. Current goes up, so does vf. Once vf is achieved, cobs have zero fucks to give about additional volts. Amperage determines intensity and ultimately draw. Driver has a ceiling for both. Hlg-240h-c1400= 89-179v 250.6 w. Hlg-240-c2100=59-119v 249.9w.I need to look at actual schematics of the drivers the way they work Flys in the face of the way I understand supply voltage. Just never heard of components determining the amount of voltage you get. I thought voltage is always what you make it. Anyways I feel like I was being an asshole now. After pulling my hair out and gettin higher than a giraffes ass I found I was wrong about the 240h1400ma thought for sure I was getting more than that. And the 2100 make will give me 75 watts out of em getting me closer to 500 watts at the cobs. Sucks man really thought I was gettin more than that out of them they are so bright. Guess I'm scrapping this build and starting over. I want as much light as a 4x4 can use. Im gonna get the 2100 ma drivers and add 3 more vero29s. Might just cut up the heatsinks and bolt fans to em so I can spread 9 of them out more evenly in the tent. Suuuuuuuuucks got all my controllers figured out everything else is ready. Now I have to wait for more stuff
See thats what i saw and like i said not used to current changing supply voltage. Gotta look up a schematic of a driver so i can understand better. But no I planned on another driver too. So three 2100ma drivers and 9 Vero29s at full blast that should be 675w if I'm right this time lol. I could always use the 1400 for a veg. Would love to have two more 4×4s lol.
CobKits
Well-Known Member
take a look at the voltage/current curve off any datasheet
a diode or cob can only operate on that curve (or close to it given temperature effects)
limit current and voltage doesnt matter
limit voltage and current doesnt matter
Cletus clem
Well-Known Member
Take the voltage forward at the chosen drive current for the cob in question as specified by the manufacturers data sheet and multiply. Then multiply by number of chips in series. If both voltage and wattage are within parameters of chosen driver, you are good.
Example: vf38.7x2100ma=81.3w...x 3 chips=244w 38.7v x 3=116.1v total. All numbers are within capability of hlg-240h-c2100, therefore, cobs light and draw what you just figured they would draw plus what the driver draws. Rapid led kit with 2100 driver draws 260+/-, puts out 243+/- to the chips.
Example: vf38.7x2100ma=81.3w...x 3 chips=244w 38.7v x 3=116.1v total. All numbers are within capability of hlg-240h-c2100, therefore, cobs light and draw what you just figured they would draw plus what the driver draws. Rapid led kit with 2100 driver draws 260+/-, puts out 243+/- to the chips.
Why does that sound familiar? Hey thanks.
nfhiggs
Well-Known Member
You are correct nick. Voltage is the "pushing" force that drives current through the load.
nfhiggs
Well-Known Member
Actually LEDs do not have "resistance" in the conventional sense. They are a non-linear device, meaning their resistance changes as the applied voltage changes. That's why they have a limited operating voltage range.