LT lurker here, want to pick your brains for specific answer without the trolls and grief? :)

CanadianONE

CanadianONE

Well-Known Member
Sliranax said:
Hmm, well that's unfortunate after you asked that I was actually wondering if it would halve the voltage or double it I knew something had to be wrong in my thinking for you to ask that. And i've read that you shouldn't wire them in parallel which would? do exactly the opposite? halve the voltage and double the current?
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Not sure what you mean by halve. Series you add the Voltage and Current remains constant. Parallel you add the Current and the Voltage remains constant. The advise against parallel because not all COB's will have identical Vf. I have digitized the chart so you can easily see the required voltage in comparison to driver current. Looking at the raw data to the left of the chart. Left column is Current & Right is Voltage

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CanadianONE

CanadianONE

Well-Known Member
So with that said you would need two of these drivers to run the two COB's and you would be able to push them to 2.5A and still get the required voltage. Which would work out to around 135 watts each.
 
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Sliranax

Member
Ok so looking at this, i'm only going to be able to run one of my cobs at 3250ma and 55.32 volts? that's within the range of my driver I think I dont know though if its a trade-off between voltage and current, which is being adjusted current or voltage? as I turn the pot? Youre being extremely helpful by the way I believe with your knowledge and my want to get this done you can convince me of what I need to do :)
 
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CanadianONE

CanadianONE

Well-Known Member
Sliranax said:
Ok so looking at this, i'm only going to be able to run one of my cobs at 3250ma and 55.32 volts? that's within the range of my driver I think I dont know though if its a trade-off between voltage and current, which is being adjusted current or voltage? as I turn the pot? Youre being extremely helpful by the way I believe with your knowledge and my want to get t
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You are adjusting the output current with the pot. With that said @ 3.25a the COB will require 55.32v (25c) The driver is rated for 54v so in this case it could be fine as the driver might supply the extra 1.32v or worst case scenario the driver will automatically lower the output current to match the highest voltage it can supply. The more current output you want the more voltage the driver must supply.
 
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Sliranax

Member
I see, so really i'm in no danger of damaging anything if I just wire in one cob to this driver and turn it up checking the voltage and making sure it stays below 54 volts is what i've gained from this conversation I wish I could figure electricity out I guess its like anything else though you have to want it badly enough and honestly if anyone made a cob light that wasen't outrageously priced I would simply buy it. Also if you dont mind could you tell me what driver it would take to run both of these cobs at say? 80-90%? I can't seem to find anything that will give me 112 volts or so at 11 or so amps?
 
CanadianONE

CanadianONE

Well-Known Member
No you are not in any danger of damaging anything. The driver is a constant current driver. The driver will supply as much voltage that's necessary to keep the current where it should be. As far as what driver to run two of these I would have to have a look never looked into drivers to push that much current. But you do not need a driver that will push 11 amps. I would look for something that could supply 120 volts @ 5 amps. Remember if you are wiring in series then you add the voltage not the current. Each COB @ 5 A will require roughly 58 V (58V x 2 = 116V)
 
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Sliranax

Member
Ahhh I see, ok well i'm gonna dig through some more power supplies and see if I can find one to run both of these cobs I really dont want to buy another small psu like I did this time and end up compromising again, I thank you CanadianONE youve been quite helpful i'll post again if I find a psu I think would run two of them to get youre opinion if you dont mind?
 
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Sliranax

Member
Honestly? i'm kinda leary of you two this kind of thing is still illegal in most places, not the cobs themselves but the usual intended uses for them, but rest assured I have no secret place that any of you couldn't find through a simple google search. With that you shouldn't have any problem finding them I didn't.
 
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Sliranax

Member
Its not about help or not help, its about not having police show up at my door and annoying me :) Wash your hands if you will its irrelevant to me, I would think someone on this site would understand :)
 
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Sliranax

Member
I'll tell ya what though Doc, in the interest of "helping each other out" i'll share a link a sales rep gave me when they didn't have what I wanted in stock try octopart.com it seems to be a metasearch by manufacturer model name across thousands of distributors. Ive never seen it mentioned here.
 
CanadianONE

CanadianONE

Well-Known Member
Sliranax said:
I'll tell ya what though Doc, in the interest of "helping each other out" i'll share a link a sales rep gave me when they didn't have what I wanted in stock try octopart.com it seems to be a metasearch by manufacturer model name across thousands of distributors. Ive never seen it mentioned here.
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Octopart was where I got the link from I posted and was the only one listed for that part number
 
littlejacob

littlejacob

Well-Known Member
Sliranax said:
I'll tell ya what though Doc, in the interest of "helping each other out" i'll share a link a sales rep gave me when they didn't have what I wanted in stock try octopart.com it seems to be a metasearch by manufacturer model name across thousands of distributors. Ive never seen it mentioned here.
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Bonjour
This is illegal for most of us...
How much did you spent on the 2 cobs 2 drivers 2 holders the heatsink and the fan?
And what is the size of your grow room?
Have a great day ★
 
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Sliranax

Member
Here we have a CLU056 4000K with thermal adhesive securing it to a coolermaster 212 evo im going to have to employ a buddy of mine to solder the leads on with my 0 experience and shaky hands theres just no way. If i just pass 12 volts at say 300ma over the + and - leads will it run the fan at full speed? Its a 4 wire pwm controlled fan. LittleJacob i intentionally picked the 4000k due to a graph in the data sheet this was the only bulb that seemed to have both blue and red without much compromise to either or in hopes of eventually having enough of these things running to be able to go all the way through with one light it also had a low cri which from what ive gathered the consensus here seems to agree low cri is better than high cri i trust the crowd you guys already did all the research :) and i thank you for making my life easier
 

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littlejacob

littlejacob

Well-Known Member
Bonjour
It mean 75mA for each fan...a bit low I guess!
Do you know how many mA your fans need?
1A would be better or 500mA mini!
Have a great day ★
 
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