Single COB builds

Humanrob

Humanrob

Well-Known Member
I have a lot of leftover materials from previous builds, including a pair of drivers from my first build. I'm going to be doing some breeding, and need some flexible smaller lights for small spaces. I'm obviously not about making them beautiful, functional is good enough for me. And simple. These take about 45 minutes to build.

Driver: MW LPC-60-1400
COB: Citi 048-1212 (3500)
Heatsink: SST 133 (overkill, but what I had on hand -- the 120 would have been fine)


I'd love to see other peoples single cob builds.

Also, I lucked into a pair of SST- X heatsinks, and I'm wondering if anyone is aware of a driver that would power one Citi 048-1818 at around 90-100watts? I'd love to hang those as single lights also.

single_cob.JPG single_bottom.JPG single_driver.JPG single_rivets.JPG
 
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CobKits

CobKits

Well-Known Member
Humanrob said:
and I'm wondering if anyone is aware of a driver that would power one Citi 048-1818 at around 90-100watts?
Click to expand...
the 80-100W constant current drivers dont go as high as you need on current, constant voltage is what you seek
HLG-100H 54A for sure
HLG-120H-54A for sure

i think a HLG-(100 or 120)-48A will top out at about 80W on voltage,with an 1818 ill look at my data

i think a 54B might top out as well around 80-90

the cost between -100 and -120 series drivers is nominal. id buy a 120 even if youre not going to use the extra wattage right away
 
Humanrob

Humanrob

Well-Known Member
CobKits said:
the 80-100W constant current drivers dont go as high as you need on current, constant voltage is what you seek
HLG-100H 54A for sure
HLG-120H-54A for sure

i think a HLG-(100 or 120)-48A will top out at about 80W on voltage,with an 1818 ill look at my data

i think a 54B might top out as well around 80-90

the cost between -100 and -120 series drivers is nominal. id buy a 120 even if youre not going to use the extra wattage right away
Click to expand...
As you know by now, I still have not wrapped my brain around drivers...

On your website, in regards to how many 1818's the HLG-120H-48A will power you say:
"2 1818@ 78.5W each (157W max) or 3@ 50.7W ea (152W max), 4@ 37.4W ea (150W max), etc."

So what you've just said about he -48A maxing out at 80w (implying, based on the topic, that it would only throw out 80w even with a single 1818 attached to it?), does not make sense to me. I am not doubting that you are correct, just wondering if you could explain how that works?
 
Tim Fox

Tim Fox

Well-Known Member
CobKits said:
the 80-100W constant current drivers dont go as high as you need on current, constant voltage is what you seek
HLG-100H 54A for sure
HLG-120H-54A for sure

i think a HLG-(100 or 120)-48A will top out at about 80W on voltage,with an 1818 ill look at my data

i think a 54B might top out as well around 80-90

the cost between -100 and -120 series drivers is nominal. id buy a 120 even if youre not going to use the extra wattage right away
Click to expand...
Will the Artic 11 pc fan heat sinks handle those 1818's driven at 100 plus watts?

edit : probably a dumb question i know,,
 
CobKits

CobKits

Well-Known Member
Humanrob said:
As you know by now, I still have not wrapped my brain around drivers...

On your website, in regards to how many 1818's the HLG-120H-48A will power you say:
"2 1818@ 78.5W each (157W max) or 3@ 50.7W ea (152W max), 4@ 37.4W ea (150W max), etc."

So what you've just said about he -48A maxing out at 80w (implying, based on the topic, that it would only throw out 80w even with a single 1818 attached to it?), does not make sense to me. I am not doubting that you are correct, just wondering if you could explain how that works?
Click to expand...
great question! i was just guessing without voltage numbers in front of me. im sure a 120 cant drive an 1818 to the drivers full 150W power but couldnt remember exactly where the cutoff is

lets look at the datasheets

1818:

upload_2017-4-9_16-16-7.png

from my bench testing on real heatsinks that looks like this (a little lower as Tc is rarely 25C in practice- the temperature droops voltage a bit):

upload_2017-4-9_16-17-2.png

test report for hlg-10h-48A driver:

upload_2017-4-9_16-18-58.png

so depending on your input voltage, the driver can do 54.24V OR 51.24V (this is news to me- they must have changed the spec, as the drivers i have are older stock as i just put one on the bench and got 54.2V driving an 1818 - from 120V input. if they changed im prob going to stash away my remaining stock for my own use )

so anyway, to keep things simple- lets use 54.2V as the max the driver can put out. in no case can it drive a single 1818 above 2.5A/135W. if youre using one of the newer drivers that can only output 51.24V at 120AC, youd be limited to ~63W per cob
 
CobKits

CobKits

Well-Known Member
xX_BHMC_Xx said:
Running in series, like most DIYers, what's the advantage over CC?
Click to expand...
im not sure if you are asking "what is the advantage to running a CV driver in series like most DIYers" or ""what is the advantage to running a CV driver as opposed to CC in series like most DIYers"

the former is impossible with the chips we use - CVs only really work in parallel unless you have low voltage single diodes or cobs (3-24V)

1.you can add and remove cobs as you please and run them as hard or soft as you like. with a 200W driver i can run 2 cobs at 100W, 3 cobs at 66W, 4 cobs at 50W, 5 cobs at 40W, 6 cobs at 33W, etc. (and dim them all to less as needed)

with a 200W constant current driver you can run 4 cobs at 50W each, 3 cobs at 50W each or 2 cobs at 50W each. in the latter two cases youre utilizing less than 75% and less than 50% of your driver. want to run 5 cobs? too bad- your voltage wont allow it. want to run cobs over 50W? sorry youre limited to 1400 mA

2. makes better utilization of driver. in almost all cases you can get the full 225W output watts out of an HLG185. with constant current drivers depending on your voltage, if its a close match youre lucky to get 200W tops

3. nowhere in the system do you have high DC voltage. its at cob level - 36 or 50V, not 200-400+ with some constant current setups. this makes wiring inherently safer and opens up a wider use of holders such as BJBs which are limited to 150V

"A" drivers have built in voltage adjustment to limit voltage and control thermal runaway. "B" drivers are hard capped at their nameplate voltage (36,42,48,54, etc) and can also prevent thermal runaway when selected carefully to match cob voltage

so in short, there are little to no advantages to constant current drivers. other than thats how people want to do it because they saw it on youtube. In OPs case, there is no constant current driver that is ~100W and delivers 1750+ mA - it just doesnt exist. and with one cob there is no parallel or series to think about.
 
Humanrob

Humanrob

Well-Known Member
CobKits said:
so anyway, to keep things simple- lets use 54.2V as the max the driver can put out. in no case can it drive a single 1818 above 2.5A/135W. if youre using one of the newer drivers that can only output 51.24V at 120AC, youd be limited to ~63W per cob
Click to expand...
OK, let me see if I got this: If I want to run them individually, I can use HLG-120-48A's (from your old stock) and use the internal dimmer to keep them at 90-100w?
 
Rolla J

Rolla J

Well-Known Member
Humanrob said:
I have a lot of leftover materials from previous builds, including a pair of drivers from my first build. I'm going to be doing some breeding, and need some flexible smaller lights for small spaces. I'm obviously not about making them beautiful, functional is good enough for me. And simple. These take about 45 minutes to build.

Driver: MW LPC-60-1400
COB: Citi 048-1212 (3500)
Heatsink: SST 133 (overkill, but what I had on hand -- the 120 would have been fine)


I'd love to see other peoples single cob builds.

Also, I lucked into a pair of SST- X heatsinks, and I'm wondering if anyone is aware of a driver that would power one Citi 048-1818 at around 90-100watts? I'd love to hang those as single lights also.

View attachment 3921769 View attachment 3921766 View attachment 3921768 View attachment 3921767
Click to expand...
Cool idea on your single cob build! Looks fresh
 
CobKits

CobKits

Well-Known Member
Humanrob said:
OK, let me see if I got this: If I want to run them individually, I can use HLG-120-48A's (from your old stock) and use the internal dimmer to keep them at 90-100w?
Click to expand...
yup, you got a voltmeter i assume? how bout a wattsup wall meter?
 
Humanrob

Humanrob

Well-Known Member
CobKits said:
yup, you got a voltmeter i assume? how bout a wattsup wall meter?
Click to expand...
Yeah, I do.

The funny thing is, the more I think about it, the less I like my own idea. I was chasing capacities -- the 1818 + SST-X, how can I maximize that combo? -- but lost sight of the impracticality of having that much light coming from a single source. It's better to spread the love out a bit.

I'm going to stick with the original plan on that one, and run the pair of X's off of the single -48A and have them hum along at 78.5w, nice and cool, no stress no problem.
 
Tim Fox

Tim Fox

Well-Known Member
Humanrob said:
Yeah, I do.

The funny thing is, the more I think about it, the less I like my own idea. I was chasing capacities -- the 1818 + SST-X, how can I maximize that combo? -- but lost sight of the impracticality of having that much light coming from a single source. It's better to spread the love out a bit.

I'm going to stick with the original plan on that one, and run the pair of X's off of the single -48A and have them hum along at 78.5w, nice and cool, no stress no problem.
Click to expand...
brought your head back down from the heavens,, lol
 
Tim Fox

Tim Fox

Well-Known Member
i still like your little single cobs,, great for guys doing perpetuals,, where the heights change across a tent, or very good for auto growers,, who keep a tent on 24,, and move them across, they can be adjusted across the tent
 
visajoe1

visajoe1

Well-Known Member
my veg light. 1212 4k with 36v 1200mah driver on a 140mm heatsink, power cord from my old ballast
IMG_0152.JPG IMG_0157.JPG
happy campers. 7 blades at the 4th node for both on right. the other two ride the genetic short bus
FullSizeRender.jpg
 
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