Want to build a budget LED/COB for my 4x4
- Thread starter Desmondg
- Start date
Barristan Whitebeard
Well-Known Member
Are you using the A, B, or AB version of the HLG-320H-42 ?
XtraGood
Well-Known Member
A, but I think any should work, one might be slightly more efficient when dimmed I'm not sure. The drivers themselves are within about $5 of each other, I almost went with ab this round but I pretty much end up running the drivers mostly maxed on 235v ac and adjusting height so just went with A's again.
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cobshopgrow
Well-Known Member
if you distribute them well and be able to hang them low you can save a bit.
for my part i am quite astonished what could be done with about 200W in a 3x3 at about 800ppfd (even bigger 3.28x3.2
.
dont take this numbers as theyre in stone.
a lil reserve is always good to have especially if you have co2 nd high temps, but with a modern setup this 30w rule should do you well and get you in the 1000ppfd plus teritorry.
for my part i am quite astonished what could be done with about 200W in a 3x3 at about 800ppfd (even bigger 3.28x3.2
.dont take this numbers as theyre in stone.
a lil reserve is always good to have especially if you have co2 nd high temps, but with a modern setup this 30w rule should do you well and get you in the 1000ppfd plus teritorry.
Actually for fun. Lets do both and see where it takes us.@4ftRoots I’m not sure if I get them at 30w max or figure 50w max but dim them down? This is where I was kind of hoping you experienced guys would help me make the right decision.
Ok we have step 1 and 2 covered.
Step 1:
LED: Eb Gen 3 strip
From the datasheet here: https://www.bridgelux.com/sites/default/files/resource_media/DS132 Bridgelux EB Series Gen3 Data Sheet 20190617 Rev A.pdf
Forward voltage of a single strip is 19.1 at 700mA. 20.2 at 1400mA
Let do some building.
You want to build 2x2 fixtures in two instances.
Step 2)
30w per sqft:
Total power: 30w x 4 sqft = 120 watts
50w per sqft:
Total power: 50w x 4 sqft = 200 watts
Step 3)
Lets find a HLG driver here: https://www.ledsupply.com/led-drivers/mean-well-hlg-c
30w per sqft:
The HLG 120 seems to fit here.
50w per sqft:
the HLG 240 is a little high but would work here. (60w instead of 50w)
Step 4)
Lets look at that datasheets and pull some info. I assume you want to run without a heatsink and use a reasonable amount of strips. So lets run at 1050mA (max current without heatsink)
Lets assume a strip voltage at 1050mA of 19.6ish. Eh why not. In the middle of the above numbers.
30w per sqft:
Datasheet: https://www.meanwell.com/Upload/PDF/HLG-120H-C/HLG-120H-C-SPEC.PDF
CC region voltage at 1050mA: 74 - 148v
Min LEDS = 74/ 19.6 = 3.7 so 4 minimum
Max LEDS = 148/ 19.6 = 7.5 so 7 max
(Round up for min and down for max. Stays within spec)
50w per sqft:
Datasheet: https://www.meanwell.com/Upload/PDF/HLG-240H-C/HLG-240H-C-SPEC.PDF
CC region voltage at 1050mA: 119 - 238v
Min LEDS = 119/ 19.6 = 6.07 so 7 minimum
Max LEDS = 238/ 19.6 = 12.1 so 12 max
(Round up for min and down for max. Stays within spec)
Step 5)
Lets design.
I'll let you do that. But lets look at the prices of the drivers and see if that guides us.
HLG-240h-1050b - https://www.mouser.com/ProductDetail/MEAN-WELL/HLG-240H-C1050B?qs=EaAZLd8vSkhdBhJosvNDdg==
64 bucks a piece
HLG-120h-1050b - https://www.mouser.com/ProductDetail/MEAN-WELL/HLG-120H-C1050B?qs=%2BmCJZPMmHFM3geOPLGRO6Q==
48 bucks a piece
personally, 16 bucks is not a huge deal for me so I would go with the higher power driver. I can also run more LEDs so I can a better spread.
Hope that helped sir
Desmondg
Active Member
I have 80” from top to bottom inside to play with so whatever you think would be best. I will make the panels adjustable up and down.
XtraGood
Well-Known Member
I run each two ft gen2 strip around 20watts or less, (measured at the wall and divided by # strips, so slightly better efficiency than that 17, 18, 19 watts?). I had tuned the drivers to a case temp before switching to 235v which dropped my case temps, now even run full out they're cool enough to hold onto with my hand. Exposed back side of strips also run pretty cool, safe to touch. Keep the lights about 2ft from main canopy, aiming for 50-60k lux on a dr. meter.
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Desmondg
Active Member
@4ftRoots you are a machine! Thanks a bunch. I will do some digging and see what I can find for part numbers etc on the strips from Digikey and report back with my shopping list to make sure I get everything I need. Then I will build one and see how it goes and show you all what I did. Again thanks soooooo much for your help. This forum rocks!
welight
Well-Known Member
The plan I gave you the link for was based on 37.4 watts/sf but you can off course dim them downThanks @welight fir those plans. Useful for sure. I am going to go with (I hope) 2x2 lights. Plan to use 1x1 aluminum tubing for all the frame work as well as heat sinks. I would like to use a combination of 3500k and 5000k within each light. I will make all 4 lights the same which will make things easier for me to order. Plan is to have 30watts / sf with these lights. Would this be doable? I read that it is better to have more strips at lower wattage than it is to have them maxed out right?
I hope this helps with what I want to do, I just don’t know if it will work or not. And what driver to get for each panel?
Thanks again for your help everyone
Cheers
XtraGood
Well-Known Member
One thing I've noticed is that HLG-185H's of whatever variety are also at one of the best price points for the watts for the smaller drivers. And the reports for them have them going above rating further than most. The 240h and 320h are at good Watt/$ too.
The HLG-185H-20A on Mouser is $51.28 and the HLG-185H-1050B is $52.66.
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