# My Plan For A Cree Cxb3590 Light Bar

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#### seaslug

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Sea, When iwas trying to calculate the efficiency of the driver i simply added the vf of the pair of 72v cobs and approximated that i was around 90% efficient. Im wondering if my math makes no sense at all. I was using the attached graph.

I think you're only doing the first step. Say there is 144Vf total on our string of LEDs. How do you read the Mean Well efficiency chart? We need to know what the fraction of total power is, expressed as a percentage of total allowable load. The maximum (constant current region) voltage for the HLG-120H-C700 is 215V. In this example, the load would be 144V / 215V = 67% Looking at the chart you provided, this puts the driver efficiency at just over 92%.

#### REALSTYLES

I think you're only doing the first step. Say there is 144Vf total on our string of LEDs. How do you read the Mean Well efficiency chart? We need to know what the fraction of total power is, expressed as a percentage of total allowable load. The maximum (constant current region) voltage for the HLG-120H-C700 is 215V. In this example, the load would be 144V / 215V = 67% Looking at the chart you provided, this puts the driver efficiency at just over 92%.
View attachment 529023
Just be careful with the 350ma and 500ma because they can kill you if you get shocked.

Edit: because of the high voltage

#### testiclees

I think you're only doing the first step. Say there is 144Vf total on our string of LEDs. How do you read the Mean Well efficiency chart? We need to know what the fraction of total power is, expressed as a percentage of total allowable load. The maximum (constant current region) voltage for the HLG-120H-C700 is 215V. In this example, the load would be 144V / 215V = 67% Looking at the chart you provided, this puts the driver efficiency at just over 92%.
View attachment 529023

ok thank you.

i was coming up with pretty much the same %. In real time application the driver and cobs seem to be an excellent addition and they are barely raising the room temp... although canopy temp is a lil warmer.

#### seaslug

Sprained my back (again) but came up with a better veg bar design; this uses the wider profile of 4.230 inches.

HeatsinkUSA.com purchases over \$100 are 10% off this month, code GIVEME10.

I recently found out about verical.com, Arrow's surplus site. Most items have biggish minimum purchase quantities but I was able to get three CXA3590 5000K 36V CD flux bin (ANSI white code part number) and 14 holders at a good price.

#### seaslug

The plan now is two 72V 3000K CXB3590 with a 36V 4000K CXB3070 in the middle, driven by HLG-185H-C1050A. I was going to use 5000K in the middle but I bought some efficient 4000K from Cutter in Australia (discount code CUTANDROLL). Shining a blue spike in the middle of each plant but I really don't care about trichs--I don't sell and I don't make pollen hash.

I've been undecided where I'll be living--looks like I'll get back to gardening now. :)

#### 5ecret 5quirrel

The plan now is two 72V 3000K CXB3590 with a 36V 4000K CXB3070 in the middle, driven by HLG-185H-C1050A. I was going to use 5000K in the middle but I bought some efficient 4000K from Cutter in Australia (discount code CUTANDROLL). Shining a blue spike in the middle of each plant but I really don't care about trichs--I don't sell and I don't make pollen hash.

I've been undecided where I'll be living--looks like I'll get back to gardening now. :)
i've been reading conflicting articles about supplementing UV lighting . . . to UV or not to UV?

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would a 4.6" x 4" of the serrated fin be as good passively as 3.5" x 32"? was wanting to try 1.8" x 40", using 3 luna 100 3500k flip chip opto powered by M. W. hlg-240h-c1400a, spacing them 20" apart from the middle and 10" from the Edge. enclose in polycarbonate fixture, with one fan on each end. which would cool better any ideas?​

#### seaslug

I don't see the need for UV if the blue spectrum is strong like my Lumigrows.

About the heatsinks, please2waze, are you putting a fan on the 4.6 x 4"? It would cool better than the 3.5" of whatever length.

The 1.8" wide profile I'm not too sure about, that width is good for small diodes and stars more than COBs I would think. The Luna 100 is 1.5 inches square.

D

#### Dvsmith

Hey, any of you guys from Detroit area? Met this dude last night at a show and he was a fellow grower telling me to research these leds. But I didn't get his number and wanted to learn more about them Hoping he might be on forums.

#### AvidLerner

i've been reading conflicting articles about supplementing UV lighting . . . to UV or not to UV?
UVB 290nm-310nmn is a very narrow bandwidth Thee are plenty of LED's that address UVA/UVC but not UVB directly. UVB is suntan rays, or sunburn rays. UVA/UVC kills bacteria, blue light. There are no/few LED's out there that meet that narrow bandwidth frequency. but there is a fluorescent light for reptiles that is a 48" unit costing about \$30 each tube for a two tube fixture. One tube is adequate for 10 SF area. peace

#### keiksweat

I use uvb reptile lights supp,I swear by the resin content.defo makes difference

#### AvidLerner

would a 4.6" x 4" of the serrated fin be as good passively as 3.5" x 32"? was wanting to try 1.8" x 40", using 3 luna 100 3500k flip chip opto powered by M. W. hlg-240h-c1400a, spacing them 20" apart from the middle and 10" from the Edge. enclose in polycarbonate fixture, with one fan on each end. which would cool better any ideas?​
I would go with a 5.66 x 18" with a 1400mm fan active cooling. Passive cooling would be closer to 36" same profile. Peace

#### 5ecret 5quirrel

i just burned my plants with cob lights . . . again : (

#### Toaster79

i just burned my plants with cob lights . . . again : (

Ditch those reflectors ;)

#### keiksweat

i just burned my plants with cob lights . . . again : (
what lights you burning with....pics mate.how close to canopy you got em?if I get my panels too close by an inch or two ,I get burn or dis coloured leaves.two weeks later after thinking I got lock out.then the burning tops become clear.nightmare.

#### 5ecret 5quirrel

what lights you burning with....pics mate.how close to canopy you got em?if I get my panels too close by an inch or two ,I get burn or dis coloured leaves.two weeks later after thinking I got lock out.then the burning tops become clear.nightmare.

i'll send pics later, about 36" off the canopy, i had the same problem you did thought they need food but they were burning! and burning at all the new growth spots, older leaves not so bad.

absolute worse time to burn them is weeks 1-3 of flowering, it will destroy your harvest. at this point i don't turn lights to 100% until week 4, any thoughts?