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pop22

Well-Known Member
Current draw is dependent on the driver you use, not the cobs. An HLG320H-48 can run 8 of them at 950ma for 40 watts each

Ok ive got my rig finally put together and will be setting up for flower soon. I have
8 -1818's 3500k cri 90 in a 4x5 area. They are wired in parallel for 50 volts. what would be the recommended current draw for all 8 of them. And what should i expect current draw from the wall to be.
 

vidrose

Active Member
Current draw is dependent on the driver you use, not the cobs. An HLG320H-48 can run 8 of them at 950ma for 40 watts each
Im using an industrial 10 amp power supply with adjustable voltage only, so i was shooting for whats the best efficiency for the leds, since psu could supply 1000 m/a per led with a bit to spare. Please note, the amps are controlled by raise or lowering the voltage in this set up.
 

pop22

Well-Known Member
1.5-2.0 amps then, they are best between 50-100 watts. I have a pair of cobkits active ligh-engines, with 1818 cobs, running at 60 watts each and find them perfect for my needs
Im using an industrial 10 amp power supply with adjustable voltage only, so i was shooting for whats the best efficiency for the leds, since psu could supply 1000 m/a per led with a bit to spare. Please note, the amps are controlled by raise or lowering the voltage in this set up.
 

CobKits

Well-Known Member
Im using an industrial 10 amp power supply with adjustable voltage only, so i was shooting for whats the best efficiency for the leds, since psu could supply 1000 m/a per led with a bit to spare. Please note, the amps are controlled by raise or lowering the voltage in this set up.
id take a look at the efficiency of the power supply, if its less than low 90s in efficiency you might be barking up the wrong tree trying to squeak efficiency out of the cobs themselves only to lose 5% or more to the power supply
 

CobKits

Well-Known Member
^maybe edit that post while you can

test 1: DC watts 293, 293/352 = 83.2% efficiency yuck
test 2: DC watts 409, 409/516 = 79.2% efficiency double yuck

get yourself a meanwell hlg600 its up to 96% efficient
 

vidrose

Active Member
Ok I ran some test, here's some good numbers to look at.

Test 1 50.0 volts dc, 5.86 amp draw with 8-1818 cobs. At the wall 120 volts, 352 watts, 4.4 amps.

Test 2 51.1 volts dc, 8 amp draw with 8-1818 cobs. At the wall 120 volts, 516 watts, 6.29 amps.

psu is rated for 48 volts 10 amps - 220 Volts 3.4 amps It can be dialed up to about 52-53 volts max.

What would be the best to run this at in a 4x5 room.
 

vidrose

Active Member
^maybe edit that post while you can

test 1: DC watts 293, 293/352 = 83.2% efficiency yuck
test 2: DC watts 409, 409/516 = 79.2% efficiency double yuck

get yourself a meanwell hlg600 its up to 96% efficient
Well, it is a first time build with parts on hand, Keep in mind those numbers are at the 120 volts. 120 volt 8.6 amps - 48volt 10 amp dc.
220 Volts 3.4 amps - 48 volts 10 amps It can be dialed up to about 52-53 volts max
Powered at 220 volts should get the efficiency up a bit.
 
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Diskokobaja

Well-Known Member
I know that I read somewhere how xp3 cree will be new groundbreaking thing for led coz they are made for horticulture, vs all now avaible led who are made for lighting.. ;)
 

CobKits

Well-Known Member
thats just hype. theres nothing "groundbreaking" about xp-e chips

we have it pretty good with all the different phosphor white options, and now we have efficient monos to supplement spectra if you want

as far as plant lighting efficiency, increases on the chips are merely incremental. the real gains over time are led and luminaire mfrs decreasing costs thru tech advancements and economics of scale.

if you watched crazydago's growtube last night @Growmau5 discusses this in depth. i fully agree with him that we are on the curve to do something like

2015: only cutting edge DIY hacker builds or super expensive plugins hitting 1.8 umol/J
2016: many DIY builds and a handful of top end plugins hitting 1.8 umol/J
2017: almost all DIY builds and lots of options for commercial fixtures hitting 1.8 umol/J, top shelf DIY and high end fixtures pushing us up to 2.0-2.2 umol/J as the new standard
2018: as costs come down and we get better options for monos, DIYers will be in the 2.5 umol/J range and particularly as consumers become more educated and demand photometrics from their manufacturers, 2.0 umol/J leds will be common all over the place

once we get to that level (were kinda there now absent the shitload of chinese junk out there), it will be the nail in the coffin for HPS. at 2.5 umol/J, 2.0 GPW will be a lot more common than it is today and there will be a lot more people adopting LED- it will be a necessity as margins tighten in the market
 
thats just hype. theres nothing "groundbreaking" about xp-e chips

we have it pretty good with all the different phosphor white options, and now we have efficient monos to supplement spectra if you want

as far as plant lighting efficiency, increases on the chips are merely incremental. the real gains over time are led and luminaire mfrs decreasing costs thru tech advancements and economics of scale.

if you watched crazydago's growtube last night @Growmau5 discusses this in depth. i fully agree with him that we are on the curve to do something like

2015: only cutting edge DIY hacker builds or super expensive plugins hitting 1.8 umol/J
2016: many DIY builds and a handful of top end plugins hitting 1.8 umol/J
2017: almost all DIY builds and lots of options for commercial fixtures hitting 1.8 umol/J, top shelf DIY and high end fixtures pushing us up to 2.0-2.2 umol/J as the new standard
2018: as costs come down and we get better options for monos, DIYers will be in the 2.5 umol/J range and particularly as consumers become more educated and demand photometrics from their manufacturers, 2.0 umol/J leds will be common all over the place

once we get to that level (were kinda there now absent the shitload of chinese junk out there), it will be the nail in the coffin for HPS. at 2.5 umol/J, 2.0 GPW will be a lot more common than it is today and there will be a lot more people adopting LED- it will be a necessity as margins tighten in the market
What kind of cobs i should order for this type of driver?

 
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