16 Cob Build- Need Help Please!

[greasey420]

ok here it is, i done fucked up ordering the right drivers and need to know my options. I was hoping for a cob per square foot run at around 50-60w, but like i said i fucked up and need help.

I bought 16 Vero 29 Gen7. 3000k 90 CRI 70V (heatsinks etc.)
I bought 4 of the HLG 240- C- 1400b (89V-179V)

What are my options?
Run 2 cobs per driver, using only 140 of the 170V, is that possible?
Run 4 cobs per driver in a parrallel but series setup, splitting the 1400ma into 700ma per 2 cobs? Work?
Run 3 cobs per driver using 2 of the 70V and add one 36V to the string = 176V of the 179V. Possible?
Buy different drivers and return these to get what im trying to accomplish?
Instead of one giant 4ft by 4ft frame with 16 cobs and using a light track, should i build two of the 8 cobs systems for each side of the 4 by 8 tent?

Need major help and advice, any any input would be greatly appreciated for any and all options. I do need a veg light, maybe keep these drivers for that and get new ones for the flowring cobs? Thank you! Glad to be here too

 

[ChunkySkunky]

Running 2 cobs per driver will be fine, but you won't be pushing the driver as hard as you could. You'll only get 8 cobs working like that,

4 cobs with 2 x 2 in parallel is possible, but probably not too bright. I wouldn't wire like that unless I had an individual fuse for at least each pair of cobs. Efficiency will be high though !


Don't mix 36V and 70V cobs, I suppose it's possible but you'd have to work out how the current would be shared between the cobs, and then how bright they would each be. Headache. Much easier to use all the same cobs.

To get all 16 cobs working you'll need to buy another 4 drivers, or return the drivers you have and get different ones. Not sure which driver you need but I'll go have a look.



EDIT*

HLG-480H-C2100B should work I think, you'd need 4 of them I've never used the Vero's so I'd wait for someone who has to confirm it'll work ;)

 

[greasey420]

Running 2 cobs per driver will be fine, but you won't be pushing the driver as hard as you could. You'll only get 8 cobs working like that,

4 cobs with 2 x 2 in parallel is possible, but probably not too bright. I wouldn't wire like that unless I had an individual fuse for at least each pair of cobs. Efficiency will be high though !


Don't mix 36V and 70V cobs, I suppose it's possible but you'd have to work out how the current would be shared between the cobs, and then how bright they would each be. Headache. Much easier to use all the same cobs.

To get all 16 cobs working you'll need to buy another 4 drivers, or return the drivers you have and get different ones. Not sure which driver you need but I'll go have a look.



EDIT*

HLG-480H-C2100B should work I think, you'd need 4 of them I've never used the Vero's so I'd wait for someone who has to confirm it'll work ;)

Thanks, yes im looking at that driver now, its pricey but only does 229v and 4 cobs i would need 280v? i found this one too the elg240-c-700a and it does 343v so maybe 5 cobs at around 50w, but whats with the 700ma, too low current for the 70v cobs? that driver i mentioned is cheap but it doesnt dim. really appreciate any help and your time, thank you

 

[greasey420]

ok the driver u mentions says constant current 280v but then the specs say 114-229v. this looks like the driver i need but its out of stock. if so pherhaps i choose to just do the 8 cobs with what i got, id be using 140v of the 179v. is this ok? thanks again

 

[1816 House]

Okay, you have 32 sq. ft x 50 watt/ft=1600 watt.
And the 16 COBs need 100 watts each to reach that.
72Vdc COB x 1.4 Amp= 100.8 Watt...you need a 1.4 amp constant current driver .

You can run a 4 x 72Vdc COBs = 288Vdc at 1.4 Amps on this Mean Well driver.
You need 4 of them. Build 4 separate bars, if you want any control over them.
Or just mount the whole rack to the top and leave it there.

HLG-480H-C1400B
Output Voltage (DC) :
171-343V ( 4 x 72Vdc Cobs = 288V)
Max Output Current :
1400mA
Input Voltage (AC) :
90-305VAC
Dimming Signal :
0-10V Analog, 10V PWM, Resistance

Or get the "A" non-dimming version for $10 lesss
HLG-480H-C1400A

 

[greasey420]

Okay, you have 32 sq. ft x 50 watt/ft=1600 watt.
And the 16 COBs need 100 watts each to reach that.
72Vdc COB x 1.4 Amp= 100.8 Watt...you need a 1.4 amp constant current driver .

You can run a 4 x 72Vdc COBs = 288Vdc at 1.4 Amps on this Mean Well driver.
You need 4 of them. Build 4 separate bars, if you want any control over them.
Or just mount the whole rack to the top and leave it there.

HLG-480H-C1400B
Output Voltage (DC) :
171-343V ( 4 x 72Vdc Cobs = 288V)
Max Output Current :
1400mA
Input Voltage (AC) :
90-305VAC
Dimming Signal :
0-10V Analog, 10V PWM, Resistance

Or get the "A" non-dimming version for $10 lesss
HLG-480H-C1400A

Thank you, this is what im looking for, the driver chunky posted is ideal because the voltage almost matches perfect but at 2100ma i believe these veros will run too hot.

Ok i did want ti use my drivers in parrallel series of 2 strings, to get a 700ma current. But, the drivers say 089-179v so i believe these 70v chios would blow up if i did that?

My options are to make two lights now, but is it better to just buy 4 more drivers i already have to power the other 8? it cost 200 or so. Or buy two of the drivers u mentioned which cost another hundred to do that but is there any difference? Using 288v of the 420v per string. Or use 144v of the 179v with the drivers i got and get 4 more.? Thanks i appreciate this

 

[greasey420]

Okay, you have 32 sq. ft x 50 watt/ft=1600 watt.
And the 16 COBs need 100 watts each to reach that.
72Vdc COB x 1.4 Amp= 100.8 Watt...you need a 1.4 amp constant current driver .

You can run a 4 x 72Vdc COBs = 288Vdc at 1.4 Amps on this Mean Well driver.
You need 4 of them. Build 4 separate bars, if you want any control over them.
Or just mount the whole rack to the top and leave it there.

HLG-480H-C1400B
Output Voltage (DC) :
171-343V ( 4 x 72Vdc Cobs = 288V)
Max Output Current :
1400mA
Input Voltage (AC) :
90-305VAC
Dimming Signal :
0-10V Analog, 10V PWM, Resistance

Or get the "A" non-dimming version for $10 lesss
HLG-480H-C1400A

Hey, what about running 6 of the veros on that driver? (68v) because it says it has an open circuit limited of 420v. i would get 80watts per cob? Thanks

 

[ChunkySkunky]

I forgot to type it at the time, but that 2100mA driver I was going to suggest dimming it down to 1800mA (ish)

 

[1816 House]

• You can buy 4 more HLG 240-C-1400b (89V-179V), 800 watts, same as the other side
• You can buy 2 HLG-480H-C1400B (171-343V ), 800 watts
• You can buy 3 HLG-480H-C2100B (114-229V),1350 watts and add a 9 th Cob + heatsink to this combo

Lots of choices. Just get 4 more of the same, keep all circuits the same, light intensity the same.

 

[ChunkySkunky]

Ok i did want ti use my drivers in parrallel series of 2 strings, to get a 700ma current. But, the drivers say 089-179v so i believe these 70v chios would blow up if i did that?

when in series, the voltage is divided across the cobs. Your only option is to run 2 cobs in series (140V)
1 cob would be 70V, so below the 89V minimum. It might work but the driver would not be able to operate in constant current mode. 3 cobs in series would be 210V so outside the maximum voltage the driver can supply.

When in parallel the current is divided. 1 cob would get full current (1400mA), 2 cobs would share the current, so 700mA each.

To run them like that you would wire 2 cobs in series 8 times. Then each driver would run 2 of those strings wired in parallel. It would get you up and running, but I still don't think it would be bright enough.

 

[1816 House]

Hey, what about running 6 of the veros on that driver? (68v) because it says it has an open circuit limited of 420v. i would get 80watts per cob? Thanks

The HLG-480H-C1400B (171-343V ) is 343 max

 

[greasey420]

ok thanks guys! yea when looking at the data sheet for that driver it has a max of 420v, anyhow my biggest concern is efficiency of the power im using so i went with 70v cobs. but not using the drivers full load i lose efficiency? is it that much of a difference? would i have been better going with 36v and using all the voltage a driver has in terms of effciency? Thank you, i may just get 4 more drivers and make another 8 cob light.

Also if i need 50w per sq ft in a 4 by 8. would providing 100w per sq ft on a light mover be the same interms of growth and yield? Thanks, that way i can run two tents instead of one =)

 

[greasey420]

when in series, the voltage is divided across the cobs. Your only option is to run 2 cobs in series (140V)
1 cob would be 70V, so below the 89V minimum. It might work but the driver would not be able to operate in constant current mode. 3 cobs in series would be 210V so outside the maximum voltage the driver can supply.

When in parallel the current is divided. 1 cob would get full current (1400mA), 2 cobs would share the current, so 700mA each.

To run them like that you would wire 2 cobs in series 8 times. Then each driver would run 2 of those strings wired in parallel. It would get you up and running, but I still don't think it would be bright enough.

truly appreciate your input, im learning as i go, thank you chunky!

 

[1816 House]

HLG-480H-C1400B (171-343V )

ok thanks guys! yea when looking at the data sheet for that driver it has a max of 420v...

Output Voltage-Channel 1: 171 V to 343 V
Output Power: 480 W
Input Voltage: 90 VAC to 305 VAC, 127 VDC to 431 VDC

That's the Input Voltage you saw, not the output voltage.
After looking at so many numbers of LEDs and power supplies, they all run together.

Also if i need 50w per sq ft in a 4 by 8. would providing 100w per sq ft on a light mover be the same interms of growth and yield? Thanks, that way i can run two tents instead of one =)

You would be better off to push plants down from a veg box to 800 watt end of tent, to 1350 watt finish. The light mover sounds klunky if you don't have overhead space, like a tent.

 

[greasey420]

ok cool thanks thats def a good idea as monthly perpetual would be nice for once, but hey my drivers are the 250w, but what your saying is when i push 70v to that chip i get roughly 100w at the 1400ma? So altho the drivers are rated, i can only use so much of the wattage? Just wondering when i run it at 100% what ill be pulling at the wall, just got the bolts today to clamp the frame together, oh baby

 

[ChunkySkunky]

P = V x I

72V x 1.4A = 100.8 Watts.

The 70V cobs are actually 2 of the 36V cobs built into 1 cob, so they tend to run around 72V (ish).

The drivers are constant current, so they output 1.4A all the time. The voltage can be anything within the range specified.

So, if you ran 2 cobs in series (144V) @ maximum current (1400mA) then you would be drawing 201.6W from your 250W driver. What that means is you have 48.4W of the driver capacity not being used for anything (almost enough for another cob). This is why you choose a driver which has a spec as close as possible to what you need. Buying more drivers than you need gets expensive, plus I read that they are more efficient when ran as close to their maximum output as possible.

 

[greasey420]

thank you chunkyskunky! when you mean efficient for output do you mean voltage wise or wattage? or both? i built the frame today now i just need wire, is 16ga ok? im having trouble finding 18gauge stranded that rated high voltage.i plan to remote the drivers ten feet away and hopefully get it going tonite or tomorrow, will ad pics, thank you again for helping me understand all this. i realized after i bought the 70vs how hard it is to match them up

 

[ChunkySkunky]

yeah it's much easier to find the right driver with 36V cobs.

16ga wire will be fine, it's just slightly thicker. I chopped up the cord from a broken vacuum cleaner for my wires, it is important you buy wire rated above the maximum voltage you will be using.

You have 2 different efficiencies to worry about with your light.

First is the COB efficiency, the lower the current, the more efficient it is. If you put 100W into the COB, you will get 2 things out, light and (unwanted) heat, 50W of light and 50W of heat means the COB would be 50% efficient. ie. you are using 100W of power to get 50W of light.

The driver efficiency is less of a worry, but the same applies. If you run 200W of COBs on a 200W driver, at the wall the driver might be pulling 220W (the 20W goes to heat in the driver) so the driver is running at 91% efficiency. Just run 1 COB on the same driver, the COB takes 100W, but the driver might pull 120W from the wall, meaning it's only 80% efficient.

Rough made up numbers just to explain the concept.

I like efficiency, I think it appeals to my slightly OCD nature, but it's not for everyone :P

 

[AvidLerner]

You have 70v cobs so to get 50w you need to use hlg-185h-c0700b drivers. 70v x .7a = 49w. The 700ma driver will carry 143 to 286v that is four of your cobs at 200w each driver for a total of 800w 16 cobs four drivers

 

[sixstring]

Dont forget you will need to solder all wire connection on cobs above 250v for safe operation. Push in wire connection have 250v limit