DIY LED with COBs - small medium and large grows

[h4ppyf4rmer]

Let me ask you a stupid question if I use say a 1400 and a dimmer is that like Deming it down to his 700 I want it to be as efficient as possible when I want and then be able to Blair it also

I think I know what you're saying, if you use a 1400ma mean well supply and you use a dimmer on that supply, you will be cutting down on the current. so if you dim it half way, you are effectively running at 700ma and of course half the wattage the COB will use.

 

[dnewsome2]

I think I know what you're saying, if you use a 1400ma mean well supply and you use a dimmer on that supply, you will be cutting down on the current. so if you dim it half way, you are effectively running at 700ma and of course half the wattage the COB will use.

Right so I'm just trying to understand how they are figuring these efficiency ratios not sure if it's wired in parallel or series or the chip itself or the driver that would make it more efficient.No matter what I want the most efficient and coolest running light set up I can get

 

[h4ppyf4rmer]

Okay so what I would like to accomplish is building this light

Is it possible to build my light so that it will run at its absolute maximum efficiency as far as heat and electric usage but then be able to switch it over when you don't care about heat or electric or efficiency you just want the most light. Would a dimmer simply do that or would I need a separate set of drivers?

the short answer is yes, you would design (COBS and Drivers) for the maximum light that you think you might want. and then dim it down to save on your power usage when you don't need that much light.

efficiency with these COBs are a funny thing, From what @sixstring and @growmau5, the CREE parts are more efficient when driven softer (lower milliamperes), the Vero29 COBs seem to be more efficient when driven harder (more milliapmeres).

 

[dnewsome2]

the short answer is yes, you would design (COBS and Drivers) for the maximum light that you think you might want. and then dim it down to save on your power usage when you don't need that much light.

efficiency with these COBs are a funny thing, From what @sixstring and @growmau5, the CREE parts are more efficient when driven softer (lower milliamperes), the Vero29 COBs seem to be more efficient when driven harder (more milliapmeres).

the short answer is yes, you would design (COBS and Drivers) for the maximum light that you think you might want. and then dim it down to save on your power usage when you don't need that much light.

efficiency with these COBs are a funny thing, From what @sixstring and @growmau5, the CREE parts are more efficient when driven softer (lower milliamperes), the Vero29 COBs seem to be more efficient when driven harder (more milliapmeres).

Okay so once they are fired up you can cut back the voltage? So if your dimmer is turned down and you turn it off they might not turn on unless you turn your dimmer up?

 

[h4ppyf4rmer]

Right so I'm just trying to understand how they are figuring these efficiency ratios not sure if it's wired in parallel or series or the chip itself or the driver that would make it more efficient.No matter what I want the most efficient and coolest running light set up I can get

I would not run these in parallel. You can do it but the downside is if you lose a COB, the current gets split over the remaining COBs which means the remaining COBs get driven harder(brighter). if the remaining COBs hit greater than maximum rated current, you have a cascading failure where the remaining COBs will get ruined. There are definitely ways to get around this issue, but it will take some engineering and more electronic components.

if they are in series, it's like a string of Christmas tree lights, when one goes out, they all go out. then you have to figure out which one went bad, lol

 

[dnewsome2]

I would not run these in parallel. You can do it but the downside is if you lose a COB, the current gets split over the remaining COBs which means the remaining COBs get driven harder(brighter). if the remaining COBs hit greater than maximum rated current, you have a cascading failure where the remaining COBs will get ruined. There are definitely ways to get around this issue, but it will take some engineering and more electronic components.

if they are in series, it's like a string of Christmas tree lights, when one goes out, they all go out. then you have to figure out which one went bad, lol

Understood

 

[h4ppyf4rmer]

Okay so once they are fired up you can cut back the voltage? So if your dimmer is turned down and you turn it off they might not turn on unless you turn your dimmer up?

The dimmer lines on the constant current mean well driver controls the amount of current supplied to all the COBs not the voltage.

 

[dnewsome2]

I would not run these in parallel. You can do it but the downside is if you lose a COB, the current gets split over the remaining COBs which means the remaining COBs get driven harder(brighter). if the remaining COBs hit greater than maximum rated current, you have a cascading failure where the remaining COBs will get ruined. There are definitely ways to get around this issue, but it will take some engineering and more electronic components.

if they are in series, it's like a string of Christmas tree lights, when one goes out, they all go out. then you have to figure out which one went bad, lol

I wouldn't be against investing in fuses or whatever to run them in parallel but I don't know what the benefits are versus series.

 

[h4ppyf4rmer]

I wouldn't be against investing in fuses or whatever to run them in parallel but I don't know what the benefits are versus series.

yeah, I don't know either, never really looked into it.

 

[dnewsome2]

I wouldn't be against investing in fuses or whatever to run them in parallel but I don't know what the benefits are versus series.

So I'll just get a 1400 and some cbx

 

[dnewsome2]

Cxb or whatever the hell they're called

 

[h4ppyf4rmer]

so when you are designing your own lighting COB array, the challenge is to figure out how many COBs the driver you pick out will run.

the Driver specs will give you a voltage range that will give you the constant current of the supply.

I'll do this in series...

lets run through a quick example using an HLG-320H-C-1400 (320 watt, 1400ma constant current) and the CXB3590 36v COB:

each COB needs 36V to light up. to obtain constant current out of your driver, you need a voltage range of 114 to 229 volts

if you put only one COB on this supply, you have only reached 36V and therefore the supply will not give you the constant current and the COB will not light up.

two COBs in series will only give you 72v, they still won't light up.

three COBs in series gives you 108v and I believe they actually will light up because you are close enough.

the maximum amount of COBs for this setup is the maximum voltage of the driver / the forward voltage of the COB. that would be 229 / 36 = 6.36 or 6 COBs

and if that doesn't confuse thing, we're in good shape };-)

 

[sixstring]

this is getting kinda old now but still works good for matching cree and vero cobs to meanwell drivers , @SupraSPL made it for us :cool:

 

[h4ppyf4rmer]

this is getting kinda old now but still works good for matching cree and vero cobs to meanwell drivers , @SupraSPL made it for us :cool:

we should update that by added a few of the newer drivers and adding Luminus and citizen COBs

 

[dnewsome2]

so when you are designing your own lighting COB array, the challenge is to figure out how many COBs the driver you pick out will run.

the Driver specs will give you a voltage range that will give you the constant current of the supply.

I'll do this in series...

lets run through a quick example using an HLG-320H-C-1400 (320 watt, 1400ma constant current) and the CXB3590 36v COB:

each COB needs 36V to light up. to obtain constant current out of your driver, you need a voltage range of 114 to 229 volts

if you put only one COB on this supply, you have only reached 36V and therefore the supply will not give you the constant current and the COB will not light up.

two COBs in series will only give you 72v, they still won't light up.

three COBs in series gives you 108v and I believe they actually will light up because you are close enough.

the maximum amount of COBs for this setup is the maximum voltage of the driver / the forward voltage of the COB. that would be 229 / 36 = 6.36 or 6 COBs

and if that doesn't confuse thing, we're in good shape };-)

so when you are designing your own lighting COB array, the challenge is to figure out how many COBs the driver you pick out will run.

the Driver specs will give you a voltage range that will give you the constant current of the supply.

I'll do this in series...

lets run through a quick example using an HLG-320H-C-1400 (320 watt, 1400ma constant current) and the CXB3590 36v COB:

each COB needs 36V to light up. to obtain constant current out of your driver, you need a voltage range of 114 to 229 volts

if you put only one COB on this supply, you have only reached 36V and therefore the supply will not give you the constant current and the COB will not light up.

two COBs in series will only give you 72v, they still won't light up.

three COBs in series gives you 108v and I believe they actually will light up because you are close enough.

the maximum amount of COBs for this setup is the maximum voltage of the driver / the forward voltage of the COB. that would be 229 / 36 = 6.36 or 6 COBs

and if that doesn't confuse thing, we're in good shape };-)

Thanks for the reply. These cops are a little more confusing then I thought. As I understand it if I run 8 32v soft on a 700 ma that would be my best efficiency. I really only want to build a 2 cob light because of size restriction. I wouldn't be against using four Cobs but I am not sure how close I can stack them together. I definitely plan on using active Cooling. So now I'm thinking maybe I should use 72 v Cobs. Would I still use the same 700ma driver?Either way I am looking for the most efficient set up as possible. I don't think running CPU fans will hurt me that much. If someone would tell me exactly what I need to buy for the setup I would probably blindly follow them. I am thinking I want 3000k Cree but what I really want is the best and most efficient set up.

 

[dnewsome2]

we should update that by added a few of the newer drivers and adding Luminus and citizen COBs

Are you using a small separate driver for each cob in your setup?

 

[h4ppyf4rmer]

Are you using a small separate driver for each cob in your setup?

nope, my 4 x 8 bloom tent will be 18 (six rows of three) Vero29SE 36v 3000K 90CRI cobs running on three HLG-320H-C1400B drivers.

each driver can handle 6 of those COBs.

 

[dnewsome2]

Soon I hope to get some of Logic's GSC X Chemdog D under these COBs

How many watts at the wall should I expect to be pulling running 2 cxa 3070?

 

[Toaster79]

How many watts at the wall should I expect to be pulling running 2 cxa 3070?

Hopefully no more than 150W. CXA is quite outdated.

 

[dnewsome2]

Hopefully no more than 150W. CXA is quite outdated.

I saw there was a lot of new stuff out there. The cxa is still supposed to be pretty good as far as I understand it. I got the 3000k I just couldn't determine how much better off I'd be with a cxb