Matching Drivers and COBs

[Greengenes707]

@Shredderthirty
The 80-48 will run one of any of the 36ishV bigger cobs(vero29, cxb or cxa 3070, 3590) fine. Potential is wasted, but it is totally functional(~1.7a). And since there is extra voltage on it, you might get it outputting closer to 1.9a.

The 12v is interesting. Definitely more advanced thinking necessary. Multiple parallel strings. Could go white like MKR's or put together a red supplemental light.

 

[SaltyNuts]

Knowing full well that my knowledge of COB LED systems and drivers will likely never approach that of many people already here, I freely confess to cheating- cribbing the designs broadly acknowledged here to be best in class and slavishly aping them! I don't need to be the expert at everything, juuuuust at my thing...

yeah, using the forums is kind of a challenging way to learn both the principles and the applications, but it is easier and faster than getting a degree in advanced electronics!

 

[speedyganga]

Hi,
I am interested in the HLG 240H 36A/B
But I can't figure out how it work,
On vero 29 it would make them run at 36V isn't it ? so about 30W each,
How can you dimm it down or up if it is constant voltage ?
Does it mean all my COB in // could receive less curent and hence decrease their voltage at some point, down to 34V for example ?
In this case what will happen to the 2V missing for the driver ?

 

[mlabit]

Hi,

someone can say me at which current 4 Vero29 (serie) will work with 1 HLG-185H-C1400B ? And If it's a good idea to do that ?

Thanks

 

[phyloo]

Hello everyone,

speedyganga : you have to wire your COB in parallel, to avoid voltage division due to serial connexion.
The driver you talk about can both handle constant current and constant voltage output but we actually use it more like a constant current version.

You can adjust output current from 3.3 to 6.7 amps, so if you put 4 vero 29 in parallel, they'll have from 3.3/4 = 825mA to 6.7/4 = 1675mA each (but as the driver can provide 240W max, you'll have more like 1.5 amps max each).
According to bridgelux datasheet and my own measurements -and as COB will impose output voltage- the driver will be asked to deliver from 36.4V to 38V for this range of current (he can actually provide up to 38.5V)

So you can expect from 30W to 60W for each COB, depending on the current adjustement you did on the driver...basically from 120W to 240W (maximum output) of global power for 4 vero 29.


mlabit : a HLG 185H c 1400 can't handle 4 vero 29, as output voltage is limited to 143V.

Depending on environment and current output the more you can provide is 143/4 = 35.75V for each ; this voltage is tipically the one needed @675/700mA.
The driver won't be able to provide more voltage, so the max power will be something like 25W for each COB, when only 3 vero 29 wired in series will provide 50W @ 1400mA under 37V each...

I can tell because I've tried this with 4 vero29 on a HLG 185H 1400A, voltmeter + ampmeter and the current does not even raise 700mA for 143.3V... dimming internal potentiometer has absolutely any effect, the driver is at maximum voltage range and just can't provide more volts... so the COB just can't have more amps !

Wiring 3 vero 29 is OK with this driver and adjustment can be done from 25W to 50W each.

See ya folks !

 

[Greengenes707]

With 4 veros or cxa's in parallel use the hlg240-42 and they'll run ~1.3a. For cxb's the hlg240-36 works great and get you 1.650.

With 4 cxa's on an hlg185h-c1400 it drops the current down in the 900ma and was hard capped at 143.2v for mine. Same or similar will happen with the vero. I'm nbelive supra has tried to get over 143v and couldn't either.

 

[Shredderthirty]

@Shredderthirty
The 80-48 will run one of any of the 36ishV bigger cobs(vero29, cxb or cxa 3070, 3590) fine. Potential is wasted, but it is totally functional(~1.7a). And since there is extra voltage on it, you might get it outputting closer to 1.9a.

The 12v is interesting. Definitely more advanced thinking necessary. Multiple parallel strings. Could go white like MKR's or put together a red supplemental light.

cool cool i may get one 65K 3590 and use it for a lil veg light ( i was hoping i could run 2 CXB on this driver, do you think that is possible at all with all the adjustments?)

very interesting on the multiple parallel strings, i may look into something like that

 

[Greengenes707]

cool cool i may get one 65K 3590 and use it for a lil veg light ( i was hoping i could run 2 CXB on this driver, do you think that is possible at all with all the adjustments?)

very interesting on the multiple parallel strings, i may look into something like that

You could run 2 in parallel...~30w each
Or
1 at ~60w

I would just run one myself.

 

[bassman999]

Hello everyone,

speedyganga : you have to wire your COB in parallel, to avoid voltage division due to serial connexion.
The driver you talk about can both handle constant current and constant voltage output but we actually use it more like a constant current version.

You can adjust output current from 3.3 to 6.7 amps, so if you put 4 vero 29 in parallel, they'll have from 3.3/4 = 825mA to 6.7/4 = 1675mA each (but as the driver can provide 240W max, you'll have more like 1.5 amps max each).
According to bridgelux datasheet and my own measurements -and as COB will impose output voltage- the driver will be asked to deliver from 36.4V to 38V for this range of current (he can actually provide up to 38.5V)

So you can expect from 30W to 60W for each COB, depending on the current adjustement you did on the driver...basically from 120W to 240W (maximum output) of global power for 4 vero 29.


mlabit : a HLG 185H c 1400 can't handle 4 vero 29, as output voltage is limited to 143V.

Depending on environment and current output the more you can provide is 143/4 = 35.75V for each ; this voltage is tipically the one needed @675/700mA.
The driver won't be able to provide more voltage, so the max power will be something like 25W for each COB, when only 3 vero 29 wired in series will provide 50W @ 1400mA under 37V each...

I can tell because I've tried this with 4 vero29 on a HLG 185H 1400A, voltmeter + ampmeter and the current does not even raise 700mA for 143.3V... dimming internal potentiometer has absolutely any effect, the driver is at maximum voltage range and just can't provide more volts... so the COB just can't have more amps !

Wiring 3 vero 29 is OK with this driver and adjustment can be done from 25W to 50W each.

See ya folks !

Thanks for this first hand info on this setup!
I ended up buying the hlg240-42 and it is on its way with my CXAs

 

[bassman999]

With 4 veros or cxa's in parallel use the hlg240-42 and they'll run ~1.3a. For cxb's the hlg240-36 works great and get you 1.650.

With 4 cxa's on an hlg185h-c1400 it drops the current down in the 900ma and was hard capped at 143.2v for mine. Same or similar will happen with the vero. I'm nbelive supra has tried to get over 143v and couldn't either.
View attachment 3540358 View attachment 3540360

The CXA and VERO 29 wouldnt be a good match for the hlg240-36?
I bought the hlg240-42 because I got a great deal on it, but was worried about getting less power to the cobs honestly.
I read that the hlg240-36 was adjustable to 38.5V, but was worried about buying it to try it myself if it might end up in low current protection mode.

 

[Shredderthirty]

You could run 2 in parallel...~30w each
Or
1 at ~60w

I would just run one myself.

yeah i was just hoping to lite up a bigger spot than a 2'x2'.... well how much space do you think it will light up?

 

[bassman999]

I have a question, on a MW driver (B) series do you need to use a pot or voltage source, or can you short them together or cap them off.
What I am saying is I dont have pot, and want to test my light.

 

[Positivity]

I have a question, on a MW driver (B) series do you need to use a pot or voltage source, or can you short them together or cap them off.
What I am saying is I dont have pot, and want to test my light.

just leave the wires unconnected and you'll get full power. Wouldn't short the wires on purpose, you may damage the circuit. cap off...

 

[Greengenes707]

I have a question, on a MW driver (B) series do you need to use a pot or voltage source, or can you short them together or cap them off.
What I am saying is I don't have pot, and want to test my light.

Don't short them. Cap them with some tape or connectors. When the dimming circuit is left open it will give full power...and possibly a few percent higher(108% per the data sheet).


I've never had one give me an extra 8%. But 1440-1460ma isn't uncommon.

 

[bassman999]

just leave the wires unconnected and you'll get full power. Wouldn't short the wires on purpose, you may damage the circuit. cap off...

Don't short them. Cap them with some tape or connectors. When the dimming circuit is left open it will give full power...and possibly a few percent higher(108% per the data sheet).
View attachment 3547705

I've never had one give me an extra 8%. But 1440-1460ma isn't uncommon.

Thanks guys!
I was almost certain that was the way to go, just needed validation.

I saw that 100-108% written there on the spec sheet and didnt now what make of it.

 

[bassman999]

I have another question about cobs.
I am running my (6) CXA3070s on a HLG-240H-42B
I measured the Vf and it was 35.6V
So the question is is Vf increase with current draw?
I have read that Vf on the CXA is 38.5.

 

[EfficientWatt]

A : Yes, it does.

Also, Vf (and efficiency) increase with lower operating temps. (see below)

Have you aquired sufficient knowledge to be able to decrypt the sacred texts ?
CXB3070 : http://www.cree.com/~/media/Files/Cree/LED Components and Modules/XLamp/Data and Binning/ds CXB3070.pdf
CXA3070 : http://www.cree.com/~/media/Files/Cree/LED Components and Modules/XLamp/Data and Binning/ds CXA3070.pdf

Following is for cxb3070 :

I have another question about cobs.
I am running my (6) CXA3070s on a HLG-240H-42B
I measured the Vf and it was 35.6V
So the question is is Vf increase with current draw?
I have read that Vf on the CXA is 38.5.

 

[ttystikk]

A : Yes, it does.

Also, Vf (and efficiency) increase with lower operating temps. (see below)

Have you aquired sufficient knowledge to be able to decrypt the sacred texts ?
CXB3070 : http://www.cree.com/~/media/Files/Cree/LED Components and Modules/XLamp/Data and Binning/ds CXB3070.pdf
CXA3070 : http://www.cree.com/~/media/Files/Cree/LED Components and Modules/XLamp/Data and Binning/ds CXA3070.pdf

Following is for cxb3070 :
View attachment 3548299

That would be a negative, ghost rider... so I just cribbed a combo y'all said was good, LOL

 

[bassman999]

I see
Temperature increase is proportional to decrease in Vf whereas IF increase raises Vf.

If I am measuring 35.6V, I might not be cooling well.
I was measuring Vf with passive cooling in ambient 71*F, and IF of 950mA

 

[alesh]

I see
Temperature increase is proportional to decrease in Vf whereas IF increase raises Vf.

If I am measuring 35.6V, I might not be cooling well.
I was measuring Vf with passive cooling in ambient 71*F, and IF of 950mA

Well, actually higher Vf causes higher current to flow through but yes

35.6V is expected value for your setup. Nothing's wrong.