DiY LED - Cree CXA3070

S

speedyganga

Well-Known Member
Hey I was wondering, for people who use cxa3070 do you have one chip per square foot ?
at 35% efficiency and more I would think that 30W per sqf would be ok
At least the maximum under hps I was doing is 60W/sqf (250W in 2x2) and I felt I was wasting power as I harvest much less than in a 3x2 room. 40W per sqfoot is better in term of efficiency according to me.
I have the feeling we are a bit going in a weapon race.
Or maybe it is just because the cob of more than 30W push a lot of light but not on a broad area...

I wonder this because I am going to put 200W of vero in a 0,4m2 I find it a bit overkill at the end. In this space I would put a 150W for the best gr/W efficiency and go up to 250W if I wanted better result. Then 200W of led seems in fact a lot.
Well anyway more light is never an issue. But I guess there is no point choosing the most effectient light if at the end you don't give it the maximum space to achieve a an efficient harvest.
I don't know if what I am saying make sense ^^
 
Positivity

Positivity

Well-Known Member
My theory is build a light on the upper end of the intensity scale..50-60w sq/ft...and use dimmers to bring it down to efficient range.

You get to use the led for what's its capable..to see what is capable..then dim it down to an efficient level if that's the goal.

You may decide the efficient level is tits or maybe the extra power gives the buds you like...options..flexibility..

Unless a large space/grow...then efficiency is king..not to mention light overlap
 
SomeGuy

SomeGuy

Well-Known Member
Hey supra,

Thanks for posting all this great info. It is much appreciated.



I was wondering if you thought this would work as a combo.

12x: http://www.fasttech.com/products/1612/10004218/1320600

12x: http://www.digikey.com/product-search/en?mpart=BXRC-30H4000-F-03&vendor=976

I would be making 4 fixtures with 3 cobs each actively cooling each cob. I am cool with soldering etc... My questions are:

-the driver runs 1.3amp as per your review. What would the wattage of each COB be in this setup? at 1.4amp I believe the data sheet says 42.3amps...

-Any ideas for encasing the drivers? mounted in a small pc case and fan cooled maybe?

-what about UPC panel mount and pass through source? (for daisy chaining?)

-What gauge wire do you recommend? I want to remote mount the drivers outside the tent and do not want extra heat/resistance to impede performance.


Thanks again!

SG
 
Observe & Report

Observe & Report

Well-Known Member
The Driver Selection Voltages section of the Vero 18 datasheet has 25.2V-33.5V @ 1.4A. I'm sure you won't let Tc get that high but it also won't be -40C so maybe Vf might dip below 30V?? What's the real constant current range of that driver? 30-36V seems narrow.
 
R

Rooster99

Well-Known Member
SomeGuy said:
Hey supra,

Thanks for posting all this great info. It is much appreciated.



I was wondering if you thought this would work as a combo.

12x: http://www.fasttech.com/products/1612/10004218/1320600

12x: http://www.digikey.com/product-search/en?mpart=BXRC-30H4000-F-03&vendor=976

I would be making 4 fixtures with 3 cobs each actively cooling each cob. I am cool with soldering etc... My questions are:

-the driver runs 1.3amp as per your review. What would the wattage of each COB be in this setup? at 1.4amp I believe the data sheet says 42.3amps...

-Any ideas for encasing the drivers? mounted in a small pc case and fan cooled maybe?

-what about UPC panel mount and pass through source? (for daisy chaining?)

-What gauge wire do you recommend? I want to remote mount the drivers outside the tent and do not want extra heat/resistance to impede performance.


Thanks again!

SG
Click to expand...
Thats pretty much the setup I have been running for a little while now. 4 x Z2 CXA 3070's and one of those fastech drivers per COB. Works well. Although, there is an ebay link for a driver Supra reccomended that were more efficient and actually did output the full 50w for pretty much the same price. I think these fastech drivers are not as accurate and is not outputting the full 50w. Either way, with 4 cobs, 4 fastech drivers, 4 cpu/heatsink combos and a sheet of aluminium to mount it all on. Cannot complain. Works like a champ. I'd say go for it (but I really would reccomend the units from ebay as they also have a ground connection which the fastech drivers do not have).

Good luck!
 
SupraSPL

SupraSPL

Well-Known Member
speedyganga said:
Hey I was wondering, for people who use cxa3070 do you have one chip per square foot ?
But I guess there is no point choosing the most effectient light if at the end you don't give it the maximum space to achieve a an efficient harvest.
Click to expand...
I agree, this is a very important point. Some growers are looking for a massive light blast without the heat of 1000 HPS. For them we can dissipate up to 50W/ sq ft. (39% efficient lamp) But for those looking for max efficiency we can use about 25-35W/ sq ft with lamps that range from 36-49% efficiency and get great nugs. (Z2 at 1.4A is 36% and AB at 700mA is 49%.)
 
SupraSPL

SupraSPL

Well-Known Member
Java, I love that driver but I am having a problem with the seller. They sent me a shipment of drivers that are slightly longer than the original I tested. These new drivers were defective. Vf range only goes up to 25, they only put out 700mA @ 37vF and the operate at 83% efficient. To be honest I am angry at the seller. Normally I just eat it when I get a dud, but I felt tricked in this case and it was a whole batch so I pursued a refund. They made me return the drivers to China at my cost to prove my complaint, despite photos of the multimeters and I have been working with them for over a month to try and get (half) my money back. Hopefully other DIYers dont get anything from that defective batch.
B.jpg

This driver on the other hand, has been performing great, puts out over 1400mA and runs up to 40vF. So far not a single dud out of 52 drivers, although they have yet to be tested for reliability.
 
Bueno Time

Bueno Time

Well-Known Member
SupraSPL said:
Java, I love that driver but I am having a problem with the seller. They sent me a shipment of drivers that are slightly longer than the original I tested. These new drivers were defective. Vf range only goes up to 25, they only put out 700mA @ 37vF and the operate at 83% efficient. To be honest I am angry at the seller. They made me return the drivers to China to prove my complaint despite photos and I have been working with them for over a month to try and get (half) my money back. Hopefully other DIYers dont get anything from that defective batch.

This driver on the other hand, has been performing great, puts out over 1400mA and runs up to 40vF. So far not a single dud out of 52 drivers, although they have yet to be tested for reliability.
Click to expand...
Damn Im glad you posted this! I was looking at the vF max and crapping my pants just now thinking it might not work. I bought 3 of those drivers you just linked and they have a vF listed on the case of 37V max I thought I got the wrong drivers for a second.

 
Last edited:
SupraSPL

SupraSPL

Well-Known Member
Thanks SDS awesome graphs I love it!

SG, those 50W Fasttech drivers are a perfect match for the Vero 18, it should put out about 1.25A. A 3000K Vero 18 should run at a minimum of 32.5% efficient, dissipate 38W and cost $1.64/PAR W. That is a very cost effective setup.
 
SomeGuy

SomeGuy

Well-Known Member
SupraSPL said:
Thanks SDS awesome graphs I love it!

SG, those 50W Fasttech drivers are a perfect match for the Vero 18, it should put out about 1.25A. A 3000K Vero 18 should run at a minimum of 32.5% efficient, dissipate 38W and cost $1.64/PAR W. That is a very cost effective setup.
Click to expand...

Cool. so that means I would be running about a 450w fixture with 12 of them going. What about casing those fast tech drivers? or using the ones you just linked to on ebay. I like having an enclosure for them.
 
You must log in or register to reply here.
Top