RedCarpetMatches
Well-Known Member
I seen that! For a measly $550. There're compatible ballasts on ebay for 120$. My 860w is amazing, but doesn't help the power bill. I like the idea of CMH with supplemental 660nm LED.
DiY LEDs - How to Power Them
- Thread starter SupraSPL
- Start date
PSUAGRO.
Well-Known Member
Comparable ballasts at that price? Really........got a link? Pretty hard to find an appropriate base a well I think.......would love to see you piece this together cheap......because I love that bulb
RedCarpetMatches
Well-Known Member
I'd do anything to help ya out buddy!!! Sockets...no prob. Ballast was hard to find last I checked. I'm piss drunk on St. Gingers day. I'll PM ya so hard when I get the links.Comparable ballasts at that price? Really........got a link? Pretty hard to find an appropriate base a well I think.......would love to see you piece this together cheap......because I love that bulb
Sorry for the thread jackin...NOT!!! kiss-assIs this a good deal
30 Watt Cree XPE Blue Red Multichip LED + 30W LED Driver For Plants Grow Light $35.99
http://www.ebay.co.uk/itm/30-Watt-Cree-XPE-Blue-Red-Multichip-LED-30W-LED-Driver-For-Plants-Grow-Light-/200975207584?pt=US_Hydroponics&hash=item2ecb0e4ca0
30 Watt Cree XPE Blue Red Multichip LED + 30W LED Driver For Plants Grow Light $35.99
http://www.ebay.co.uk/itm/30-Watt-Cree-XPE-Blue-Red-Multichip-LED-30W-LED-Driver-For-Plants-Grow-Light-/200975207584?pt=US_Hydroponics&hash=item2ecb0e4ca0
Specification for LED:
Power: 30W
Chip Model: XPE-R2-N4, XPE-B3
Emitted Color: Blue+Red (5pcs Blue Leds + 5pcs Red Leds)Wavelength: Blue: 460-470nm, Red: 620nm-630nm
DC Forward Voltage (VF): DC24-28V
DC Forward Current (IF): 1000mA
LED Viewing Angle: 110 degree
Size: (L)55 x (W)40 x (H)2mmSpecification for Driver:Input: AC100V-240V 50/60HZ 0.36A
Output: DC24V-38V 1000mA+-5%Efficiency: 85%
PF: 0.95TA: 50°TC: 60°
Protection rank: IP65
Size: 118(L) x 38(W) x 29mm(H)
Weight: 190g
Power: 30W
Chip Model: XPE-R2-N4, XPE-B3
Emitted Color: Blue+Red (5pcs Blue Leds + 5pcs Red Leds)Wavelength: Blue: 460-470nm, Red: 620nm-630nm
DC Forward Voltage (VF): DC24-28V
DC Forward Current (IF): 1000mA
LED Viewing Angle: 110 degree
Size: (L)55 x (W)40 x (H)2mmSpecification for Driver:Input: AC100V-240V 50/60HZ 0.36A
Output: DC24V-38V 1000mA+-5%Efficiency: 85%
PF: 0.95TA: 50°TC: 60°
Protection rank: IP65
Size: 118(L) x 38(W) x 29mm(H)
Weight: 190g
SupraSPL
Well-Known Member
It is a very blue spectrum. Each blue will dissipate more power than the reds so it is probably 65-70% blue. IMO you don't need more than 30% blue for vegging.
They are suggesting that you can put "10" "5W" leds in series. That is confusing and basically useless information that many chinese drivers include. The important driver info is: drive current 1A and vf range is 24-38V.
Since this is sort of a DIY project that you will have to solder, for the price I would encourage you to use a COB instead. You will get higher efficiency, more wattage and a more correct spectrum (much less blue).
They are suggesting that you can put "10" "5W" leds in series. That is confusing and basically useless information that many chinese drivers include. The important driver info is: drive current 1A and vf range is 24-38V.
Since this is sort of a DIY project that you will have to solder, for the price I would encourage you to use a COB instead. You will get higher efficiency, more wattage and a more correct spectrum (much less blue).
WDIK
Active Member
Is that a genuine Cree? I ask because I don't know. I would be careful.
Mellodrama
Well-Known Member
How can you tell a counterfeit Cree from genuine? I mean, a counterfeit isn't much good unless it looks just like the real thing...
WDIK
Active Member
I honestly didn't like the look of the "CREE" font. I have no idea if they or real or not, but I do know many companies are particular about their branding. :shrug:
Authentic Cree:
Observe & Report
Well-Known Member
XPE's are bare emitters, not COBs. The COB in the auction is made by someone other than Cree, that's why it doesn't have the same branding as a CXA. Whether it has authentic XPEs on it, I couldn't tell you.
Observe & Report
Well-Known Member
They aren't chips on a board?
Observe & Report
Well-Known Member
If they aren't on a PCB, why are there only two contacts for nine chips?
Certainly there is a difference between bare chips on a board that amounts to a single package and individually packaged chips on a board, but they both consist of chips on a board. Both are multichip arrays, too. All COBs are multichip arrays but you are asserting that these multichip arrays aren't COBs, why? Also, what is the significance to us?
Certainly there is a difference between bare chips on a board that amounts to a single package and individually packaged chips on a board, but they both consist of chips on a board. Both are multichip arrays, too. All COBs are multichip arrays but you are asserting that these multichip arrays aren't COBs, why? Also, what is the significance to us?
FranJan
Well-Known Member
Multis aren't as efficient at creating light as a COB. Would that be a good enough reason why it's important? COBs are never exposed, always encapsulated. Always wired VERY tight. Therere are a few more difference like production, wiring., die size. I'm sorry I'm at work and can't link to the company's website that owns the patent on COBs. And why even come up with the name cob when smd was already there.?After all they're all mounted on a surface, right? COBs are mounted directly onto PCB boards, not metal. It's why the call them COBs. You didn't even bother to try to find out what I said is true, when I said look it up did you? Naaaa it's much easier to think you know what you're talking about. Later.
Observe & Report
Well-Known Member
I see you're talking about what the actual piece of silicon and not what is colloquially called a "chip."
Cree XML-2 80-CRI 2600-4300K bin T2 @ 700ma (test current) 85C = 100.25 lm/W
Cree CXA3070 80-CRI 3500/3000K bin Y4 @ 1925ma (test current) 85C = 93.25 lm/W
Cree XML-2 80-CRI 2600-4300K bin T2 @ 700ma (test current) 85C = 100.25 lm/W
SupraSPL
Well-Known Member
The Cree XM-L2 and CXA COBs are both very impressive impressive in terms of efficiency but the 3000K CXA3070 is much cheaper and much more efficient.
The best 3000K XM-L2 is the T5 bin available at Cutter for $6.35. The T4 bin is available from Aliexpress in 7A3 and 7A4 tint for about $5 each. At test current the T5 bin is 130lm/W or 39.6% efficient but it cost $3.12/W.
The best 3000K COB currently available is the CXA3070 Z2 bin available from digikey for $40. At test current the Z2 bin is 99.3lm/W or 30.27% efficient but it cost $0.53/W.
--------------------
So if we go by the arbitrary test current, the XM-L2 is running soft and the CXA is hard, not a realistic comparison of how they would be used in a growing lamp. Here is a growing lamp based comparison @ TJ 50C:
XM-L2 T5 at 1.5A creates 115.5lm/W which is 35.23% efficient and cost $1.36/W
CXA3070 Z2 at 1.05A creates 128lm/W which is 39.1% efficient and cost $1.05/W
In this comparison the CXA3070 creates 11% more photons and is 25% cheaper. It is also much easier to build a large lamp with COBs. Another problem with the XM-L2, every star needs to be sanded to 1000 grit because they are not even close to flat. Even a 60 grit sandpaper will improve the metal to metal contact that is terrible. CXA ceramics are truly flat and ready to install right from the factory. Cree recommends you flatten the aluminum heatsink surface you are mounting the CXA on to 1000 grit or a roughness of 10 micrometers.
The best 3000K XM-L2 is the T5 bin available at Cutter for $6.35. The T4 bin is available from Aliexpress in 7A3 and 7A4 tint for about $5 each. At test current the T5 bin is 130lm/W or 39.6% efficient but it cost $3.12/W.
The best 3000K COB currently available is the CXA3070 Z2 bin available from digikey for $40. At test current the Z2 bin is 99.3lm/W or 30.27% efficient but it cost $0.53/W.
--------------------
So if we go by the arbitrary test current, the XM-L2 is running soft and the CXA is hard, not a realistic comparison of how they would be used in a growing lamp. Here is a growing lamp based comparison @ TJ 50C:
XM-L2 T5 at 1.5A creates 115.5lm/W which is 35.23% efficient and cost $1.36/W
CXA3070 Z2 at 1.05A creates 128lm/W which is 39.1% efficient and cost $1.05/W
In this comparison the CXA3070 creates 11% more photons and is 25% cheaper. It is also much easier to build a large lamp with COBs. Another problem with the XM-L2, every star needs to be sanded to 1000 grit because they are not even close to flat. Even a 60 grit sandpaper will improve the metal to metal contact that is terrible. CXA ceramics are truly flat and ready to install right from the factory. Cree recommends you flatten the aluminum heatsink surface you are mounting the CXA on to 1000 grit or a roughness of 10 micrometers.
RedCarpetMatches
Well-Known Member
660nm is where it's at. Look at the CX2540s 93cri 3000k..couldn't imagine the 2700s with 93 CRI. http://www.cree.com/LED-Components-and-Modules/Products/XLamp/Arrays-NonDirectional/XLamp-CXA2540. Wish I could tell you efficiencies.