need a good COB

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churchhaze

Well-Known Member
I see another problem actually... The voltage drop across the 9V cxa1304 is actually more like 10V at 650mA.

doh. you'd have to run 4 in series in that case! They probably call it a 9V diode because that's the forward voltage where the diode array is considered "on".
 
Thorhax

Thorhax

Well-Known Member
churchhaze said:
I'd be concerned about is that they'd be running at about 120% of the test current at 650mA. I'm not sure how efficient that would be, but it might still be pretty good. Maybe Supra would have an idea of their efficiency at 650mA.
Click to expand...
The max current is 1A, they were only tested at 400mA... Does this mean anything?
 
Thorhax

Thorhax

Well-Known Member
churchhaze said:
I see another problem actually... The voltage drop across the 9V cxa1304 is actually more like 10V at 650mA.

doh. you'd have to run 4 in series in that case! They probably call it a 9V diode because that's the forward voltage where the diode array is considered "on".
Click to expand...
I'm thinking about just buying new drivers... These are a headache
 
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churchhaze

Well-Known Member
Depends if you want to buy 6 cxa3070 and drive them way below test current or 24 cxa1304 and drive them slightly above test current.

I think the cxa1304 would be cheaper to setup, and have more even distribution, but the cxa3070 at that current would be a lot more efficient, with a very high startup cost.

also, the bigger cobs might be easier to mount. Lots of pros and cons to each side.
 
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churchhaze

Well-Known Member
@SupraSPL makes spreadsheets to quickly calculate the efficiency and startup cost per Wpar.

He probably would have good input on which route to go on this.
 
Mechmike

Mechmike

Well-Known Member
I have 96 of the CXA1304 emitters surrounding my plants. It's best to run the 1304's at 300-350ma. At that amperage the efficiency is above 100 l/w. I figure somewhere between 110-115 l//w. Still nowhere near the efficiency of the CXA3070 @650ma but those 1304s really make for great side lighting. My advice is to run your emitters soft if yo can afford the upfront cost. You will love the efficiency going forward.
 
SupraSPL

SupraSPL

Well-Known Member
Unlike the Veros, the CXAs do not perform as well in the smaller sizes. I use the CXA1512 as headlights but only because they are the largest COBs that will fit. When it comes to maximizing output, efficiency and minimizing cost, the large COBs are the best performers. On the other hand it is true that smaller COBs give a better spread. So if you are intent on using small COBs, I would recommend the Vero10 or Vero13 similar to Mr Flux setup.

I think those are very nice drivers and would be a great match with the CXA3070. At 650mA, the CXA3070 3000K AB cost $4.33/PAR W and is 49.5% efficient. It should draw about 34.8Vf and will dissipate 22.6W per COB. You could add some blues and reds to the string with no worries. It will give you more bang for your buck and slightly improve the efficiency of the driver.

Although they mention a minimum Vf of 30, the drivers will likely perform just fine under that limit although with a slightly lower efficiency. It is the maximum Vf that is sometimes a hard cap.
 
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Thorhax

Thorhax

Well-Known Member
SupraSPL said:
Unlike the Veros, the CXAs do not perform as well in the smaller sizes. I use the CXA1512 as headlights but only because they are the largest COBs that will fit. When it comes to maximizing output, efficiency and minimizing cost, the large COBs are the best performers. On the other hand it is true that smaller COBs give a better spread. So if you are intent on using small COBs, I would recommend the Vero10 or Vero13 similar to Mr Flux setup.

I think those are very nice drivers and would be a great match with the CXA3070. At 650mA, the CXA3070 3000K AB cost $4.33/PAR W and is 49.5% efficient. It should draw about 34.8Vf and will dissipate 22.6W per COB. You could add some blues and reds to the string with no worries. It will give you more bang for your buck and slightly improve the efficiency of the driver.

Although they mention a minimum Vf of 30, the drivers will likely perform just fine under that limit although with a slightly lower efficiency. It is the maximum Vf that is sometimes a hard cap.
Click to expand...
pulled the trigger on the cxa1304. I'm going to put 4 in each series. and connect them easy with http://www.mouser.com/Search/ProductDetail.aspx?qs=EibfsPFbZap5v7NeZR223g==
thanks everyone for yet again helping me turn a cheap light into a great light
 
Thorhax

Thorhax

Well-Known Member
Ple
SupraSPL said:
Unlike the Veros, the CXAs do not perform as well in the smaller sizes. I use the CXA1512 as headlights but only because they are the largest COBs that will fit. When it comes to maximizing output, efficiency and minimizing cost, the large COBs are the best performers. On the other hand it is true that smaller COBs give a better spread. So if you are intent on using small COBs, I would recommend the Vero10 or Vero13 similar to Mr Flux setup.

I think those are very nice drivers and would be a great match with the CXA3070. At 650mA, the CXA3070 3000K AB cost $4.33/PAR W and is 49.5% efficient. It should draw about 34.8Vf and will dissipate 22.6W per COB. You could add some blues and reds to the string with no worries. It will give you more bang for your buck and slightly improve the efficiency of the driver.

Although they mention a minimum Vf of 30, the drivers will likely perform just fine under that limit although with a slightly lower efficiency. It is the maximum Vf that is sometimes a hard cap.
Click to expand...
so hooked up four of them and nothing happened when I turned it on. image.jpg
 
Thorhax

Thorhax

Well-Known Member
I checked them. Everything is good. So idk.. Do I have to have both outputs hooked up for a driver to give power out?
 
Thorhax

Thorhax

Well-Known Member
image.jpg
Connected the wires to the driver with hot glue. Redoing it with solder.

Didn't want to the first time cause I nervous about fucking it up... Lol
 
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