Quick question about CXA3070 and led drivers.

Hello all. First off merry Christmas to all.im interested in building a grow light for my plants, I'm just a tad confused about a few things. As I don't want to go over 250 watts I understand even if a led is rated let's say 32 watts you want to run them at a lower wattage is that correct? Now is the only way to "soft" drive them is to get a dimmable led driver? Is that also part of when people say efficiency and such? I'm sorry for the newb questions.

Efficiency is roughly the amount of power being turned turned into actual light [photons] and how much is lost to heat and circuitry. If you are running at 40%....40% of electric, is being turned into light.


Dimming a diode, yes, technically, can lower the current [Amperage] to run them "softer" and hence more efficiently.

You don't need a dimming driver, though, just a driver with less current. So for example, quite a few run the 3070 @ 1.4 amps.
Cree's rated voltage at that amperage is roughly 37.30 volts and depending on bin,[AB 3000k] is 42%. So 37.30 * 1.4 = 52 watts. SupraSpl, one of the cree cob guru's, run's his Cree's @ 700mA, so half of the above example. His efficiency is roughly 49% with a lower current.

Here is a spreadsheet put together by Supra that calculates Voltage Forward [VF] and Current. Also calculates efficiency, wattage, etc.

Just realized that the Cree #' are correct, but diregard the Vero #'s, those have been updated and forgot to do that. But the Cree's are good

Ty so much for the spreadsheet and explanation. So since he runs at 700 his actual wattage would be 26 watts correct, also I'm assuming that would reduce the amount of lumens as we'll. also do the Crees need to be spaced a certain amount of inches apart as I see the 3w led needs to be placed really close.

Sorry one more question is the 3000k more or less full spectrum I'm actually doing bonsai peppers ,so I think I need more veg per say then flower.

Andrew1981 said:

Ty so much for the spreadsheet and explanation. So since he runs at 700 his actual wattage would be 26 watts correct, also I'm assuming that would reduce the amount of lumens as we'll. also do the Crees need to be spaced a certain amount of inches apart as I see the 3w led needs to be placed really close.

Click to expand...

It does reduce the overall amount of lumens, but if you look at the chart, the more efficient you run your diodes [i.e. less current], the more Lumens per/ watt increases.....the softer you run.