Re: Opinions and advices for my new cheap idea. LUXEON COB GEN 4 (2.5 X 2.5)
Posted: Sat Mar 24, 2018 12:17 pm
Hey,axef wrote: ↑Tue Mar 20, 2018 10:40 amHello folks
I extrapoleted datasheet spectral distribution chart and elaborated to convert it in numerical data.
With numerical data, it is possible to integrate power over wavelenght in order to calculate PPF.
Below PPF for some COBs @ 1000mA, and assuming a LED efficiency of 30% (the capacity to transform electrical power in light):
L2C2_70_5700K
ppf: 48.03453837990068 umol/s
L2C2_80_2700K
ppf: 49.01280628712339 umol/s
CXB3070_80_3000K
ppf: 47.878880284205316 umol/s
CXB3070_90_3000K
ppf: 45.778220550503654 umol/s
Please consider that I've NOT measured the real ppf, and values reported are only results from theoretical calculations. Could anyone validate data for CXB3070? Is calculation close to the real output?
I'm not sure that 1208 COBs can provide enough power and the right light spectrum for growing plants.
Regards
Alex
By integrating spectrums, you can calculate the real efficiency of your led depending on the luminous flux (lm/w)
Using a CIE luminosity curve. First you got to normalise your led spectrum's curve to 1w, so if u got 1 point every nanometer you just divide the whole data to get the total amount =1
Then you calculate : 683*CIE curve*Led spectrum and it gives you the amount of lumens the spectrum produce for 1 radiant watt.
For exemple the CXB 3070 3000k 80CRI produce 330lm for 1 radiant watt.
so if your led, according to the datasheets, produce 165lm/w that means for each electrical watt the led produce 0.5 (165/330) luminous radiant watt.
basically an efficiency of 50%.
Concerning the photon flux, a 3000k led usually produce approximately 4.8umol/j. So for each radiant watt you are supposed to get 4.8umol/sec.