OK everybody slow down, lets look at some fundamentals:
a 72V cob run at a given current looks identical to a driver as a 36V driven at double that voltage. the arrays real limitation is WATTAGE.
from CREE PCT for CD bin 3590, 72V on right, 36V on left:
View attachment 3613936
look at 3.6A on the left vs 1.8A on the right. see how the wattage and efficiency (lumens per watt) are basically identical, and the voltage is exactly doubled?
thus is the nature of a 36V vs 72V cob- how its wired internally, its really the same array jsut wired differently.
advantages to the higher voltage cob are primarily they can be run hotter on a given driver. meanwell doesnt make drivers (in the popular constant current versions) over 1.4 or 2.1A depending on model. were leaving a lot on the table by only runing them so soft. so in the example above, a 1400ma driver cannot run a 36V cob over 48.77W per cob, but it can run a 72V cob up to 104.293W
is it magically running the cob at more than twice efficiency because the wattage is more than doubled? NO!
its just running it at a higher wattage which is less efficient
if you used a different driver you could run the 36V cob at 2.8A and look at the table... bingo! the same 104.293W
is it "more efficient" at double the current because it magically "creates" more than double the watts? NO! it is less efficient. it CONSUMES *more* than twice the watts and puts out *less* tan twice the light
chomp on hat and ill come back and answer sir ttystikks specific question