Building The Ultimate 200w Cree Grow Light - 16 x Cree 1512 3000k 93cri $200

[BorisJohnson]

Is this the ultimate light for a 1x1m space?

Headroom not an issue although I assume a light with small cobs wants to be closer to the canopy for light penetration?

So far it will give me just under 20,000 lux, 200w max power in 3000k 93cri for $200

I have also found a version using 3 step latest bins not 4 step which will cost just under $40 the same as 1x3590. So in effect my 16 x 1512's beat the 3590 on price and power.

The only trouble is, I cannot for the life of me work out how to get a PAR or Micromole reading for it.

I know the cobs will be running at 90% rlux which equals 90% of my max lux output but how do I convey that info Micro-moles?

I can't really find any information on ppl using the 1512's, are they too small? I hear the more lights is better so I'm getting a very good even copy of light. Im just wondering if it will be enough.

I would use 3 x 3590's driven soft for similar power but that would cost more, give worse coverage, although more lux than you could shake a stick at! 30,000 compared to around 20,000 with the 1512's.


Are the 1512's a great idea that will just underperform? They only give off 1150 lux per cob so x that by 16
These are the 18v 1512's so can be used with 1x ELG-200H-C700B (nice)



Thanks in advance for your help.

 

[Old Salt]

Is this the ultimate light for a 1x1m space?

CREE 1812s are rated at 12.6W, and generate 86 lm/w
A square meter is close to 10.75 sq ft.
Light spacing is about 25cm or 10"
Sixteen 1812s requires 201.6 watts, which is 18.75 w/sq ft.
The recommendation for the veg stage is roughly 30 w/sq ft
The recommendation for the flowering stage is 35 - 50 w/sq ft
I think you'll have far too little light.

CREE has the reputation, but take a look at Citizen and Bridgelux as well. They are far more cost effective. the CLU048-1212C4-303H5K2s can be had for about $10 USD each.

Values other than lumens will need to be measured. You may be able to find someone that has done this on the forums.

I found this thread very useful in planning my lighting.

 

[415friendly]

If you google "convert lux to ppdf" you will find a link: PPFD to Lux Conversion

The approximate conversion to change lux to ppfd is to divide by 65 for a 4500k temperature light. Do some more research, and it seems you need to divide by somewhere around 69 to get the conversion for white COB LED's.

 

[Old Salt]

I'm not convinced the the beloved PAR is a reasonable measure of how a plant will perform under a light. Yes, I've heard the saying lumens is for people, PAR is for plants. Think of it though, you can have a high PAR lamp putting out light that is mostly useless to plant life. Green anyone? PAR is everything between 400 and 700 nm after all. Why then do manufacturers add light outside of this range such as far reds, infrared, and UV to their products? According to PAR, they should have no effect on a plant's growth.

Color temperature, CRI, and Lumen values, to me give a better indication of how well a plant will grow under a specific light. Even so, the LEDs and COBs made by different manufacturers, with the same color temperature and CRI have differing spectral distributions. Check out the following image where I superimposed Philips and Citizen offerings of 3000K 90+ CRI:

If you really want to dive into this mess, start with Photosynthetic Photon Flux Density (PPFD) - Concepts. I chose this site as it has conversion factors for the Philips LED.

Actual grows, especially side by side, such as those in a previously mentioned thread give a much better indication of how plants perform under a light.