Tag Archives: lights

COB LED Array

The Vero SE 29 Generation 7 COB LED array currently in production generates 100 W of true LED power that produces a photosynthetic photon flux density of 4600 umol/m^2/s from a single chip in our system, and is rated by the manufacturer to generate 201 W LED by changing the drive current from 2.1 A to 3.6 A. It connects to our system with inexpensive 2-conductor 20 AWG wires that push into place without any soldering.

Cree 3070N CoB LED array in earlier prototype increased power output

The forward voltage @ 1900 mA Tc=85 deg C is 36.2V. 36.2V*1.9A=68.8W. The forward voltage @ 1900 mA Tc=25 deg C is 42V. 42V*2.8A=117.6W. The percent change is 71% allowing the system to operate with 71% fewer LED lights.

https://www.calculatorsoup.com/calculators/algebra/percent-change-calculator.php?v_1=68.8&v_2=117.6&action=solve

Bridgelux CoB LED array currently in production increased power output

At 3.6 A, the forward voltage is 55.8 V resulting in 201.0 W LED output from a single chip.

The percent change is 192% allowing the system to operate with 192% fewer LED lights.

https://www.calculatorsoup.com/calculators/algebra/percent-change-calculator.php?v_1=68.8&v_2=201&action=solve

 

https://www.bridgelux.com/products/vero-se-series

part number on chip – 35E10K0B7

3500K

80 CRI

full part number – BXRC-35E10K0-B-7x-SE

Performance at Commonly Used Drive Currents:

900 mA 49.6 V 44.7 W
1200 mA 50.5 V 60.6 W
1800 mA 52.0 V 93.6 W
2700 mA 54.1 V 146.1 W
3600 mA 55.8 V 201.0 W

10 year warranty

Light Coverage

According to the manufacturer, the light source we had used in one of our prototypes has a beam spread of 115 degrees.

http://www.cree.com/led-components/media/documents/ds-CXA3070.pdf

Although we ran the LED array at 1.4 A constant current, we are able to safely double the current to 2.8 A by keeping the case temperature under 25 degrees Celsius with our heat sink that has a large plate transfer area coupled with water cooling.

The doubling of the current doubles the amount of light from the same device, and cuts the number of lights a farmer needs in half.

With the 115 degree light spread, we are able to space our microgreens pans vertically every 7.5″ with nutrient film hydroponics, 8.5″ with coconut weave mat, and 9.5″ with Speedling floating trays.