DiY LED Grow Lights with CREE CXA3070 COBs and CPU Coolers

chief herb

Active Member
arduino 5v to pin 3...
pin 3 is Vref for pin 5 analog. nice feature for analog dimming with a pot. --> build in powersupply.
https://www.rollitup.org/t/led-diy-making-of-a-dj-set-style-grow-led-light.619348/page-7#post-8629816


Arduino GND to pin 2
and an Arduino pwm pin to pin 4
Guod,
I hooked up an RCD-48 to an LED and cannot seem to get it to dim with the arduino. I have the power supply hooked up to pin 1 for vin and pin 2 to the ground, pin 4 to an arduino pwm pin, pin 6 and 7 to the LED, and connected the arduino ground to the ground on the power supply. When the power supply is plugged in the LED comes on at full blast and changing the value for the pwm pin does nothing. Can you possibly help me get this thing working?
 

chief herb

Active Member
where to start?

PWM Frequenz ? 200 -1000 Hz

Portconfiguration? you need 5V for "off" and 0V for "on"
PWM Dimming Controlled page 4
http://www.recom-international.com/pdf/Lightline/RCD-48.pdf


most arduinos work with 3.3V, we need 5V for the RCD48 PWM port

Software?
I am using an arduino mega with pin 9 for pwm. I'm not sure what the pwm frequency is, it is just what it is automatically set to. Do I need to change the frequency to 200hz? Also how do I set up the pwm to be on 5v instead of 3.3v?
Thanks for the help
 

chief herb

Active Member
Do I need to change the frequency to 200hz?
any frequency from 200 up to 1000Hz works...
default frequency for arduino mega is 490Hz on pin 9

Secrets of Arduino PWM


if you mean this one,
http://arduino.cc/en/pmwiki.php?n=Main/ArduinoBoardMega
then voltage is not a problem here, it runs on 5V.
Well if it is not the frequency or the voltage I am not sure what the problem is. I just tried it on an arduino uno rev3 and got the same results. When I connect the pwm pin I notice a very slight decrease in light output and the light seems to flicker extremely fast but changing the pwm value with analogWrite does nothing.
 

chief herb

Active Member
Here is my sketch, simply trying to turn the LED off with setting analogWrite to 0.

int ledPin = 9; // LED connected to digital pin 9
void setup()
{
pinMode(ledPin, OUTPUT); // sets the pin as output
}
void loop()
{
analogWrite(ledPin, 0); // analogRead values go from 0 to 1023, analogWrite values from 0 to 255
}
 

chief herb

Active Member
reverse logik here...see post #62

simple on/off
void loop()
{
digitalWrite(ledPin, HIGH); // sets the LED off
delay(500); // waits for a half second
digitalWrite(ledPin, LOW); // sets the LED on
delay(500); // waits for a half second
}

analogWrite...
http://garretlab.web.fc2.com/en/arduino/inside/arduino/wiring_analog.c/analogWrite.html
Sorry if I was unclear, I was simply saying I couldn't get the light to turn off for a starting point. I want to use analogWrite to be able to dim the lights using the analogWrite values of 0-255 for pwm dimming. I have done this with 3W LEDs and different dimmable drivers. digitalWrite HIGH and LOW do work to turn it on and off but I would like to be able to dim them. I got analogWrite to work by removing the void setup where I set the pin as an output but it only works for one led at a time, when I try to dim one and turn the other on I get funky results. The same goes for the ledfademaster library, with one led it works but when I try to hook both up it screws up. I will post my question in the arduino forum to see if anyone there can help and I will post back here if I get a solution, or start a new thread with my build.
 

guod

Well-Known Member
again...
a higher Value on the analogWrite command . gives a lower Output current.

analogWrite(ledPin, 255); // sets the LED off
digitalWrite(ledPin, HIGH); // sets the LED off

analogWrite(ledPin, 0); // sets the LED on
digitalWrite(ledPin, LOW); // sets the LED on

try this
light ramps up with a longer delay in the Off-state

void loop()
{
analogWrite(ledPin, 160); // sets the LED 33%
delay(500); // waits for a half second
analogWrite(ledPin, 80); // sets the LED 66%
delay(500); // waits for a half second
analogWrite(ledPin, 0); // sets the LED 100%
delay(500); // waits for a half second

analogWrite(ledPin, 255); // sets the LED off
delay(1000); // waits for a second
}
 

chief herb

Active Member
again...
a higher Value on the analogWrite command . gives a lower Output current.

analogWrite(ledPin, 255); // sets the LED off
digitalWrite(ledPin, HIGH); // sets the LED off

analogWrite(ledPin, 0); // sets the LED on
digitalWrite(ledPin, LOW); // sets the LED on

try this
light ramps up with a longer delay in the Off-state

void loop()
{
analogWrite(ledPin, 160); // sets the LED 33%
delay(500); // waits for a half second
analogWrite(ledPin, 80); // sets the LED 66%
delay(500); // waits for a half second
analogWrite(ledPin, 0); // sets the LED 100%
delay(500); // waits for a half second

analogWrite(ledPin, 255); // sets the LED off
delay(1000); // waits for a second
}
I was out of town last week and didn't have time to mess with this project. That code still gives me strange results. I went ahead and pulled a Meanwell LDD driver out of my terrarium light and it works for me with no problems. The difference in light output is small when stepping down to 1A that the LDD driver outputs and they are only $7.25 from rapidled.com so I will stick with those. I probably had something wired wrong on the RCD. Now the only thing I have left to figure out is where I can buy a 2700k cxa3070, everywhere has a minimum order on that one. Thanks for the help, hopefully I will have this light running soon.
 

epicfail

Well-Known Member
I haven't come across any 2700k 3070 yet (I haven't looked in a while), they are available in a 3050 and 3590 for sure though. The 3000k does a great job and I wouldn't hold out for the 2700k when the 3000k has proven results.
 

coolj

Well-Known Member
where can i buy this stuff


Easily build your own high-power LED Grow Light using COBs!

(Built with assistance of RIU contributors! - Original thread )


[HR][/HR]
Battlestar Ganjatica - A 480 Watt Multi-Mode LED Grow Light


6x CREE CXA3070 @ 3000K - $36ea ($216)

2x CREE CXA3070 @ 5000K - $38ea ($76)

8X Meanwell LPC-60-1400 Drivers - $20ea ($160)

8 Arctic Cool CPU Coolers - $9ea ($72)

Rhino 12v External HDD Power supply - $9 (for powering fans)
1 Tube Thermal Adhesive - $8

3'x1' White Shelving board - $10

4x Bottom Sliders for Drawers - $7ea ($28)

(link is not exact model. I only paid $7 each in-store)

3x 2-way Switches - $4ea ($12)

4 heavy-duty stainless eye bolts - $1ea ($4)
(in-store)

10 Pack In-sure easy wire connectors - $2

6-Pack Blue Mid-line connectors - $2

TOTAL PANEL BOM: $599

MISC Other Materials:




Ignore the fan-speed controller. Didn't end up using it.


[HR][/HR]

Wiring is pretty basic. Just scale up the below diagram (provided by RIU member Goud)




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And here you go!






3 Modes: Veg, Teen, Bloom







Preliminary Results look good!

First day over plants:


Week or so later:



where can i buy this stuff? also can or do you have a vid on how to put this together?

?
 

mauricem00

Well-Known Member
found something interesting on ebay http://www.ebay.com/itm/361088292529?_trksid=p2060778.m1438.l2649&var=630431587294&ssPageName=STRK:MEBIDX:IT warm whites may be great for flowering but adding 1 or two of these to the array would give a fuller spectrum and may help with vegging. one large led grow light maker uses 430,460, and cool white leds with 630 and 660nm to get full spectrum coverage and many growers have had good luck with these lights. a few quick calculation indicated that one of these with a single 50 watt warm white would produce a very balanced spectrum (R/B 1:1) so you would not need very many
 
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