big diy multichip led lighting with realtime weather

am.gee

New member
hi,
first i want to introduce myself a little bit. My name is Michael and i'm in the hobby for about 16 years now. My tank is a decent 520g mixed reef tank. I'm a sps lover, but dont ask me about colors of my corals :spin3: I rather have a growing brownie than i dying pinkish purple yellow one.
I have to thank all contributors here on RC, fantastic! I'm silently reading here for years and learned a lot, thank you!
For now I want to introduce my new baby. A big LED fixture build on my own, completely. A big problem with commercial fixtures is often, that you have no chance to see them in action. You dont know if a fixture has enough power for your tank. And then there are all the LED 'haters' out there... But i wanted to switch from a MH, T5, Led combo (800 watts) to pure LED, nevertheless. Because i like to start demanding projects and i had absolutly no idea about electronics this was a nice project. So here are the facts and finally a video:
660 watts total (for the moment, upgrades are on the way...)
3 x 100 watts multichip led 12 K
18 x 20 watts multichip led 8 450 nm leds, 10 x 12K cool whites
real time weather simulation updated every 2 minutes, weather data taken from a weather station on Cayman Islands, or any other station i want.
5 different degrees of cloudiness
exact sunrise/sunset time
moonphase and moon travels over the lamp over night
softstart after sudden power off
remote controlling and monitoring via web application from everywhere on the planet where i have access to the internet.
What i like with this build is the possibilities you have with leds. Once I turned the fixture on, I never ever wanted to go back to the old 1980's style metal halides :beer:

here the video, please feel free to ask me, what you want to know about the build.
It was sometimes not easy but i'm quite happy with it. It is running for more than 3 months now and it runs absolutly rocksolid stable. My corals didnt noticed a big difference to the old lighting system. Maybe its because it is rarely running on full power due to the bad weather on the Caymans :smokin: It's often Partly Cloudy there. Some of them changed their color, but not that much. I'm planning to upgrade the fixture with some 10watts multichips for more ambient light, like t5s. I can document that if you like.

Here we go:

http://www.youtube.com/watch?v=P7i0LkUfnf4

with best regards,
 
This is amazing. Thanks for sharing. Can you speak to the led layout of each multichip? One arduino mega had enough channels of control?
 
This is amazing. Thanks for sharing. Can you speak to the led layout of each multichip? One arduino mega had enough channels of control?

Thank you.
These multichips are all single colored (i think they are chinese ones). The whites are rated to be 12000 Kelvin and the blues are specified to be in the 450nm range. So they are nothing special, but seem to work. For the next upgrade i will use 20000 K chips (10 W each) without lenses for a wider spread of light (to simulate T5, although i know its not possible to replicate T5). The upgrade is for supplementation not for replacement.

No, the arduino has not enough channels for control (15 pwm channels). In the first versions i implemented some software pwm for the missing outputs. But later i decided to install a 16 channel 12 bit pwm board by Adafruit. So for the most channels i have 12 bit resolution for dimming. I will add another one for the planned upgrade of the fixture. Furthermore there is a prototype board installed with some little custom circuits for splitting the pwm signals for the three 12cm Fans on the 100w LEDs and to read their temperatures.
 
Last edited:
Here is an image of an early version of my fixture with just 5 x 3 multichips.
 

Attachments

  • Foto 2.jpg
    Foto 2.jpg
    63.6 KB · Views: 4
I love thuis build ! Could you share your arduino and raspberry pi code with us?

I can do that, although I dont really believe, that this helps.as you know, Code on Arduino always depends strongly on your Hardware, i.e. which Arduino you use, which shields are installed and how are things connected.
In this project I use an Arduino Mega with an I/O expansion board with XBee module installed, a 16 channel pwm board and a prototype board with a little circuits of my own. Many things are more or less hardcoded (for performance).
The Raspberry side is no magic (besides the fact, that it uses an XBee module too, of course). It is a Java Webapplication running on a Tomcat.

You can always ask me, if you are struggeling with your Arduino project and I can give snippets from my project. This should definitely help a lot more. If there is anything you are interested in, especially, ask me, although i'm nevertheless still no expert on Arduino. :beer:
 
Thanks I have an arduino that is currently controlling my leds and I am learning to code , I was already thinking of putting an raspberry pi on it to have internet control and those cool features of you. I thaught that it would be a good exemple to learn the code. 😉
 
Thanks I have an arduino that is currently controlling my leds and I am learning to code , I was already thinking of putting an raspberry pi on it to have internet control and those cool features of you. I thaught that it would be a good exemple to learn the code. 😉

Ah, I understand this. But it is really a not too simple project, which was even for me (i'm a coder for more then 25 years and a professional since 16 years...) quite demanding to develop. Let me know, what you want to know in detail.
 
Ok thanks, lets begin with that simplex noise algorithm , my leds are currently running on a scedule. How did you use this algorithm on your leds ?
 
Ok thanks, lets begin with that simplex noise algorithm , my leds are currently running on a scedule. How did you use this algorithm on your leds ?

imagine this fixture as a big screen with nearly hd resolution of 7 x 3 pixels :dance: i have some form of framebuffer of that size. with the algorithm i fill that buffer and when its time to draw it, i put that buffer into the displaybuffer. this is some kind of doublebuffering. currently i dont copy one buffer into the other dircectly, but do some fading or blending between them. the time of this fade process depends on the wind speed. also depending on windspeed is the time such an image is displayed until the next image will be 'rendered'. you can use the current displaybuffer values to feed in this algorithm, add a little to x and y depending on wind direction and there is your cloud animation.
 
here is a full tank shot with all leds on full power. i see there is potential for the upgrade
:celeb3:
 

Attachments

  • image.jpg
    image.jpg
    35.7 KB · Views: 4
Back
Top