Basically i am building a LED array of 900 LED's (600 White, 300 Blue).
I am setting it up with 200 White LED's (2x100 Configuration) in 3 Banks and 100 Blue LED's in between each white bank.
I hope you can follow because this is about as best as i can explain it.
Originally i was just going to going to use LED dimmers to fade between the white and blue, however using an Arduino for automation seems much cooler. ;D
What i am trying to do is control the lighting in a gradual fade between the blue and white LEDS using a Duemilanove.
According to the specs of the Duemilanove the maximum output from the unit itself is 50ma. Since this array is going to be well over this I am trying to figure out how to get the Duemilanove to interface with something to control the light.
What i hope to achieve is using a RTC to set the times for the fades over a 24 hour period.
All i have at the moment is a Duemilanove and the LEDs (and resistors).
What else will i require to achieve this?
Robert, you have lots of learning to do.. I'd suggest heading over to the reefcentral DIY forum and reading the LED posts till you are blue in the face. #1-using 900 standard LED's is NOT the way to go..
Most people that go for aquarium lighting with leds use high power 3W led's from Cree or others. I'm in the process right now of a similar project using 24 x 3W (12 white and 12 blue) for a 30 gallon saltwater reed tank. I am using the Arduino to control the dimmer circuit for 2 meanwell constant current supplies ELN-60-48D.
I am smoothing out the PWM signal on 2 digital outputs and feeding that to an op amp (2x scaling) to produce a 0-10V signal.
I'd start looking into that method.
Mcgyvr - I too am building a 36 LED array using 4 meanwell ELN-60-48D's and have been researching the best way to utilize the Arduino for the dimming. I would be interested to hear how you designed your circuit, and how you plan to setup the timer.
mcgyvr, I'd be interested in the op amp you mentioned. Do you have instructions on how to set it up? I'm also setting up an LED system with the Mean Well ELN-60-48D, but I need a 10V PWM signal.
