To resume my project I made a controller that activate a motor.
At first I was driving my relay directly from Arduino board. but this was a bad idea has relay use 73ma, way over the rating of the Arduino board.
Now that I busted my card I building another one but added an Optocoupler. Strangely even on a basic test I can't seem to activate the optocoupler.
I use an Arduino Duemilanove, a 470 ohms resistor, an optocoupler 4n35. The resistance should give around 8.5ma to the led. My Relay are goodsky rs-ss-105d
Here the simplest test I could have thanked and it still doesn't work. Even using multi-meter to test continuity doesn't seem to work between collector and emitter. I hope someone could explain me why it doesn't work.