Hi 
I just wonder if anyone can help me?
I want to make a wireless controlled light dimmer.
I will use arduino to control my lights from my computer.
What I need is to make a trafo 0-230v AC to the lights.
Transformer must be electronic, and controlled by arduinos 0-5v DC.
I'm a bit unsure of how I could to control 0-5VDC to 0-230VAC.
Annyone?
Best,
Andy
Hi Richard.
In fact I'm a electrical engineer. But in last 6 years I've only been working with PLC systems. And I'm allowed to work with power up to 1090 v AC. I live in Norway by the way.
But now I want to see a little more basic in the electronics section. Learning about the structure of the parts so that I can create components for myself.
But low power electronics for me, is much harder to understand. Since this wasn't my primary education. I did some at school, so I do understand the basic of low power electronics.
Back to question...
I will use this to fade light up or down when you press a switch. Arrow up, light get brighter. Arrow down, the light gets weaker.
Or use arduino to program a wakeup function or use my computer to control the light.
You mention the "X-10". It's probably something similar of this I want. But as I mentioned earlier, I wanna learn how things work as well...
Best,
Andy 
Fading 230V AC lights requires special hardware. This topic has been discussed many times. Follow Richard's hint and search for "Arduino-controlled lamp dimmer".