Hi!
I want to automate some lights and outlets in my house with Arduino, but after thinking looking some solutions I have some doubts:
If one on-off wall switch is replaced by a new on-on switch (to later be able to schedule power cycles) what is the safe length for the 5V rails to work correctly? or should I use another method?
Is the atmega suitable for the expected reliability, or there is some compatible solution more suitable? Any personal experiences?
Thanks
- If one on-off wall switch is replaced by a new on-on switch (to later be able to schedule power cycles) what is the safe length for the 5V rails to work correctly? or should I use another method?
What are you driving?
- Is the atmega suitable for the expected reliability, or there is some compatible solution more suitable? Any personal experiences?
The Atmel chips (and there are many not just one) are just as reliable as any other chip.
Mark
Sparkfun sells some plugs you can control with 5v outputs. You can start from their and find the hardware that matches your needs. Atmega is only as reliable as your programming skills. I have projects in dozen locations out in the cold winter way below freezing, working around the clock with various hardware. They dont break down because my code is good. 8)
What are you driving?
It is just for the signal (length = L):
It is invisible because the things keeps looking and working as before. The arduino switches to !state (open/closed) in reverse (for example if the manual wall switch is opened, and the light is ON, but the schedule says the light will go OFF, then the switch will turn of the light when is closed).
liudr:
They dont break down because my code is good. 8)
Nice! So mine will not break either 
You have to rewire your house. Everything, switch wires and light power wires, goes to a central panel where all the relays are. Then you install arduino there to do the relays. Test your wire length with arduino. Use strong pull up or down.