automation box project

Projects General Guidance
1

If I pickup a 12v power supply how many amps is good for this board:

Also, I could simply power it through the USB port, the cubietruck I am connecting it to has a 3A 5v power supply. Would this be good enough? Or would a separate power supply for the arduino be better?

It's going to be a tight fit, I am using a 240v breaker, which means if I want any space at all I have to stack the arduino on top of the cubietruck.

Also I am wondering about the cable issues... I need a nice and bendy hdmi cable and a few usb cables -- anybody know of good places to buy flat ribbon like ones? Seems the cables are going to be a bit of a pain for this box...

Technically I don't need all the terminals there, this particular box probably won't be needing all that.

Any thoughts on this?

2

The Mega can be powered from a USB port which means it uses less than 500milliamps at 5v.

Since you are talking about power supplies with much higher amperages I wonder if you are planning to use external components (relays, servos etc) which draw extra power. If so they should not draw their power from the Arduino board.

I don't feel qualified to comment on any other issues, especially high voltage components which may present dangers to persons.

...R