I've made a relay circuit for the Arduino to switch on and off a heater wirelessly, but I am struggling to find ways to power the Arduino? It seems pointless having a battery to power something to toggle the mains. I wondered about powering the arduino using a 5v dc converter and powering it in the same circuit, but obviously when the circuit is broken the arduino loses power! I hope im not missing something obvious.
Yes, connect a wallwart to the pre-switched mains and feed the arduino power from that.
Example to feed into the barrel jack: http://www.dipmicro.com/store/DCA-07510
I've got a transformer and a voltage regulator, i just wasn't sure if there were any problems with running the transformer in parallel to the device! Thanks!