Back again - So an electrician here says the 100 Amp box doesn't sound right to him, that it's because you guys are thinking in American voltage. Can someone check my math? The heat sticks are 4500 watt 230V, and my power supply is 230V, the calculation for amps required is w/v * 1.2, right? == 23 Amps with safety margin. He said he wasn't sure because he said all houses here are on 60amp, even most big restaurants. 200 amp is almost never seen except for giant factories, and 100 amp is only really used for huge buildings. Does this sound right? I trust the guy, but I don't understand the theory and would like to.