I was trying to give OP a quick and dirty example to get them in the ballpark. We haven't even considered voltage drop in the wire or the start up current draw. If I was installing this circuit based on the 3600 watt example I would be designing, based on experience, for a minimum 50 amp breaker.

Now I admit, I'm not an electrical engineer or even an electrician. I'm just a lowly PMEL tech who calibrates and repairs all of the test equipment.