ECN Forum Forums General Topics of the Trade General Discussion Area Most common US outlet for 3500 Watts?

Sounds like you'd be best off with 240 V 20 amp (in theory 15 amp would be enough but I think that'd be a violation of the rule that circuits shall only be loaded up to 80% under normal conditions). 30 amp 240 V is common for clothes dryers so if that's OK for short-circuit protection I think I'd go for that.