I have a Lincoln 175 TIG setup in my garage that is powered via a 30 amp circuit. According to the owners manual it requires a 70 amp 220 connection to deliver the full 175 amp rating. My setup works fine up until about the 100-110 amp level - then it will blow a circuit breaker. Since I use the machine mainly for fine work (sheet metal) I really don't care about about utilizing the higher end of the amp spectrum - I typically do most of my welding at the 20-40 amp level.

At the 100 amp level I can weld steel up to about a 1/4 inch plate and aluminum up to about 1/8 inch - If you are going to be dealing with materials thicker than this you are most likely going to need a higher amp service rating.

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