Yes, and you should have a good one, as it can cost you an engine rebuild, as can bad extension cords. We use nothing but 10 to 8 gauge depending on distance to power. The farther away the more strain on the engine.
We have a couple electrical engineer types in the group so we can push it some times. The 8 gauge is for stuff over 200 feet. 10 gauge will get is most 100 feet but not with heavy use or big tools, and not for long durations, even that limited used causes strain from what I am told.
I have always required a electrical supply or rare case generator as a contractual condition. Every site that's wired to grid that I've worked at has 220v and 110v. Beside that, any successful power transformer will require adequate amperage so a visit to the breaker box is still required.
