I have a small 200A capable welder. Max rated inrush is ~40A for a short period. (not enough to trip a 20A 120V breaker, and it's a bit less when running on 240V.) bigger welders are much, much more thirsty. This is why you cannot go poking about willy-nilly in the guts of a welder, since the caps are beefy and can easily kill you. But it makes a really good test of the system.