@forty2 @ottaross To get a reduced mains voltage without the need for a big variac, you can use a 125V mains-powered transformer (e.g., filament transformer) with secondary/secondaries in series with mains to take away some voltage. This scheme entails kVA proportional to the voltage dropped (e.g., 12.6V) instead of the voltage supplied (e.g., 125), thus 10x less iron. It does not result in isolation, but isolation wasn't the stated goal.
