Is there any difference? I have been thinking about this to the point of confusion. Basically I have a delta 120/208 3 phase service at the shop and we work at a place with 277/480 a lot. I have a test box to connect motors and such and it's crude at best having just a breaker and motor starter. The problem is that the coil for the motor starter is 120. At the shop I just hook one wire to one phase and the other wire to the neutral, being 120/208, it gives it 120. At the other place, I'm obviously screwed. The plan is to use a transformer to make it work. Now the other thing is that the shop has a wild leg on that delta, so I have to be careful when I am aiming for 120.. I guess its 208 on the wild leg and 240 between each phase. Since each phase is the same voltage be it at the shop or at the other place (all are 240 P-P or 480 P-P), why can't I just run 2 phases into an autotransformer and ditch the neutral issue altogether... 2:1 setting for the shop and 4:1 at the other place. But is it that simple? I keep wondering if the 120* phase angle between phases will mess with it since phase to neutral is 180*. Am I wrong here? Am I just thinking too much? Thanks guys.