Nothing to do with phase rotation. You could just swap two phase connections which would allow either direction. Anyway, usually there is a gearbox in there anyway, and nowadays most machines are interfaced through power electronics which allows rotation either way in theory.
It'll just be convention. Prop planes always rotate the same way, for (I guess) just to maintain convention. The blade manufacture is very expensive and it only makes sense to have one conventional blade mould or set of parts. If you made some turbines one way, some the other, then you need two whole sets of symmetrical parts and mounds, whereas when they all go the same way you only need one set. Cheaper, less stock to carry, less chance of mess-ups!
Dr. Andrew Roscoehttp://personal.strath.ac.uk/andrew.j.roscoe