vre,
The transformer is for getting 220V from 380V mains. The drives and the PC can run from 220V single phase, but I didn't want to introduce a neutral phase into the system to avoid line fluctuations. That's why the three phase transformer is there. Nut on my Z axis screw is single and on the x axis is double. No big reason behind that besides they were the only ones available at the time of assembly. For breakout boards I'll ask my friend Nooruddin, who did the electronics mumbo jumbo, for any tips.
Zafar