[Milsurplus] transformer

[Brad Latta]

 Hi all,
            I am building a 28V, 50A power supply. The transformer I have was a three phase 208Vac delta input , 20Vac star output. I am hoping to connect the input winding to the single phase 230Vac mains here, I seem to remember a circuit for converting three phase connections to single phase, but cannot locate it. It's for a mil project. Does anyone remember the circuit?
             Regards, Brad