If you have standard three-phase already (4-wire wye) and power supplies that support 208 volts, you should be able to use L1 & L2, L2 & L3, or L1 & L3 to the power supply. If you have a three-phase delta (480 volts), you'll need a step-down transformer to 240 volts (or 120 volts).

Most power supplies support a range of voltages, for example one I have here is 110-120 volts & 200-240 volts compatible. Others I've seen are 100-250 volts.

Feel free to post the power supply make & model and we should be able to figure it out.