The Lenovo Flex System chassis efficiently uses 200 - 240 V ac, three-phase, data center power. Each chassis can contain up to six, single-phase power supplies, which you can connect to single-phase or three-phase power distribution units (PDUs). Depending on the three-phase PDU that you use, you can connect one or two power supplies to each phase to evenly balance the load.
For more information about power requirements and considerations, see the Lenovo Flex System Enterprise Chassis Features and Specifications section, the System x Power Configurator site and the documentation that comes with your PDUs.