Understanding 240/250-Volt Air Conditioner Outlets Nov 30, 2021Outlet Wiring for Air Conditioner Circuits . In a 2-wire cable for a 120-volt circuit, the "hot" current is carried by the black wire, while the white wire is the neutral. However, in a 240/250-volt circuit, there is no traditional neutral, since both wires are each carrying 120-volts of [PDF] Electric Vehicle Charging Station Installation Guidelines: volt household outlet or install a 240-volt circuit for faster charging. PEVs come with a 120-volt charging cord that enables owners to charge their vehicle with a conventional outlet (Level 1 charging). This is a very practical solution for owners of plug-in hybrid electric vehicles at (PHEVs), such as a Toyota Plug-in Prius or Chevrolet Volt.