split charge system

A split-phase or single-phase three-wire system is a form of single-phase electric power distribution. It is the alternating current (AC) equivalent of the original three-wire DC system developed by the Edison Machine Works. The main advantage of split-phase distribution is that, for a given power capacity, it requires less conductor material than a two-wire single-phase system.
Split-phase distribution is widely used in North America for residential and light commercial service. A typical installation supplies two 120 V AC lines that are 180 degrees out of phase with each other (relative to the neutral), along with a shared neutral conductor. The neutral is connected to ground at the transformer's center tap.
In North America, standard household circuits for lighting and small appliances are connected between one line and the neutral, providing 120 V. Higher-demand appliances such as ovens, dryers, or water heaters are powered by 240 V circuits, connected between the two 120 V lines. These 240 V loads are either hard-wired or use outlets designed to be non-interchangeable with 120 V outlets.
Split-phase systems are also used in some specialized applications to reduce the risk of electric shock or to minimize electromagnetic noise.

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