These connections do not supply split single-phase power, and do not have a high leg. Other types of three-phase supplies are wye connections, ungrounded delta connections, or corner-grounded delta ("ghost" leg configuration) connections. So if A-B, B-C and C-A are all 240 volts, then A-N and C-N will both be 120 volts, but B-N will be 208 volts. The remaining phase-to-neutral voltage will be √ 3/2 the phase-to-phase voltage. The phase-to-neutral voltage of two of the phases will be half of the phase-to-phase voltage. The voltages between the three phases are the same in magnitude, however the voltage magnitudes between a particular phase and the neutral vary. One transformer is connected to one phase of the overhead primary distribution circuit to provide the 'lighting' side of the circuit (this will be the larger of the two transformers), and a second transformer is connected to another phase on the circuit and its secondary is connected to one side of the 'lighting' transformer secondary, and the other side of this transformer is brought out as the 'high leg'. Another method (the open delta configuration) requires two transformers. One is by a 3-phase transformer (or three single-phase transformers), having four wires coming out of the secondary, the three phases, plus a neutral connected as a center-tap on one of the windings. High-leg delta service is supplied in one of two ways.
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