Here you see that the voltage between two phases of 133 V and 120° lag, and 1 phase of 230V will result in the same voltage. Phase 1 and 2 each have 133 V (measured between phase and neutral), phase 2 lags 120° behind phase 1. Phase 3 has a voltage of 230 V (measured between phase and neutral). The voltage between phase 1 and 2, and between phase 3 and neutral will both be 230 V.
