When having a 3-phase system with neutral/GND, the measured voltage between any 2 phases (line voltage) is √3× the measured voltage between any phase and neutral/GND (phase voltage).
In this circuit, L1>N, L2>N and L1>L2 voltagemeters are shown in the waveform graph.
Now there can be seen why the measured voltages differ from each other.
In this case, the phase voltage is 230VAC RMS and the line voltage is 398VAC RMS.
When pausing, in the waveform graph the exact time stamp can be selected.
When selecting 563V on the orange waveform (398V RMS) the blue and green voltages show 281V (198,7V RMS) and -282V (-199,4V RMS) respectively. 198,7V and -199,4V add up to 398,1V
