Charging a vehicle requires the correct voltages between the phases and neutral (L-N ≈ 230V).
The voltages between the phases cannot be over 400V. It is important that this is taken into account.

For IT grids, one of the phases can be used to replace the neutral if this is not supplied from the grid.
In this situation, charging on 3 phases is no longer possible. 
 
Also pay attention to the 'StrictPEMeasurement' configuration parameter when setting up the charging station.
The value will then be 'True' by default. For IT grids and other power grids without neutral, we advise to set these to 'False'.