This model represents a three-phase unbalanced impedance with neutral cable. The current in the neutral cable is computed as the algebraic sum of the currents of the loads. The model extends from BuildingSystems.Electrical.AC.ThreePhasesUnbalanced.Loads.BaseClasses.Impedance_N and uses the load model from the package BuildingSystems.Electrical.AC.OnePhase.Loads.Impedance. The model computes the voltages, currents and powers on each phase.