In a triphasic system (any), is there a way to tell if the current is entering or leaving a phase/line/load just by the angle of the phasor of the source ?

In the following picture we can see the labels IA, IB and IC. They all point towards the load.

But we know that it's not the actual current direction

What is their actual direction when VAB=380<0, VBC=380<-120 and VCA=380<120 ?

Can I tell this by the angle ?

Star Load

As can be seen by this graph, when two curves cross, two currents are leaving the load, while another one is entering. 60 degrees later, in any direction, the reverse occurs.

Phase Graph

  • \$\begingroup\$ If there is no load, there is no current and if the load also has a bigger source then the current would be reversed . right? regardless of number of phases \$\endgroup\$ Nov 27, 2019 at 18:59
  • \$\begingroup\$ Current entering or leaving can only be defined for a specific instant in time. Phasors represent RMS or peak values of voltages and currents and complex impedance values and the phase relationships among the values, but not values at a specific instant in time. The source voltage and current phasors will show whether the source is supplying or absorbing power on average, but not instantaneous energy flow. It is not really clear what you are asking. Voting to close. \$\endgroup\$
    – user80875
    Nov 27, 2019 at 20:18
  • 1
    \$\begingroup\$ If the current is alternating then by definition it will alternately enter and leave. \$\endgroup\$
    – Transistor
    Nov 27, 2019 at 22:20
  • \$\begingroup\$ Yes, but which one is entering and which one is leaving at a given moment ? \$\endgroup\$
    – Lucas BS
    Nov 29, 2019 at 14:49


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