How do you calculate the line current in a star (wye) connection?

For a balanced three-phase system (equal loads and equal phase angles), the line current (I_L) can be calculated using the following formula:

I_L = √3 * I_Phase

where:

I_L = Line current (rms or peak value)

I_Phase = Phase current (rms or peak value of any one phase)

For an unbalanced three-phase system, you need to consider each phase's current magnitude and phase angle to calculate the line current. The line current will vary based on the degree of imbalance.

If you have the complex phase currents (phasors) instead of the magnitudes, you can sum up the three phase currents and convert the result back to the magnitude using the formula above.

Keep in mind that line current is the current flowing through each line (connection) in the system. In a star connection, there are three line currents, one for each line emanating from the common point.