When a 3 phase system is balanced, what will be the current in the neutral wire ?

By Nirmal -
Neutral is the point at which all the three phase’s current meets and the algebraic sum of current becomes zero in case of “Balanced Load Condition”.

I = I1 + I2 + I3 = 0

When ALL phase has balanced load, neutral should be ZERO volt in respect to earth. Be careful the word “Balanced”, which means, if there is an unbalanced phased (due to load), the neutral will no longer be ZERO volt in respect to earth. When there is more than ZERO volt between neutral and earth, then there will be current flow through these 2 points (Leakage Current).

Even for most of the time, neutral and earth has ZERO volt between them; they should never be connected together or be used interchangeably.

Neutral: Return path of current flow in order to make a closed circuit [Return Path Conductor].

Earth: Path for Leakage current [Short Circuit / Fault Current / Crack in Insulation] in the circuit to protect Human & Equipment Safety.

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