Question

In a three phase four wire unbalanced system, the current in the neutral wire is 18 A. The magnitude of zero sequence current is
1. 18 A
2. 6 A
3. 9 A
4. 3 A

Answer 1

Correct Answer - Option 2 : 6 A

In a 3-phase 4 wire unbalanced system, the magnitude of the zero-sequence component is one-third current in the neutral wire.

Given that, the current in the Neutral wire = 18 A

∴ The magnitude of zero sequence current \(= \frac{1}{3}\) × current in the Neutral wire

\(= \frac{1}{3} \times 18 = 6\;A\)