What is the CB needed for three phase 440V 50Hz at 161 KVA Power?

To determine the required circuit breaker (CB) rating for a three-phase system operating at 440V and 161 kVA, you can use the formula:

[ \text{Current (I)} = \frac{\text{Power (P)}}{\sqrt{3} \times \text{Voltage (V)}} ]

For 161 kVA at 440V, the current is approximately 210.5 A. It's common practice to select a circuit breaker with a rating higher than the calculated current to account for inrush currents and future expansion, so a circuit breaker rated around 250 A would be appropriate.