When selecting an MCB for a three-phase system, consider:
- Current Rating: Ensure the MCB’s current rating matches or slightly exceeds the maximum current expected in the circuit it protects.
- Breaking Capacity: Choose an MCB with an adequate breaking capacity to safely interrupt the maximum fault current that could occur in the circuit.
- Tripping Curve: Select the tripping curve (e.g., B, C, or D) based on the type of load and expected inrush currents to avoid nuisance tripping.