Determine the appropriate Miniature Circuit Breaker (MCB) rating based on electrical load and voltage.
MCB (Miniature Circuit Breaker) is a protective device used to automatically disconnect electrical circuits in case of overload or short circuit. Proper sizing ensures safety and prevents electrical hazards.
Current (I) = Load (W) ÷ (Voltage × Power Factor × √3 for three-phase)
For single-phase, I = Load ÷ Voltage
Select MCB rating slightly higher than calculated current using standard ratings: 6A, 10A, 16A, 20A, 25A, 32A, 40A, 50A.
Single-phase room with total load 2500 W at 230V:
I = 2500 ÷ 230 ≈ 10.87 A
✅ Recommended MCB size: 16 A
To protect wires and devices from overcurrent and prevent fire hazards.
Yes, multiply kW × 1000 to convert to watts before calculation.
Yes, three-phase systems divide load across phases and include √3 factor in current calculation.