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Circuit breaker ratings

Standard breaker ratings (6–63 A), B/C/D tripping curves and selection by load type.

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Standard ratings

Circuit breakers come in rated currents: 6, 10, 13, 16, 20, 25, 32, 40, 50, 63 A. For household wiring, 10, 16, 25, 32 A are most common.

Tripping characteristics

TypeInstantaneous trippingApplication
B3–5 × InLighting, sockets (resistive load)
C5–10 × InMotors, air conditioners, washing machines, fridges
D10–20 × InTransformers, large motors, welding equipment

Rating by power

LoadPowerRecommended breaker
Lightingup to 2.2 kW10 A (B)
Socketsup to 3.5 kW16 A (B)
AC / washing machineup to 2.5 kW16 A (C)
Stove / ovenup to 6 kW32 A (B/C)
Main supplyup to 7 kW32 A
Main supplyup to 11 kW50 A (or 3-phase)
Rule: a breaker protects the cable, not the appliance. The breaker rating must not exceed the cable ampacity.

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Data is for reference. Final design decisions must follow current regulations and a qualified engineer.