Interrupt excess current to protect wires and equipment.
Fuses melt when I²t exceeds their rating; breakers trip thermally and magnetically and can be reset. Ratings: current, voltage and breaking capacity. MCB, MCCB, RCBO types. Coordination ensures only the faulty branch trips.
A 16 A MCB protects a 2.5 mm² ring circuit.
Fuses and breakers stop excessive current from overheating wires, which is a key safety function in any installation.
Interrupt excess current to protect wires and equipment.
Fuses and breakers stop excessive current from overheating wires, which is a key safety function in any installation.
A fuse melts and must be replaced, while a breaker trips and can be reset. Both interrupt excess current.
The fuse must trip before the wire overheats, so its rating must be below the cable's safe current carrying capacity.
Typical applications include choosing a fuse for a 13 A appliance circuit, sizing a breaker to protect a long cable run and selecting a fuse rating for a battery power line in a vehicle.
Study "Safety and grounding" first (topic 23 of 106 in Electrical Engineering). It covers the groundwork this topic builds on.
Time-current curves. Type B, C, D tripping. Protect wire, not the load.
A 16 A MCB protects a 2.5 mm² ring circuit.
The next topic is "Measuring instruments", which builds directly on this one.
It is classed as Beginner in Electrical Engineering (topic 24 of 106). It is an entry-level topic. It relies only on basic school mathematics and the ideas introduced earlier in this discipline.
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