Fuses and circuit breakers are two different ways of protecting against suddenly large overloads of electrical flow. Large power overloads are dangerous, potentially destroying electrical equipment or causing a fire. Both fuses and circuit breakers will automatically block against an incoming surge of electrical power past a certain safety limit. But while they both accomplish the same task, each uses different technology in the way that it stops the flow of electricity.

Fuses are typically small objects that plug into a fusebox or other central location. They are an early technology, dating back to the 19th century. Inside the fuse is a small piece of metal, across which the electricity must pass. During normal flow of electricity, the fuse permits the power to pass unobstucted. But during an unsafe overload, the small piece of metal melts, stopping the flow of electricity. When a fuse is tripped, it should be thrown away and replaced with a new fuse. As there are many varities of fuses available that handle different capacities of electricity, care should be taken when choosing replacement fuses.

Circuit breakers are a more recent invention and improve on fuse technology. Circuit breakers are switches that are tripped when the electrical flow passes a safe limit. The excess of electricity typically triggers an electromagnet, which trips the circuit breaker when an unsafe limit is reached. Once tripped, the switches simply turn off. That stops the flow of electricity, which will remain off until the switch is reset. To reset the flow of electricity after the problem is resolved, the switch can simply be turned back on. Circuit breakers are often located in a cabinet of individual switches, typically inside of an apartment or other central place. While often used in homes, circuit breakers can be used for much larger industrial applications as well.

Fuses and circuit breakers have unique advantages and disadvantages. One advantage of fuses is that they are cheap and can be purchased from any hardware store, but they have the drawback of needing to be replaced once they stop an overload. That can be challenging in a darkened room. Alternatively, circuit breakers can simply be reset with a flip of a switch after an overload. However, the technology can be more expensive than a fusebox. Electricians are best qualified to determine whether fuses or circuit breakers are better for a particular electrical installation.