Fuses, like circuit breakers, are designed to protect electrical wiring in San Jose by interrupting excessive electrical currents caused by, among others: overloaded outlets, malfunctioning devices, and short circuits. Though they may be rather simple things, fuses provide a very important service. Here’s a look at how they work.
How Fuses Work
Like the filament in an incandescent light bulb, fuses have thin wires that electricity can flow through. These 
wires are designed to carry a specific amount of electricity safely—the thicker the wire, the higher the current it can support. When an excessive electrical current attempts to pass through this wire, it heats up the wire to the point of melting or burning. This destroys the wire and interrupts the circuit. In the case of burning, the wire gets very hot very quickly, and it blows out, producing a loud and characteristic popping sound. When a fuse is blown, it needs to be replaced.
Which Size to Use
Fuses come in a range of sizes and amperages. Generally, you want to replace a blown fuse with one that has a similar rating—i.e. a five-amp fuse with a five-amp fuse. If you’re not sure which kind of fuse to use, you can use your discretion based on logic. Since large appliances and devices tend to need more electricity to operate, they most likely require larger fuses. Likewise, smaller devices require smaller fuses. If you’re uncomfortable making a decision, contact a qualified electrician for assistance. Using a small fuse for something that draws a large current will blow out the fuse quickly. Using a large fuse for something that draws a small current will overwhelm it and can cause a dangerous situation.
How Fuses Differ From Circuit Breakers
Both fuses and circuit breakers protect homes from electrical mishaps. Unlike fuses, circuit breakers have reusable mechanisms that, when tripped, cut-off power to outlets. These mechanisms can be easily reset once they are tripped. Circuit breakers can also be used in conjunction with ground-fault circuit interrupters (GFCI). Fuses are the more economical choice of the two. They are more sensitive than circuit breakers, which may or may not be useful depending on their application. They also tend to be more prominent in older homes.