What prevents excessive current in a circuit?

What prevents excessive current in a circuit?

• A. Fuse
• B. Ground Fault Interrupter
• C. Circuit Breaker
• D. Ohm

Answer: (A)

Overcurrent protection is about stopping more current than a circuit can safely carry. A fuse does this by containing a metal link that melts when the current exceeds its rating, opening the circuit and cutting off flow to prevent wiring from overheating or catching fire. It’s a one-time safeguard that sacrifices itself to protect the system, and once it blows, it must be replaced. A circuit breaker also serves overcurrent protection, but the fuse is the classic device designed specifically to interrupt current as soon as the limit is exceeded. A ground-fault interrupter protects against shock from a ground fault, not general overcurrent. Ohm’s law describes how current is determined by resistance, not a mechanism that prevents excessive current.

Overcurrent protection is about stopping more current than a circuit can safely carry. A fuse does this by containing a metal link that melts when the current exceeds its rating, opening the circuit and cutting off flow to prevent wiring from overheating or catching fire. It’s a one-time safeguard that sacrifices itself to protect the system, and once it blows, it must be replaced. A circuit breaker also serves overcurrent protection, but the fuse is the classic device designed specifically to interrupt current as soon as the limit is exceeded. A ground-fault interrupter protects against shock from a ground fault, not general overcurrent. Ohm’s law describes how current is determined by resistance, not a mechanism that prevents excessive current.