A: A GFCI (Ground Fault Circuit Interrupter) is designed to enhance personnel safety by detecting ground faults—small current imbalances between the hot and neutral conductors. If the GFCI senses a difference as small as 4 to 6 milliamps, it assumes current may be leaking through an unintended path (like a person) and immediately disconnects the power. This rapid response reduces the risk of serious electrical shock.
In contrast, a circuit breaker protects equipment and wiring by interrupting current flow when it exceeds a safe level. For example, a 5-amp breaker will trip if current rises above 5 amps, typically due to a short circuit or overload, preventing overheating and potential fire hazards. Unlike a GFCI, it does not detect small current leaks—it responds to excess current, not current imbalance.
These devices serve distinct safety functions: GFCIs protect people from electric shock, while circuit breakers protect electrical systems from damage due to overcurrent.