What is a Ground-Fault Circuit Interrupter (GFCI)?
A GFCI is a fast-acting circuit breaker that senses small imbalances in the circuit caused by current leakage to ground and, in a fraction of a second, shuts of the electricity. The GFCI continually matches the amount of current going to an electrical device against the amount of current returning from the device along the electrical path. Whenever the amount “going” differs from the amount “returning” by approximately 5 milliamps, the GFCI interrupts the electric power within as little as 1/40 of a second. The GFCI, however does not protect from line-to-line contact hazards (such as a worker holding two “hot” wires or a hot and a neutral wire in each hand). It does protect against the most common form of electrical shock hazard – the ground fault, and it also protects against fires, overheating, and destruction of insulation on wiring.
