Ground Fault Circuit Interrupter Gfci Definition

It works by comparing the amount of current going to and returning from equipment along the circuit conductors.

Ground fault circuit interrupter gfci definition. Let s end the confusion with the definition and description of ground fault and ground fault circuit interrupters gfi gfci. A residual current device rcd residual current circuit breaker rccb or ground fault circuit interrupter gfci is a device that quickly breaks an electrical circuit to prevent serious harm from an ongoing electric shock. Gfci s could also reduce electrocutions and minimize electrical burns and shock injuries. Their circuitry monitors electrical input.

When a ground fault occurs the gfci quickly in a fraction of a second shuts off the power. There is a class a gfci that trips when a ground fault current exceeds 5 milliamps and there is a class b gfci that trips when a ground fault current. Now thanks largely to the proliferation of gfci technologies particularly in areas near water such as bathroom sinks or in places exposed to rain or standing water that number has dropped to around 200. Because of this we need to understand what a gfci is how it works and what its limitations are.

A ground fault circuit interrupter is an electrical device installed to protect against severe electric shocks. We need only to look to the nec for the definition of a gfci. Ground fault circuit interrupters gfcis or gfis are safety devices built into outlets that protect against electrical shock. A ground fault circuit interrupter gfci or residual current device rcd is a type of circuit breaker which shuts off electric power when it senses an imbalance between the outgoing and incoming current.

A ground fault circuit interrupter gfci is the only protection device designed to protect people against electric shock from an electrical system. Injury may still occur in some cases for example if a human falls after receiving a shock or if the person touches both conductors at the same time which an rcd won t. The main purpose is to protect people from an electric shock caused when some of the current travels through a person s body due to an electrical fault such as a short circuit insulation. The ground fault circuit interrupter or gfci is a fast acting circuit breaker designed to shut off electric power in the event of a ground fault within as little as 1 40 of a second.

Before the widespread adoption of gfci ground fault circuit interrupter outlets around 800 people died annually in the united states.