What is the purpose of a ground fault circuit interrupter (GFCI)?

The purpose of a ground fault circuit interrupter (GFCI) is to prevent electric shock by interrupting the circuit when a ground fault is detected. A ground fault occurs when there is an unintended path between the source of current and the ground. This can happen in various situations, especially in wet environments such as kitchens, bathrooms, and outdoor locations, where the risk of electric shock is higher due to the presence of water.

A GFCI monitors the electrical current flowing through the circuit and can detect imbalances between the current entering and exiting the device. If it senses that the current is deviating from the normal flow—which suggests that some of the electricity is escaping to the ground—it quickly cuts off the power to the circuit, thereby significantly reducing the risk of serious injury or fatal electric shock.

This safety feature is a crucial aspect of electrical systems in residential, commercial, and industrial settings, ensuring that individuals are protected from the hazards associated with ground faults.