Ground Fault Circuit Interrupter (GFCI) Wiring Diagrams

by: Dale Cox

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How to read these diagrams.

This page contains wiring diagrams for ground fault circuit interrupter (gfci) receptacles. Included are diagrams for multiple gfci's, a protected standard duplex receptacle, and a protected light fixture. Wiring for a switch and gfci receptacle in the same box is also shown. To wire a gfci circuit breaker see this link and wire a gfci switch combo at this link.

Wiring a GFCI Outlet and a Light Switch

wiring diagram for a gfci outlet and light switch in the same box

This diagram illustrates wiring a GFCI receptacle and light switch in the same outlet box, a common arrangement in a bathroom with limited space. The hot source is spliced to the LINE terminal on the receptacle and to one terminal on the light switch. The neutral and ground wires are spliced together and run to each device in the circuit. This wiring provides single-location gfci protection. The light and switch are not protected by the gfci receptacle.

Wiring GFCI Receptacles with a Protected Outlet

gfci outlet wiring in a series with a protected duplex receptacle at the end

This gfci wiring provides protection to a duplex receptacle outlet at the end of the series. By connecting the load terminals on the last gfci, the wall outlet at the end is protected and can be used just as if it were one of the gfci receptacles. One ground fault circuit interrupter at the beginning of the circuit can be used in the same way to protect multiple, subsequent wall outlets in a row as illustrated in the next diagram below.

wiring diagram of a gfci receptacle to protect multiple duplex outlets

GFCI Receptacles in a Series with an Unprotected Outlet

wiring multiple ground fault circuit interrupter

This diagram illustrates the wiring for multiple ground fault circuit interrupter receptacles with an unprotected duplex receptacle at the end of the circuit. The load terminals on the gfci are not used and the last receptacle is wired directly to the circuit source. With this wiring each gfci provides single-location protection and the last outlet in the series is not protected from ground faults.

GFCI Outlet Wiring to Protected a Light

diagram for gfci outlet wiring with a protected light and switch

This diagram illustrates the wiring for a circuit with 2 gfci receptacles followed by a light and switch. By connecting the switch to the load terminals on the last gfci, the switch and light are protected against ground faults as well. This gfci wiring method may be found in a bathroom or kitchen where the switch may be near a water source.

GFCI Wiring Method with an Unprotected Light

gfci wiring diagram with a light and switch not protected from ground faults

This diagram illustrates the wiring for a circuit with 2 gfci receptacles followed by an unprotected light and switch. The light switch terminal is connected directly to the source coming from the circuit. Using this wiring method, the light circuit is not protected from ground faults.