GFCI Outlet Wiring Diagram

The pic below shows the electrical outlet GFCI wiring diagram and step how to wiring multiple outlet gfci  (round-fault circuit interrupter) with color code


What is GFCI Outlet ?


What is GFCI so it means “ground-fault circuit interrupter” which works mainly as to protect human or device also from connected to electric shock from electrical power. It is also called Residual Current Device (RCD) that shuts off an electrical power circuit detecting that undesirable path is following by electricity like through water or any living thing.

Also we have to define GFCI from NEC as “a device or instrument as shown below works for protection of any connected personnel which disturb the function of electricity to some circuit or another device”.


Purpose of GFCI :


Ground Fault Circuit Interrupter GFCI is a device which secure person from electric shocks from faulty currents in the electrical devices we use in our daily lives. It works by comparing the input current on the ungrounded side (red-wire) to the output current on the neutral side (black-wire).


GFCI Outlet Wiring Diagram :


In the GFCI mainly two wires connect as also shown in a diagram, the current flowing from the source and coming back are some due to current laws. So GFCI designed as checking the difference between the current leaving and returning through current transformer of the GFCI to protect device exceeds 5mA. The wiring diagram also shown below as follow;

gfci outlet wiring diagram electrical installation colo code


This shows 2-wire 14 gauge cable with grand wire having supply of power supply and connected GFCI. So, the solid-state-circuitry opens the switching contacts and de-energizes the circuitry as shown in the figure2 also. This will happens when GFCI is in on-conditions and when it fails to work the switching contacts remain closed and the device still giving the power with zero protection as to us. So also dangerous when fails. While damages occurs from voltage sparks from lighting and other transients.

 GFCI and light switch Wiring Diagram :


We are now studying wiring of GFCI and how it connects to light the bulb as also shown in figure below

gfci outlet electrical wiring diagram with light 2 way switch


SO there is a power supply supplying power to the circuit while black wires shows ground currents and white shows the non-grounded wires or called HOT wires. While green wires are for removing faulty currents to ground for device protection. As 2-wire cable with ground connect to the other side of GFCI so connected both the protective sides of GFCI to the device for protection of both a device and a person using it from any circumstances and shock from electricity as shown above in the figure above.

Multiple GFCI Outlet Wiring Diagram :


We have two types of wirings as single wiring as discussed above and another one is multiple GFCI wiring and we also attach the diagram to show how the wiring is done by designer or electrical engineer.

multiple gfci electrical outlet wiring diagram



We applied power supply either 230V/50Hz or 120V/60Hz where white is neutral and black is called “Hot” wire or calls non-grounded wire which connected to one terminal of GFCI while earthed-ground also shown in green wire which will protect our device from any non-relevant faults from power supply as given. GFCI is able to measure the fault current and sense the ground fault which is actually interrupted by GFCI.

Multiple GFCI  Outlet Wiring Diagram :



multiple gfci outlet wiring diagram electrical




The above diagram shows the GFCI wiring to Multiple Outlet as in white while the pictures are same.  One side of the GFCI connected to the ground (neutral wire as shown white in the diagram) and another side to the high potential (hot wire shown as black in the diagram) shows as in black color.  The socket of GFCI indicates as one pair in each for protection of any circumstances because of any switching-impulse withstand voltage or any switching-impulse withstand voltage while the timing for short-duration power frequency withstand voltage is from zero to 60 seconds. 


Conclusion on GFCI protection:


Press the test feature of the GFCI protection device to ensure it works. These are excellent devices when properly wired. However, never assume a GFCI protection device is operational unless you test it. The good process is to check a GFCI is to use a circuit tester that has its own GFCI test button and plug in the tester and push its test button. If the power goes off, the GFCI is working. Press the reset button to restore power as shown in figure1 also.

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