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How To Wire Up A GFCI Plug

How To Wire Up A GFCI Plug

This article will help you understand how to wire up a gfci plug. It is important to get the line and load correct to make it work properly.

On the back of the gfci there is a line and a load. The terminals are marked clearly at line and load. Do not get these incorrect. The gfci will not work at all if this is done. Generally all gfci outlets are clearly marked on the back as to what color wires go where.

In the event that it is wired incorrect the outlet may still light up but not work.

How To Wire Up A GFCI Plug?

Wiring up a standard GFCI receptacle is pretty straightforward. On the back of the GFCI receptacle you will see it has a line in a load. It is clearly marked line and load.

It is also marked hot and white wire. If you have a two wire feed inside of the box then you will simply follow the instructions connect the black to the hot wire and the white to the white neutral wire.

The bare copper wire will get terminated under the green ground screw. We can then re-install the new GFCI receptacle inside of the wall box.

You will need to hit the reset button once this is installed. GFCI outlets will not reset until they have power for the first time.

How Do You Wire A GFCI Plug With 4 Wires?

Installing a GFCI receptacle with four wires simply means we have a line in a load.

If you look at the back of the wires you will see it is actually two conductors. There will be a power feed coming from the panel and the other will be going out to something else.

It gets important at this point to get the line and load correct.

If you get the line and load backwards the GFI will simply not work. You can check which one is the line after you have the wire stick out of the wall.

We use a voltmeter to do this. It will read 120 volt across the line side of the power feed between white and black.

The load side should have no power at all. The load side is protected through the GFI. We call this down feeding.

You must follow the line and a load on the back of the GFI and you also must have the colors correct. It is marked right on the back of the GFI.

How Do You Wire A GFCI Plug With 3 Wires?

Wiring a GFCI plug with three wires just simply means there are three sets of two wires inside of the box.

The simplest form to wire this to the receptacle is to connect all three white wires together with a pigtail.

This means one coming out off of the whites. We will also do this with your blacks. Connect all three together and then have a black pigtail coming off.

This will leave you one black wire and one white wire. They should be connected to the back of the line side of the GFCI receptacle.

The bare ground wires should then be also connected together and a tail coming off of those as well.

We will then connect onto the green screw of the back of the GFCI receptacle with the bare copper wire.

Why Is The Line And Load So Important ?

The line and the load are extremely important to get correct on the back of a GFCI receptacle.

As mentioned above if we do not get these correct then the GFCI will simply not work.

The GFCI can fool you even if you have the line and load incorrect.

The green light on the GFCI will still light up fooling you into thinking that there is power inside of the outlet.

You’ll notice that if you check with the meter or try to plug something in there’s no voltage present.

What Is A Down Feed ?

A down feed is it feed that comes out of the load side of the GFCI. This actually protects anything on the load side of the GFCI by the GFCI.

It means that anything protected by the gfci will trip if it needs to. This includes moisture or a fault to ground.

We often installed this a newer homes to save on gfci receptacles. This saves money on the project overall and makes it simpler to know if you have a problem.

We can also install a gfci breaker right inside of the panel box. This protects the entire circuit. We often do this on outside outlets to save on cost. This also eliminates the issue of gfcis breaking or malfunctioning due to moisture.

How Many Devices Can I Install On A GFCI Plug?

You can actually install or protect whatever you like really by a gfci plug.

Light fixtures in bathrooms or damp areas can be protected as well. We often do this in areas of high moisture.

This is done by using the down feed side of the gfci outlet. You will want to be careful with motor loads though. The inrush current from a motor load will cause nuisance tripping.

This is usually caused by bath fans, living room ceiling fans etc.

Can You Split Wire A GFCI?

We can not physically split wire a a gfci outlet because the design does not allow it.

We can however install a 3 wire circuit in split one GFI on the red side 3 wire circuit and black side of the 3 wire circuit.

If you hook the gfcis up online side then you should not have a problem.

We don’t recommend that you down feed anything off of the GFI.

If you down feed anything this will cause nuisance tripping and the gfci will detect the unbalanced load.

How Do You Hook Up A GFCI To A Light Switch?

Hooking up a GFCI plug to a light switch is relatively easy. You will run a wire from your panel into the line side of the GFCI.

From the line side of the GFCI you will then run from the load side out to your switch. You can then terminate through this which as normal.

This will down feed the GFCI this will down feed the switch from the GFCI.

Does A Bathroom GFCI Need To Be On Its Own Circuit?

You are not required by code to have a GFCI receptacle in your washroom her bathroom.

However if you do install one then it states that it needs to be on a GFCI. Kind of a catch 22 but you cannot put a regular outlet in the bathroom.

This also means that you must try to remain 1 m or from anyone at water source with any additional outlets that you down feed from that GFCI in the washroom.

You should have it on its own circuit. This is due to using hair dryers and other women’s appliances.

They draw upwards of a total 15 amp circuit. You can also run A 20 amp T-slot GFI and install a 20 amp circuit if you need a heavier load.

how to wire up a gfci plug

How To Wire Multiple Outlets From A GFCI?

From the panel we will run a single 15 amp circuit of 14/2. From there you will go into the line side of the first GFCI.

We then can leave the load side of the GFCI and go to as many regular outlets as you would like up to 12 on that circuit.

This just simply protects the entire circuit through the first GFCI this is a common practice for larger areas that run into moisture or damp locations.

A good example of this would be a sunroom built on to the side of your house.

how to wire up a gfci plug

What Is Nuisance Tripping?

Nuisance tripping is called that for exactly that reason the GFCI continues to trip for no reason at all.

If the GFCI senses any moisture or damage or any unbalanced load in the circuit it will trip.

Sometimes vacuum cleaners will tripped GFCI‘s other times your outside cord for your Christmas lights will trip GFCI‘s.

No matter the appliance or the use it’s still becomes a nuisance when you’re continuously going to reset the GFCI.

Why Do Some GFCIs Have A Red Light And Some A Green?

GFCI receptacles are made by a number of different manufacturers.

Each manufacturer has its own specifications on what and how they would like the GFCI to work.

Some have a simple green light to show that the GFCI is working while others have a red and a green light to show you that the GFCI is either working or not working.

Hubble for example is a GFCI company that also makes devices and when the red light flashes on the GFCI. It states that it must be replaced this is a warning sign that it is actually time to replace it .

The gfci will not work when the light is flashing. You can find out more of gfcis and what we recommend here.

These are all factors and related to how to wire up a gfci plug.

More on gfcis here.


Will GFCI work if hot and neutral are reversed?

No, there are only two wires on a GFCI outlet. The hot wire goes to the line terminal black and the neutral wire goes to the line terminal white. If they are reversed it will simply not work an most likely damage the gfci.

Should GFCI be grounded?

No, this is not necessary. GFCIs do not need to be grounded in order to function properly. If fact we often install them in areas with wires that have no ground to bring it to code.

Where does the hot wire go on a GFCI?

When working with a GFCI, it is important to know where the hot wire goes.

The hot wire goes on the line terminal (the one labeled “line or hot”).

If we are connecting this outlet to an existing circuit, the bare wire will connect to the ground terminal and then go into the house wiring.

If we are adding this outlet to a new circuit, the gfci wiring will connect to the line terminal first and then go into house wiring at a junction box.

Can a GFCI work without a neutral?

A GFCI outlet is a device in your electrical panel that protects you from electric shocks. It’s very common for these outlets to be found where there is no ground wire, or where the wire needs to be replaced.

A GFCI outlet can not work without the neutral wire being connected to it, but it will not protect you from electric shock.

It would be best to make sure that each outlet on your circuit has a proper ground connection and the neutral wire is correctly connected.

The hope this article better helped you understand how to wire up a gfci plug.