Line or Load: A GFCI Connection Choice

Metal countertop and electrical outlet
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When it comes to ground fault circuit interrupter outlets, commonly known as GFCI outlets, there is always a question as to how to connect the wires to them. You see, GFCI’s have two terminals on each side, one side the neutral connection and the other the hot wire connection, and a ground terminal on one end. One-half of the outlet connection is labeled LINE and the other LOAD. To the unfamiliar eye, they appear to connect to the same point, and in fact, the terminal screws are the same color, giving the appearance that they are a common connection.

The truth is that these connections are very different and I’m going to tell you why. This is one of those times that you must read the directions first before connecting the wires, that is if you want the outlet to actually work.

The line connection is the point where you will connect the incoming feeder wire, the line, which is fed from the home’s electrical panel. You’ll connect the hot wire, often a black or red wire, to the brass-colored terminal screw or in the slot provided to accept the stripped wire. The neutral connection, white wire, is then connected to the silver-colored terminal screw or slot provided to accept the stripped wire. Be sure to tighten the terminal screws and tug on the wire to check that the connection is tight. These terminal screws are uncovered and visible right out of the manufacturer’s packaging. This is different from the load connection’s appearance.

The load connection is visible from the time you pull it out of the package.

There is a piece of tape that covers the terminal screws, often yellow in color. As with the line connection, when you look on the back of the GFCI, there is a labeled area designating the load connection. The load connection is available to feed addition regular outlets from the GFCI and have protection from the GFCI.

In other words, any regular outlet that is fed from the load side of the GFCI is also protected from a ground fault because of the GFCI. The benefit of this is to reduce cost by only having to purchase one GFCI when running addition outlets, instead of buying a GFCI for every outlet. The regular outlets are about 1/10th the cost. The downfall is that when there is a ground fault condition with any of these added outlets, the GFCI outlet then trips. It may be located close, but it may be quite a distance away from another room or outside. The inconvenience of having to go to another area to reset the GFCI may not be worth it. Then again, you may have no problem taking a short walk to save a few bucks.

The ground screw is always green and is located on one end of the GFCI. This is where the bare or green-colored ground wire is to be connected. This connection should be pig-tailed to a connection that is bonded to the junction box that it is being installed in. Be sure and connect all ground wires together to ensure that the grounding circuit is carried by the additional outlets for proper connection to all outlets.This grounding connection is an essential part of safety for devices attached to the GFCI outlet.

You must have a secure ground connection attached properly.

For protection in bathrooms, kitchens, garages, swimming pools, spas, whirlpool tubs, outdoor outlets and wet areas near water, GfCI outlets are there to protect you. Knowing a little more about how they are connected will ensure that you make the correct connections that will keep you and your family safe.