Electrical Outlets - Click Here For Full Article

What Are Electrical Outlets?

The most common format of electrical outlets (also called receptacles or “plug-ins”) is two outlets per faceplate, mounted in walls about a foot or so from the floor or countertops. Outlets are used to power everything from lamps to computers to major appliances.  Not every outlet is the same, and if they are not properly installed, they can lead to serious electrical problems. It’s important to make sure that each outlet is wired correctly, with appropriate protective features.

How Do They Work?

The majority of electrical outlets follow the same design.  Two vertical inputs connect both a hot wire (the smaller input) feeding current from the electrical panel, and a neutral wire (the wider input) returning current back to the panel.  A third, rounded input below provides a grounded connection to protect from the chance of shock.

What Is Reverse Polarity?

Because an outlet is wired to have one hot input and one neutral input, it is important that the wires are connected properly. If the hot and neutral wires are incorrectly connected to the opposite inputs, reverse polarity occurs. This means that whatever device is plugged into the outlet is constantly receiving power, which can lead to injury or electrocution, even if the device is switched off. Because the problem is invisible to the naked eye, all electrical outlets should be tested by an inspector for reverse polarity.

Why Should Electrical Outlets Be Grounded?

Older homes (pre-1965) typically feature more two-input, non-grounded outlets, identifiable by their lack of a third input. The ground wire input was added to outlets to protect from electrical problems that can occur inside a plugged-in device or appliance.  For example, if the wiring inside an appliance becomes loose and makes contact with the casing, that device could shock anyone who touches it.  If the outlet was properly grounded, the current would instead be directed back to the ground input, protecting the person.

How Can You Be Sure Electrical Outlets Are Grounded?

Because three-input outlets are now more common in hardware stores, many non-grounded outlets have been replaced with three-input outlets.  However, unless outlets are tested, there is no way to know if the ground wiring has actually been connected.  Be sure to have all outlets tested by an inspector before assuming outlets are properly grounded.

What Are GFCI Electrical Outlets?

GFCI (Ground Fault Circuit Interrupter, sometimes referred to as GFI) outlets are usually found in kitchens, bathrooms, and other wet locations.  They are designed to protect the homeowner from a ground fault, or shock.  Ground faults come from an unintentional imbalance between the amount of current flowing between the hot and neutral inputs.  GFCI outlets protect by monitoring the current for an imbalance and tripping the circuit if they detect one.  This stops the flow of power to the outlet, preventing severe shocks, burns, and electrocution.  Because of this added protection, GFCI outlets are also a good choice to replace non-grounded outlets in areas that are difficult to rewire.

What Is AN AFCI Breaker?

While not an outlet, an AFCI (Arc-Fault Circuit Interrupter) breaker can also be installed to help protect a house from electrical fires.  Typically, when a hot wire makes contact with a ground or neutral wire, the current draw will be enough to trip the breaker on the electrical panel.  But if that contact is intermittent, due to loose, corroded connections or failing insulation, an electrical arc may develop.  This electrical arc can generate enough heat to cause a fire; in fact, more than 40,000 home fires per year are associated with electrical arcs.  An AFCI breaker will detect the electrical wave that an arc generates and trip the circuit to protect the home.