Helpful Electrical Terms – Daniel Electric – Southlake, TX
The ground leg, the third round leg on most power cords, is designed for safety. Many appliances, such as computers, are encased in metal. If the case is not properly grounded and an electric short occurs in the appliance, it is possible for the case to become electrically charged. The ground provides a path for electricity to travel safely out of the house and into the earth in an emergency.
Breaking off the ground leg on a power cord is dangerous. By breaking off the ground leg, the homeowner typically assumes all liability for the appliance or product and voids all manufacturers’ warranties.
Ground fault circuit interrupters (GFCIs), designed to prevent people from receiving electrical shocks, can be installed at an individual outlet or in the service panel. When properly installed in a circuit, a GFCI continuously monitors the current flowing in both lines in the circuit. If the GFCI detects a short circuit developing, it quickly interrupts the circuit before anyone is seriously injured.
GFCI protection is provided either by special GFCI outlets or by special GFCI circuit breakers. Depending on how a GFCI outlet is wired, it may protect either that outlet only or all the outlets downstream from it. GFCI circuit breakers protect the entire circuit. The National Electric Code requires GFCI protection on all new outlets located outside of the house, in bathrooms, in garages, in basements, and within six feet of the kitchen sink. Identifying a GFCI outlet is simple. GFCI outlets have two buttons on the face, one labeled “test” and one labeled “reset.” Both GFCI outlets and GFCI circuit breakers should be tested often to ensure proper function.
An arc fault circuit interrupter (AFCI) is a relatively new type of breaker designed to detect and stop arcs. Arcing wires are responsible for numerous fires each year, because they generate hot sparks. These fires are especially common in bedrooms where dressers and beds are pushed up against plugs inserted into wall outlets. Over time, the plug and/or the insulating casing surrounding the wire may crack or fray, thus exposing bare wires and creating an arc. Additionally, by chewing on electrical cords, family pets sometimes expose bare wires. Since 2002, AFCIs are required on all new construction.
Many older homes have systems that lack grounding wires or have wiring designed to carry smaller loads of electricity, which can be incompatible with the demands of today’s electrical devices. While older electrical wiring can remain safe for decades, it is a good idea to have an older system inspected by an electrician. If it is necessary, updating wiring can make a home safer, bring the wiring up to current codes, increase voltage capacity, and in some cases bring down home insurance rates. Since rewiring requires access to every outlet and the insides of many walls, many homeowners find it convenient to update their wiring during home remodeling projects.
Many homeowners install backup generators that run on natural gas, propane, gasoline, or diesel to provide their homes with electricity in the event of a power outage. Electricians typically sell and install these systems. Before purchasing a system, you should clearly define how you plan to use it.
One issue to consider is how much of your home you would like or need to use when the power is out. A lower-cost option might provide only enough electricity to power the refrigerator and a few lights, while a more expensive option may provide enough electricity to power the whole house, including the air conditioners. Before purchasing a generator, add up the power requirements of the appliances and fixtures you intend to operate, and then buy a generator that is sized appropriately.
Another important decision is whether to purchase an automatic or a manual generator. While more expensive, the automatic option senses the loss of power from the public utility, automatically starts the generator, and automatically switches the home’s load to the generator. The manual option often requires the homeowner to wheel the generator out, plug it into the home’s wiring, start it, and manually switch the home’s electrical load to the generator.
All backup generator options that supply electricity through the home’s wires require the installation of a transfer switch. As the name suggests, the transfer switch transfers the home’s load from the public utility to the generator and back ‘again. Because an improperly installed transfer switch could allow electricity to back feed into the utility lines, which could potentially electrocute a utility worker, only qualified electricians should install transfer switches.
Power surges may result in damage to electrical devices within the home. Many homeowners choose to install surge protectors, which regulate the voltage supplied to an electronic device by diverting excess electricity through a grounding wire. Common plug-in surge protectors plug into a single wall outlet and feature a hub into which several electronic devices can be plugged, offering moderate protection to those devices. Whole-house units, which protect all electric devices within the home, are also available. These are installed by an electrician at the meter or at the service panel. A whole-house unit monitors voltage levels entering the home. Whole-house units only protect from incoming surges.
CITY ELECTRICAL INSPECTORS
City electrical inspectors typically inspect installations requiring a building permit, like new construction, room additions, and so on.