House Wiring Components
Some home improvement and repair jobs may involve the electrical system. Working with electricity can be dangerous and major projects should be handled by trained professionals, but many minor repairs can be safely tackled by amateur handymen as long as they observe basic electric safety protocols. All homeowners would benefit from having at least a rudimentary understanding of what components make up their home's electrical wiring system.
Circuit Breaker Panel
The main electrical line feeds from the power line into the home's circuit breaker panel box. The breaker panel typically is divided into two sections. One section houses the main breaker, which supplies power to the entire home. The other section divides the power between a number of different circuit breakers, each of which is rated at a specific load, such as 15 amps or 20 amps. Circuits that will be drawing more power, such as those that feed an electric range, clothes dryer or HVAC system, require circuit breakers that can handle the greater amounts of current that are required to power these appliances. This dual section configurations allows the homeowner or repair person to cut the power off to the entire house, or to cut the power only on the circuit that needs repair.
Electrical wiring used in homes is specified by local and national building codes. Homeowners should check with their local codes department before making any repairs or additions to their home wiring scheme in order to ensure they are in compliance. The National Electrical Code requires electrical wire that is used in homes to be both protected and enclosed. Home electrical wire is commonly referred to as ROMEX®, and comes in a number of configurations, depending upon the purpose for which it is being used. The version of 14-2 ROMEX® is suitable for standard electrical outlets and lighting. Three-way light switches require 14-3 ROMEX®. Garages and kitchens typically use 12-2 or 12-3 ROMEX®, which may use appliances that draw more power. Circuits used for heavy duty appliances such as clothes dryers or electric ranges will require 10-3 or 8-3 ROMEX®, depending on the amperage they require.
Electrical outlets, or receptacles, are the means that allow home occupants to tap into the home's electric power for items that do not need constant power, or that might need to be moved, such as lamps, small kitchen appliances, hair dryers and vacuum cleaners. Some older homes may have old-style Type A receptacles that have two slots for plugs. Homes built since the 1970s use the newer Type B receptacles, sometimes referred to as the North American 3-pin receptacle. This receptacle features a round ground at the bottom and polarized slots with the live slot on the right and the neutral slot on the left.