Home Wiring Diagrams Terms and Tools Used by Pros

Home wiring set-up
••• Jdickert / Flickr

Understanding home wiring basic diagrams are important on your remodeling project. If you are not an electrical contractor it might present additional challenges. Furthermore, you might end up with an erroneous electrical installation presenting safety hazards to building’s occupants. A house wiring diagram is usually part of a set of design blueprints and it shows the location of electrical outlets (receptacles, switches, light outlets, appliances). This article presents some wiring basics from the overhead wires to the interior of the home.

Home Wiring Diagrams

  • Service Head: Also known as weather head or weather cap is the entry point for aerial electrical wiring installation into a home or building. It is used on home wiring diagrams to identify the point where wires will enter the home. It is shaped like a hood, providing weatherproof protection, where the wires enter facing down at an angle of at least 45 degrees. Three wires carry the standard 240-volt service to your home (two wires carry 120-volt current and one grounded neutral wire).
  • Electric Meter: The electric meter device is presented on home wiring diagrams as the point where all measurements of how much power are used through that particular point. The most common unit of measurement on the electricity meter is the kilowatt hour, which is equal to the amount of energy used by a load of one kilowatt over a period of one hour, or 3,600,000 joules.
  • Main Service Panel: The main service panel or breaker box distributes power to all circuits throughout the building. An electrical service panel is the main distribution center of your house's electricity. Each circuit has a fuse or breaker that can shut itself down in the event of a short circuit or overload. A circuit breaker panel has two kinds of capacities: its amperage and its space for breakers.
  • Electrical Boxes: A home wiring indicates electrical boxes as the place where you end or connect wires providing power either as a switch or an outlet. An electrical box is almost always required for mounting devices (switch, receptacle) and light fixtures, and also wherever circuit connections or splices are made. Outlets are pretty standard, but GFCIs are required in some rooms and box size is another thing to consider. The National Electrical Code requires connections, either spliced, to a switch, receptacle, or another device, be contained within a plastic or metal electrical box. The outlets provide the “plug-in” access to the power 125-volt, 15-amp, three-prong outlets are the most common sense 1965.
  • Ground: A home wiring diagram requires using a ground wire. The ground wire connects the system to the earth through copper rods or metal water pipes. Electrical current runs through the circuit and returns to its original source by means of a white neutral wire that returns power current to the main service panel.

It is important to highlight that power coming from the service head to the electric meter, and then to the main service panel is always live. Before working on these areas the power company must shut the power off.

Home wiring basics require a few handy tools to perform the job. Below is a list of common tools needed to take care of electrical jobs, many of these tools can be found at hardware stores or electrical wholesalers.