A service is a set of conductors that provide electric power to a building. The National Electrical Code defines the term as “the conductors and equipment for delivering electricity from the power supply system to the wiring systems of the premises served.”
A residential home’s main electrical service typically contains 120 or 240 volts. The voltage is the amount of energy that can flow through a wire at a given rate (amperage).
The conductors coming into a house from the electric utility are called a “service drop” or, if they’re buried underground, a “service lateral.” These are always live and will remain so until the meter is connected to them. It’s on the customer to furnish and maintain these parts of the system.
While a homeowner can make minor repairs on their own, major work should only be completed by an electrician who is licensed. If you try to do the work yourself, it could be very dangerous, especially if you have tools on hand such as screwdrivers, wire cutters, or pliers. These items can accidentally touch parts of the service wires and transmit an electric shock to you.
When performing an inspection on a residential property, look for a weatherproof disconnect right after the meter connection. This will allow the homeowner to disconnect power from the utility without having to go inside their home. Also, pay attention to the number of conductors on the overhead service drop. If there are only two, this indicates a single-phase system. Three wires on the mast means a three-phase system. Electrical Service