Electrical Service is the network of wires and equipment that provides power from a public utility company to homes, commercial buildings and other structures. This power is transmitted over a series of power lines and substations to the electrical distribution system that delivers it to individual consumers.
Typically the first stop for electricity after it leaves a utility pole is an electrical meter at your house. This is usually located in a garage or basement and may also be contained inside a cabinet mounted on an exterior house wall. The next stop is your main electrical panel. This is a gray metal box that splits the power into branch circuits that go to your lights, outlets and appliances. This is where a professional should make any repairs or installations as attempting it on your own can be dangerous.
The most common electric service at residential homes is a 120/240V Delta-Y (pronounced Wye) service. This has two ungrounded conductors (line 1 and line 2) that provide 240V to your home and a neutral that is bonded to ground. Lines 1 and 2 are the larger double pole breakers while the neutral is a standard single-pole breaker. This type of service is used to power larger loads in a home such as an electric hot water heater and air conditioner.
When it comes to commercial properties the power can be delivered underground or overhead. When the power is delivered overhead it must be in a service drop or lateral that follows specific clearances for safety. Inspectors should inspect this portion of the building for proper clearances, service entrance conductors and service grounding and bonding.