Electrical Service is the point of connection between the power utility lines and your home premises wiring system. Whether your main electricity comes in through overhead wires that enter a service mast and then pass down through an electric meter or through underground wires, it ends at the main service panel that connects to circuit breakers in your house. A good understanding of how the electrical system functions can help you identify problems with your Electrical Service.
There are different types of Electric Service depending on the size of your home and the type of electrical wiring installed. If you have a large home with many appliances and electronics, you may need a 200 amp service or higher to ensure adequate power. Smaller homes can usually accommodate 60 to 100 amps.
The most common type of Electric Service is a 120/240-volt main line that feeds your circuit breaker panel. These two 120-volt wires offer a combined 240 volts of electricity to power larger loads like electric hot water heaters and air conditioners. The neutral wire that is bonded to ground supplies 120-volts of electricity for smaller loads like lights and outlets.
Power lines can be either underground or aboveground, and the decision is made by the utility company based on cost, safety considerations and distance of the installation. Overhead lines are the most common, although some homes have buried services. Underground lines are much more expensive and time consuming to install.
An electric meter is located next to or on your house. The meter records the amount of electricity you use each month, and it’s also how the utility company charges you for service. There are different styles of meters, from old-fashioned dials to new state-of-the-art digital models that can be read right from your meter box.
Once the power reaches your meter, it travels through an overhead wire that enters the house and up into a metal service mast or down an underground line to a meter base near the front or side of your home. Regardless of the location of your service, there should be a weatherproof disconnect switch right after the meter, which is sometimes called a “safety switch” or “service disconnect.” The switches are required to make it easy for homeowners to turn off their electricity.
The last part of the main electrical system is the main service panel, which splits the incoming power into the various circuits that run through your house to supply electricity to lights, outlets and other appliances. The panel is often a gray box mounted in a utility area of the garage, basement or furnace room. Homes built before 1950 used 30-amp fuse panels that provided 120-volt current, but these are generally insufficient for modern usage and will need to be updated. Later homes typically have circuit breaker panels that can be upgraded to provide more amperage for expansion and remodeling projects.