Though most of the older homes have an overhead service connection, underground services are becoming the overall favorite among homeowners. these buried lines are more appealing to the eye and the surrounding landscape area than power poles and overhead lines draped acroos someone's yard. but just like overhead service line feeders, there are rules that must be followed when installing these lines. And unlike overhead lines, underground feeders present their own dangers.
The primary power comes from the utility company's power lines via a transformer mounted on the power pole. The line is called a service drop and is to be a minimum of 12 feet above a driveway. The point of attachment to a house's service connection should be a minimum of 10 feet above the ground.
The service drop is connected to the electrical service entrance wires via a service usually attached to the side of your house. This service cosists of an electric meter that is attahed to a pipe with a weatherhead atop it. Inside the pipe, feeder wires are connected to the line side of the meter and the other end sticks out of the service pipe through the weatherhead where the utility company makes the connection to their power lines, called the point of attachment or splice point. The utility company's wires must be supported either by the the service entrance pipe or a mast support screwed into the building framework of the house.
Underground feeders have their own rules and regulations. They must be fed through conduit underground to a depth of four feet before they can be run unexposed underground. There is nothing wrong with running conduit the entire length of the run to the service pole, but the cost and time may be a factor in this decision. It is likely that the utility company will run the feeders underground to your home. Be sure to call the unground utility hotline before digging anywhere on your property. This will tell you what underground utitlities and obstructions are in your way before you dig. If you don't call and damage something, you'll have to likely pay a fine and the repair costs.
Underground services use conduit to protect the feeders from things like lawn mower blades and weed eaters that would otherwise damage the wires. For that reason, the National Electrical Code requires conduit to protect the wires.
There are three service conductor wires that come into a service panel feed. That includes two hot feeder wires and a neutral wire that bonds to the case ground of the service. This ground is then conneced and bonded to both the water pipe within the home a ground rod mounted in the immediate vicinity of the electrical meter outside your home.
So when it's time to update the service panel on your home, consider the two choices that are available to you today. Either way, the utility company will connect to your electrical service and have the electricity flowing to your home.