Wires

Stranded Aluminum Wires Graphic The circuit wires used on overhead distribution lines are generally large un-insulated stranded aluminum wires. The large wire is made up of a series of smaller wires twisted around each other, hence the name "stranded" wire.

Ground Wire Picture Ground wires at each pole help protect the distribution line from lightning strikes. They are connected to the distribution system neutral and also to a ground rod buried near the bottom of the pole. If lightning strikes the neutral or any equipment on the pole, the ground wire provides an easy path for it to get to ground rather than following the distribution system to customer's electrical services. Thus, when we say that the lightning charge was "grounded," we mean the charge was channeled along this wire harmlessly to the ground. Distribution lines are usually not damaged if they are adequately grounded.

Underground Cable GraphicCable rather than individual wires is used with underground distribution circuits. An underground distribution cable consists of several insulated conductors, usually copper, wrapped in a protective insulated outer jacket or covering. Each wire in the cable has a different colored insulation for identification of that wire in the circuit.